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minio/docs/bucket/notifications/README.md

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MinIO Bucket Notification Guide Slack

Events occurring on objects in a bucket can be monitored using bucket event notifications. Event types supported by MinIO server are

Supported Event Types
s3:ObjectCreated:Put s3:ObjectCreated:CompleteMultipartUpload s3:ObjectAccessed:Head
s3:ObjectCreated:Post s3:ObjectRemoved:Delete
s3:ObjectCreated:Copy s3:ObjectAccessed:Get

Use client tools like mc to set and listen for event notifications using the event sub-command. MinIO SDK's BucketNotification APIs can also be used. The notification message MinIO sends to publish an event is a JSON message with the following structure.

Bucket events can be published to the following targets:

Supported Notification Targets
AMQP Redis MySQL
MQTT NATS Apache Kafka
Elasticsearch PostgreSQL Webhooks
NSQ

Prerequisites

  • Install and configure MinIO Server from here.
  • Install and configure MinIO Client from here.

Publish MinIO events via AMQP

Install RabbitMQ from here.

Step 1: Add AMQP endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. The AMQP configuration is located in the amqp key under the notify top-level key. Create a configuration key-value pair here for your AMQP instance. The key is a name for your AMQP endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
url string (Required) AMQP server endpoint, e.g. amqp://myuser:mypassword@localhost:5672
exchange string Name of the exchange.
routingKey string Routing key for publishing.
exchangeType string Kind of exchange.
deliveryMode uint8 Delivery mode for publishing. 0 or 1 - transient; 2 - persistent.
mandatory bool Publishing related bool.
immediate bool Publishing related bool.
durable bool Exchange declaration related bool.
internal bool Exchange declaration related bool.
noWait bool Exchange declaration related bool.
autoDeleted bool Exchange declaration related bool.

An example configuration for RabbitMQ is shown below:

"amqp": {
    "1": {
        "enable": true,
        "url": "amqp://myuser:mypassword@localhost:5672",
        "exchange": "bucketevents",
        "routingKey": "bucketlogs",
        "exchangeType": "fanout",
        "deliveryMode": 0,
        "mandatory": false,
        "immediate": false,
        "durable": false,
        "internal": false,
        "noWait": false,
        "autoDeleted": false
    }
}

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the AMQP configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:amqp at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

MinIO supports all the exchanges available in RabbitMQ. For this setup, we are using fanout exchange.

Note that, you can add as many AMQP server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the AMQP instance and an object of per-server configuration parameters.

Step 2: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded or deleted images bucket on myminio server. Here ARN value is arn:minio:sqs::1:amqp. To understand more about ARN please follow AWS ARN documentation.

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:amqp --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:amqp s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 3: Test on RabbitMQ

The python program below waits on the queue exchange bucketevents and prints event notifications on the console. We use Pika Python Client library to do this.

#!/usr/bin/env python
import pika

connection = pika.BlockingConnection(pika.ConnectionParameters(
        host='localhost'))
channel = connection.channel()

channel.exchange_declare(exchange='bucketevents',
                         exchange_type='fanout')

result = channel.queue_declare(exclusive=False)
queue_name = result.method.queue

channel.queue_bind(exchange='bucketevents',
                   queue=queue_name)

print(' [*] Waiting for logs. To exit press CTRL+C')

def callback(ch, method, properties, body):
    print(" [x] %r" % body)

channel.basic_consume(callback,
                      queue=queue_name,
                      no_ack=False)

channel.start_consuming()

Execute this example python program to watch for RabbitMQ events on the console.

python rabbit.py

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

You should receive the following event notification via RabbitMQ once the upload completes.

python rabbit.py
'{"Records":[{"eventVersion":"2.0","eventSource":"aws:s3","awsRegion":"","eventTime":"2016–09–08T22:34:38.226Z","eventName":"s3:ObjectCreated:Put","userIdentity":{"principalId":"minio"},"requestParameters":{"sourceIPAddress":"10.1.10.150:44576"},"responseElements":{},"s3":{"s3SchemaVersion":"1.0","configurationId":"Config","bucket":{"name":"images","ownerIdentity":{"principalId":"minio"},"arn":"arn:aws:s3:::images"},"object":{"key":"myphoto.jpg","size":200436,"sequencer":"147279EAF9F40933"}}}],"level":"info","msg":"","time":"2016–09–08T15:34:38–07:00"}'

Publish MinIO events MQTT

Install an MQTT Broker from here.

