build: add changed pact workflow

.github/workflows/verify_changed_contract.yml

@@ -0,0 +1,43 @@
+name: Verify contract changed by a consumer
+
+on:
+  repository_dispatch:
+    types:
+      - contract_changed
+
+env:
+  CHANGED_PACT_URL: ${{ github.event.client_payload.pact_url }}
+  GIT_ENV: Production
+  PACT_BROKER_BASE_URL: https://edx.pactflow.io
+  PACT_BROKER_TOKEN: ${{ secrets.PACT_FLOW_ACCESS_TOKEN }}
+  PUBLISH_VERIFICATION_RESULTS: true
+  VERIFY_WITH_BROKER: false
+
+jobs:
+  changed-contract-verification:
+    name: Pact Provider Verification for a changed contract
+    runs-on: ubuntu-20.04
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v2
+
+    - name: setup python
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3.8
+
+    - name: Install pip
+      run: pip install -r requirements/pip.txt
+
+    - name: Install Dependencies
+      run: |
+        pip install -r requirements/ci.txt
+        pip install -r requirements/test.txt
+
+    - name: Verify Changed Contract
+      run: |
+        export PUBLISH_VERSION=`git rev-parse --short HEAD`
+        export PUBLISH_TAGS=${GITHUB_REF:11}
+        export GIT_ENV='production'
+        pytest -s edxval/pacts/verify_pact.py --ds=edxval.settings.pact

edxval/pacts/README.md

@@ -5,7 +5,9 @@ This readme contains the description of different files in the current directory
 * views.py: This will have provider state setup view which is hit during provider verification to setup appropriate DB state per interaction
 * utils.py: Different DB utilities used by views.py
 * video-encode-manager-edx-val.json: The only pact file is a duplicate of pact file from https://github.com/edx/video-encode-manager/blob/a4f4c12db0c3919858df1e2fa58ee74071bc264a/encode_manager/apps/core/tests/pact_tests/pacts/video-encode-manager-edx-val.json. This is temporarily needed until pact broker can be setup. Until then, any update in the original pact should be ported in the json in VAL.
-* verify_pact.py: Runs the provider verification against the pact(either JSON file in the current directory or via pact broker). To run the verification, either of the following two commands can be used
-  * `DJANGO_SETTINGS_MODULE=edxval.settings.pact pytest -s edxval/pacts/verify_pact.py` 
-  * `pytest -s edxval/pacts/verify_pact.py --ds=edxval.settings.pact`
+* verify_pact.py: Runs the provider verification against the pact. Use either `DJANGO_SETTINGS_MODULE=edxval.settings.pact pytest -s edxval/pacts/verify_pact.py` or `pytest -s edxval/pacts/verify_pact.py --ds=edxval.settings.pact` commands to run the verification.
+ There are 3 instances of running the verification:
+  * **Verify with broker**: By default, the verification is done against the broker.
+  * **Changed Pact's Verification**: For this verification, `VERIFY_WITH_BROKER` environment variable should be set to False and `CHANGED_PACT_URL` should point to a valid pact.
+  * **Local JSON Pact**: Similar to Changed Pact Verification. Alternatively, if only `VERIFY_WITH_BROKER` is set to False, the pact named video-encode-manager-edx-val.json will be verified.
 

edxval/pacts/verify_pact.py

@@ -17,16 +17,23 @@
 class ProviderVerificationServer(LiveServerTestCase):
     """ Execute the provider verification on the consumer pacts """
 
-    PACT_CONFIG = {
+    PACT_DEFAULT_CONFIG = {
+        'enable_pending': True,
+        'headers': ['Pact-Authentication: AllowAny', ],
+        'verbose': False,
+        'publish_version': settings.PUBLISH_VERSION,
+        'provider_tags': [settings.PUBLISH_TAGS, settings.GIT_ENV],
+        'publish_verification_results': settings.PUBLISH_VERIFICATION_RESULTS,
+        'verify_with_broker': settings.VERIFY_WITH_BROKER,
+    }
+
+    PACT_BROKER_CONFIG = {
         'broker_url': settings.PACT_BROKER_BASE_URL,
         'consumer_version_selectors': [
             {'tag': 'production', 'latest': True},
             {"tag": "master", "latest": True},
         ],
-        'publish_version': settings.PUBLISH_VERSION,
-        'provider_tags': [settings.PUBLISH_TAGS, settings.GIT_ENV],
-        'publish_verification_results': settings.PUBLISH_VERIFICATION_RESULTS,
-        'headers': ['Pact-Authentication: AllowAny', ],
+        **PACT_DEFAULT_CONFIG
     }
 
     @classmethod
@@ -45,19 +52,23 @@ def tearDownClass(cls):
     def test_verify_pact(self):
         """
         Run provider verification either using pact broker or local pact.
+
+          * If VERIFY_WITH_BROKER environment variable is set, broker config will be used to run verification
+          of pacts on broker.
+          * If VERIFY_WITH_BROKER is not set, the pact specified by CHANGED_PACT_URL environment variable or the
+          local directory pact will be verified. VERIFY_WITH_BROKER is not set when the contract is changed by the
+          consumer and a provider verification build specific to the changed contract should be executed.
         """
-        if self.PACT_CONFIG['publish_verification_results']:
+        if self.PACT_DEFAULT_CONFIG['verify_with_broker']:
             output, _ = self.verifier.verify_with_broker(
-                **self.PACT_CONFIG,
-                verbose=False,
-                enable_pending=True,
+                **self.PACT_BROKER_CONFIG,
                 provider_states_setup_url=f"{self.live_server_url}{reverse('provider-state-view')}",
             )
         else:
             output, _ = self.verifier.verify_pacts(
-                os.path.join(PACT_DIR, PACT_FILE),
+                settings.CHANGED_PACT_URL or os.path.join(PACT_DIR, PACT_FILE),
                 provider_states_setup_url=f"{self.live_server_url}{reverse('provider-state-view')}",
-                headers=self.PACT_CONFIG['headers'],
+                **self.PACT_DEFAULT_CONFIG,
             )
 
         assert output == 0

edxval/settings/pact.py

@@ -8,11 +8,16 @@
 
 from edxval.settings.test import *  # pylint: disable=wildcard-import
 
-PUBLISH_VERIFICATION_RESULTS = os.environ.get('PUBLISH_VERIFICATION_RESULTS', 'False').lower() in ('true', 'yes', '1')
+CHANGED_PACT_URL = os.environ.get('CHANGED_PACT_URL')
+GIT_ENV = os.environ.get('GIT_ENV', 'development')
 PROVIDER_STATES_SETUP_VIEW_URL = True
 PACT_BROKER_BASE_URL = os.environ.get('PACT_BROKER_BASE_URL', 'http://localhost:9292')
-PUBLISH_VERSION = os.environ.get('PUBLISH_VERSION', '1')
 PUBLISH_TAGS = os.environ.get('PUBLISH_TAGS', 'master')
-GIT_ENV = os.environ.get('GIT_ENV')
+PUBLISH_VERSION = os.environ.get('PUBLISH_VERSION', '1')
+PUBLISH_VERIFICATION_RESULTS = os.environ.get('PUBLISH_VERIFICATION_RESULTS', 'False').lower() in ('true', 'yes', '1')
+
+# By default, the verification will be done from broker. This option will need to be
+# overridden when doing verification for a changed contract
+VERIFY_WITH_BROKER = os.environ.get('VERIFY_WITH_BROKER', 'True').lower() in ('true', 'yes', '1')
 
 MIDDLEWARE = MIDDLEWARE + ('edxval.pacts.middleware.AuthenticationMiddleware',)