ergonomic linear web hook registration (#484)

# Motivation

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# Content

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# Testing

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# Please check the following before marking your PR as ready for review

- [ ] I have added tests for my changes
- [ ] I have updated the documentation or added new documentation as
needed

Author: rushilpatel0

src/codegen/extensions/clients/linear.py

@@ -0,0 +1,162 @@
+import json
+import logging
+
+import requests
+from pydantic import BaseModel
+
+logger = logging.getLogger(__name__)
+
+
+# --- TYPES
+
+
+class LinearUser(BaseModel):
+    id: str
+    name: str
+
+
+class LinearComment(BaseModel):
+    id: str
+    body: str
+    user: LinearUser | None = None
+
+
+class LinearIssue(BaseModel):
+    id: str
+    title: str
+    description: str | None = None
+
+
+class LinearClient:
+    api_headers: dict
+    api_endpoint = "https://api.linear.app/graphql"
+
+    def __init__(self, access_token: str):
+        self.access_token = access_token
+        self.api_headers = {
+            "Content-Type": "application/json",
+            "Authorization": self.access_token,
+        }
+
+    def get_issue(self, issue_id: str) -> LinearIssue:
+        query = """
+            query getIssue($issueId: String!) {
+                issue(id: $issueId) {
+                    id
+                    title
+                    description
+                }
+            }
+        """
+        variables = {"issueId": issue_id}
+        response = requests.post(self.api_endpoint, headers=self.api_headers, json={"query": query, "variables": variables})
+        data = response.json()
+        issue_data = data["data"]["issue"]
+        return LinearIssue(id=issue_data["id"], title=issue_data["title"], description=issue_data["description"])
+
+    def get_issue_comments(self, issue_id: str) -> list[LinearComment]:
+        query = """
+            query getIssueComments($issueId: String!) {
+                issue(id: $issueId) {
+                    comments {
+                    nodes {
+                        id
+                        body
+                        user {
+                            id
+                            name
+                        }
+                    }
+
+                    }
+                }
+            }
+        """
+        variables = {"issueId": issue_id}
+        response = requests.post(self.api_endpoint, headers=self.api_headers, json={"query": query, "variables": variables})
+        data = response.json()
+        comments = data["data"]["issue"]["comments"]["nodes"]
+
+        # Parse comments into list of LinearComment objects
+        parsed_comments = []
+        for comment in comments:
+            user = comment.get("user", None)
+            parsed_comment = LinearComment(id=comment["id"], body=comment["body"], user=LinearUser(id=user.get("id"), name=user.get("name")) if user else None)
+            parsed_comments.append(parsed_comment)
+
+        # Convert raw comments to LinearComment objects
+        return parsed_comments
+
+    def comment_on_issue(self, issue_id: str, body: str) -> dict:
+        """issue_id is our internal issue ID"""
+        query = """mutation makeComment($issueId: String!, $body: String!) {
+          commentCreate(input: {issueId: $issueId, body: $body}) {
+            comment {
+              id
+              body
+              url
+              user {
+                id
+                name
+              }
+            }
+          }
+        }
+        """
+        variables = {"issueId": issue_id, "body": body}
+        response = requests.post(
+            self.api_endpoint,
+            headers=self.api_headers,
+            data=json.dumps({"query": query, "variables": variables}),
+        )
+        data = response.json()
+        try:
+            comment_data = data["data"]["commentCreate"]["comment"]
+
+            return comment_data
+        except:
+            msg = f"Error creating comment\n{data}"
+            raise Exception(msg)
+
+    def unregister_webhook(self, webhook_id: str):
+        mutation = """
+            mutation deleteWebhook($id: String!) {
+                webhookDelete(id: $id) {
+                    success
+                }
+            }
+        """
+        variables = {"id": webhook_id}
+        response = requests.post(self.api_endpoint, headers=self.api_headers, json={"query": mutation, "variables": variables})
+        return response.json()
+
+    def register_webhook(self, webhook_url: str, team_id: str, secret: str, enabled: bool, resource_types: list[str]):
+        mutation = """
+            mutation createWebhook($input: WebhookCreateInput!) {
+                webhookCreate(input: $input) {
+                    success
+                    webhook {
+                        id
+                        enabled
+                    }
+                }
+            }
+        """
+
+        variables = {
+            "input": {
+                "url": webhook_url,
+                "teamId": team_id,
+                "resourceTypes": resource_types,
+                "enabled": enabled,
+                "secret": secret,
+            }
+        }
+
+        response = requests.post(self.api_endpoint, headers=self.api_headers, json={"query": mutation, "variables": variables})
+        if response.status_code != 200:
+            return None
+
+        body = response.json()
+        body = body["data"]["webhookCreate"]["webhook"]["id"]
+        return body