Step 1: Add MQTT endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. The MQTT configuration is located in the mqtt key under the notify top-level key. Create a configuration key-value pair here for your MQTT instance. The key is a name for your MQTT endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
broker string (Required) MQTT server endpoint, e.g. tcp://localhost:1883
topic string (Required) Name of the MQTT topic to publish on, e.g. minio
qos int Set the Quality of Service Level
username string Username to connect to the MQTT server (if required)
password string Password to connect to the MQTT server (if required)
queueDir string Persistent store for events when MQTT broker is offline
queueLimit int Set the maximum event limit for the persistent store. The default limit is 10000

An example configuration for MQTT is shown below:

"mqtt": {
    "1": {
        "enable": true,
        "broker": "tcp://localhost:1883",
        "topic": "minio",
        "qos": 1,
        "username": "",
        "password": "",
        "queueDir": "",
        "queueLimit": 0
    }
}

MinIO supports persistent event store. The persistent store will backup events when the MQTT broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the MQTT configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:mqtt at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

MinIO supports any MQTT server that supports MQTT 3.1 or 3.1.1 and can connect to them over TCP, TLS, or a Websocket connection using tcp://, tls://, or ws:// respectively as the scheme for the broker url. See the Go Client documentation for more information.

Note that, you can add as many MQTT server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the MQTT instance and an object of per-server configuration parameters.

Step 2: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded or deleted images bucket on myminio server. Here ARN value is arn:minio:sqs::1:mqtt.

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:mqtt --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:amqp s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 3: Test on MQTT

The python program below waits on mqtt topic /minio and prints event notifications on the console. We use paho-mqtt library to do this.

#!/usr/bin/env python3
from __future__ import print_function
import paho.mqtt.client as mqtt

# This is the Subscriber

def on_connect(client, userdata, flags, rc):
  print("Connected with result code "+str(rc))
  # qos level is set to 1
  client.subscribe("minio", 1)

def on_message(client, userdata, msg):
    print(msg.payload)

# client_id is a randomly generated unique ID for the mqtt broker to identify the connection.
client = mqtt.Client(client_id="myclientid",clean_session=False)

client.on_connect = on_connect
client.on_message = on_message

client.connect("localhost",1883,60)
client.loop_forever()

Execute this example python program to watch for MQTT events on the console.

python mqtt.py

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

You should receive the following event notification via MQTT once the upload completes.

python mqtt.py
{“Records”:[{“eventVersion”:”2.0",”eventSource”:”aws:s3",”awsRegion”:”",”eventTime”:”2016–09–08T22:34:38.226Z”,”eventName”:”s3:ObjectCreated:Put”,”userIdentity”:{“principalId”:”minio”},”requestParameters”:{“sourceIPAddress”:”10.1.10.150:44576"},”responseElements”:{},”s3":{“s3SchemaVersion”:”1.0",”configurationId”:”Config”,”bucket”:{“name”:”images”,”ownerIdentity”:{“principalId”:”minio”},”arn”:”arn:aws:s3:::images”},”object”:{“key”:”myphoto.jpg”,”size”:200436,”sequencer”:”147279EAF9F40933"}}}],”level”:”info”,”msg”:””,”time”:”2016–09–08T15:34:38–07:00"}

Publish MinIO events via Elasticsearch

Install Elasticsearch server.

This notification target supports two formats: namespace and access.

When the namespace format is used, MinIO synchronizes objects in the bucket with documents in the index. For each event in the MinIO, the server creates a document with the bucket and object name from the event as the document ID. Other details of the event are stored in the body of the document. Thus if an existing object is over-written in MinIO, the corresponding document in the Elasticsearch index is updated. If an object is deleted, the corresponding document is deleted from the index.

