feat: Message Provider Implementation

examples/message/README.md

@@ -41,7 +41,7 @@ class MessageHandler(object):
 ```
 
 Below is a snippet from a test where the message handler has no error.
-Since the expected event contains a key `documentType` with value `microsoft-word`, message handler does not throw an error and a pact file `f"pacts/{expected_json}"` is expected to be generated.
+Since the expected event contains a key `documentType` with value `microsoft-word`, message handler does not throw an error and a pact file `f"{PACT_FILE}""` is expected to be generated.
 
 ```python
 def test_generate_new_pact_file(pact):
@@ -69,7 +69,7 @@ def test_generate_new_pact_file(pact):
     assert isfile(f"{PACT_FILE}") == 1
 ```
 
-For a similar test where the event does not contain a key `documentType` with value `microsoft-word`, a `CustomError` is generated and there there is no generated json file `f"pacts/{expected_json}"`.
+For a similar test where the event does not contain a key `documentType` with value `microsoft-word`, a `CustomError` is generated and there there is no generated json file `f"{PACT_FILE}"`.
 
 ```python
 def test_throw_exception_handler(pact):
@@ -97,8 +97,6 @@ def test_throw_exception_handler(pact):
     assert isfile(f"{PACT_FILE}") == 0
 ```
 
-Otherwise, no pact file is generated.
-
 ## Provider
 
 Note: The current example only tests the consumer side.

examples/message/src/message_handler.py

@@ -15,5 +15,5 @@ def __init__(self, event):
 
     @staticmethod
     def pass_event(event):
-        if event.get('documentType') != 'microsoft-word':
+        if event.get('documentType') != 'application/pdf':
             raise CustomError("Not correct document type")

examples/message/tests/consumer/test_message_consumer.py

@@ -19,7 +19,7 @@
 PACT_DIR = 'pacts'
 
 CONSUMER_NAME = 'DetectContentLambda'
-PROVIDER_NAME = 'ContentProvider'
+PROVIDER_NAME = 'DocumentService'
 PACT_FILE = (f"{CONSUMER_NAME.lower().replace(' ', '_')}_message-"
              + f"{PROVIDER_NAME.lower().replace(' ', '_')}_message.json")
 
@@ -65,14 +65,13 @@ def progressive_delay(file, time_to_wait=10, second_interval=0.5, verbose=False)
 def test_throw_exception_handler(pact):
     cleanup_json(PACT_FILE)
     wrong_event = {
-        'documentName': 'spreadsheet.xls',
-        'creator': 'WI',
-        'documentType': 'microsoft-excel'
+        "event": "ObjectCreated:Put",
+        "documentType": "application/jpg"
     }
 
     (pact
-     .given('Another document in Document Service')
-     .expects_to_receive('Description')
+     .given('Does not matter')
+     .expects_to_receive('it wont make it to the pact file')
      .with_content(wrong_event)
      .with_metadata({
          'Content-Type': 'application/json'
@@ -87,25 +86,25 @@ def test_throw_exception_handler(pact):
     assert isfile(f"{PACT_FILE}") == 0
 
 
-def test_generate_new_pact_file(pact):
+def test_a_document_created_successfully(pact):
     cleanup_json(PACT_FILE)
 
     expected_event = {
-        'documentName': 'document.doc',
-        'creator': 'TP',
-        'documentType': 'microsoft-word'
+        "event": "ObjectCreated:Put",
+        "bucket": "bucket_name",
+        "key": "path_to_file_in_s3.pdf",
+        "documentType": "application/pdf"
     }
 
     (pact
-     .given('A document create in Document Service')
-     .expects_to_receive('Description')
+     .given('A document created successfully')
+     .expects_to_receive('Document created in Document Service')
      .with_content(expected_event)
      .with_metadata({
          'Content-Type': 'application/json'
      }))
 
     with pact:
-        # handler needs 'documentType' == 'microsoft-word'
         MessageHandler(expected_event)
 
     progressive_delay(f"{PACT_FILE}")
@@ -122,14 +121,15 @@ def test_publish_to_broker(pact):
     `pytest tests/consumer/test_message_consumer.py::test_publish_pact_to_broker --publish-pact 2`
     """
     expected_event = {
-        'documentName': 'document.doc',
-        'creator': 'TP',
-        'documentType': 'microsoft-word'
+        "event": "ObjectCreated:Delete",
+        "bucket": "bucket_name",
+        "key": "existing_file_in_s3.pdf",
+        "documentType": "application/pdf"
     }
 
     (pact
-     .given('A document create in Document Service with broker')
-     .expects_to_receive('Description with broker')
+     .given('A document deleted successfully')
+     .expects_to_receive('Document deleted in Document Service')
      .with_content(expected_event)
      .with_metadata({
          'Content-Type': 'application/json'

examples/message/tests/provider/test_message_provider.py

@@ -0,0 +1,43 @@
+import pytest
+from pact import MessageProvider
+
+def document_created_handler():
+    return {
+        "event": "ObjectCreated:Put",
+        "bucket": "bucket_name",
+        "key": "path_to_file_in_s3.pdf",
+        "documentType": "application/pdf"
+    }
+
+def document_deleted_handler():
+    return {
+        "event": "ObjectCreated:Delete",
+        "bucket": "bucket_name",
+        "key": "existing_file_in_s3.pdf",
+        "documentType": "application/pdf"
+    }
+
+def test_verify_success():
+    provider = MessageProvider(
+        message_providers={
