📝 Document webhooks

docs/hub/_toctree.yml

@@ -12,6 +12,8 @@
     title: Pull Requests & Discussions
   - local: notifications
     title: Notifications
+  - local: webhooks
+    title: Webhooks
   - local: repositories-next-steps
     title: Next Steps
   - local: repositories-licenses

docs/hub/webhooks.md

@@ -0,0 +1,193 @@
+# Webhooks
+
+Webhooks are a foundation for MLOps related features. You can use this to auto-convert models, build community bots, or build CI/CD for your models, datasets, and Spaces.
+
+They allow you to react when new changes happen on specific repos or repos belonging to specific users / organizations (not just your repos, but any repo!).
+
+You can configure the webhooks in your [settings](https://huggingface.co/settings/webhooks):
+
+![Settings of an individual webhook](https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/hub/webhook-settings.png)
+
+You can watch repo changes, discussions, and Pull requests and comments. You can even use a Space to react to webhooks!
+
+<!-- Todo: add a link to a guide with a real example -->
+
+## Webhook Payloads
+
+After registering a webhook, you will be notified of events via an `HTTP POST` call on the specified URL. The payload is encoded in JSON.
+
+You can check the last payloads sent in the activity tab of the webhook page, as well as replay webhooks:
+
+
+![image.png](https://s3.amazonaws.com/moonup/production/uploads/1671034300077-61d2f90c3c2083e1c08af22d.png)
+
+As an example, here is the full payload when a Pull request is opened:
+
+```json
+{
+  "event": {
+    "action": "create",
+    "scope": "discussion"
+  },
+  "repo": {
+    "type": "model",
+    "name": "gpt2",
+    "id": "621ffdc036468d709f17434d",
+    "private": false,
+    "url": {
+      "web": "https://hugginface.co/gpt2",
+      "api": "https://hugginface.co/api/models/gpt2"
+    },
+    "owner": {
+      "id": "628b753283ef59b5be89e937"
+    }
+  },
+  "discussion": {
+    "id": "6399f58518721fdd27fc9ca9",
+    "title": "Update co2 emissions",
+    "url": {
+      "web": "https://hugginface.co/gpt2/discussions/19",
+      "api": "https://hugginface.co/api/models/gpt2/discussions/19"
+    },
+    "status": "open",
+    "author": {
+      "id": "61d2f90c3c2083e1c08af22d"
+    },
+    "num": 19,
+    "isPullRequest": true,
+    "changes": {
+      "base": "refs/heads/main"
+    }
+  },
+  "comment": {
+    "id": "6399f58518721fdd27fc9caa",
+    "author": {
+      "id": "61d2f90c3c2083e1c08af22d"
+    },
+    "content": "Add co2 emissions information to the model card",
+    "hidden": false,
+    "url": {
+      "web": "https://hugginface.co/gpt2/discussions/19#6399f58518721fdd27fc9caa"
+    }
+  },
+  "webhook": {
+    "id": "6390e855e30d9209411de93b",
+    "version": 3
+  }
+}
+```
+
+### Event
+
+The top-level properties `event` is always specified and used to determine the nature of the event.
+
+It has two sub-properties: `event.action` and `event.scope`.
+
+`event.scope` can take one of the following values:
+
+- `"repo"` - Global events on repos. Possible values for the associated `action`: `"create"`, `"delete"`, `"update"`, `"move"`.
+- `"repo.content"` - Events on the repo's content, such as new commits or tags. It triggers on new Pull requests as well due to the newly created reference/commit. The associated `action` is always `"update"`.
+- `"repo.config"` - Events on the config: update Space secrets, update settings, update DOIs, disabled or not, etc. The associated `action` is always `"update"`.
+- `"discussion"` - Creating a discussion or Pull request, updating the title or status, and merging.  Possible values for the associated `action`: `"create"`, `"delete"`, `"update"`.
+- `"discussion.comment"` - Creating, updating, and hiding a comment. Possible values for the associated `action`: `"create"`, `"update"`.