When the access format is used, MinIO appends events as documents in an Elasticsearch index. For each event, a document with the event details, with the timestamp of document set to the event's timestamp is appended to an index. The ID of the documented is randomly generated by Elasticsearch. No documents are deleted or modified in this format.

The steps below show how to use this notification target in namespace format. The other format is very similar and is omitted for brevity.

Step 1: Ensure minimum requirements are met

MinIO requires a 5.x series version of Elasticsearch. This is the latest major release series. Elasticsearch provides version upgrade migration guidelines here.

Step 2: Add Elasticsearch endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. The Elasticsearch configuration is located in the elasticsearch key under the notify top-level key. Create a configuration key-value pair here for your Elasticsearch instance. The key is a name for your Elasticsearch endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
format string (Required) Either namespace or access.
url string (Required) The Elasticsearch server's address, with optional authentication info. For example: http://localhost:9200 or with authentication info http://elastic:MagicWord@127.0.0.1:9200.
index string (Required) The name of an Elasticsearch index in which MinIO will store documents.
queueDir string Persistent store for events when Elasticsearch broker is offline
queueLimit int Set the maximum event limit for the persistent store. The default limit is 10000

An example of Elasticsearch configuration is as follows:

"elasticsearch": {
    "1": {
        "enable": true,
        "format": "namespace",
        "url": "http://127.0.0.1:9200",
        "index": "minio_events",
        "queueDir": "",
        "queueLimit": 0
    }
},

Minio supports persistent event store. The persistent store will backup events when the Elasticsearch broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

If Elasticsearch has authentication enabled, the credentials can be supplied to MinIO via the url parameter formatted as PROTO://USERNAME:PASSWORD@ELASTICSEARCH_HOST:PORT.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the Elasticsearch configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:elasticsearch at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

Note that, you can add as many Elasticsearch server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the Elasticsearch instance and an object of per-server configuration parameters.

Step 3: Enable bucket notification using MinIO client

We will now enable bucket event notifications on a bucket named images. Whenever a JPEG image is created/overwritten, a new document is added or an existing document is updated in the Elasticsearch index configured above. When an existing object is deleted, the corresponding document is deleted from the index. Thus, the rows in the Elasticsearch index, reflect the .jpg objects in the images bucket.

To configure this bucket notification, we need the ARN printed by MinIO in the previous step. Additional information about ARN is available here.

With the mc tool, the configuration is very simple to add. Let us say that the MinIO server is aliased as myminio in our mc configuration. Execute the following:

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:elasticsearch --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:elasticsearch s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 4: Test on Elasticsearch

Upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

Use curl to view contents of minio_events index.

$ curl  "http://localhost:9200/minio_events/_search?pretty=true"
{
  "took" : 40,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "minio_events",
        "_type" : "event",
        "_id" : "images/myphoto.jpg",
        "_score" : 1.0,
        "_source" : {
          "Records" : [
            {
              "eventVersion" : "2.0",
              "eventSource" : "minio:s3",
              "awsRegion" : "",
              "eventTime" : "2017-03-30T08:00:41Z",
              "eventName" : "s3:ObjectCreated:Put",
              "userIdentity" : {
                "principalId" : "minio"
              },
              "requestParameters" : {
                "sourceIPAddress" : "127.0.0.1:38062"
              },
              "responseElements" : {
                "x-amz-request-id" : "14B09A09703FC47B",
                "x-minio-origin-endpoint" : "http://192.168.86.115:9000"
              },
              "s3" : {
                "s3SchemaVersion" : "1.0",
                "configurationId" : "Config",
                "bucket" : {
                  "name" : "images",
                  "ownerIdentity" : {
                    "principalId" : "minio"
                  },
                  "arn" : "arn:aws:s3:::images"
                },
                "object" : {
                  "key" : "myphoto.jpg",
                  "size" : 6474,
                  "eTag" : "a3410f4f8788b510d6f19c5067e60a90",
                  "sequencer" : "14B09A09703FC47B"
                }
              },
              "source" : {
                "host" : "127.0.0.1",
                "port" : "38062",
                "userAgent" : "MinIO (linux; amd64) minio-go/2.0.3 mc/2017-02-15T17:57:25Z"
              }
            }
          ]
        }
      }
    ]
  }
}

This output shows that a document has been created for the event in Elasticsearch.

