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Project: Vcr 2.8.0

Publisher: VCR

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
  1. Modify recorded response
  2. Modify recorded response based on the cassette
  3. Prevent recording by ignoring interaction in before_record hook
  4. Multiple hooks are run in order
  5. Use tagging to apply hook to only certain cassettes
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 :webmock
  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 :webmock
  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 :webmock
  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 :webmock
  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 :webmock
  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.