feat: Enable gzip support for event payloads

contract-tests/service.rb

@@ -34,6 +34,7 @@
  'secure-mode-hash',
  'tags',
  'migrations',
+ 'event-gzip',
  'event-sampling',
  'context-comparison',
  'polling-gzip',

launchdarkly-server-sdk.gemspec

@@ -38,6 +38,7 @@ Gem::Specification.new do |spec|
  spec.add_runtime_dependency "semantic", "~> 1.6"
  spec.add_runtime_dependency "concurrent-ruby", "~> 1.1"
  spec.add_runtime_dependency "ld-eventsource", "2.2.2"
+ spec.add_runtime_dependency "zlib", "~> 3.1"
  # Please keep ld-eventsource dependency as an exact version so that bugfixes to
  # that LD library are always associated with a new SDK version.
 

lib/ldclient-rb/impl/event_sender.rb

@@ -2,6 +2,8 @@
 
 require "securerandom"
 require "http"
+require "stringio"
+require "zlib"
 
 module LaunchDarkly
  module Impl
@@ -42,14 +44,17 @@ def send_event_data(event_data, description, is_diagnostic)
  @logger.debug { "[LDClient] sending #{description}: #{event_data}" }
  headers = {}
  headers["content-type"] = "application/json"
+ headers["content-encoding"] = "gzip"
  Impl::Util.default_http_headers(@sdk_key, @config).each { |k, v| headers[k] = v }
  unless is_diagnostic
  headers["X-LaunchDarkly-Event-Schema"] = CURRENT_SCHEMA_VERSION.to_s
  headers["X-LaunchDarkly-Payload-ID"] = payload_id
  end
+ gzip = Zlib::GzipWriter.new(StringIO.new)
+ gzip << event_data
  response = http_client.request("POST", uri, {
  headers: headers,
- body: event_data,
+ body: gzip.close.string,
  })
  rescue StandardError => exn
  @logger.warn { "[LDClient] Error sending events: #{exn.inspect}." }

spec/http_util.rb

@@ -1,6 +1,8 @@
 require "webrick"
 require "webrick/httpproxy"
 require "webrick/https"
+require "stringio"
+require "zlib"
 
 class StubHTTPServer
  attr_reader :requests, :port
@@ -73,14 +75,13 @@ def record_request(req, res)
  @requests_queue << [req, req.body]
  end
 
- def await_request
- r = @requests_queue.pop
- r[0]
- end
-
  def await_request_with_body
  r = @requests_queue.pop
- [r[0], r[1]]
+ body = r[1]
+
+ gz = Zlib::GzipReader.new(StringIO.new(body.to_s))
+
+ [r[0], gz.read]
  end
 end
 

spec/impl/event_sender_spec.rb

@@ -37,8 +37,8 @@ def with_sender_and_server
  expect(result.must_shutdown).to be false
  expect(result.time_from_server).not_to be_nil
 
- req = server.await_request
- expect(req.body).to eq fake_data
+ req, body = server.await_request_with_body
+ expect(body).to eq fake_data
  expect(req.header).to include({
  "authorization" => [ sdk_key ],
  "content-type" => [ "application/json" ],
@@ -63,8 +63,8 @@ def with_sender_and_server
  result = es.send_event_data(fake_data, "", false)
 
  expect(result.success).to be true
- req = server.await_request
- expect(req.body).to eq fake_data
+ req, body = server.await_request_with_body
+ expect(body).to eq fake_data
  expect(req.host).to eq "fake-event-server"
  end
  end