Pact Consumer Swift

• Core Library build:
• Swift, Carthage Example build:
• ObjeciveC, Git Submodules Example build:

This library provides a Swift / Objective C DSL for creating Consumer Pacts.

Implements Pact Specification v2, including flexible matching.

This DSL relies on the Ruby pact-mock_service gem to provide the mock service for the tests.

Installation

Note: see Upgrading for notes on upgrading from 0.2 to 0.3

Install the pact-mock_service

gem install pact-mock_service -v 0.9.0

Add the PactConsumerSwift library to your project

Using Carthage library manager

• See the PactSwiftExample for an example project using the library with Carthage.

Using CocoaPods

• See the PactObjectiveCExample for an example project using the library with CocoaPods.

Writing Pact Tests

Testing with Swift

Write a Unit test similar to the following (NB: this example is using the Quick test framework)

import PactConsumerSwift

...
  beforeEach {
    animalMockService = MockService(provider: "Animal Service", consumer: "Animal Consumer Swift")
    animalServiceClient = AnimalServiceClient(baseUrl: animalMockService!.baseUrl)
  }

  it("gets an alligator") {
    animalMockService!.given("an alligator exists")
                      .uponReceiving("a request for an alligator")
                      .withRequest(method:.GET, path: "/alligator")
                      .willRespondWith(status:200,
                                       headers: ["Content-Type": "application/json"],
                                       body: ["name": "Mary"])

    //Run the tests
    animalMockService!.run { (testComplete) -> Void in
      animalServiceClient!.getAlligator { (alligator) in
        expect(alligator.name).to(equal("Mary"))
        testComplete()
      }
    }
  }

Testing with Objective-C

Write a Unit test similar to the following

@import PactConsumerSwift;
...
- (void)setUp {
  [super setUp];
  self.animalMockService = [[MockService alloc] initWithProvider:@"Animal Provider"
                                                        consumer:@"Animal Service Client Objective-C"];
  self.animalServiceClient = [[OCAnimalServiceClient alloc] initWithBaseUrl:self.animalMockService.baseUrl];
}

- (void)testGetAlligator {
  typedef void (^CompleteBlock)();

  [[[[self.animalMockService given:@"an alligator exists"]
                             uponReceiving:@"oc a request for an alligator"]
                             withRequestHTTPMethod:PactHTTPMethodGET
                                              path:@"/alligator"
                                             query:nil headers:nil body:nil]
                             willRespondWithHTTPStatus:200
                                               headers:@{@"Content-Type": @"application/json"}
                                                  body: @"{ \"name\": \"Mary\"}" ];

  [self.animalMockService run:^(CompleteBlock testComplete) {
      Animal *animal = [self.animalServiceClient getAlligator];
      XCTAssertEqualObjects(animal.name, @"Mary");
      testComplete();
  }];
}

Matching

In addition to verbatim value matching, you have 3 useful matching functions in the Matcher class that can increase expressiveness and reduce brittle test cases.

• Matcher.term(matcher, generate) - tells Pact that the value should match using a given regular expression, using generate in mock responses. generate must be a string.
• Matcher.somethingLike(content) - tells Pact that the value itself is not important, as long as the element type (valid JSON number, string, object etc.) itself matches.
• Matcher.eachLike(content, min) - tells Pact that the value should be an array type, consisting of elements like those passed in. min must be >= 1. content may be a valid JSON value: e.g. strings, numbers and objects.

NOTE: One caveat to note, is that you will need to use valid Ruby regular expressions and double escape backslashes.

See the PactSpecs.swift, PactObjectiveCTests.m for examples on how to expect error responses, how to use query params, and the Matchers.

For more on request / response matching, see Matching.

Verifying your iOS client against the service you are integrating with

If your setup is correct and your tests run against the pack mock server, then you should see a log file here: $YOUR_PROJECT/tmp/pact.log And the generated pacts, here: $YOUR_PROJECT/tmp/pacts/...

See Verifying pacts for more information.

For an end to end example with a ruby back end service, have a look at the KatKit example. Here is an article using a dockerized nodejs service which uses provider states.

More reading

• The Pact website Pact
• The pact mock server that the Swift library uses under the hood Pact mock service
• A pact broker for managing the generated pact files (so you don't have to manually copy them around!) Pact broker

Contributing

Please read CONTRIBUTING.md