Publish Events to Webhook

AIStor supports publishing bucket notification events to a webhook service endpoint.

Prerequisites

The AIStor mc command line tool

This procedure uses the mc command line tool for certain actions. See the mc Quickstart for installation instructions.

Add a webhook endpoint to an AIStor Server

The following procedure adds a new webhook service endpoint for supporting bucket notifications in an AIStor Server.

Add the webhook endpoint to AIStor.

You can configure a new webhook service endpoint using either environment variables or by setting runtime configuration settings.
Environment Variables
AIStor supports specifying the webhook service endpoint and associated configuration settings using environment variables. The minio server process applies the specified settings on its next startup.

The minimum required variables are:
- MINIO_NOTIFY_WEBHOOK_ENABLE
- MINIO_NOTIFY_WEBHOOK_ENDPOINT
The following example code sets all environment variables related to configuring a webhook service endpoint.
```
export MINIO_NOTIFY_WEBHOOK_ENABLE_<IDENTIFIER>="on"
export MINIO_NOTIFY_WEBHOOK_ENDPOINT_<IDENTIFIER>="ENDPOINT"
export MINIO_NOTIFY_WEBHOOK_AUTH_TOKEN_<IDENTIFIER>="<string>"
export MINIO_NOTIFY_WEBHOOK_QUEUE_DIR_<IDENTIFIER>="<string>"
export MINIO_NOTIFY_WEBHOOK_QUEUE_LIMIT_<IDENTIFIER>="<string>"
export MINIO_NOTIFY_WEBHOOK_CLIENT_CERT_<IDENTIFIER>="<string>"
export MINIO_NOTIFY_WEBHOOK_CLIENT_KEY_<IDENTIFIER>="<string>"
export MINIO_NOTIFY_WEBHOOK_COMMENT_<IDENTIFIER>="<string>"
```
- Replace <IDENTIFIER> with a unique descriptive string for the webhook service endpoint. Use the same <IDENTIFIER> value for all environment variables related to the new target service endpoint. The following examples assume an identifier of PRIMARY.
  
  If the specified <IDENTIFIER> matches an existing webhook service endpoint on the AIStor Server, the new settings override any existing settings for that endpoint. Use mc admin config get notify_webhook to review the currently configured webhook endpoints on the AIStor Server.
- Replace <ENDPOINT> with the URL of the webhook service endpoint. For example:
  
  https://webhook.example.com
See Webhook Service for Bucket Notifications for complete documentation on each environment variable.
Configuration Settings
AIStor supports adding or updating webhook endpoints on a running minio server process using the mc admin config set command and the notify_webhook configuration key. You must restart the minio server process to apply any new or updated configuration settings.

The minimum required setting is notify_webhook endpoint.

The following example code sets all settings related to configuring a webhook service endpoint.
```
mc admin config set ALIAS notify_webhook:IDENTIFIER \
   endpoint="<ENDPOINT>" \
   auth_token="<string>" \
   queue_dir="<string>" \
   queue_limit="<string>" \
   client_cert="<string>" \
   client_key="<string>" \
   comment="<string>"
```
- Replace IDENTIFIER with a unique descriptive string for the webhook service endpoint. The following examples in this procedure assume an identifier of PRIMARY.
  
  If the specified IDENTIFIER matches an existing webhook service endpoint on the AIStor Server, the new settings override any existing settings for that endpoint. Use mc admin config get notify_webhook to review the currently configured webhook endpoints on the AIStor Server.
- Replace ENDPOINT with the URL of the webhook service endpoint. For example:
  
  https://webhook.example.com
See Webhook Bucket Notification Configuration Settings for complete documentation on each setting.
If you define both environment variables and configuration settings for the deployment, the settings defined by environment variables are used.
Restart the AIStor Server.

You must restart the AIStor Server to apply the configuration changes. Use the mc admin service restart command to restart the deployment.
```
mc admin service restart ALIAS
```
Replace ALIAS with the alias of the deployment to restart.

The minio server process prints a line on startup for each configured webhook target similar to the following:
```
SQS ARNs: arn:minio:sqs::primary:webhook
```
You must specify the ARN resource when configuring bucket notifications with the associated webhook deployment as a target.
Configure bucket notifications using the webhook endpoint as a target.

Use the mc event add command to add a new bucket notification event with the configured webhook service as a target:
```
mc event add ALIAS/BUCKET arn:minio:sqs::primary:webhook \
  --event EVENTS
```
- Replace ALIAS with the alias of an AIStor Server.
- Replace BUCKET with the name of the bucket in which to configure the event.
- Replace EVENTS with a comma-separated list of events for which AIStor triggers notifications.
Use mc event ls to view all configured bucket events for a given notification target:
```
mc event ls ALIAS/BUCKET arn:minio:sqs::primary:webhook
```
Validate the configured events.

Perform an action on the bucket for which you configured the new event and check the webhook service for the notification data. The action required depends on which events were specified when configuring the bucket notification.

For example, if the bucket notification configuration includes the s3:ObjectCreated:Put event, you can use the mc cp command to create a new object in the bucket and trigger a notification.
```
mc cp ~/data/new-object.txt ALIAS/BUCKET
```

Update a webhook endpoint in an AIStor Server

The following procedure updates an existing webhook service endpoint for supporting bucket notifications in an AIStor Server.

List configured webhook endpoints in the deployment.

Use the mc admin config get command to list the currently configured webhook service endpoints in the deployment:
```
mc admin config get ALIAS notify_webhook
```
Replace ALIAS with the alias of the AIStor Server.

The command output resembles the following:
```
notify_webhook:primary endpoint="https://webhook.example.com" auth_token="" queue_limit="0" queue_dir="" client_cert="" client_key=""
notify_webhook:secondary endpoint="https://webhook.example.com" auth_token="" queue_limit="0" queue_dir="" client_cert="" client_key=""
```
- notify_webhook is the top-level configuration key for a Webhook Service Notification Settings.
- endpoint specifies the webhook service endpoint for the given notify_webhook key.
- The notify_webhook:<IDENTIFIER> suffix describes the unique identifier for that webhook service endpoint.
Note the identifier for the webhook service endpoint you want to update for the next step.
Update the webhook endpoint.

Use the mc admin config set command to set the new configuration for the webhook service endpoint:
```
mc admin config set ALIAS notify_webhook:IDENTIFIER \
   endpoint="<ENDPOINT>" \
   auth_token="<string>" \
   queue_dir="<string>" \
   queue_limit="<string>" \
   client_cert="<string>" \
   client_key="<string>" \
   comment="<string>"
```
- The notify_webhook endpoint configuration setting is the minimum required for a webhook service endpoint.
- All other configuration settings are optional.
See Webhook Service Notification Settings for a complete list of webhook configuration settings.
Restart the AIStor Server.

You must restart the AIStor Server to apply the configuration changes. Use the mc admin service restart command to restart the deployment.
```
mc admin service restart ALIAS
```
Replace ALIAS with the alias of the deployment to restart.

The minio server process prints a line on startup for each configured webhook target similar to the following:
```
SQS ARNs: arn:minio:sqs::primary:webhook
```
Validate the changes.

Perform an action on a bucket which has an event configuration using the updated webhook service endpoint and check the webhook service for the notification data. The action required depends on which events were specified when configuring the bucket notification.

For example, if the bucket notification configuration includes the s3:ObjectCreated:Put event, you can use the mc cp command to create a new object in the bucket and trigger a notification.
```
mc cp ~/data/new-object.txt ALIAS/BUCKET
```