record errors and decode existing vins on migration

app/controllers/vehicles_controller.rb

@@ -76,10 +76,20 @@ class VehiclesController < ApplicationController
     end
   end
 
+  # used by the polling JS in vehicle#show
   def status
     vehicle = Vehicle.find(params[:id])
+
+    # decode the vin if it hasn't been done for some reason
+    unless vehicle.vin_decoded
+      if vehicle.error.nil?
+        VehicleVinDecodeJob.perform_later(vehicle)
+      end
+    end
+    
     render json: {
-      decoded: vehicle.vin_decoded
+      decoded: vehicle.vin_decoded,
+      error: vehicle.error
     }
   end
 

app/jobs/vehicle_vin_decode_job.rb

@@ -20,7 +20,7 @@ class VehicleVinDecodeJob < ApplicationJob
     
     unless result.success?
       log "Failed to decode vin"
-      vehicle.update(vin_decoded: false)
+      vehicle.update(vin_decoded: false, error: result.error)
       return
     end
 
@@ -33,7 +33,8 @@ class VehicleVinDecodeJob < ApplicationJob
       doors: details.doors.presence || vehicle.doors,
       trim: details.trim.presence || vehicle.trim,
       name: vehicle.to_s,
-      vin_decoded: true
+      vin_decoded: true,
+      error: nil
     )
   end
 

app/views/vehicles/show.html.erb

@@ -1,8 +1,12 @@
 <h2><%=t(:field_vehicle)%> #<%=@vehicle.id%></h2>
 
 <% unless @vehicle.vin_decoded? %>
-  <div id="vin-status" class="flash notice">
-    <%= t :notice_decoding_vin %>
+  <div id="vin-status" class="flash <%= @vehicle.error ? "error" : "notice" %>">
+    <% if @vehicle.error%>
+      <%= @vehicle.error %>
+    <% else %>
+      <%= t :notice_decoding_vin %>
+    <% end %>
   </div>
 <% end %>
 
@@ -35,9 +39,11 @@
 
     if (alreadyDecoded) return;
 
-    const interval = 3000; // 3 seconds
+    const interval = 3000;
     let attempts = 0;
-    const maxAttempts = 40; // ~2 minutes
+    const maxAttempts = 40;
+
+    const statusEl = document.getElementById("vin-status");
 
     const checkStatus = () => {
       fetch(`/vehicles/${vehicleId}/status`, {
@@ -45,19 +51,51 @@
       })
         .then(res => res.json())
         .then(data => {
+
+          // SUCCESS → reload
           if (data.decoded) {
             window.location.reload();
-          } else {
-            attempts++;
-            if (attempts >= maxAttempts) {
-              clearInterval(timer);
-              console.warn("VIN decode polling timed out");
+            return;
+          }
+
+          // ERROR → stop + show message
+          if (data.error) {
+            clearInterval(timer);
+
+            if (statusEl) {
+              statusEl.classList.remove("notice");
+              statusEl.classList.add("error");
+              statusEl.textContent = data.error;
             }
+
+            console.warn("VIN decode failed:", data.error);
+            return;
+          }
+
+          // continue polling
+          attempts++;
+          if (attempts >= maxAttempts) {
+            clearInterval(timer);
+
+            if (statusEl) {
+              statusEl.classList.remove("notice");
+              statusEl.classList.add("warning");
+              statusEl.textContent = "VIN decode timed out. Please refresh or try again.";
+            }
+
+            console.warn("VIN decode polling timed out");
           }
         })
         .catch(err => {
-          console.error("Polling error:", err);
           clearInterval(timer);
+
+          if (statusEl) {
+            statusEl.classList.remove("notice");
+            statusEl.classList.add("error");
+            statusEl.textContent = "Error checking VIN status.";
+          }
+
+          console.error("Polling error:", err);
         });
     };
 

db/migrate/004_add_polling_and_indexes.rb

@@ -8,15 +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 AddIndexes < ActiveRecord::Migration[7.0]
+class AddPollingAndIndexes < ActiveRecord::Migration[7.0]
   
   def change
     add_column :vehicles, :vin_decoded, :boolean, default: false, null: false
+    add_column :vehicles, :error, :string
     add_index :vehicles, :vin_decoded
     add_index :vehicles, :vin, unique: true
     add_index :vehicles, :make
     add_index :vehicles, :model
     add_index :vehicles, :year
+
+    Vehicle.all.each do |v|
+      VehicleVinDecodeJob.perform_later(v.id)
+    end
   end
 
 end