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Project: Vcr 2.2.2

before_record hook

The before_record hook is called before a cassette is written to disk.
This can be used to modify the HTTP interaction before it is recorded.

Your block should accept up to 2 arguments. The first argument will be
the HTTP interaction that is about to be written to disk. The second
argument will be the current cassette.

You can also call #ignore! on the HTTP interaction to prevent VCR
from recording it.

If you don't your hook to apply to all cassettes, you can use tags for
this purpose. Consider this code:

VCR.configure do |c|
  c.before_record(:twitter) { ... } # modify the interactions somehow
end

VCR.use_cassette('cassette_1', :tag => :twitter) { ... }
VCR.use_cassette('cassette_2') { ... }

In this example, the hook would apply to the first cassette but not the
second cassette.

Scenarios
Modify recorded response
Given
a file named "before_record_example.rb" with:
start_sinatra_app(:port => 7777) do
  get('/') { "Hello Earth" }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :fakeweb
  c.cassette_library_dir = 'cassettes'

  c.before_record do |i|
    i.response.body.sub!('Earth', 'World')
  end
end

VCR.use_cassette('recording_example') do
  Net::HTTP.get_response('localhost', '/', 7777)
end
When
I run ruby before_record_example.rb
Then
the file "cassettes/recording_example.yml" should contain "Hello World"
And
the file "cassettes/recording_example.yml" should not contain "Earth"
Modify recorded response based on the cassette
Given
a file named "before_record_example.rb" with:
start_sinatra_app(:port => 7777) do
  get('/') { "Hello Earth" }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :fakeweb
  c.cassette_library_dir = 'cassettes'

  c.before_record do |interaction, cassette|
    interaction.response.body << " (#{cassette.name})"
  end
end

VCR.use_cassette('recording_example') do
  Net::HTTP.get_response('localhost', '/', 7777)
end
When
I run ruby before_record_example.rb
Then
the file "cassettes/recording_example.yml" should contain "Hello Earth (recording_example)"
Prevent recording by ignoring interaction in before_record hook
Given
a file named "before_record_ignore.rb" with:
start_sinatra_app(:port => 7777) do
  get('/') { "Hello World" }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :fakeweb
  c.cassette_library_dir = 'cassettes'
  c.before_record { |i| i.ignore! }
end

VCR.use_cassette('recording_example') do
  response = Net::HTTP.get_response('localhost', '/', 7777)
  puts "Response: #{response.body}"
end
When
I run ruby before_record_ignore.rb
Then
it should pass with "Response: Hello World"
And
the file "cassettes/recording_example.yml" should not exist
Multiple hooks are run in order
Given
a file named "multiple_hooks.rb" with:
start_sinatra_app(:port => 7777) do
  get('/') { "Hello World" }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :fakeweb
  c.cassette_library_dir = 'cassettes'

  c.before_record { puts "In before_record hook 1" }
  c.before_record { puts "In before_record hook 2" }
end

VCR.use_cassette('example', :record => :new_episodes) do
  response = Net::HTTP.get_response('localhost', '/', 7777)
  puts "Response: #{response.body}"
end
When
I run ruby multiple_hooks.rb
Then
it should pass with:
Response: Hello World
In before_record hook 1
In before_record hook 2
Use tagging to apply hook to only certain cassettes
Given
a file named "tagged_hooks.rb" with:
start_sinatra_app(:port => 7777) do
  get('/') { "Hello World" }
end

require 'vcr'

VCR.configure do |c|
  c.hook_into :fakeweb
  c.cassette_library_dir = 'cassettes'

  c.before_record(:tag_1) do
    puts "In before_record hook for tag_1"
  end
end

[:tag_1, :tag_2, nil].each do |tag|
  puts
  puts "Using tag: #{tag.inspect}"

  VCR.use_cassette('example', :record => :new_episodes, :tag => tag) do
    response = Net::HTTP.get_response('localhost', '/', 7777)
    puts "Response: #{response.body}"
  end
end
When
I run ruby tagged_hooks.rb
Then
it should pass with:
Using tag: :tag_1
Response: Hello World
In before_record hook for tag_1

Using tag: :tag_2
Response: Hello World

Using tag: nil
Response: Hello World

Last published about 5 years ago by myronmarston.