2026.3.0

app/controllers/customers_controller.rb

@@ -120,18 +120,6 @@ class CustomersController < ApplicationController
     end
   end
 
-  # delete a customer
-  def destroy
-    begin
-      Customer.find_by_id(params[:id]).destroy
-      flash[:notice] = t :notice_customer_deleted
-      redirect_to action: :index
-    rescue 
-      flash[:error] = t :notice_customer_not_deleted
-      render_404
-    end
-  end
-
   # creates new customer view tokens, removes expired tokens & redirects to newly created customer view with new token.
   def share
     issue = Issue.find(params[:id])
@@ -212,17 +200,26 @@ class CustomersController < ApplicationController
   end
 
   # format a quickbooks address to a human readable string
-  def address_to_s (address)
+  def address_to_s(address)
     return if address.nil?
-    string = address.line1 if address.line1
-    string << "\n" + address.line2 if address.line2
-    string << "\n" + address.line3 if address.line3
-    string << "\n" + address.line4 if address.line4
-    string << "\n" + address.line5 if address.line5
-    string << " " + address.city if address.city
-    string << ", " + address.country_sub_division_code if address.country_sub_division_code
-    string << " " + address.postal_code if address.postal_code
-    return string
+
+    lines = [
+      address.line1,
+      address.line2,
+      address.line3,
+      address.line4,
+      address.line5
+    ].compact_blank
+
+    city_line = [
+      address.city,
+      address.country_sub_division_code,
+      address.postal_code
+    ].compact_blank.join(" ")
+
+    lines << city_line unless city_line.blank?
+
+    lines.join("\n")
   end
 
   def log(msg)

app/controllers/estimate_controller.rb

@@ -8,71 +8,72 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 class EstimateController < ApplicationController
-  
   include AuthHelper
+
+  before_action :require_user, unless: -> { session[:token].nil? }
+  skip_before_action :verify_authenticity_token, :check_if_login_required, unless: -> { session[:token].nil? }
+  before_action :load_estimate, only: [:show, :doc]
   
-  before_action :require_user, unless: proc {|c| session[:token].nil? }
-  skip_before_action :verify_authenticity_token, :check_if_login_required, unless: proc {|c| session[:token].nil? }
-
-  def get_estimate
-    log "Searching for estimate with params: #{params.inspect}"
-
-    e = Estimate.find_by_doc_number(params[:search]) if params[:search]
-    e = Estimate.find_by_id(params[:id]) if params[:id]
-
-    # Force sync for estimate by doc number if not found
-    if  e.nil? && params[:search]
-      begin
-        Estimate.sync_by_doc_number(params[:search])
-        e = Estimate.find_by_doc_number(params[:search])
-      rescue
-        log "Estimate.find_by_doc_number failed"
-      end
-    end
-
-    # Force sync for estimate by id if not found
-    if  e.nil? && params[:id]
-      begin
-        Estimate.sync_by_id(params[:id])
-        e = Estimate.find_by_id(params[:id])
-      rescue
-        log "Estimate.find_by_id failed"
-      end
-    end
-
-    return e
-  end
-  
-  #
-  # Downloads and forwards the estimate pdf
-  #
-  def show
-    estimate = get_estimate
-
-    begin
-      send_data estimate.pdf, filename: "estimate #{estimate.doc_number}.pdf", disposition: :inline, type: "application/pdf"
-    rescue
-      redirect_to :back, flash: { error: I18n.t(:notice_estimate_not_found) }
-    end
-  end
-
-  #
-  # Downloads estimate by document number
-  #
+  # Displays the estimate PDF in the browser or redirects with an error if not found.
   def doc
-    estimate = get_estimate
-    
-    begin
-      send_data estimate.pdf, filename: "estimate #{estimate.doc_number}.pdf", disposition: :inline, type: "application/pdf"
-    rescue
-      redirect_to :back, flash: { error: I18n.t(:notice_estimate_not_found) }
-    end
+    render_pdf(@estimate)
+  end
+
+  # Displays the estimate PDF in the browser or redirects with an error if not found.
+  def show
+    render_pdf(@estimate)
   end
 
   private
 
+  # Loads the estimate based on ID or doc number, with a fallback to sync if not found locally.
+  def load_estimate
+    log "Attempting to load Estimate with params: #{params.inspect}"
+    @estimate = find_estimate || sync_and_find_estimate
+
+    unless @estimate
+      redirect_back fallback_location: root_path, flash: { error: I18n.t(:notice_estimate_not_found) }
+    end
+  end
+
+  # Attempts to find the estimate locally by ID or doc number.
+  def find_estimate
+    return Estimate.find_by(doc_number: params[:search]) if params[:search].present?
+    return Estimate.find_by(id: params[:id]) if params[:id].present?
+  end
+
+  # If the estimate is not found locally, attempts to sync it from the source and find it again.
+  def sync_and_find_estimate
+
+    if params[:search].present?
+      log "Estimate #{params[:search]} not found locally. Syncing by doc number."
+      Estimate.sync_by_doc_number(params[:search])
+      return Estimate.find_by(doc_number: params[:search])
+    end
+
+    if params[:id].present?
+      log "Estimate #{params[:id]} not found locally. Syncing by ID."
+      Estimate.sync_by_id(params[:id])
+      return Estimate.find_by(id: params[:id])
+    end
+
+    nil
+  rescue StandardError => e
+    log "Estimate sync failed: #{e.message}"
+    nil
+  end
+
+  # Renders the estimate PDF or redirects with an error if rendering fails.
+  def render_pdf(estimate)
+    pdf, ref = EstimatePdfService.new(qbo: QboConnectionService.current!).fetch_pdf(doc_ids: [estimate.id])
+    send_data( pdf, filename: "estimate #{ref}.pdf", disposition: :inline, type: "application/pdf" )
+  rescue StandardError => e
+    log "PDF render failed for Estimate #{estimate&.id}: #{e.message}"
+    redirect_back fallback_location: root_path, flash: { error: I18n.t(:notice_estimate_not_found) }
+  end
+
+  # Logs messages with a consistent prefix for easier debugging.
   def log(msg)
     Rails.logger.info "[EstimateController] #{msg}"
   end
-
-end
+end

app/controllers/invoice_controller.rb

@@ -8,53 +8,29 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 class InvoiceController < ApplicationController
-  
   include AuthHelper
-  require 'combine_pdf'
 
