Merge pull request #10 from Ambro17/add-support-for-args-injection

Add support for args injection in view functions

Author: Ambro17

.flake8

@@ -1,2 +1,4 @@
 [flake8]
+ignore=E302
 max-line-length=119
+max-complexity=10

.pre-commit-config.yaml

@@ -0,0 +1,20 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v3.0.0
+    hooks:
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+      - id: check-added-large-files
+      - id: check-merge-conflict
+      - id: debug-statements
+      - id: end-of-file-fixer
+      - id: requirements-txt-fixer
+
+  - repo: https://gitlab.com/pycqa/flake8
+    rev: 3.8.1
+    hooks:
+      - id: flake8
+        language_version: python3
+        args: ['src/slackify', 'tests']
+    stages:
+      - push

README.md

@@ -1,6 +1,7 @@
 # Slackify
 ![Build & Test](https://github.com/Ambro17/flask-slack/workflows/Build%20&%20Test/badge.svg)
 [![codecov](https://codecov.io/gh/Ambro17/flask-slack/branch/master/graph/badge.svg)](https://codecov.io/gh/Ambro17/flask-slack)
+[![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white)](https://github.com/pre-commit/pre-commit)
 
 `Slackify` is a light framework designed to accelerate your development of slack apps by letting you focus on **what you want** instead of fighting with *how to do it*
 
@@ -78,6 +79,21 @@ Yes! See [examples/actions.py](examples/actions.py) for a quickstart.
 ### And slack events?
 As you may have guessed, they are also supported. See [examples/events.py](examples/events.py) for an example.
 
+## Dependency Injection
+As you add more and more commands you will find yourself repeating yourself while parsing slack request on every function
+
+The lib offers a solution to this with dependency injection.
+```python
+@slackify.command
+def hello(command, command_args, response_url):
+    return reply_text(f"You called `{command} {command_args}`. Use {response_url} for delayed responses")
+```
+Your view function will now get the request command, arguments and response_url for free! Pretty cool, right?
+
+If you are a user of pytest, this idea is similar to pytest fixtures
+
+See [examples/injection.py](examples/injection.py) for the full example
+
 
 ## Full example
 Here you have a more complete example showcasing all functionality. It includes:
@@ -143,20 +159,18 @@ def hello():
 
 
 @slackify.action("yes")
-def yes():
+def yes(payload):
     """If a user clicks yes on the message above, execute this callback"""
-    action = json.loads(request.form["payload"])
     text_blok = text_block('Super! I do too :thumbsup:')
-    respond(action['response_url'], {'blocks': [text_blok]})
+    respond(payload['response_url'], {'blocks': [text_blok]})
     return OK
 
 
 @slackify.action("no")
-def no():
+def no(payload):
     """If a user clicks no on the hello message, execute this callback"""
-    action = json.loads(request.form["payload"])
     text_blok = text_block('Boo! You are so boring :thumbsdown:')
-    respond(action['response_url'], {'blocks': [text_blok]})
+    respond(payload['response_url'], {'blocks': [text_blok]})
     return OK
 
 
@@ -230,12 +244,11 @@ def register():
 
 
 @slackify.view("registration_form")
-def register_callback():
+def register_callback(payload):
     """Handle registration form submission."""
-    action = json.loads(request.form["payload"])
-    response = action['view']['state']['values']
+    response = payload['view']['state']['values']
     text_blok = text_block(f':heavy_check_mark: You are now registered.\nForm payload:\n```{response}```')
-    send_message(cli, [text_blok], action['user']['id'])
+    send_message(cli, [text_blok], payload['user']['id'])
     return ACK
 
 
@@ -245,9 +258,8 @@ def send_message(cli, blocks, user_id):
 
 
 @slackify.shortcut('dice_roll')
-def dice_roll():
+def dice_roll(payload):
     """Roll a virtual dice to give a pseudo-random number"""
-    payload = json.loads(request.form['payload'])
     dice_value = random.randint(1, 6)
     msg = f'🎲 {dice_value}'
     send_message(cli, blocks=[text_block(msg)], user_id=payload['user']['id'])
@@ -273,12 +285,11 @@ def say_hi(payload):
 ```
 
 ## Usage as a Blueprint
-If you already have a Flask app, you can attach 
+If you already have a Flask app, you can attach
 flask functionality _slackifying_ your blueprint
 ```python
 # slack_blueprint.py
-from flask import Blueprint
-from slackify import Slackify, reply_text
+from slackify import Slackify, reply_text, Blueprint
 
 bp = Blueprint('slackify_bp', __name__, url_prefix='/slack')
 slackify = Slackify(app=bp)
@@ -299,6 +310,7 @@ def create_app():
     return app
 
 ```
+> Note: You must import Blueprint from slackify instead of flask to get it working
 
 ## API Reference
 ```python
@@ -333,7 +345,7 @@ or
 @slackify.default
 
