WebMock

Library for stubbing HTTP requests and setting expectations on HTTP requests in Ruby.

Features

• Stubbing HTTP requests at low Net::HTTP level (no need to change tests when you change HTTP lib interface)
• Setting and verifying expectations on HTTP requests
• Matching requests based on method, URI, headers and body
• Smart matching of the same URIs in different representations (also encoded and non encoded forms)
• Smart matching of the same headers in different representations.
• Support for Test::Unit and RSpec (and can be easily extended to other frameworks)
• Support for Net::HTTP and other http libraries based on Net::HTTP (i.e RightHttpConnection, rest-client, HTTParty)
• Support for HTTPClient library (both sync and async requests)
• Easy to extend to other HTTP libraries except Net::HTTP

Installation

gem install webmock --source https://gemcutter.org

In your test/test_helper.rb add these two lines:

require 'webmock/test_unit'
include WebMock

or if you use RSpec add these lines to spec/spec_helper:

require 'webmock/rspec'
include WebMock

You can also use WebMock without RSpec or Test::Unit support:

require 'webmock'
include WebMock

Examples

Stubbing

Stubbed request based on uri only and with the default response

 stub_request(:any, "www.example.com")
 Net::HTTP.get("www.example.com", "/")    # ===> Success

Stubbing requests based on method, uri, body and headers

stub_request(:post, "www.example.com").with(:body => "abc", :headers => { 'Content-Length' => 3 })
uri = URI.parse("https://www.example.com/")
req = Net::HTTP::Post.new(uri.path)
req['Content-Length'] = 3
res = Net::HTTP.start(uri.host, uri.port) {|http|
  http.request(req, "abc")
}    # ===> Success

Matching custom request headers

stub_request(:any, "www.example.com").
  with( :headers=>{ 'Header-Name' => 'Header-Value' } ).to_return(:body => "abc", :status => 200)
uri = URI.parse('https://www.example.com/')
req = Net::HTTP::Post.new(uri.path)
req['Header-Name'] = 'Header-Value'
res = Net::HTTP.start(uri.host, uri.port) {|http|
  http.request(req, 'abc')
}    # ===> Success

Stubbing with custom response

stub_request(:any, "www.example.com").to_return(:body => "abc", :status => 200,  :headers => { 'Content-Length' => 3 } )
Net::HTTP.get("www.example.com", '/')    # ===> "abc"

Custom response with body specified as IO object

File.open('/tmp/response_body.txt', 'w') { |f| f.puts 'abc' }
stub_request(:any, "www.example.com").to_return(:body => File.new('/tmp/response_body.txt'), :status => 200)
Net::HTTP.get('www.example.com', '/')    # ===> "abc\n"

Custom response with dynamically evaluated response

stub_request(:any, 'www.example.net').
  to_return(:body => lambda { |request| request.body })
RestClient.post('www.example.net', 'abc')    # ===> "abc\n" 

Request with basic authentication

stub_request(:get, "user:pass@www.example.com")
Net::HTTP.start('www.example.com') {|http|
  req = Net::HTTP::Get.new('/')
  req.basic_auth 'user', 'pass'
  http.request(req)
}  # ===> Success

Matching uris using regular expressions

 stub_request(:any, /.*example.*/)
 Net::HTTP.get('www.example.com', '/') # ===> Success

Real requests to network can be allowed or disabled

WebMock.allow_net_connect!
stub_request(:any, "www.example.com").to_return(:body => "abc")
Net::HTTP.get('www.example.com', '/')    # ===> "abc"
Net::HTTP.get('www.something.com', '/') # ===> /.+Something.+/
WebMock.disable_net_connect!
Net::HTTP.get('www.something.com', '/')    # ===> Failure

Setting Expectations

Setting expectations in Test::Unit

require 'webmock/test_unit'
stub_request(:any, "www.example.com")
uri = URI.parse('https://www.example.com/')
req = Net::HTTP::Post.new(uri.path)
req['Content-Length'] = 3
res = Net::HTTP.start(uri.host, uri.port) {|http|
  http.request(req, 'abc')
}
assert_requested :post, "https://www.example.com",
  :headers => {'Content-Length' => 3}, :body => "abc", :times => 1    # ===> Success
assert_not_requested :get, "https://www.something.com"    # ===> Success

Expecting real (not stubbed) requests

WebMock.allow_net_connect!
Net::HTTP.get('www.example.com', '/')    # ===> Success
assert_requested :get, "https://www.example.com"    # ===> Success

Setting expectations in RSpec

This style is borrowed from fakeweb-matcher

require 'webmock/rspec'
WebMock.should have_requested(:get, "www.example.com").with(:body => "abc", :headers => {'Content-Length' => 3}).twice
WebMock.should_not have_requested(:get, "www.something.com")