-  before_action :require_user, unless: proc {|c| session[:token].nil? }
-  skip_before_action :verify_authenticity_token, :check_if_login_required, unless: proc {|c| session[:token].nil? }
-  
-  #
-  # Downloads and forwards the invoice pdf
-  #
+  before_action :require_user, unless: -> { session[:token].nil? }
+  skip_before_action :verify_authenticity_token, :check_if_login_required, unless: -> { session[:token].nil? }
+
+  # Displays the invoice PDF in the browser or redirects with an error if not found.
   def show
-    log "Processing request for URL: #{request.original_url}" 
-    begin
-      qbo = Qbo.first
-        qbo.perform_authenticated_request do |access_token|
-        service = Quickbooks::Service::Invoice.new(company_id: qbo.realm_id, access_token: access_token)
-        
-        # If multiple id's then pull each pdf & combine them
-        if params[:invoice_ids]
-          log "Grabbing pdfs for " + params[:invoice_ids].join(', ')
-          ref = ""
-          params[:invoice_ids].each do |i|
-            log "processing " + i
-            invoice = service.fetch_by_id(i)
-            ref += " #{invoice.doc_number}"
-            @pdf << CombinePDF.parse(service.pdf(invoice)) unless @pdf.nil?
-            if @pdf.nil?
-              @pdf = CombinePDF.parse(service.pdf(invoice))
-            end
-          end
-          @pdf = @pdf.to_pdf
-        else
-          invoice = service.fetch_by_id(params[:id])
-          @pdf = service.pdf(invoice)
-          ref = invoice.doc_number
-        end
+    log "Processing request for #{request.original_url}"
 
-        send_data @pdf, filename: "invoice #{ref}.pdf", disposition: :inline, type: "application/pdf"
-      end
-    rescue
-      redirect_to :back, flash: { error: I18n.t(:notice_invoice_not_found) }
-    end
+    invoice_ids = Array(params[:invoice_ids] || params[:id])
+    pdf, ref = InvoicePdfService.new(qbo: QboConnectionService.current!).fetch_pdf(doc_ids: invoice_ids)
+
+    send_data pdf, filename: "invoice #{ref}.pdf", disposition: :inline, type: "application/pdf"
+
+  rescue StandardError => e
+    log "Invoice PDF failure: #{e.message}"
+    redirect_back fallback_location: root_path, flash: { error: I18n.t(:notice_invoice_not_found) }
   end
 
   private
 
+  # Logs messages with a consistent prefix for easier debugging.
   def log(msg)
     Rails.logger.info "[InvoiceController] #{msg}"
   end
-end
+end

app/controllers/qbo_controller.rb

@@ -9,129 +9,68 @@
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 class QboController < ApplicationController
-  
-  require 'openssl'
-  
   include AuthHelper
-  
+
   before_action :require_user, except: :webhook
-  skip_before_action :verify_authenticity_token, :check_if_login_required, only: [:webhook]
+  skip_before_action :verify_authenticity_token, :check_if_login_required, only: :webhook
 
-  def allowed_params
-    params.permit(:code, :state, :realmId, :id)
-  end
-
-  #
-  # Called when the user requests that Redmine to connect to QBO
-  #
+  # Initiates the OAuth authentication process by redirecting the user to the QuickBooks authorization URL. The callback URL is generated based on the application's settings and routes.
   def authenticate
-    redirect_uri = "#{Setting.protocol}://#{Setting.host_name + qbo_oauth_callback_path}"
-    log "redirect_uri: #{redirect_uri}"
-    oauth2_client = Qbo.construct_oauth2_client
-    grant_url = oauth2_client.auth_code.authorize_url(redirect_uri: redirect_uri, response_type: "code", state: SecureRandom.hex(12), scope: "com.intuit.quickbooks.accounting")
-    redirect_to grant_url
+    redirect_to QboOauthService.authorization_url(callback_url: callback_url)
   end
-  
-  #
-  # Called by QBO after authentication has been processed
-  #
+
+  # Handles the OAuth callback from QuickBooks. Exchanges the authorization code for access and refresh tokens, saves the connection details, and redirects to the sync page with a success notice. If any error occurs during the process, logs the error and redirects back to the plugin settings page with an error message.
   def oauth_callback
-    if params[:state].present?
-      oauth2_client = Qbo.construct_oauth2_client
-      # use the state value to retrieve from your backend any information you need to identify the customer in your system
-      redirect_uri = "#{Setting.protocol}://#{Setting.host_name + qbo_oauth_callback_path}"
-      if resp = oauth2_client.auth_code.get_token(params[:code], redirect_uri: redirect_uri)
-        
-        # Remove the last authentication information
-        Qbo.delete_all
-        
-        # Save the authentication information 
-        qbo = Qbo.new
-        qbo.update(oauth2_access_token: resp.token, oauth2_refresh_token: resp.refresh_token, realm_id: params[:realmId])
-        qbo.refresh_token!
-        
-        if qbo.save!
-          redirect_to qbo_sync_path, flash: { notice: I18n.t(:label_connected) }
-        else
-          redirect_to plugin_settings_path(:redmine_qbo), flash: { error: I18n.t(:label_error) }
-        end
-        
-      end
-    end
+    QboOauthService.exchange!(code: params[:code], callback_url: callback_url, realm_id: params[:realmId])
+
+    redirect_to qbo_sync_path, flash: { notice: I18n.t(:label_connected) }
+
+  rescue StandardError => e
+    log "OAuth failure: #{e.message}"
+    redirect_to plugin_settings_path(:redmine_qbo), flash: { error: I18n.t(:label_error) }
   end
-  
-  # Manual Billing
+
+  # Manual billing endpoint to trigger the billing process for a specific issue. Validates the issue and its associations, enqueues a job to bill the issue's time entries, and redirects back to the issue with a notice. If validation fails, redirects back with an error message.
   def bill
     issue = Issue.find_by(id: params[:id])
-    return render_404 unless issue
-
-    unless issue.customer
-      redirect_to issue, flash: { error: I18n.t(:label_billing_error_no_customer) }
-      return
-    end
-
-    unless issue.assigned_to&.employee_id.present?
-      redirect_to issue, flash: { error: I18n.t(:label_billing_error_no_employee) }
-      return
-    end
-
-    unless Qbo.first
-      redirect_to issue, flash: { error: I18n.t(:label_billing_error_no_qbo) }
-      return
-    end
+    raise I18n.t(:notice_error_issue_not_found) unless issue
+    raise I18n.t(:notice_billing_error_no_customer) unless issue.customer
+    raise I18n.t(:notice_billing_error_no_employee) unless issue.assigned_to&.employee_id.present?
+    raise I18n.t(:notice_billing_error_no_qbo) unless Qbo.exists?
 