 # Handle unexpected errors that occur inside handlers.
-# By default returns status 500 and a generic message. 
+# By default returns status 500 and a generic message.
 # The exception will be passed as a positional argument to the decorated function
 @slackify.error
 ```
@@ -349,11 +361,11 @@ The lib exposes a main class called `Slackify` that can either receive a Flask i
 as `app` argument or creates one on the fly.
 It then binds two routes. One for commands, shortcuts, actions and another one for slack events.
 
-The first route is `/` by default, it inspects the incoming requests and looks for any declared handler that is interested in handling this request to redirect it. 
+The first route is `/` by default, it inspects the incoming requests and looks for any declared handler that is interested in handling this request to redirect it.
 
-If it finds a handler, it redirects the request to that function by overriding its `Request.url_rule.endpoint`
+If it finds a handler, it injects any dependency the view may require as a view argument, and then call the view function, passing the return value as the request response.
 
-If there's no match, it ignores the request and it follows the 
+If there's no match, it ignores the request and it follows the
 normal request lifecycle.
 
 If there's an error, an overridable function through `@slackify.error` is executed to show a friendly message.
@@ -363,9 +375,6 @@ The second route the lib adds is the events route at `/slack/events`.
 When it receives a post request, it emits an event through `pyee.ExecutorEventEmitter` with the event type and quickly responds with the response acknowledgment slack requires to avoid showing an error to the user. This allows asynchronous execution of the function, while still responding quickly to slack.
 In other words, when you decorate a function with `app.event('event_type')` what you are really doing is setting up a listener for the `event_type` that will receive the event payload. No magic.
 
-If after reading this you have an idea of how we can extend or improve this lib in any way, i would be really grateful to receive an issue or pull request!
+If after reading this you have an idea of how we can extend or improve this lib in any way, it would be great to receive an issue or pull request!
 I feel there's still a void on slack bots with python that java and javascript have covered with [bolt's](https://github.com/slackapi/bolt) beautiful API.
 Below you can find the current roadmap of features i would like to include.
-
-## Roadmap
-1. Inject payload argument to slack event handlers to avoid code repetition on loading request data.

app.json

@@ -15,4 +15,4 @@
         "value": ""
     }
   }
-}
+}

examples/as_blueprint.py

@@ -1,6 +1,5 @@
 # slack_blueprint.py
-from flask import Blueprint
-from slackify import Slackify, reply_text
+from slackify import Slackify, Blueprint, reply_text
 
 bp = Blueprint('slackify_bp', __name__, url_prefix='/slack')
 slackify = Slackify(app=bp)
@@ -12,7 +11,7 @@ def hello():
 
 
 # app.py
-from flask import Flask
+from flask import Flask                                 # noqa: Ignore E402, as it is an example
 # from slack_blueprint import bp
 
 def create_app():

examples/commands.py

@@ -15,4 +15,4 @@ def hello():
 
 @slackify.command(name='bye')
 def goodbye():
-    return reply_text(f'Goodbye')
+    return reply_text('Goodbye')

examples/full.py

@@ -1,4 +1,3 @@
-import json
 import os
 import random
 
@@ -51,16 +50,14 @@ def hello():
 
 
 @slackify.action("yes")
-def yes():
-    action = json.loads(request.form["payload"])
+def yes(action):
     text_blok = text_block('Super! I do too :thumbsup:')
     respond(action['response_url'], {'blocks': [text_blok]})
     return OK
 
 
 @slackify.action("no")
-def no():
-    action = json.loads(request.form["payload"])
+def no(action):
     text_blok = text_block('Boo! You are so boring :thumbsdown:')
     respond(action['response_url'], {'blocks': [text_blok]})
     return OK
@@ -135,11 +132,10 @@ def register():
 
 
 @slackify.view("registration_form")
-def register_callback():
-    action = json.loads(request.form["payload"])
-    response = action['view']['state']['values']
+def register_callback(payload):
+    response = payload['view']['state']['values']
     text_blok = text_block(f':heavy_check_mark: You are now registered.\nForm payload:\n```{response}```')
-    send_message(cli, [text_blok], action['user']['id'])
+    send_message(cli, [text_blok], payload['user']['id'])
     return ACK
 
 
@@ -149,8 +145,7 @@ def send_message(cli, blocks, user_id):
 
 
 @slackify.shortcut('dice_roll')
-def dice_roll():
-    payload = json.loads(request.form['payload'])
+def dice_roll(payload):
     dice_value = random.randint(1, 6)
     msg = f'🎲 {dice_value}'
     send_message(cli, blocks=[text_block(msg)], user_id=payload['user']['id'])

examples/injection.py

@@ -0,0 +1,16 @@
+from flask import Flask
+from slackify import Slackify, reply_text, Slack, ACK
+
+app = Flask(__name__)
+slackify = Slackify(app=app)
+cli = Slack('xoxb-SECRET')
+
+@slackify.command
+def hello(command, command_args, response_url):
+    return reply_text(f"You called `{command} {command_args}`. POST to {response_url} for delayed responses (>3sec)")
+
+
+@slackify.shortcut('greet_me')
+def goodbye(payload):
+    cli.chat_postMessage(channel='#general', text=f'Knock Knock\n`{payload}`')
+    return ACK

examples/shortcuts.py

@@ -14,5 +14,5 @@ def tell_joke():
     payload = json.loads(request.form['payload'])
     user = payload['user']
     name = user.get('username', user.get('id'))
-    cli.chat_postMessage('#general', text=f'Knock Knock `{name}`')
+    cli.chat_postMessage(channel='#general', text=f'Knock Knock `{name}`')
     return '', 200

examples/views.py

@@ -2,6 +2,8 @@
 from slackify import Slackify, request, text_block, Slack, ACK
 import json
 
+from slackify.tasks import async_task
+
 
 # Important! Before running set FLASK_APP=examples.async_task:app
 app = Flask(__name__)
@@ -97,5 +99,6 @@ def register_callback():
     return ACK
 
 
+@async_task
 def send_message(cli, blocks, user_id):
     return cli.chat_postMessage(channel=user_id, user_id=user_id, blocks=blocks)