+
+More scopes can be added in the future. To handle unknown events, your webhook handler can consider any action on a narrowed scope to be an `"update"` action on the broader scope.
+
+For example, if the `"repo.config.dois"` scope is added in the future, any event with that scope can be considered by your webhook handler as an `"update"` action on the `"repo.config"` scope.
+
+### Repo
+
+In the current version of webhooks, the top level property `repo` is always specified, as events can always be associated to a repo. For example, consider the following value:
+
+```json
+"repo": {
+	"type": "model",
+	"name": "some-user/some-repo",
+	"id": "6366c000a2abcdf2fd69a080",
+	"private": false,
+	"url": {
+		"web": "http://huggingface.co/some-user/some-repo",
+		"api": "http://huggingface.co/api/models/some-user/some-repo"
+	},
+	"headSha": "c379e821c9c95d613899e8c4343e4bfee2b0c600",
+	"tags": [
+		"license:other",
+		"has_space"
+	],
+	"owner": {
+		"id": "61d2000c3c2083e1c08af22d"
+	}
+}
+```
+
+`repo.headSha` is the sha of the latest commit on the repo's `main` branch. It is only sent when `event.scope` starts with `"repo"`, not on community events like discussions and comments.
+
+### Discussion and Pull Requests
+
+The top level property `discussion` is specified on community events (discussions and Pull requests). The `discussion.isPullRequest` property is a boolean indicating if the discussion is also a Pull request (on the Hub, a PR is a special case of a discussion). Here is an example value:
+
+```json
+"discussion": {
+	"id": "639885d811ae2bad2b7ba461",
+	"title": "Hello!",
+	"url": {
+		"web": "https://huggingface.co/some-user/some-repo/discussions/3",
+		"api": "https://huggingface.co/api/models/some-user/some-repo/discussions/3"
+	},
+	"status": "open",
+	"author": {
+		"id": "61d2000c3c2083e1c08af22d"
+	},
+	"isPullRequest": true,
+	"changes": {
+		"base": "refs/heads/main"
+	}
+	"num": 3
+}
+```
+
+### Comment
+
+The top level property `comment` is specified when a comment is created (including on discussion creation) or updated. Here is an example value:
+
+```json
+"comment": {
+	"id": "6398872887bfcfb93a306f18",
+	"author": {
+		"id": "61d2000c3c2083e1c08af22d"
+	},
+	"content": "This adds an env key",
+	"hidden": false,
+	"url": {
+		"web": "http://huggingface.co/some-user/some-repo/discussions/4#6398872887bfcfb93a306f18"
+	}
+}
+```
+
+## Webhook secret
+
+Setting a webhook secret is useful to make sure payloads sent to your webhook handler come from Hugging Face.
+
+If you set a secret for your webhook, it will be sent along as an `X-Webhook-Secret` HTTP header on every request. Only ASCII characters are supported.
+
+<Tip>
+You can also change the URL of the webhook to add a secret to the URL. For example, setting it to https://example.com/webhook?secret=XXX.
+
+This can be helpful if accessing the HTTP headers of the request is complicated for your webhook handler.
+</Tip>
+
+## Rate limiting
+
+Each webhook is limited to 1,000 triggers per 24 hours. You can check the  daily triggers for your webhook in your webhook settings, in the "Activity" tab.
+
+If you need to increase the number of triggers for your webhook, contact us at [email protected].
+
+## Debugging webhooks
+
+Go in the activity tab for your webhook, there you will see the list of recent events.
+
+ ![image.png](https://s3.amazonaws.com/moonup/production/uploads/1671035382840-61d2f90c3c2083e1c08af22d.png)
+
+You will see the HTTP status code and the payload of the events. You can replay events too by clicking on the `replay` button!
+
+It is possible to change the url or secret of the webhook and then replay an event; it will send the payload to the updated URL.