src/codegen/extensions/events/app.py

@@ -0,0 +1,21 @@
+import logging
+
+import modal
+
+from codegen.extensions.events.linear import Linear
+
+logger = logging.getLogger(__name__)
+
+
+class CodegenApp(modal.App):
+    linear: Linear
+
+    def __init__(self, name, modal_api_key, image: modal.Image):
+        self._modal_api_key = modal_api_key
+        self._image = image
+        self._name = name
+
+        super().__init__(name=name, image=image)
+
+        # Expose a attribute that provides the event decorator for different providers.
+        self.linear = Linear(self)

src/codegen/extensions/events/interface.py

@@ -0,0 +1,14 @@
+from typing import Protocol
+
+import modal
+
+
+class EventHandlerManagerProtocol(Protocol):
+    def subscribe_handler_to_webhook(self, func_name: str, modal_app: modal.App, event_name):
+        pass
+
+    def unsubscribe_handler_to_webhook(self, func_name: str, modal_app: modal.App, event_name):
+        pass
+
+    def unsubscribe_all_handlers(self):
+        pass

src/codegen/extensions/events/linear.py

@@ -0,0 +1,76 @@
+import functools
+import logging
+import os
+from typing import Callable
+
+import modal
+from anthropic import BaseModel
+
+from codegen.extensions.clients.linear import LinearClient
+from codegen.extensions.events.interface import EventHandlerManagerProtocol
+
+logger = logging.getLogger(__name__)
+
+
+class RegisteredWebhookHandler(BaseModel):
+    webhook_id: str | None = None
+    handler_func: Callable
+
+
+class Linear(EventHandlerManagerProtocol):
+    def __init__(self, app: modal.App):
+        self.app = app
+        self.access_token = os.environ["LINEAR_ACCESS_TOKEN"]  # move to extensions config.
+        self.signing_secret = os.environ["LINEAR_SIGNING_SECRET"]
+        self.linear_team_id = os.environ["LINEAR_TEAM_ID"]
+        self.registered_handlers = {}
+
+    def subscribe_handler_to_webhook(self, web_url: str, event_name: str):
+        client = LinearClient(access_token=self.access_token)
+
+        result = client.register_webhook(team_id=self.linear_team_id, webhook_url=web_url, enabled=True, resource_types=[event_name], secret=self.signing_secret)
+        return result
+
+    def unsubscribe_handler_to_webhook(self, registered_handler: RegisteredWebhookHandler):
+        webhook_id = registered_handler.webhook_id
+
+        client = LinearClient(access_token=self.access_token)
+        if webhook_id:
+            print(f"Unsubscribing from webhook {webhook_id}")
+            result = client.unregister_webhook(webhook_id)
+            return result
+        else:
+            print("No webhook id found for handler")
+            return None
+
+    def unsubscribe_all_handlers(self):
+        for handler in self.registered_handlers:
+            self.unsubscribe_handler_to_webhook(self.registered_handlers[handler])
+
+    def event(self, event_name):
+        """Decorator for registering an event handler.
+
+        :param event_name: The name of the event to handle.
+        :param register_hook: An optional function to call during registration,
+                              e.g., to make an API call to register the webhook.
+        """
+
+        def decorator(func):
+            # Register the handler with the app's registry.
+            modal_ready_func = func
+            func_name = func.__qualname__
+            app_name = self.app.name
+            web_url = modal.Function.from_name(app_name=app_name, name=func_name).web_url
+
+            self.registered_handlers[func_name] = RegisteredWebhookHandler(handler_func=modal_ready_func)
+
+            webhook_id = self.subscribe_handler_to_webhook(web_url=web_url, event_name=event_name)
+            self.registered_handlers[func_name].webhook_id = webhook_id
+
+            @functools.wraps(func)
+            def wrapper(*args, **kwargs):
+                return func(*args, **kwargs)
+
+            return wrapper
+
+        return decorator