Dynamic ERB Cassettes

VCR is designed to help you remove all HTTP dependencies from your test suite. To assist with this, VCR will cause an exception to be raised when an HTTP request is made while there is no cassette in use. The error is helpful to pinpoint where HTTP requests are made so you can use a VCR cassette at that point in your code.

If you want insight about how VCR attempted to handle the request, you can use the debug_logger configuration option to log more details.

If you want to allow an HTTP request to proceed as normal, you can set the allow_http_connections_when_no_cassette configuration option or you can temporarily turn VCR off:

  • VCR.turn_off! => turn VCR off so HTTP requests are allowed.

    Cassette insertions will trigger an error.

  • VCR.turn_off!(:ignore_cassettes => true) => turn

    VCR off and ignore cassette insertions (so that no error is raised).

  • VCR.turn_on! => turn VCR back on

  • VCR.turned_off { ... } => turn VCR off for the duration of the

    provided block.

Error for request when no cassette is in use

Given a file named "no_cassette_error.rb" with:

include_http_adapter_for("<http_lib>")

require 'vcr'

VCR.configure do |c|
  <configuration>
  c.cassette_library_dir = 'cassettes'
end

response_body_for(:get, 'http://example.com/')

When I run ruby no_cassette_error.rb

Then it should fail with "An HTTP request has been made that VCR does not know how to handle".

Examples

configuration

http_lib

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 :typhoeus

typhoeus

c.hook_into :excon

excon

c.hook_into :faraday

faraday (w/ net_http)

Temporarily turn VCR off to allow HTTP requests to procede as normal

Given a file named "turn_off_vcr.rb" with:

$server = start_sinatra_app do
  get('/') { 'Hello' }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :webmock
end
WebMock.allow_net_connect!

def make_request(context)
  puts context
  puts Net::HTTP.get_response('localhost', '/', $server.port).body
rescue => e
  puts "Error: #{e.class}"
end

VCR.turned_off do
  make_request "In VCR.turned_off block"
end

make_request "Outside of VCR.turned_off block"

VCR.turn_off!
make_request "After calling VCR.turn_off!"

VCR.turn_on!
make_request "After calling VCR.turn_on!"

When I run ruby turn_off_vcr.rb

Then the output should contain:

In VCR.turned_off block
Hello

And the output should contain:

Outside of VCR.turned_off block
Error: VCR::Errors::UnhandledHTTPRequestError

And the output should contain:

After calling VCR.turn_off!
Hello

And the output should contain:

After calling VCR.turn_on!
Error: VCR::Errors::UnhandledHTTPRequestError

Turning VCR off prevents cassettes from being inserted

Given a file named "turn_off_vcr_and_insert_cassette.rb" with:

require 'vcr'

VCR.configure do |c|
  c.hook_into :webmock
end
WebMock.allow_net_connect!

VCR.turn_off!
VCR.insert_cassette('example')

When I run ruby turn_off_vcr_and_insert_cassette.rb

Then it should fail with "VCR is turned off. You must turn it on before you can insert a cassette.".

Turning VCR off with :ignore_cassettes => true ignores cassettes

Given a file named "turn_off_vcr_and_insert_cassette.rb" with:

$server = start_sinatra_app do
  get('/') { 'Hello' }
end

require 'vcr'

VCR.configure do |c|
  c.cassette_library_dir = 'cassettes'
  c.hook_into :webmock
end
WebMock.allow_net_connect!

VCR.turn_off!(:ignore_cassettes => true)

VCR.use_cassette('example') do
  response = Net::HTTP.get_response('localhost', '/', $server.port).body
  puts "Response: #{response}"
end

When I run ruby turn_off_vcr_and_insert_cassette.rb

Then it should pass with "Response: Hello"

And the file "cassettes/example.yml" should not exist.

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