module Aws::ClientStubs

This module provides the ability to specify the data and/or errors to return when a client is using stubbed responses. Pass ‘:stub_responses => true` to a client constructor to enable this behavior.

Also allows you to see the requests made by the client by reading the api_requests instance variable

Public Instance Methods

api_requests(options = {}) click to toggle source

Allows you to access all of the requests that the stubbed client has made.

@param [Hash] options The options for the api requests. @option options [Boolean] :exclude_presign (false) Set to true to filter

out unsent requests from generated presigned urls.

@return [Array] Returns an array of the api requests made. Each request

object contains the :operation_name, :params, and :context.

@raise [NotImplementedError] Raises ‘NotImplementedError` when the client

is not stubbed.
# File lib/aws-sdk-core/client_stubs.rb, line 196
def api_requests(options = {})
  if config.stub_responses
    @requests_mutex.synchronize do
      if options[:exclude_presign]
        @api_requests.reject {|req| req[:context][:presigned_url] }
      else
        @api_requests
      end
    end
  else
    msg = 'This method is only implemented for stubbed clients, and is '\
          'available when you enable stubbing in the constructor with `stub_responses: true`'
    raise NotImplementedError.new(msg)
  end
end
next_stub(context) click to toggle source

@api private

# File lib/aws-sdk-core/client_stubs.rb, line 235
def next_stub(context)
  operation_name = context.operation_name.to_sym
  stub = @stub_mutex.synchronize do
    stubs = @stubs[operation_name] || []
    case stubs.length
    when 0 then default_stub(operation_name)
    when 1 then stubs.first
    else stubs.shift
    end
  end
  Proc === stub ? convert_stub(operation_name, stub.call(context)) : stub
end
setup_stubbing() click to toggle source

@api private

# File lib/aws-sdk-core/client_stubs.rb, line 17
def setup_stubbing
  @stubs = {}
  @stub_mutex = Mutex.new
  if Hash === @config.stub_responses
    @config.stub_responses.each do |operation_name, stubs|
      apply_stubs(operation_name, Array === stubs ? stubs : [stubs])
    end
  end

  # When a client is stubbed allow the user to access the requests made
  requests = @api_requests = []
  requests_mutex = @requests_mutex = Mutex.new
  self.handle do |context|
    requests_mutex.synchronize do
      requests << {
        operation_name: context.operation_name,
        params: context.params,
        context: context
      }
    end
    @handler.call(context)
  end
end
stub_data(operation_name, data = {}) click to toggle source

Generates and returns stubbed response data from the named operation.

s3 = Aws::S3::Client.new
s3.stub_data(:list_buckets)
#=> #<struct Aws::S3::Types::ListBucketsOutput buckets=[], owner=#<struct Aws::S3::Types::Owner display_name="DisplayName", id="ID">>

In addition to generating default stubs, you can provide data to apply to the response stub.

s3.stub_data(:list_buckets, buckets:[{name:'aws-sdk'}])
#=> #<struct Aws::S3::Types::ListBucketsOutput
  buckets=[#<struct Aws::S3::Types::Bucket name="aws-sdk", creation_date=nil>],
  owner=#<struct Aws::S3::Types::Owner display_name="DisplayName", id="ID">>

@param [Symbol] operation_name @param [Hash] data @return [Structure] Returns a stubbed response data structure. The

actual class returned will depend on the given `operation_name`.
# File lib/aws-sdk-core/client_stubs.rb, line 230
def stub_data(operation_name, data = {})
  Stubbing::StubData.new(config.api.operation(operation_name)).stub(data)
end
stub_responses(operation_name, *stubs) click to toggle source

Configures what data / errors should be returned from the named operation when response stubbing is enabled.

## Basic usage

When you enable response stubbing, the client will generate fake responses and will not make any HTTP requests.

client = Aws::S3::Client.new(stub_responses: true)
client.list_buckets
#=> #<struct Aws::S3::Types::ListBucketsOutput buckets=[], owner=nil>

You can provide stub data that will be returned by the client.

# stub data in the constructor
client = Aws::S3::Client.new(stub_responses: {
  list_buckets: { buckets: [{name: 'my-bucket' }] },
  get_object: { body: 'data' },
})

client.list_buckets.buckets.map(&:name) #=> ['my-bucket']
client.get_object(bucket:'name', key:'key').body.read #=> 'data'

You can also specify the stub data using {#stub_responses}

client = Aws::S3::Client.new(stub_responses: true)
client.stub_responses(:list_buckets, {
  buckets: [{ name: 'my-bucket' }]
})

client.list_buckets.buckets.map(&:name)
#=> ['my-bucket']

With a Resource class {#stub_responses} on the corresponding client:

s3 = Aws::S3::Resource.new(stub_responses: true)
s3.client.stub_responses(:list_buckets, {
  buckets: [{ name: 'my-bucket' }]
})

s3.buckets.map(&:name)
#=> ['my-bucket']

Lastly, default stubs can be configured via ‘Aws.config`:

Aws.config[:s3] = {
  stub_responses: {
    list_buckets: { buckets: [{name: 'my-bucket' }] }
  }
}

Aws::S3::Client.new.list_buckets.buckets.map(&:name)
#=> ['my-bucket']

Aws::S3::Resource.new.buckets.map(&:name)
#=> ['my-bucket']

## Dynamic Stubbing

In addition to creating static stubs, it’s also possible to generate stubs dynamically based on the parameters with which operations were called, by passing a ‘Proc` object:

s3 = Aws::S3::Resource.new(stub_responses: true)
s3.client.stub_responses(:put_object, -> (context) {
  s3.client.stub_responses(:get_object, content_type: context.params[:content_type])
})

The yielded object is an instance of {Seahorse::Client::RequestContext}.