     BillIssueTimeJob.perform_later(issue.id)
 
-    redirect_to issue, flash: {
-      notice: I18n.t(:label_billing_enqueued) + " #{issue.customer.name}"
-    }
+    redirect_to issue, flash: { notice: "#{I18n.t(:label_billing_enqueued)} #{issue.customer.name}"}
+
+  rescue StandardError => e
+    redirect_to issue || root_path, flash: { error: e.message }
   end
 
-  #
-  # Synchronizes the QboCustomer table with QBO
-  #
+  # Manual sync endpoint to trigger a full synchronization of QuickBooks entities with the local database. Enqueues all relevant sync jobs and redirects to the home page with a notice that syncing has started.
   def sync
-    log "Syncing EVERYTHING"
-
-    CustomerSyncJob.perform_later(full_sync: true)
-    EstimateSyncJob.perform_later(full_sync: true)
-    InvoiceSyncJob.perform_later(full_sync: true)
-    EmployeeSyncJob.perform_later(full_sync: true)
-
+    QboSyncDispatcher.full_sync!
     redirect_to :home, flash: { notice: I18n.t(:label_syncing) }
   end
 
-  # QuickBooks Webhook Callback
+  # Endpoint to receive QuickBooks webhook notifications. Validates the request and processes the payload to sync relevant data to Redmine. Responds with appropriate HTTP status codes based on success or failure of processing.
   def webhook
-    log "Webhook received"
-
-    signature = request.headers['intuit-signature']
-    key       = Setting.plugin_redmine_qbo['settingsWebhookToken']
-    body      = request.raw_post
-
-    digest = OpenSSL::Digest.new('sha256')
-    computed = Base64.strict_encode64(OpenSSL::HMAC.digest(digest, key, body))
-
-    unless secure_compare(computed, signature)
-      log "Invalid webhook signature"
-      head :unauthorized
-      return
-    end
-
-    WebhookProcessJob.perform_later(body)
-
+    QboWebhookProcessor.process!(request: request)
     head :ok
+
+  rescue StandardError => e
+    log "Webhook failure: #{e.message}"
+    head :unauthorized
   end
 
   private
 
-  # Securely compare two strings to prevent timing attacks. Returns false if either string is blank or if they do not match.
-  def secure_compare(a, b)
-    return false if a.blank? || b.blank?
-    ActiveSupport::SecurityUtils.secure_compare(a, b)
+  # Constructs the OAuth callback URL based on the application's settings and routes. This URL is used during the OAuth flow to redirect users back to the application after authentication with QuickBooks.
+  def callback_url
+    "#{Setting.protocol}://#{Setting.host_name}#{qbo_oauth_callback_path}"
   end
 
+  # Logs messages with a consistent prefix for easier debugging and monitoring.
   def log(msg)
     Rails.logger.info "[QboController] #{msg}"
   end
-end
+end

app/jobs/bill_issue_time_job.rb

@@ -10,6 +10,7 @@
 
 class BillIssueTimeJob < ActiveJob::Base
   queue_as :default
+  retry_on StandardError, wait: 5.minutes, attempts: 5
 
   # Perform billing of unbilled time entries for a given issue by creating corresponding TimeActivity records in QuickBooks Online, and then marking those entries as billed in Redmine. This job is typically triggered after an invoice is created or updated to ensure all relevant time is captured for billing.
   def perform(issue_id)
@@ -26,7 +27,7 @@ class BillIssueTimeJob < ActiveJob::Base
       return if totals.blank?
       log "Aggregated hours for billing: #{totals.inspect}"
 
-      qbo = Qbo.first
+      qbo = QboConnectionService.current!
       raise "No QBO configuration found" unless qbo
 
       qbo.perform_authenticated_request do |access_token|
@@ -57,16 +58,10 @@ class BillIssueTimeJob < ActiveJob::Base
   # Create TimeActivity records in QBO for each activity type with the appropriate hours and link them to the issue's assigned employee and customer
   def create_time_activities(issue, totals, access_token, qbo)
     log "Creating TimeActivity records in QBO for issue ##{issue.id}"
-    time_service = Quickbooks::Service::TimeActivity.new(
-      company_id: qbo.realm_id,
-      access_token: access_token
-    )
-
-    item_service = Quickbooks::Service::Item.new(
-      company_id: qbo.realm_id,
-      access_token: access_token
-    )
-
+   
+    time_service = Quickbooks::Service::TimeActivity.new( company_id: qbo.realm_id,  access_token: access_token)
+    item_service = Quickbooks::Service::Item.new( company_id: qbo.realm_id, access_token: access_token )
+    
     totals.each do |activity_name, hours_float|
       next if activity_name.blank?
       next if hours_float.to_f <= 0

app/jobs/customer_sync_job.rb

@@ -14,8 +14,8 @@ class CustomerSyncJob < ApplicationJob
 
   # Perform a full sync of all customers, or an incremental sync of only those updated since the last sync
   def perform(full_sync: false, id: nil)
-    qbo = Qbo.first
-    return unless qbo
+    qbo = QboConnectionService.current!
+    raise "No QBO configuration found" unless qbo
 
     log "Starting #{full_sync ? 'full' : 'incremental'} sync for customer ##{id || 'all'}..."
 

app/jobs/employee_sync_job.rb

@@ -12,9 +12,10 @@ class EmployeeSyncJob < ApplicationJob
   queue_as :default
   retry_on StandardError, wait: 5.minutes, attempts: 5
 
+  # Performs a sync of employees from QuickBooks Online.
   def perform(full_sync: false, id: nil)
-    qbo = Qbo.first
-    return unless qbo
+    qbo = QboConnectionService.current!
+    raise "No QBO configuration found" unless qbo
 
     log "Starting #{full_sync ? 'full' : 'incremental'} sync for employee ##{id || 'all'}..."
 

app/jobs/estimate_sync_job.rb

@@ -12,9 +12,10 @@ class EstimateSyncJob < ApplicationJob
   queue_as :default
   retry_on StandardError, wait: 5.minutes, attempts: 5
 
+  # Performs a sync of estimates from QuickBooks Online.
   def perform(full_sync: false, id: nil, doc_number: nil)
-    qbo = Qbo.first
-    return unless qbo
+    qbo = QboConnectionService.current!
+    raise "No QBO configuration found" unless qbo
 
     log "Starting #{full_sync ? 'full' : 'incremental'} sync for estimate ##{id || doc_number || 'all'}..."
 

app/jobs/invoice_sync_job.rb

@@ -12,9 +12,10 @@ class InvoiceSyncJob < ApplicationJob
   queue_as :default
   retry_on StandardError, wait: 5.minutes, attempts: 5
 