Different way of setting expectations in RSpec

request(:post, "www.example.com").with(:body => "abc", :headers => {'Content-Length' => 3}).should have_been_made.once
request(:post, "www.something.com").should have_been_made.times(3)
request(:any, "www.example.com").should_not have_been_made

Clearing stubs and request history

If you want to reset all current stubs and history of requests use WebMock.reset_webmock

stub_request(:any, "www.example.com")
Net::HTTP.get('www.example.com', '/')    # ===> Success
reset_webmock
Net::HTTP.get('www.example.com', '/')    # ===> Failure
assert_not_requested :get, "www.example.com"    # ===> Success

Matching requests

An executed request matches stubbed request if it passes following criteria:

When request URI matches stubbed request URI string or Regexp pattern
And request method is the same as stubbed request method or stubbed request method is :any
And request body is the same as stubbed request body or stubbed request body is not specified
And request headers match stubbed request headers, or stubbed request headers match a subset of request headers, or stubbed request headers are not specified

Precedence of stubs

Always the last declared stub matching the request will be applied i.e:

stub_request(:get, "www.example.com").to_return(:body => "abc")
stub_request(:get, "www.example.com").to_return(:body => "def")
Net::HTTP.get('www.example.com', '/')   # ====> "def"

Matching URIs

WebMock will match all different representations of the same URI.

I.e all the following representations of the URI are equal:

"www.example.com"
"www.example.com/"
"www.example.com:80"
"www.example.com:80/"
"https://www.example.com"
"https://www.example.com/"
"https://www.example.com:80"
"https://www.example.com:80/"

The following URIs with basic authentication are also equal for WebMock

"a b:pass@www.example.com"
"a b:pass@www.example.com/"
"a b:pass@www.example.com:80"
"a b:pass@www.example.com:80/"
"https://a b:pass@www.example.com"
"https://a b:pass@www.example.com/"
"https://a b:pass@www.example.com:80"
"https://a b:pass@www.example.com:80/"
"a%20b:pass@www.example.com"
"a%20b:pass@www.example.com/"
"a%20b:pass@www.example.com:80"
"a%20b:pass@www.example.com:80/"
"https://a%20b:pass@www.example.com"
"https://a%20b:pass@www.example.com/"
"https://a%20b:pass@www.example.com:80"
"https://a%20b:pass@www.example.com:80/" 

or these

"www.example.com/my path/?a=my param&b=c"
"www.example.com/my%20path/?a=my%20param&b=c"
"www.example.com:80/my path/?a=my param&b=c"
"www.example.com:80/my%20path/?a=my%20param&b=c"
"https://www.example.com/my path/?a=my param&b=c"
"https://www.example.com/my%20path/?a=my%20param&b=c"
"https://www.example.com:80/my path/?a=my param&b=c"
"https://www.example.com:80/my%20path/?a=my%20param&b=c"

If you provide Regexp to match URI, WebMock will try to match it against every valid form of the same url.

I.e /.*my param.*/ will match www.example.com/my%20path because it is equivalent of www.example.com/my path

Matching headers

WebMock will match request headers against stubbed request headers in the following situations:

1. Stubbed request has headers specified and request headers are the same as stubbed headers
   i.e stubbed headers: { 'Header1' => 'Value1', 'Header1' => 'Value1' }, requested: { 'Header1' => 'Value1', 'Header1' => 'Value1' }

2. Stubbed request has headers specified and stubbed request headers are a subset of request headers
   i.e stubbed headers: { 'Header1' => 'Value1' }, requested: { 'Header1' => 'Value1', 'Header1' => 'Value1' }

3. Stubbed request has no headers
   i.e stubbed headers: nil, requested: { 'Header1' => 'Value1', 'Header1' => 'Value1' }

WebMock normalises headers and treats all forms of same headers as equal: i.e the following two sets of headers are equal:

{ "Header1" => "value1", :content_length => 123, :X_CuStOm_hEAder => :value }

{ :header1 => "value1", "Content-Length" => 123, "x-cuSTOM-HeAder" => "value" }

Bugs and Issues

Please submit them here https://github.com/bblimke/webmock/issues

Suggestions

If you have any suggestions on how to improve WebMock please send an email to the mailing list groups.google.com/group/webmock-users

I'm particularly interested in how the DSL could be improved.

Credits

Thanks to my fellow Bambinos for all the great suggestions!

Thank you Fakeweb! This library was inspired by FakeWeb. I took couple of solutions from that project. I also copied some code i.e Net:HTTP adapter. Fakeweb architecture unfortunately didn't allow me to extend it easily with the features I needed. I also preferred some things to work differently i.e request stub precedence.

Copyright

Copyright 2009 Bartosz Blimke. See LICENSE for details.