+            'A document created successfully': document_created_handler,
+            'A document deleted successfully': document_deleted_handler
+        },
+        provider='DocumentService',
+        consumer='DetectContentLambda'
+    )
+    with provider:
+        provider.verify()
+
+def test_verify_failure_when_a_provider_missing():
+    provider = MessageProvider(
+        message_providers={
+            'A document created successfully': document_created_handler,
+        },
+        provider='DocumentService',
+        consumer='DetectContentLambda'
+    )
+
+    with pytest.raises(AssertionError):
+        with provider:
+            provider.verify()

pact/__init__.py

@@ -2,13 +2,15 @@
 from .broker import Broker
 from .consumer import Consumer
 from .matchers import EachLike, Like, SomethingLike, Term, Format
-from .message_pact import MessagePact
 from .message_consumer import MessageConsumer
+from .message_pact import MessagePact
+from .message_provider import MessageProvider
 from .pact import Pact
 from .provider import Provider
 from .verifier import Verifier
 
 from .__version__ import __version__  # noqa: F401
 
-__all__ = ('Broker', 'Consumer', 'EachLike', 'Like', 'MessageConsumer', 'MessagePact',
+__all__ = ('Broker', 'Consumer', 'EachLike', 'Like',
+           'MessageConsumer', 'MessagePact', 'MessageProvider',
            'Pact', 'Provider', 'SomethingLike', 'Term', 'Format', 'Verifier')

pact/broker.py

@@ -84,7 +84,7 @@ def publish(self, consumer_name, version, pact_dir=None,
             for tag in consumer_tags:
                 command.extend(['-t', tag])
 
-        print(f"PactBroker command: {command}")
+        log.debug(f"PactBroker publish command: {command}")
 
         publish_process = Popen(command)
         publish_process.wait()

pact/http_proxy.py

@@ -0,0 +1,103 @@
+"""Http Proxy to be used as provider url in verifier."""
+from werkzeug.local import LocalStack
+from flask import Flask, jsonify, request
+from werkzeug.exceptions import HTTPException
+import json
+import logging
+log = logging.getLogger(__name__)
+logging.basicConfig(level=logging.DEBUG)
+
+app = Flask(__name__)
+localstack = LocalStack()
+PROXY_PORT = 1234
+
+def shutdown_server():
+    """Shutdown Http Proxy server."""
+    shutdown = request.environ.get('werkzeug.server.shutdown')
+    if shutdown is None:
+        raise RuntimeError('Not running with the Werkzeug Server')
+    shutdown()
+
+def _match_states(payload):
+    """Match states in payload against stored message handlers."""
+    log.debug(f'Find handler from payload: {payload}')
+    handlers = localstack.top
+    states = handlers['messageHandlers']
+    log.debug(f'Setup states: {handlers}')
+    provider_states = payload['providerStates']
+
+    for state in provider_states:
+        matching_state = state['name']
+        if matching_state in states:
+            return states[matching_state]
+    raise RuntimeError('No matched handler.')
+
+@app.route('/', methods=['POST'])
+def home():
+    """Match states with provided message handlers."""
+    payload = request.json
+    message = _match_states(payload)
+    res = jsonify({
+        'contents': message
+    })
+    res.status_code = 200
+    return res
+
+@app.route('/ping', methods=['GET'])
+def ping():
+    """Check whether the server is available before setting up states."""
+    res = jsonify({
+        'ping': 'pong'
+    })
+    res.status_code = 200
+    return res
+
+@app.route("/setup", methods=['POST'])
+def setup():
+    """Endpoint to setup states.
+
+    Use localstack to store payload.
+    """
+    payload = request.json
+    # Store payload in localstack
+    localstack.push(payload)
+    res = jsonify(payload)
+    res.status_code = 201
+    return res
+
+@app.route('/shutdown', methods=['POST'])
+def shutdown():
+    """Shutdown Http Proxy server."""
+    shutdown_server()
+    return 'Server shutting down...'
+
+@app.errorhandler(HTTPException)
+def handle_exception(e):
+    """Return JSON instead of HTML for HTTP errors."""
+    res = e.get_response()
+    res.data = json.dumps({
+        "code": e.code,
+        "name": e.name,
+        "description": e.description,
+    })
+    res.content_type = "application/json"
+    return res
+
+@app.errorhandler(RuntimeError)
+def handle_runtime_error(e):
+    """Handle the RuntimeError.
+
+    Handle HTML stacktrace when RuntimeError occurs due to no matched handler.
+    when the verifier fails.
+    """
+    res = jsonify({
+        "name": "RuntimeError",
+        "description": str(e),
+    })
+    res.status_code = 500
+    res.content_type = "application/json"
+    return res
+
+
+if __name__ == '__main__':
+    app.run(debug=True, port=PROXY_PORT)

pact/message_pact.py

@@ -7,7 +7,7 @@
 
 from .broker import Broker
 from .constants import MESSAGE_PATH
-
+from .matchers import from_term
 
 class MessagePact(Broker):
     """
@@ -136,7 +136,7 @@ def with_content(self, contents):
         :rtype: Pact
         """
         self._insert_message_if_complete()
-        self._messages[0]['contents'] = contents
+        self._messages[0]['contents'] = from_term(contents)
         return self
 
     def expects_to_receive(self, description):