+  # Performs a sync of invoices from QuickBooks Online.
   def perform(full_sync: false, id: nil)
-    qbo = Qbo.first
-    return unless qbo
+    qbo = QboConnectionService.current!
+    raise "No QBO configuration found" unless qbo
 
     log "Starting #{full_sync ? 'full' : 'incremental'} sync for invoice ##{id || 'all'}..."
 

app/jobs/qbo_sync_dispatcher.rb

@@ -0,0 +1,24 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+class QboSyncDispatcher
+
+  SYNC_JOBS = [
+    CustomerSyncJob,
+    EstimateSyncJob,
+    InvoiceSyncJob,
+    EmployeeSyncJob
+  ].freeze
+
+  # Dispatches all synchronization jobs to perform a full sync of QuickBooks entities with the local database. Each job is enqueued with the `full_sync` flag set to true.
+  def self.full_sync!
+    SYNC_JOBS.each { |job| job.perform_later(full_sync: true) }
+  end
+end

app/jobs/qbo_webhook_processor.rb

@@ -0,0 +1,42 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+class QboWebhookProcessor
+
+  # Processes the incoming QuickBooks webhook request by validating the signature and enqueuing a background job to handle the webhook payload. Raises an error if the signature is invalid.
+  def self.process!(request:)
+    body = request.raw_post
+    signature = request.headers['intuit-signature']
+    secret = Setting.plugin_redmine_qbo['settingsWebhookToken']
+
+    raise "Invalid signature" unless valid_signature?(body, signature, secret)
+
+    WebhookProcessJob.perform_later(body)
+  end
+
+  private
+
+  # Validates the QuickBooks webhook request by computing the HMAC signature and comparing it to the provided signature. Returns false if either the signature or secret is blank, or if the computed signature does not match the provided signature.
+  def self.valid_signature?(body, signature, secret)
+    return false if signature.blank? || secret.blank?
+    log "Validating signature"
+
+    digest = OpenSSL::Digest.new('sha256')
+    computed = Base64.strict_encode64(
+      OpenSSL::HMAC.digest(digest, secret, body)
+    )
+
+    ActiveSupport::SecurityUtils.secure_compare(computed, signature)
+  end
+
+  def self.log(msg)
+    Rails.logger.info "[QboWebhookProcessor] #{msg}"
+  end
+end

app/jobs/webhook_process_job.rb

@@ -10,6 +10,7 @@
 
 class WebhookProcessJob < ActiveJob::Base
   queue_as :default
+  retry_on StandardError, wait: 5.minutes, attempts: 5
 
   ALLOWED_ENTITIES = %w[
     Customer

app/models/customer.rb

@@ -215,7 +215,7 @@ class Customer < ActiveRecord::Base
   def pull
     begin
       raise Exception unless self.id
-      qbo = Qbo.first
+      qbo = QboConnectionService.current!
       @details = qbo.perform_authenticated_request do |access_token|
         service = Quickbooks::Service::Customer.new(company_id: qbo.realm_id, access_token: access_token)
         service.fetch_by_id(self.id)

app/models/estimate.rb

@@ -35,17 +35,6 @@ class Estimate < ActiveRecord::Base
     EstimateSyncJob.perform_later(doc_number: number)
   end
 
-  # download the pdf from quickbooks
-  def pdf
-    log "Downloading PDF for estimate ##{self.id}..."
-    qbo = Qbo.first
-    qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Estimate.new(company_id: qbo.realm_id, access_token: access_token)
-      estimate = service.fetch_by_id(id)
-      service.pdf(estimate)
-    end
-  end
-
   # Magic Method
   # Maps Get/Set methods to QBO estimate object
   def method_missing(sym, *arguments)
@@ -71,7 +60,7 @@ class Estimate < ActiveRecord::Base
     log "Pulling details for estimate ##{self.id}..."
     begin
       raise Exception unless self.id
-      qbo = Qbo.first
+      qbo = QboConnectionService.current!
       @details = qbo.perform_authenticated_request do |access_token|
         service = Quickbooks::Service::Estimate.new(company_id: qbo.realm_id, access_token: access_token)
         service(:estimate).fetch_by_id(self.id)

app/models/qbo.rb

@@ -12,24 +12,35 @@ class Qbo < ActiveRecord::Base
     
   include QuickbooksOauth
   include Redmine::I18n
+
+  validate :single_record_only, on: :create
   
   # Updates last sync time stamp
   def self.update_time_stamp
     date = DateTime.now
     log "Updating QBO timestamp to #{date}"
-    qbo = Qbo.first
+    qbo = QboConnectionService.current!
     qbo.last_sync = date
     qbo.save
   end
   
+  # Returns the last sync time formatted for display. If no sync has occurred, returns a default message.
   def self.last_sync
-    format_time(Qbo.first.last_sync)
+    qbo = QboConnectionService.current!
+    return I18n.t(:label_qbo_never_synced) unless qbo&.last_sync
+    format_time(qbo.last_sync)
   end
 
   private
 
+  # Logs a message with a QBO-specific prefix for easier identification in the logs.
   def self.log(msg)
     logger.info "[QBO] #{msg}"
   end
 
+  # Validates that only one QBO connection record exists in the database. Adds an error if a record already exists.
+  def single_record_only
+    errors.add(:base, "Only one QBO connection allowed") if Qbo.exists?
+  end
+
 end

app/services/customer_sync_service.rb

@@ -8,88 +8,25 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-class CustomerSyncService
-  PAGE_SIZE = 1000
-
-  def initialize(qbo:)
-    @qbo = qbo
-  end
-
-  # Sync all customers, or only those updated since the last sync
-  def sync(full_sync: false)
-    log "Starting #{full_sync ? 'full' : 'incremental'} customer sync"
-
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Customer.new(company_id: @qbo.realm_id, access_token: access_token)
-
-      page = 1
-      loop do
-        collection = fetch_page(service, page, full_sync)
-        entries = Array(collection&.entries)
-        break if entries.empty?
-
-        entries.each { |remote| persist(remote) }
-
-        break if entries.size < PAGE_SIZE
-        page += 1
-      end
-    end
-
-    log "Customer sync complete"
-  end
-
-  # Sync a single customer by its QBO ID, used for webhook updates
-  def sync_by_id(id)
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Customer.new(company_id: @qbo.realm_id, access_token: access_token)
-      remote = service.fetch_by_id(id)
-      persist(remote)
-    end
-  end
+class CustomerSyncService < SyncServiceBase
 
   private
 
-  # Fetch a page of customers, either all or only those updated since the last sync
-  def fetch_page(service, page, full_sync)
-    start_position = (page - 1) * PAGE_SIZE + 1
-
-    if full_sync
-      service.query("SELECT * FROM Customer STARTPOSITION #{start_position} MAXRESULTS #{PAGE_SIZE}")
-    else
-      last_update = Customer.maximum(:updated_at) || 1.year.ago
-      service.query(<<~SQL.squish)
-        SELECT * FROM Customer
-        WHERE MetaData.LastUpdatedTime > '#{last_update.utc.iso8601}'
-        STARTPOSITION #{start_position}
-        MAXRESULTS #{PAGE_SIZE}
-      SQL
-    end
+  # Specify the local model this service syncs
+  def self.model_class
+    Customer
   end
 
