fix(pwa): serve manifest for html accept headers (#1828)

* fix(pwa): serve manifest for html accept headers

* style: add trailing newline to pwa controller

app/controllers/pwa_controller.rb

@@ -0,0 +1,15 @@
+class PwaController < ApplicationController
+  skip_authentication
+
+  def manifest
+    # Force JSON format to avoid MissingTemplate errors when browsers request /manifest
+    # with HTML Accept headers (Safari Mobile does this for PWA manifest discovery)
+    render "pwa/manifest", content_type: "application/manifest+json"
+  end
+
+  def service_worker
+    # Explicitly render JS template to avoid format negotiation issues
+    render "pwa/service-worker", content_type: "application/javascript"
+  end
+  # Renders app/views/pwa/service-worker.js with content type application/javascript
+end

config/routes.rb

@@ -641,8 +641,8 @@ Rails.application.routes.draw do
   get "up" => "rails/health#show", as: :rails_health_check
 
   # Render dynamic PWA files from app/views/pwa/*
-  get "service-worker" => "rails/pwa#service_worker", as: :pwa_service_worker
-  get "manifest" => "rails/pwa#manifest", as: :pwa_manifest
+  get "service-worker" => "pwa#service_worker", as: :pwa_service_worker, defaults: { format: :js }
+  get "manifest" => "pwa#manifest", as: :pwa_manifest, defaults: { format: :json }
 
   get "imports/:import_id/upload/sample_csv", to: "import/uploads#sample_csv", as: :import_upload_sample_csv
 

test/controllers/pwa_controller_test.rb

@@ -0,0 +1,11 @@
+require "test_helper"
+
+class PwaControllerTest < ActionDispatch::IntegrationTest
+  test "manifest responds successfully for html accept headers" do
+    get "/manifest", headers: { "Accept" => "text/html" }
+
+    assert_response :success
+    assert_equal "application/manifest+json", response.media_type
+    assert_includes response.body, '"start_url": "/"'
+  end
+end