## Stubbing Errors

When stubbing is enabled, the SDK will default to generate fake responses with placeholder values. You can override the data returned. You can also specify errors it should raise.

# simulate service errors, give the error code
client.stub_responses(:get_object, 'NotFound')
client.get_object(bucket:'aws-sdk', key:'foo')
#=> raises Aws::S3::Errors::NotFound

# to simulate other errors, give the error class, you must
# be able to construct an instance with `.new`
client.stub_responses(:get_object, Timeout::Error)
client.get_object(bucket:'aws-sdk', key:'foo')
#=> raises new Timeout::Error

# or you can give an instance of an error class
client.stub_responses(:get_object, RuntimeError.new('custom message'))
client.get_object(bucket:'aws-sdk', key:'foo')
#=> raises the given runtime error object

## Stubbing HTTP Responses

As an alternative to providing the response data, you can provide an HTTP response.

client.stub_responses(:get_object, {
  status_code: 200,
  headers: { 'header-name' => 'header-value' },
  body: "...",
})

To stub a HTTP response, pass a Hash with all three of the following keys set:

  • **‘:status_code`** - <Integer> - The HTTP status code

  • **‘:headers`** - Hash<String,String> - A hash of HTTP header keys and values

  • **‘:body`** - <String,IO> - The HTTP response body.

## Stubbing Multiple Responses

Calling an operation multiple times will return similar responses. You can configure multiple stubs and they will be returned in sequence.

client.stub_responses(:head_object, [
  'NotFound',
  { content_length: 150 },
])

client.head_object(bucket:'aws-sdk', key:'foo')
#=> raises Aws::S3::Errors::NotFound

resp = client.head_object(bucket:'aws-sdk', key:'foo')
resp.content_length #=> 150

@param [Symbol] operation_name

@param [Mixed] stubs One or more responses to return from the named

operation.

@return [void]

@raise [RuntimeError] Raises a runtime error when called

on a client that has not enabled response stubbing via
`:stub_responses => true`.
# File lib/aws-sdk-core/client_stubs.rb, line 177
def stub_responses(operation_name, *stubs)
  if config.stub_responses
    apply_stubs(operation_name, stubs.flatten)
  else
    msg = 'stubbing is not enabled; enable stubbing in the constructor '\
          'with `:stub_responses => true`'
    raise msg
  end
end

Private Instance Methods

apply_stubs(operation_name, stubs) click to toggle source

This method converts the given stub data and converts it to a HTTP response (when possible). This enables the response stubbing plugin to provide a HTTP response that triggers all normal events during response handling.

# File lib/aws-sdk-core/client_stubs.rb, line 259
def apply_stubs(operation_name, stubs)
  @stub_mutex.synchronize do
    @stubs[operation_name.to_sym] = stubs.map do |stub|
      convert_stub(operation_name, stub)
    end
  end
end
convert_stub(operation_name, stub) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 267
def convert_stub(operation_name, stub)
  stub = case stub
  when Proc then stub
  when Exception, Class then { error: stub }
  when String then service_error_stub(stub)
  when Hash then http_response_stub(operation_name, stub)
  else { data: stub }
  end
  if Hash === stub
    stub[:mutex] = Mutex.new
  end
  stub
end
data_to_http_resp(operation_name, data) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 301
def data_to_http_resp(operation_name, data)
  api = config.api
  operation = api.operation(operation_name)
  ParamValidator.new(operation.output, input: false).validate!(data)
  protocol_helper.stub_data(api, operation, data)
end
default_stub(operation_name) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 250
def default_stub(operation_name)
  stub = stub_data(operation_name)
  http_response_stub(operation_name, stub)
end
hash_to_http_resp(data) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 293
def hash_to_http_resp(data)
  http_resp = Seahorse::Client::Http::Response.new
  http_resp.status_code = data[:status_code]
  http_resp.headers.update(data[:headers])
  http_resp.body = data[:body]
  http_resp
end
http_response_stub(operation_name, data) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 285
def http_response_stub(operation_name, data)
  if Hash === data && data.keys.sort == [:body, :headers, :status_code]
    { http: hash_to_http_resp(data) }
  else
    { http: data_to_http_resp(operation_name, data) }
  end
end
protocol_helper() click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 308
def protocol_helper
  case config.api.metadata['protocol']
  when 'json'               then Stubbing::Protocols::Json
  when 'rest-json'          then Stubbing::Protocols::RestJson
  when 'rest-xml'           then Stubbing::Protocols::RestXml
  when 'query'              then Stubbing::Protocols::Query
  when 'ec2'                then Stubbing::Protocols::EC2
  when 'smithy-rpc-v2-cbor' then Stubbing::Protocols::RpcV2
  when 'api-gateway'        then Stubbing::Protocols::ApiGateway
  else raise 'unsupported protocol'
  end.new
end
service_error_stub(error_code) click to toggle source
# File lib/aws-sdk-core/client_stubs.rb, line 281
def service_error_stub(error_code)
  { http: protocol_helper.stub_error(error_code) }
end