-  # Create or update a local Customer record based on the QBO remote data
-  def persist(remote)
-    local = Customer.find_or_initialize_by(id: remote.id)
-
-    if remote.active?
-      local.name = remote.display_name
-      local.phone_number = remote.primary_phone&.free_form_number&.gsub(/\D/, '')
-      local.mobile_phone_number = remote.mobile_phone&.free_form_number&.gsub(/\D/, '')
-
-      if local.changed?
-        local.save
-        log "Updated customer #{remote.id}"
-      end
-    else
-      if local.persisted?
-        local.destroy
-        log "Deleted customer #{remote.id}"
-      end
-    end
-  rescue => e
-    log "Failed to sync customer #{remote.id}: #{e.message}"
+  # Determine if the remote entity should be deleted locally (e.g. if it's marked inactive in QBO)
+  def destroy_remote?(remote)
+    !remote.active?
   end
 
-  def log(msg)
-    Rails.logger.info "[CustomerSyncService] #{msg}"
+  # Map relevant attributes from the QBO Customer to the local Customer model
+  def process_attributes(local, remote)
+    local.name = remote.display_name
+    local.phone_number = remote.primary_phone&.free_form_number&.gsub(/\D/, '')
+    local.mobile_phone_number = remote.mobile_phone&.free_form_number&.gsub(/\D/, '')
   end
+
 end

app/services/employee_sync_service.rb

@@ -8,86 +8,23 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-class EmployeeSyncService
-  PAGE_SIZE = 1000
-
-  def initialize(qbo:)
-    @qbo = qbo
-  end
-
-  # Sync all employees, or only those updated since the last sync
-  def sync(full_sync: false)
-    log "Starting #{full_sync ? 'full' : 'incremental'} employee sync"
-
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Employee.new(company_id: @qbo.realm_id, access_token: access_token)
-
-      page = 1
-      loop do
-        collection = fetch_page(service, page, full_sync)
-        entries = Array(collection&.entries)
-        break if entries.empty?
-
-        entries.each { |remote| persist(remote) }
-
-        break if entries.size < PAGE_SIZE
-        page += 1
-      end
-    end
-
-    log "Employee sync complete"
-  end
-
-  # Sync a single employee by its QBO ID, used for webhook updates
-  def sync_by_id(id)
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Employee.new(company_id: @qbo.realm_id, access_token: access_token)
-      remote = service.fetch_by_id(id)
-      persist(remote)
-    end
-  end
+class EmployeeSyncService < SyncServiceBase
 
   private
 
-  # Fetch a page of employees, either all or only those updated since the last sync
-  def fetch_page(service, page, full_sync)
-    start_position = (page - 1) * PAGE_SIZE + 1
-
-    if full_sync
-      service.query("SELECT * FROM Employee STARTPOSITION #{start_position} MAXRESULTS #{PAGE_SIZE}")
-    else
-      last_update = Employee.maximum(:updated_at) || 1.year.ago
-      service.query(<<~SQL.squish)
-        SELECT * FROM Employee
-        WHERE MetaData.LastUpdatedTime > '#{last_update.utc.iso8601}'
-        STARTPOSITION #{start_position}
-        MAXRESULTS #{PAGE_SIZE}
-      SQL
-    end
+  # Specify the local model this service syncs
+  def self.model_class
+    Employee
   end
 
-  # Create or update a local Employee record based on the QBO remote data
-  def persist(remote)
-    local = Employee.find_or_initialize_by(id: remote.id)
-
-    if remote.active?
-      local.name = remote.display_name
-
-      if local.changed?
-        local.save
-        log "Updated employee #{remote.id}"
-      end
-    else
-      if local.persisted?
-        local.destroy
-        log "Deleted employee #{remote.id}"
-      end
-    end
-  rescue => e
-    log "Failed to sync employee #{remote.id}: #{e.message}"
+  # Determine if the remote entity should be deleted locally (e.g. if it's marked inactive in QBO)
+  def destroy_remote?(remote)
+    !remote.active?
   end
 
-  def log(msg)
-    Rails.logger.info "[EmployeeSyncService] #{msg}"
+  # Map relevant attributes from the QBO Employee to the local Employee model
+  def process_attributes(local, remote)
+    local.name = remote.display_name
   end
+
 end

app/services/estimate_pdf_service.rb

@@ -0,0 +1,16 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+class EstimatePdfService < PdfServiceBase
+
+  def self.model_class
+    Estimate
+  end
+
+end

app/services/estimate_sync_service.rb

@@ -8,95 +8,20 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-class EstimateSyncService
-  PAGE_SIZE = 1000
-
-  def initialize(qbo:)
-    @qbo = qbo
-  end
-
-  # Sync all estimates, or only those updated since the last sync
-  def sync(full_sync: false)
-    log "Starting #{full_sync ? 'full' : 'incremental'} estimate sync"
-
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Estimate.new(company_id: @qbo.realm_id, access_token: access_token)
-
-      page = 1
-      loop do
-        collection = fetch_page(service, page, full_sync)
-        entries = Array(collection&.entries)
-        break if entries.empty?
-
-        entries.each { |remote| persist(remote) }
-
-        break if entries.size < PAGE_SIZE
-        page += 1
-      end
-    end
-
-    log "Estimate sync complete"
-  end
-
-  # Sync a single estimate by its QBO ID, used for webhook updates
-  def sync_by_doc(doc_number)
-    log "Syncing estimate by doc_number: #{doc_number}"
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Estimate.new(company_id: @qbo.realm_id, access_token: access_token)
-      remote = service.find_by( :doc_number, doc_number).first
-      log "Found estimate with ID #{remote.id} for doc_number #{doc_number}" if remote
-      persist(remote)
-    end
-  end
-
-  # Sync a single estimate by its QBO ID, used for webhook updates
-  def sync_by_id(id)
-    log "Syncing estimate by ID: #{id}"
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Estimate.new(company_id: @qbo.realm_id, access_token: access_token)
-      remote = service.fetch_by_id(id)
-      persist(remote)
-    end
-  end
-
+class EstimateSyncService < SyncServiceBase
+  
   private
 
