Class: ActionDispatch::RequestId
- Defined in:
- actionpack/lib/action_dispatch/middleware/request_id.rb
Overview
Makes a unique request id available to the action_dispatch.request_id
env variable (which is then accessible through ActionDispatch::Request#request_id or the alias ActionDispatch::Request#uuid) and sends the same id to the client via the X-Request-Id
header.
The unique request id is either based on the X-Request-Id
header in the request, which would typically be generated by a firewall, load balancer, or the web server, or, if this header is not available, a random uuid. If the header is accepted from the outside world, we sanitize it to a max of 255 chars and alphanumeric and dashes only.
The unique request id can be used to trace a request end-to-end and would typically end up being part of log files from multiple pieces of the stack.
Instance Method Summary collapse
- #call(env) ⇒ Object
-
#initialize(app, header:) ⇒ RequestId
constructor
A new instance of RequestId.
Constructor Details
#initialize(app, header:) ⇒ RequestId
Returns a new instance of RequestId.
18 19 20 21 |
# File 'actionpack/lib/action_dispatch/middleware/request_id.rb', line 18 def initialize(app, header:) @app = app @header = header end |
Instance Method Details
#call(env) ⇒ Object
23 24 25 26 27 |
# File 'actionpack/lib/action_dispatch/middleware/request_id.rb', line 23 def call(env) req = ActionDispatch::Request.new env req.request_id = make_request_id(req.headers[@header]) @app.call(env).tap { |_status, headers, _body| headers[@header] = req.request_id } end |