WebMock
Library for stubbing and setting expectations on HTTP requests in Ruby.
Features
- Stubbing HTTP requests at low http client lib level (no need to change tests when you change HTTP library)
- 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
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 request body and headers against regular expressions
stub_request(:post, "www.example.com").
with(:body => /^.*world$/, :headers => {"Content-Type" => /image\/.+/}).to_return(:body => "abc")
uri = URI.parse('https://www.example.com/')
req = Net::HTTP::Post.new(uri.path)
req['Content-Type'] = 'image/png'
res = Net::HTTP.start(uri.host, uri.port) {|http|
http.request(req, 'hello world')
} # ===> Success
Matching custom request headers
stub_request(:any, "www.example.com").with(:headers=>{ 'Header-Name' => 'Header-Value' })
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
Matching requests against provided block
stub_request(:post, "www.example.com").with { |request| request.body == "abc" }
RestClient.post('www.example.com', 'abc') # ===> Success
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
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"
Replaying raw responses recorded with curl -is
`curl -is www.example.com > /tmp/example_curl_-is_output.txt`
raw_response_file = File.new("/tmp/example_curl_-is_output.txt")
from file
stub_request(:get, "www.example.com").to_return(raw_response_file)
or string
stub_request(:get, "www.example.com").to_return(raw_response_file.read)
Custom response with dynamically evaluated response part
stub_request(:any, 'www.example.net').
to_return(:body => lambda { |request| request.body })
RestClient.post('www.example.net', 'abc') # ===> "abc\n"
Custom response with dynamic full response
stub_request(:any, 'www.example.net').
to_return(lambda { |request| {:body => request.body} })
RestClient.post('www.example.net', 'abc') # ===> "abc\n"
Multiple responses for repeated requests
stub_request(:get, "www.example.com").to_return({:body => "abc"}, {:body => "def"})
Net::HTTP.get('www.example.com', '/') # ===> "abc\n"
Net::HTTP.get('www.example.com', '/') # ===> "def\n"
#after all responses are used the last response will be returned infinitely
Net::HTTP.get('www.example.com', '/') # ===> "def\n"
Multiple responses using chained to_return() or to_raise() declarations
stub_request(:get, "www.example.com").
to_return({:body => "abc"}).then. #then() just is a syntactic sugar
to_return({:body => "def"}).then.
to_raise(MyException)
Net::HTTP.get('www.example.com', '/') # ===> "abc\n"
Net::HTTP.get('www.example.com', '/') # ===> "def\n"
Net::HTTP.get('www.example.com', '/') # ===> MyException raised
Specifying number of times given response should be returned
stub_request(:get, "www.example.com").
to_return({:body => "abc"}).times(2).then.
to_return({:body => "def"})
Net::HTTP.get('www.example.com', '/') # ===> "abc\n"
Net::HTTP.get('www.example.com', '/') # ===> "abc\n"
Net::HTTP.get('www.example.com', '/') # ===> "def\n"
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
assert_requested(:post, "https://www.example.com", :times => 1) { |req| req.body == "abc" }
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")
WebMock.should have_requested(:post, "www.example.com").with { |req| req.body == "abc" }
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
request(:post, "www.example.com").with { |req| req.body == "abc" }.should 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
And request matches provided block or block is not provided
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:
-
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' } -
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' } -
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 2009-2010 Bartosz Blimke. See LICENSE for details.