-  # Fetch a page of estimates, either all or only those updated since the last sync
-  def fetch_page(service, page, full_sync)
-    log "Fetching page #{page} of estimates (full_sync: #{full_sync})"
-    start_position = (page - 1) * PAGE_SIZE + 1
-
-    if full_sync
-      service.query("SELECT * FROM Estimate STARTPOSITION #{start_position} MAXRESULTS #{PAGE_SIZE}")
-    else
-      last_update = Estimate.maximum(:updated_at) || 1.year.ago
-      service.query(<<~SQL.squish)
-        SELECT * FROM Estimate
-        WHERE MetaData.LastUpdatedTime > '#{last_update.utc.iso8601}'
-        STARTPOSITION #{start_position}
-        MAXRESULTS #{PAGE_SIZE}
-      SQL
-    end
+  # Specify the local model this service syncs
+  def self.model_class
+    Estimate
   end
 
-  # Create or update a local Estimate record based on the QBO remote data
-  def persist(remote)
-    log "Persisting estimate #{remote.id}"
-    local = Estimate.find_or_initialize_by(id: remote.id)
-
+  # Map relevant attributes from the QBO Estimate to the local Estimate model
+  def process_attributes(local, remote)
     local.doc_number = remote.doc_number
     local.txn_date = remote.txn_date
     local.customer = Customer.find_by(id: remote.customer_ref&.value)
-    
-    if local.changed?
-      local.save
-      log "Updated estimate #{remote.id}"
-    end
-  rescue => e
-    log "Failed to sync estimate #{remote.id}: #{e.message}"
   end
 
-  def log(msg)
-    Rails.logger.info "[EstimateSyncService] #{msg}"
-  end
 end

app/services/invoice_pdf_service.rb

@@ -0,0 +1,16 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+class InvoicePdfService < PdfServiceBase
+
+  def self.model_class
+    Invoice
+  end
+
+end

app/services/invoice_push_service.rb

@@ -22,7 +22,7 @@ class InvoicePushService
 
     @invoice.update_column(:qbo_sync_locked, true)
 
-    qbo = Qbo.first
+    qbo = QboConnectionService.current!
 
     qbo.perform_authenticated_request do |access_token|
       service = Quickbooks::Service::Invoice.new( company_id: qbo.realm_id, access_token: access_token)

app/services/invoice_sync_service.rb

@@ -8,88 +8,28 @@
 #
 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-class InvoiceSyncService
-  PAGE_SIZE = 1000
-
-  def initialize(qbo:)
-    @qbo = qbo
-  end
-
-  # Sync all invoices, or only those updated since the last sync
-  def sync(full_sync: false)
-    log "Starting #{full_sync ? 'full' : 'incremental'} invoice sync"
-
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Invoice.new(company_id: @qbo.realm_id, access_token: access_token)
-
-      page = 1
-      loop do
-        collection = fetch_page(service, page, full_sync)
-        entries = Array(collection&.entries)
-        break if entries.empty?
-
-        entries.each { |remote| persist(remote) }
-
-        break if entries.size < PAGE_SIZE
-        page += 1
-      end
-    end
-
-    log "Invoice sync complete"
-  end
-
-  # Sync a single invoice by its QBO ID, used for webhook updates
-  def sync_by_id(id)
-    @qbo.perform_authenticated_request do |access_token|
-      service = Quickbooks::Service::Invoice.new(company_id: @qbo.realm_id, access_token: access_token)
-      remote = service.fetch_by_id(id)
-      persist(remote)
-    end
-  end
-
+class InvoiceSyncService < SyncServiceBase
+  
   private
 
-  # Fetch a page of invoices, either all or only those updated since the last sync
-  def fetch_page(service, page, full_sync)
-    start_position = (page - 1) * PAGE_SIZE + 1
-
-    if full_sync
-      service.query("SELECT * FROM Invoice STARTPOSITION #{start_position} MAXRESULTS #{PAGE_SIZE}")
-    else
-      last_update = Invoice.maximum(:qbo_updated_at) || 1.year.ago
-      service.query(<<~SQL.squish)
-        SELECT * FROM Invoice
-        WHERE MetaData.LastUpdatedTime > '#{last_update.utc.iso8601}'
-        STARTPOSITION #{start_position}
-        MAXRESULTS #{PAGE_SIZE}
-      SQL
-    end
+  # Specify the local model this service syncs
+  def self.model_class
+    Invoice
   end
-
-  # Create or update a local Invoice record based on the QBO remote data
-  def persist(remote)
-    local = Invoice.find_or_initialize_by(id: remote.id)
-
+  
+  # Map relevant attributes from the QBO Invoice to the local Invoice model
+  def process_attributes(local, remote)
     local.doc_number      = remote.doc_number
     local.txn_date        = remote.txn_date
     local.due_date        = remote.due_date
     local.total_amount    = remote.total
     local.balance         = remote.balance
     local.qbo_updated_at  = remote.meta_data&.last_updated_time
-
     local.customer = Customer.find_by(id: remote.customer_ref&.value)
-
-    if local.changed?
-      local.save
-      log "Updated invoice #{remote.doc_number} (#{remote.id})"
-    end
-
-    InvoiceAttachmentService.new(local, remote).attach
-    rescue => e
-    log "Failed to sync invoice #{remote.doc_number} (#{remote.id}): #{e.message}"
   end
 
-  def log(msg)
-    Rails.logger.info "[InvoiceSyncService] #{msg}"
+  # Attach QBO Invoices to the local Issues
+  def attach_documents(local, remote)
+    InvoiceAttachmentService.new(local, remote).attach
   end
 end

