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|
# frozen_string_literal: true
require "action_dispatch"
require "json"
module Labkit
module Middleware
HEADER = "X-Gitlab-Meta"
# This is a rack middleware to be inserted in GitLab-rails
# It makes sure that there's always a root context containing the correlation
# id.
# Since this context always get's cleaned up by this middleware, we can be
# sure that any nested contexts will also be cleaned up.
class Rack
def initialize(app)
@app = app
end
def call(env)
Labkit::Context.with_context(Labkit::Context::CORRELATION_ID_KEY => correlation_id(env)) do |context|
status, headers, response = @app.call(env)
headers[HEADER] = context_to_json(context)
[status, headers, response]
end
end
private
def correlation_id(env)
request(env).request_id
end
def request(env)
ActionDispatch::Request.new(env)
end
def context_to_json(context)
context
.to_h
.transform_keys { |k| k.delete_prefix("meta.") }
.merge("version" => "1")
.to_json
end
end
end
end
|
