Project: Vcr 2.4.0

Publisher: VCR

hook_into

The hook_into configuration option determines how VCR hooks into the
HTTP requests to record and replay them. There are currently 4 valid
options which support many different HTTP libraries:

:fakeweb can be used to hook into Net::HTTP requests.
:webmock can be used to hook into requests from:
- Net::HTTP
- HTTPClient
- Patron
- Curb (Curl::Easy, but not Curl::Multi)
- EM HTTP Request
- Typhoeus (Typhoeus::Hydra, but not Typhoeus::Easy or Typhoeus::Multi)
- Excon
:typhoeus can be used to hook into itself (as long as you use Typhoeus::Hydra, but not Typhoeus::Easy or Typhoeus::Multi).
:excon can be used to hook into itself.
:faraday can be used to hook into itself.

There are some addiitonal trade offs to consider when deciding which
option to use:

FakeWeb is currently about 4 times faster than WebMock for hooking into Net::HTTP (see benchmarks/http_stubbing_libraries.rb for details).
FakeWeb and WebMock both use extensive monkey patching to hook into their supported HTTP libraries. No monkey patching is used for Typhoeus, Excon or Faraday.
FakeWeb and WebMock cannot both be used at the same time.
Typhoeus, Excon, Faraday can be used together, and with either FakeWeb or WebMock.

Regardless of which library you use, VCR takes care of all of the configuration
for you. You should not need to interact directly with FakeWeb, WebMock or the
stubbing facilities of Typhoeus, Excon or Faraday. If/when you decide to change stubbing
libraries (i.e. if you initially use FakeWeb because it's faster but later need the
additional features of WebMock) you can change the hook_into configuration
option and it'll work with no other changes required.

Scenarios

Record and replay a request using each supported hook_into/http library combination

Given

a file named "hook_into_http_lib_combo.rb" with:

include_http_adapter_for("http_lib")

require 'vcr'
VCR.configure { |c| c.ignore_localhost = true }

start_sinatra_app(:port => 7777) do
  get('/') { ARGV[0] }
end

puts "The response for request 1 was: #{response_body_for(:get, "http://localhost:7777/")}"

VCR.configure do |c|
  configuration
  c.cassette_library_dir = 'vcr_cassettes'
  c.ignore_localhost = false
  c.default_cassette_options = { :serialize_with => :syck }
end

VCR.use_cassette('example') do
  puts "The response for request 2 was: #{response_body_for(:get, "http://localhost:7777/")}"
end

When

I run ruby hook_into_http_lib_combo.rb 'Hello World'

Then

the output should contain each of the following:

The response for request 1 was: Hello World

The response for request 2 was: Hello World

And

the file "vcr_cassettes/example.yml" should contain "Hello World"

When

I run ruby hook_into_http_lib_combo.rb 'Goodbye World'

Then

the output should contain each of the following:

The response for request 1 was: Goodbye World

The response for request 2 was: Hello World

And

the file "vcr_cassettes/example.yml" should contain "Hello World"

Examples:
configuration	http_lib
c.hook_into :fakeweb	net/http
c.hook_into :webmock	net/http
c.hook_into :webmock	httpclient
c.hook_into :webmock	curb
c.hook_into :webmock	patron
c.hook_into :webmock	em-http-request
c.hook_into :webmock	typhoeus
c.hook_into :webmock	excon
c.hook_into :typhoeus	typhoeus
c.hook_into :excon	excon
c.hook_into :faraday	faraday (w/ net_http)
c.hook_into :faraday	faraday (w/ typhoeus)

@exclude-jruby @exclude-18 Use Typhoeus, Excon and Faraday in combination with FakeWeb or WebMock

Given

a file named "hook_into_multiple.rb" with:

require 'typhoeus'
require 'excon'
require 'faraday'
require 'vcr'
extra_require

VCR.configure { |c| c.ignore_localhost = true }

start_sinatra_app(:port => 7777) do
  get('/:path') { "#{ARGV[0]} #{params[:path]}" }
end

def net_http_response
  Net::HTTP.get_response('localhost', '/net_http', 7777).body
end

def typhoeus_response
  Typhoeus::Request.get("http://localhost:7777/typhoeus").body
end

def excon_response
  Excon.get("http://localhost:7777/excon").body
end

def faraday_response
  Faraday::Connection.new(:url => 'http://localhost:7777') do |builder|
    builder.adapter :faraday_adapter
  end.get('/faraday').body
end

puts "Net::HTTP 1: #{net_http_response}"
puts "Typhoeus 1: #{typhoeus_response}"
puts "Excon 1: #{excon_response}"
puts "Faraday 1: #{faraday_response}"

VCR.configure do |c|
  c.hook_into hook_into, :typhoeus, :excon, :faraday
  c.cassette_library_dir = 'vcr_cassettes'
  c.ignore_localhost = false
end

VCR.use_cassette('example') do
  puts "Net::HTTP 2: #{net_http_response}"
  puts "Typhoeus 2: #{typhoeus_response}"
  puts "Excon 2: #{excon_response}"
  puts "Faraday 2: #{faraday_response}"
end

When

I run ruby hook_into_multiple.rb 'Hello'

Then

the output should contain each of the following:

Net::HTTP 1: Hello net_http

Typhoeus 1: Hello typhoeus

Excon 1: Hello excon

Faraday 1: Hello faraday

Net::HTTP 2: Hello net_http

Typhoeus 2: Hello typhoeus

Excon 2: Hello excon

Faraday 2: Hello faraday

And

the cassette "vcr_cassettes/example.yml" should have the following response bodies:

Hello net_http

Hello typhoeus

Hello excon

Hello faraday

When

I run ruby hook_into_multiple.rb 'Goodbye'

Then

the output should contain each of the following:

Net::HTTP 1: Goodbye net_http

Typhoeus 1: Goodbye typhoeus

Excon 1: Goodbye excon

Faraday 1: Goodbye faraday

Net::HTTP 2: Hello net_http

Typhoeus 2: Hello typhoeus

Excon 2: Hello excon

Faraday 2: Hello faraday

Examples:
hook_into	faraday_adapter	extra_require
:fakeweb	net_http
:webmock	net_http
:fakeweb	typhoeus	require 'typhoeus/adapters/faraday'
:webmock	typhoeus	require 'typhoeus/adapters/faraday'

Last published about 6 years ago by myronmarston.

hook_into

Vcr settings