Plan 03: Favicon Fetch Triggers: Source Creation and Feed Success

Objective

Wire FaviconFetchJob into the source lifecycle: trigger on source creation (controller + OPML import) and on successful feed fetches when favicon is missing. REQ-FAV-03.

Context

• @app/controllers/source_monitor/sources_controller.rb -- create action (lines 54-62) for manual source creation trigger
• @lib/source_monitor/fetching/feed_fetcher/source_updater.rb -- update_source_for_success (lines 14-39) for feed success trigger
• @app/jobs/source_monitor/import_opml_job.rb -- OPML import creates sources in bulk
• @app/jobs/source_monitor/favicon_fetch_job.rb -- the job created in Plan 01 (must exist before this plan executes)

This plan depends on Plan 01 because it references FaviconFetchJob which is created there. No file overlap with Plan 02 (which modifies views/helpers only). This plan modifies: sources_controller.rb, source_updater.rb, import_opml_job.rb, and creates integration tests.

Tasks

Task 1: Trigger favicon fetch on manual source creation

Files: app/controllers/source_monitor/sources_controller.rb

In the create action (line 54-62), after @source.save succeeds but before the redirect, enqueue the favicon job:

Current:

def create
  @source = Source.new(source_params)

  if @source.save
    redirect_to source_monitor.source_path(@source), notice: "Source created successfully"
  else
    render :new, status: :unprocessable_entity
  end
end

Replace with:

def create
  @source = Source.new(source_params)

  if @source.save
    enqueue_favicon_fetch(@source)
    redirect_to source_monitor.source_path(@source), notice: "Source created successfully"
  else
    render :new, status: :unprocessable_entity
  end
end

Add a private method:

def enqueue_favicon_fetch(source)
  return unless defined?(ActiveStorage)
  return unless SourceMonitor.config.favicons.enabled?
  return if source.website_url.blank?

  SourceMonitor::FaviconFetchJob.perform_later(source.id)
rescue StandardError => error
  Rails.logger.warn("[SourceMonitor] Failed to enqueue favicon fetch: #{error.message}") if defined?(Rails) && Rails.respond_to?(:logger) && Rails.logger
end

Tests: test/controllers/source_monitor/sources_controller_favicon_test.rb

Create a separate controller test file to avoid merge conflicts:

• Test create with website_url enqueues FaviconFetchJob (use assert_enqueued_with)
• Test create without website_url does not enqueue FaviconFetchJob
• Test create with favicons disabled does not enqueue FaviconFetchJob
• Test create failure (invalid source) does not enqueue FaviconFetchJob

Task 2: Trigger favicon fetch on successful feed fetch

Files: lib/source_monitor/fetching/feed_fetcher/source_updater.rb

In update_source_for_success (lines 14-39), after source.update!(attributes) on line 39, add favicon fetch enqueue:

Add after source.update!(attributes) (line 39):

enqueue_favicon_fetch_if_needed

Add a private method to the class:

def enqueue_favicon_fetch_if_needed
  return unless defined?(ActiveStorage)
  return unless SourceMonitor.config.favicons.enabled?
  return if source.website_url.blank?
  return if source.respond_to?(:favicon) && source.favicon.attached?

  # Check cooldown via metadata
  last_attempt = source.metadata&.dig("favicon_last_attempted_at")
  if last_attempt.present?
    cooldown_days = SourceMonitor.config.favicons.retry_cooldown_days
    return if Time.parse(last_attempt) > cooldown_days.days.ago
  end

  SourceMonitor::FaviconFetchJob.perform_later(source.id)
rescue StandardError => error
  Rails.logger.warn(
    "[SourceMonitor::SourceUpdater] Failed to enqueue favicon fetch for source #{source.id}: #{error.message}"
  ) if defined?(Rails) && Rails.respond_to?(:logger) && Rails.logger
end

This duplicates some of the cooldown logic from the job itself (belt-and-suspenders). The reason is to avoid enqueuing unnecessary jobs when we can cheaply check in the updater. The job also checks on its own as a safety net.

Tests: test/lib/source_monitor/fetching/feed_fetcher/source_updater_favicon_test.rb

Create a separate test file:

• Test update_source_for_success enqueues FaviconFetchJob when favicon not attached
• Test update_source_for_success does NOT enqueue when favicon already attached
• Test update_source_for_success does NOT enqueue when within cooldown period
• Test update_source_for_success does NOT enqueue when favicons disabled
• Test update_source_for_success does NOT enqueue when website_url blank
• Test update_source_for_success does NOT error when enqueue fails (rescued)
• Test update_source_for_not_modified does NOT enqueue favicon (we only trigger on success with content)

Task 3: Trigger favicon fetch for OPML-imported sources

Files: app/jobs/source_monitor/import_opml_job.rb

Read the existing import_opml_job.rb to understand where sources are created. After each source is successfully created/saved in the import loop, enqueue a favicon fetch.

Find the source creation loop and add after each successful source.save! or source.create!:

SourceMonitor::FaviconFetchJob.perform_later(source.id) if should_fetch_favicon?(source)

Add a private method:

def should_fetch_favicon?(source)
  defined?(ActiveStorage) &&
    SourceMonitor.config.favicons.enabled? &&
    source.website_url.present?
rescue StandardError
  false
end

Tests: test/jobs/source_monitor/import_opml_favicon_test.rb

• Test that OPML import with sources having website_url enqueues FaviconFetchJob for each
• Test that OPML import with sources lacking website_url does not enqueue
• Test that OPML import with favicons disabled does not enqueue

Task 4: Integration test for end-to-end favicon flow

Files: test/integration/source_monitor/favicon_integration_test.rb

Create an integration test that verifies the full flow:

1. Create a source via POST to sources_controller
2. Assert FaviconFetchJob was enqueued
3. Perform the job with WebMock stubs for favicon discovery
4. Assert favicon is attached to the source
5. Verify the source show page renders without error

Use with_queue_adapter(:test) and assert_enqueued_with for job assertions.

Also test the negative path:

• Create source without website_url, verify no job enqueued
• Create source with favicons disabled, verify no job enqueued

Tests: This task IS the test.

Files

Verification

bin/rails test test/controllers/source_monitor/sources_controller_favicon_test.rb test/lib/source_monitor/fetching/feed_fetcher/source_updater_favicon_test.rb test/jobs/source_monitor/import_opml_favicon_test.rb test/integration/source_monitor/favicon_integration_test.rb
bin/rails test test/controllers/source_monitor/sources_controller_test.rb
bin/rubocop app/controllers/source_monitor/sources_controller.rb lib/source_monitor/fetching/feed_fetcher/source_updater.rb app/jobs/source_monitor/import_opml_job.rb

Success Criteria

• Creating a source via UI enqueues FaviconFetchJob when website_url present
• Successful feed fetch enqueues FaviconFetchJob when favicon not attached and outside cooldown
• OPML import enqueues FaviconFetchJob for each imported source with website_url
• All triggers respect the enabled? guard and ActiveStorage check
• All triggers are wrapped in rescue to never break the main flow on failure
• Existing controller, job, and updater tests still pass
• Zero RuboCop offenses