pact_dart

Description:

pact dart

pact_dart #


Pact is a contract testing tool to help you replace expensive and brittle end-to-end integration tests with fast, reliable and easy to debug unit tests. This framework provides a Dart DSL for generating Pact contracts. It implements Pact Specification v3 using the Pact FFI Library.
Documentation #
This readme offers an basic introduction to the library. View more documentation on Pact at https://docs.pact.io/.

Installation
Basic Usage
Consumer Documentation

Need Help #

Join our community slack workspace.
Stack Overflow: https://stackoverflow.com/questions/tagged/pact
Say 👋 on Twitter: @pact_up

Installation #
# install pact_dart as a dev dependency
dart pub add --dev pact_dart

# download and install the required libraries
dart run pact_dart:install

# 🚀 now write some tests!
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Flutter Instructions
Flutter Installation #
# install pact_dart as a dev dependency
flutter pub add --dev pact_dart

# download and install the required libraries
flutter pub run pact_dart:install

# 🚀 now write some tests!
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Manual Installation Instructions
Modify Library Location #
By default, the Pact FFI Library is installed to /usr/local/lib on macOS and Linux. However, you can use the PACT_DART_LIB_DOWNLOAD_PATH environment variable to modify the installation path.
PACT_DART_LIB_DOWNLOAD_PATH=/app/my-other-location dart run pact_dart:install
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Manual Installation #
Download the latest Pact FFI Library [libraries] for your OS, and install onto a standard library search path (for example, we suggest: /usr/local/lib on OSX/Linux):
Ensure you have the correct extension for your OS:

For Mac OSX: .dylib
For Linux: .so
For Windows: .dll

wget https://github.com/pact-foundation/pact-reference/releases/download/libpact_ffi-v0.0.2/libpact_ffi-osx-x86_64.dylib.gz
gunzip libpact_ffi-osx-x86_64.dylib.gz
mv libpact_ffi-osx-x86_64.dylib /usr/local/lib/libpact_ffi.dylib
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Usage #
Writing a Consumer test #
Pact is a consumer-driven contract testing tool, which is a fancy way of saying that the API Consumer writes a test to set out its assumptions and needs of its API Provider(s). By unit testing our API client with Pact, it will produce a contract that we can share to our Provider to confirm these assumptions and prevent breaking changes.
In this example, we are testing the users repository that communicates with the /users resource of a HTTP service. The repository has a single method fetchAll() that will return a list of users.
import 'package:pact_dart/pact_dart.dart';

final pact = PactMockService('FlutterConsumer','APIService');

pact
.newInteraction()
.given('a user exists', params: {'first_name': 'Betsy', 'last_name': 'Tester'})
.andGiven('')
.uponReceiving('a request for all users')
.withRequest('GET', '/users')
.willRespondWith(200, body: {
// Matchers are used here as we care about the types and structure of the response and not the exact values.
'page': PactMatchers.SomethingLike(1),
'per_page': PactMatchers.SomethingLike(20),
'total': PactMatchers.IntegerLike(20),
'total_pages': PactMatchers.SomethingLike(3),
'data': PactMatchers.EachLike([
{
'id': PactMatchers.uuid('f3a9cf4a-92d7-4aae-a945-63a6440b528b'),
'first_name': PactMatchers.SomethingLike('Betsy'),
'last_name': PactMatchers.SomethingLike('Tester'),
'salary': PactMatchers.DecimalLike(125000.00)
}
])
});

pact.run(secure: false);

final loginRepository = UsersRepository();
final users = await loginRepository.fetchAll();

expect(users.count, equals(20));
expect(users[0].first_name, equals('Betsy'));
expect(users[0].last_name, equals('Tester'));

pact.writePactFile();
pact.reset();
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Compatibility #
Feature Compatibility



Feature
Supported




HTTP Pacts
✅


Asychronous message pacts
❌


Regular expression matching
✅


Type based matching ("like")
✅


Flexible array length ("each like")
✅


Verify a pact that uses the Pact specification v3 format
✅


Pact specification v3 matchers
🔨


Pact specification v3 generators
❌


Multiple provider states (pact creation)
✅


Multiple provider states (pact verification)
❌


Publish pacts to Pact Broker
❌


Tag consumer version in Pact Broker when publishing pact
❌


Dynamically fetch pacts for provider from Pact Broker for verification
❌


Dynamically fetch pacts for provider with specified tags
❌


Automatically tag consumer/provider with name of git branch
❌


Use 'pacts for verification' Pact Broker API
❌


Pending pacts
❌


WIP pacts
❌


JSON test results output
❌


XML test results output
❌


Markdown test results output
❌


Run a single interaction when verifying a pact
❌


Injecting values from provider state callbacks
❌


Date/Time expressions with generators
❌




✅ -- Implemented
🔨 -- Partially implemented
❌ -- Not implemented