Class: StandardHealth::Generators::InstallGenerator

Inherits:
Rails::Generators::Base
  • Object
show all
Defined in:
lib/generators/standard_health/install/install_generator.rb

Overview

Installs StandardHealth in a host Rails application.

Writes config/initializers/standard_health.rb and mounts the engine in config/routes.rb.

The routes step exists because of a failure mode that is otherwise invisible: the engine only draws SUB-paths (/alive, /ready, /diagnostics/env), so an app that mounts it and expects an aggregate GET /health silently has no aggregate tier — no boot error, no failing route spec. The generated block carries the ordering requirement as a comment right where someone will read it.

Idempotent: re-running skips pieces already installed. --skip-* opts out of individual steps; --force overwrites an existing initializer.

Constant Summary collapse

INITIALIZER_PATH = 
"config/initializers/standard_health.rb"
ROUTES_PATH = 
"config/routes.rb"

Instance Method Summary collapse

Instance Method Details

#copy_initializer ⇒ Object 



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# File 'lib/generators/standard_health/install/install_generator.rb', line 46

def copy_initializer
  if options[:skip_initializer]
    say_status("skip", "#{INITIALIZER_PATH} (--skip-initializer)", :yellow)
    return
  end

  if File.exist?(File.join(destination_root, INITIALIZER_PATH)) && !options[:force]
    say_status("identical", "#{INITIALIZER_PATH} (already exists; pass --force to overwrite)", :blue)
    return
  end

  template "initializer.rb.erb", INITIALIZER_PATH, force: options[:force]
end

#mount_engine ⇒ Object 



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# File 'lib/generators/standard_health/install/install_generator.rb', line 60

def mount_engine
  if options[:skip_routes]
    say_status("skip", "#{ROUTES_PATH} (--skip-routes)", :yellow)
    return
  end

  unless routes_file_exists?
    say_status("skip", "#{ROUTES_PATH} not found; mount the engine manually", :yellow)
    return
  end

  if already_mounted?
    say_status("identical", "#{ROUTES_PATH} (engine already mounted), skipping", :blue)
    return
  end

  route(routes_snippet)

  return unless aggregate_route_drawn?

  # `route` prepends, so a host that already draws its own `GET /health`
  # ends up with the mount ABOVE it. That still WORKS — the engine draws
  # no bare `/health`, so its router returns X-Cascade: pass and the
  # outer route matches (there is a spec pinning this). But it reads
  # backwards against the documented ordering, so say so rather than
  # leaving them to wonder.
  say_status(
    "review",
    "#{ROUTES_PATH}: the mount was prepended ABOVE your existing `GET /health`. " \
    "It still resolves via route cascading, but move the mount below it to match " \
    "the documented ordering.",
    :yellow
  )
end