app/services/pdf_service_base.rb

@@ -0,0 +1,66 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+class PdfServiceBase
+  
+  require 'combine_pdf'
+
+  # Subclasses should initialize with a QBO client instance
+  def initialize(qbo:)
+    @qbo = qbo
+    @entity = self.class.model_class
+  end
+
+  # Subclasses must implement this to specify which document model to download pdf (e.g. Estimate, Invoice)
+  def self.model_class
+    raise NotImplementedError
+  end
+
+  # Fetches the PDF for the given entity IDs. If multiple IDs are provided, their PDFs are combined into a single document.
+  def fetch_pdf(doc_ids:)
+    log "Fetching PDFs for #{@entity} IDs: #{doc_ids.join(', ')}"
+    @qbo.perform_authenticated_request do |access_token|
+      service_class = "Quickbooks::Service::#{@entity.name}".constantize
+      service = service_class.new(company_id: @qbo.realm_id, access_token: access_token)
+      
+      return single_pdf(service, doc_ids.first) if doc_ids.size == 1
+
+      combined_pdf(service, doc_ids)
+    end
+  end
+
+  private
+
+  # Fetches a single PDF for the given invoice ID.
+  def single_pdf(service, id)
+    log "Fetching PDF for #{@entity} ID: #{id}"
+    entity = service.fetch_by_id(id)
+    [service.pdf(entity), entity.doc_number]
+  end
+
+  # Combines PDFs for multiple entity IDs into a single PDF document and returns it along with a reference string.
+  def combined_pdf(service, ids)
+    log "Combining PDFs for #{@entity} IDs: #{ids.join(', ')}"
+    pdf = CombinePDF.new
+    ref = []
+
+    ids.each do |id|
+      entity = service.fetch_by_id(id)
+      ref << entity.doc_number
+      pdf << CombinePDF.parse(service.pdf(entity))
+    end
+
+    [pdf.to_pdf, ref.join(" ")]
+  end
+
+  # Logs messages with a consistent prefix for easier debugging.
+  def log(msg)
+    Rails.logger.info "[#{@entity}PdfService] #{msg}"
+  end
+end

app/services/qbo_connection_service.rb

@@ -0,0 +1,32 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+class QboConnectionService
+
+  # Replaces the existing QBO connection with new credentials. Deletes all existing records and creates a new one with the provided token, refresh token, and realm ID. Refreshes the token immediately after creation.
+  def self.replace!(token:, refresh_token:, realm_id:)
+    Qbo.transaction do
+      Qbo.destroy_all
+      qbo = Qbo.create!(
+        oauth2_access_token: token,
+        oauth2_refresh_token: refresh_token,
+        realm_id: realm_id
+      )
+      qbo.refresh_token!
+      qbo
+    end
+  end
+
+  # Returns the current QBO connection record. Raises an error if no connection exists.
+  def self.current!
+    Qbo.first || raise("QBO not connected")
+  end
+
+end

app/services/qbo_oauth_service.rb

@@ -0,0 +1,33 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+class QboOauthService
+
+  # Generates the QuickBooks OAuth authorization URL with the specified callback URL. The URL includes necessary parameters such as response type, state, and scope.
+  def self.authorization_url(callback_url:)
+    client.auth_code.authorize_url(
+      redirect_uri: callback_url,
+      response_type: "code",
+      state: SecureRandom.hex(12),
+      scope: "com.intuit.quickbooks.accounting"
+    )
+  end
+
+  # Exchanges the authorization code for access and refresh tokens. Creates or replaces the QBO connection record with the new credentials and refreshes the token immediately after creation.
+  def self.exchange!(code:, callback_url:, realm_id:)
+    resp = client.auth_code.get_token(code, redirect_uri: callback_url)
+    QboConnectionService.replace!( token: resp.token, refresh_token: resp.refresh_token, realm_id: realm_id )
+  end
+
+  # Constructs and returns an OAuth2 client instance configured with the application's credentials and settings.
+  def self.client
+    Qbo.construct_oauth2_client
+  end
+end

app/services/sync_service_base.rb

@@ -0,0 +1,126 @@
+#The MIT License (MIT)
+#
+#Copyright (c) 2016 - 2026 rick barrette
+#
+#Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+#The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+#
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+class SyncServiceBase
+  PAGE_SIZE = 1000
+
+  # Subclasses should initialize with a QBO client instance
+  def initialize(qbo:)
+    @qbo = qbo
+    @entity = self.class.model_class
+  end
+
+  # Subclasses must implement this to specify which local model they sync (e.g. Customer, Invoice)
+  def self.model_class
+    raise NotImplementedError
+  end
+
+  # Sync all entities, or only those updated since the last sync
+  def sync(full_sync: false)
+    log "Starting #{full_sync ? 'full' : 'incremental'} #{@entity.name} sync"
+
+    @qbo.perform_authenticated_request do |access_token|
+      service_class = "Quickbooks::Service::#{@entity.name}".constantize
+      service = service_class.new(company_id: @qbo.realm_id, access_token: access_token)
+      
+      page = 1
+      loop do
+        collection = fetch_page(service, page, full_sync)
+        entries = Array(collection&.entries)
+        break if entries.empty?
+
+        entries.each { |remote| persist(remote) }
+
+        break if entries.size < PAGE_SIZE
+        page += 1
+      end
+    end
+
+    log "#{@entity.name} sync complete"
+  end
+
+  # Sync a single entity by its QBO ID, used for webhook updates
+  def sync_by_id(id)
+    log "Syncing #{@entity.name} with ID #{id}"
+    @qbo.perform_authenticated_request do |access_token|
+      service_class = "Quickbooks::Service::#{@entity.name}".constantize
+      service = service_class.new(company_id: @qbo.realm_id, access_token: access_token)
+      remote = service.fetch_by_id(id)
+      persist(remote)
+    end
+  end
+
+  private
+
+  def attach_documents(local, remote)
+    # Override in subclasses if the entity has attachments (e.g. Invoice)
+  end
+
+  # Determine if a remote entity should be deleted locally (e.g. if it's marked inactive in QBO)
+  def destroy_remote?(remote)
+    false
+  end
+
+  # Log messages with the entity type for better traceability
+  def log(msg)
+    Rails.logger.info "[#{@entity.name}SyncService] #{msg}"
+  end
+
+  # Fetch a page of entities, either all or only those updated since the last sync
+  def fetch_page(service, page, full_sync)
+    log "Fetching page #{page} of #{@entity.name} from QBO (#{full_sync ? 'full' : 'incremental'} sync)"
+    start_position = (page - 1) * PAGE_SIZE + 1
+
+    if full_sync
+      service.query("SELECT * FROM #{@entity.name} STARTPOSITION #{start_position} MAXRESULTS #{PAGE_SIZE}")
+    else
+      last_update = @entity.maximum(:updated_at) || 1.year.ago
+      service.query(<<~SQL.squish)
+        SELECT * FROM #{@entity.name}
+        WHERE MetaData.LastUpdatedTime > '#{last_update.utc.iso8601}'
+        STARTPOSITION #{start_position}
+        MAXRESULTS #{PAGE_SIZE}
+      SQL
+    end
+  end
+
+  # Create or update a local entity record based on the QBO remote data
+  def persist(remote)
+    local = @entity.find_or_initialize_by(id: remote.id)
+
+    if destroy_remote?(remote)
+      if local.persisted?
+        local.destroy
+        log "Deleted #{@entity.name} #{remote.id}"
+      end
+      return
+    end
+
+    # Map remote attributes to local model fields, this should be implemented in subclasses
+    process_attributes(local, remote)
+
+    if local.changed?
+      local.save!
+      log "Updated #{@entity.name} #{remote.id}"
+
+      # Handle attaching documents if applicable to invoices
+      attach_documents(local, remote) 
+    end
+
+  rescue => e
+      log "Failed to sync #{@entity.name} #{remote.id}: #{e.message}"
+  end
+
+  # This method should be implemented in subclasses to map remote attributes to local model
+  def process_attributes(local, remote)
+    raise NotImplementedError, "Subclasses must implement process_attributes"
+  end
+
+end

