Bucket Notifications - doc

Signed-off-by: Amit Prinz Setter <alphaprinz@gmail.com>

docs/NooBaaNonContainerized/ConfigFileCustomizations.md

@@ -449,6 +449,18 @@ Warning: After setting this configuration, NooBaa will skip schema validations a
     "LOG_TO_STDERR_ENABLED": false
     3. systemctl restart noobaa
     ```
+### 30. Notification log directory
+* <u>Key</u> `NOTIFICATION_LOG_DIR`
+* <u>Type</u> String
+* <u>Default</u> empty
+* <u>Description</u> Path to directory that will hold pending notifications to be sent,
+* <u>Steps</u>
+    ```
+    1. Open /path/to/config_dir/config.json file.
+    2. Set the config key -
+    Example:
+    "NOTIFICATION_LOG_DIR": "/etc/notif"
+    3. systemctl restart noobaa
 
 ## Config.json File Examples
 The following is an example of a config.json file - 

docs/bucket-notifications.md

@@ -0,0 +1,87 @@
+# Bucket Notifications
+
+## Bucket Notification Configuration
+
+Bucket's notifications can be configured with the s3api operation [put-bucket-notification-configuration](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/s3api/put-bucket-notification-configuration.html).
+Specify notifications under the "TopicConfigurations" field, which is an array of jsons, one for each notification.
+A notification json has these fields:
+- Id: Mandatory. A unique string identifying the notification configuration.
+- Events: Optional. An array of [events](https://docs.aws.amazon.com/AmazonS3/latest/userguide/notification-how-to-event-types-and-destinations.html) for which the notification is relevant.
+          If not specified, the notification is relevant for all events.
+- TopicArn: The connection file name. (To specify a Kafka target topic, see "Kafka Connection Fields" below).
+
+Example for a bucket's notification configuration, in a file:
+{
+    "TopicConfigurations": [
+        {
+	    "Id": "created_from_s3op",
+            "TopicArn": "connect.json",
+            "Events": [
+                "s3:ObjectCreated:*"
+            ]
+        }
+    ]
+}
+
+
+## Connection File
+A connection file contains some fields that specify the target notification server.
+The connection file name is specified in TopicArn field of the [notification configuration](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/s3api/put-bucket-notification-configuration.html)
+In a containerized environment, the operator will mount the secrets as file in the core pod (see operator doc for more info).
+In a non-containerized system, you must create the relevant file manually and place it in 'connect' config sub-directory.
+Connect file contains a single json with the fields specified below.
+
+### Common Connection Fields
+- name: A string identifying the connection (mandatory).
+- notification_protocol: One of: http, https, kafka (mandatory).
+
+### Http(s) Connection Fields
+- agent_request_object: Value is a JSON that is passed to to nodejs' http(s) agent (mandatory).
+Any field supported by nodejs' http(s) agent can be used, specifically 'host' and 'port'.
+A full list of options is [here](https://nodejs.org/docs/latest-v22.x/api/http.html#new-agentoptions).
+- request_options_object: Value is a JSON that is passed to nodejs' http(s) request (optional).
+Any field supported by nodejs' http(s) request option can be used, specifically 'auth' can be
+used for http simple auth. Value for 'auth' is of the syntax: <name>:<passowrd>.
+A full list of options is [here](https://nodejs.org/docs/latest-v22.x/api/http.html#httprequesturl-options-callback).
+
+### Kafka Connection Fields
+- metadata.broker.list: A CSV list of Kafka brokers (mandatory).
+- topic: A topic for the Kafka message (mandatory).
+
+## Event Types
+S3 spec lists several events and "sub events".
+
+The list of supported events are:
+
+- s3:ObjectCreated:*
+- s3:ObjectCreated:Put
+- s3:ObjectCreated:Post
+- s3:ObjectCreated:Copy
+- s3:ObjectCreated:CompleteMultipartUpload
+- s3:ObjectRemoved:*
+- s3:ObjectRemoved:Delete
+- s3:ObjectRemoved:DeleteMarkerCreated
+- s3:ObjectRestore:*
+- s3:ObjectRestore:Post
+- s3:ObjectRestore:Completed
+- s3:ObjectRestore:Delete
+- s3:ObjectTagging:*
+- s3:ObjectTagging:Put
+- s3:ObjectTagging:Delete
+- s3:LifecycleExpiration:*
+- s3:LifecycleExpiration:Delete
+- s3:LifecycleExpiration:DeleteMarkerCreated
+
+## Event Processing and Failure Handling
+Once NooBaa finds an event with a relevant notification configuration, the notification
+is written to a persistent file.
+Location of persistent files is determined by-
+- For containerized, the pvc specified in NooBaa Bucket Notification spec (see Operator docs for more info).
+- For NC, the env variable NOTIFICATION_LOG_DIR (see NC docs for more info).
+
+Files are processed by-
+- For containerized, files are contantly being processed in the background of the core pod.
+- For NC, files are processed by running manage_nsfs with 'notification' action.
+
+If a notification fails to be sent to the external server, it will be re-written to a persistent file.
+Once this new file is processed, NooBaa will try to re-send the failed notification.