app/views/customers/_details.html.erb

@@ -23,12 +23,12 @@
     
      <tr>
         <th><%=t(:label_billing_address)%></th>
-        <td><%= @billing_address %></td>
+        <td><pre><%= @billing_address %></pre></td>
     </tr>
     
      <tr>
         <th><%=t(:label_shipping_address)%></th>
-        <td><%= @shipping_address %></td>
+        <td><pre><%= @shipping_address %></pre></td>
     </tr>
     
     <tr>

app/views/qbo/_settings.html.erb

@@ -66,12 +66,12 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
      <tr>
         <th><%=t(:label_oauth_expires)%></th>
-        <td><%= if Qbo.exists? then Qbo.first.oauth2_access_token_expires_at end %>
+        <td><%= if Qbo.exists? then QboConnectionService.current!.oauth2_access_token_expires_at end %>
       </tr>
       
       <tr>
         <th><%=t(:label_oauth2_refresh_token_expires_at)%></th>
-        <td><%= if Qbo.exists? then Qbo.first.oauth2_refresh_token_expires_at end %>
+        <td><%= if Qbo.exists? then QboConnectionService.current!.oauth2_refresh_token_expires_at end %>
      </tr>
 
   </tbody>

config/locales/en.yml

@@ -27,10 +27,6 @@ en:
   label_balance_with_jobs: "Balance With Jobs"
   label_bill_time: "Bill Time"
   label_billing_address: "Billing Address"
-  label_billing_error: "Customer could not be billed. Check for Customer or Assignee and try again."
-  label_billing_error_no_customer: "Cannot bill without an assigned customer."
-  label_billing_error_no_employee: "Cannot bill without an assigned employee."
-  label_billing_error_no_qbo: "Cannot bill without a QuickBooks connection. Please connect to QuickBooks and try again."
   label_billing_enqueued: "Billing has been enqueued for issue"
   label_billed_success: "Successfully billed "
   label_client_id: "Intuit QBO OAuth2 Client ID"
@@ -66,6 +62,7 @@ en:
   label_model: "Model"
   label_name: "Name"
   label_new_customer: "New Customer"
+  label_qbo_never_synced: "Never Synced"
   label_no_customers: "There are no customers matching the search term(s)."
   label_no_estimates: "No Estimates"
   label_no_invoices: "No Invoices"
@@ -90,11 +87,15 @@ en:
   label_webhook_token: "Intuit QBO Webhook Token"
   label_week: "Week"
   label_year: "Year"
+  notice_billing_error_no_customer: "Cannot bill without an assigned customer."
+  notice_billing_error_no_employee: "Cannot bill without an assigned employee."
+  notice_billing_error_no_qbo: "Cannot bill without a QuickBooks connection. Please connect to QuickBooks and try again."
   notice_customer_created: "Customer created in QuickBooks"
   notice_customer_deleted: "Customer deleted in QuickBooks"
   notice_customer_not_deleted: "Customer could not be deleted in QuickBooks"
   notice_customer_not_found: "Customer not found in QuickBooks"
   notice_customer_updated: "Customer updated in QuickBooks"
+  notice_error_issue_not_found: "The issue could not be found. Please check the issue and try again."
   notice_error_project_nil: "The issue's project is nil. Set project to:"
   notice_error_tracker_nil: "The issue's tracker is nil. Set tracker to:"
   notice_estimate_created: "Estimate created in QuickBooks"

db/migrate/032_add_txn_dates.rb

@@ -14,42 +14,6 @@ class AddTxnDates < ActiveRecord::Migration[5.1]
     begin
       add_column :qbo_invoices, :txn_date, :date
       add_column :qbo_estimates, :txn_date, :date
-
-      reversible do |direction|
-        direction.up {
-          break unless Qbo.first
-
-          QboEstimate.reset_column_information
-          QboInvoice.reset_column_information
-
-          say "Sync Estimates"
-
-          QboEstimate.sync
-
-          say "Sync Invoices"
-
-          qbo = Qbo.first
-          invoices = qbo.perform_authenticated_request do |access_token|
-            service = Quickbooks::Service::Invoice.new(company_id: qbo.realm_id, access_token: access_token)
-            service.all
-          end
-
-          return unless invoices
-
-          invoices.each { |invoice|
-              # Load the invoice into the database
-              qbo_invoice = QboInvoice.find_or_create_by(id: invoice.id)
-              qbo_invoice.doc_number = invoice.doc_number
-              qbo_invoice.id = invoice.id
-              qbo_invoice.customer_id = invoice.customer_ref
-              qbo_invoice.txn_date = invoice.txn_date
-              qbo_invoice.save!
-          }
-        }
-      end
-    rescue
-      logger.error "AddTxnDates Failed"
-    end
   end
 
 end

init.rb

@@ -14,7 +14,7 @@ Redmine::Plugin.register :redmine_qbo do
   name 'Redmine QBO plugin'
   author 'Rick Barrette'
   description 'A pluging for Redmine to connect with QuickBooks Online to create Time Activity Entries for billable hours logged when an Issue is closed'
-  version '2026.2.16'
+  version '2026.3.0'
   url 'https://github.com/rickbarrette/redmine_qbo'
   author_url 'https://barrettefabrication.com'
   settings default: {empty: true}, partial: 'qbo/settings'

lib/redmine_qbo/patches/issue_patch.rb

@@ -39,11 +39,9 @@ module RedmineQbo
         # Enqueue a background job to bill the time spent on this issue to the associated customer in Quickbooks, if the issue is closed and has a customer assigned.
         def enqueue_billing
           log "Checking if issue needs to be billed for issue ##{id}"
-          #return unless saved_change_to_status_id?
           return unless closed?
           return unless customer.present?
           return unless assigned_to&.employee_id.present?
-          return unless Qbo.first
 
           log "Enqueuing billing for issue ##{id}"
           BillIssueTimeJob.perform_later(id)