Here we see that the document ID is the bucket and object name. In case access format was used, the document ID would be automatically generated by Elasticsearch.

Publish MinIO events via Redis

Install Redis server. For illustrative purposes, we have set the database password as "yoursecret".

This notification target supports two formats: namespace and access.

When the namespace format is used, MinIO synchronizes objects in the bucket with entries in a hash. For each entry, the key is formatted as "bucketName/objectName" for an object that exists in the bucket, and the value is the JSON-encoded event data about the operation that created/replaced the object in MinIO. When objects are updated or deleted, the corresponding entry in the hash is also updated or deleted.

When the access format is used, MinIO appends events to a list using RPUSH. Each item in the list is a JSON encoded list with two items, where the first item is a timestamp string, and the second item is a JSON object containing event data about the operation that happened in the bucket. No entries appended to the list are updated or deleted by MinIO in this format.

The steps below show how to use this notification target in namespace and access format.

Step 1: Add Redis endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format.The Redis configuration is located in the redis key under the notify top-level key. Create a configuration key-value pair here for your Redis instance. The key is a name for your Redis endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
format string (Required) Either namespace or access.
address string (Required) The Redis server's address. For example: localhost:6379.
password string (Optional) The Redis server's password.
key string (Required) The name of the redis key under which events are stored. A hash is used in case of namespace format and a list in case of access format.

An example of Redis configuration is as follows:

"redis": {
    "1": {
        "enable": true,
        "format": "namespace",
        "address": "127.0.0.1:6379",
        "password": "yoursecret",
        "key": "bucketevents",
        "queueDir": "",
        "queueLimit": 0
    }
}

MinIO supports persistent event store. The persistent store will backup events when the Redis broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the Redis configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:redis at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

Note that, you can add as many Redis server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the Redis instance and an object of per-server configuration parameters.

Step 2: Enable bucket notification using MinIO client

We will now enable bucket event notifications on a bucket named images. Whenever a JPEG image is created/overwritten, a new key is added or an existing key is updated in the Redis hash configured above. When an existing object is deleted, the corresponding key is deleted from the Redis hash. Thus, the rows in the Redis hash, reflect the .jpg objects in the images bucket.

To configure this bucket notification, we need the ARN printed by MinIO in the previous step. Additional information about ARN is available here.

With the mc tool, the configuration is very simple to add. Let us say that the MinIO server is aliased as myminio in our mc configuration. Execute the following:

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:redis --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:redis s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 3: Test on Redis

Start the redis-cli Redis client program to inspect the contents in Redis. Run the monitor Redis command. This prints each operation performed on Redis as it occurs.

redis-cli -a yoursecret
127.0.0.1:6379> monitor
OK

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

In the previous terminal, you will now see the operation that MinIO performs on Redis:

127.0.0.1:6379> monitor
OK
1490686879.650649 [0 172.17.0.1:44710] "PING"
1490686879.651061 [0 172.17.0.1:44710] "HSET" "minio_events" "images/myphoto.jpg" "{\"Records\":[{\"eventVersion\":\"2.0\",\"eventSource\":\"minio:s3\",\"awsRegion\":\"\",\"eventTime\":\"2017-03-28T07:41:19Z\",\"eventName\":\"s3:ObjectCreated:Put\",\"userIdentity\":{\"principalId\":\"minio\"},\"requestParameters\":{\"sourceIPAddress\":\"127.0.0.1:52234\"},\"responseElements\":{\"x-amz-request-id\":\"14AFFBD1ACE5F632\",\"x-minio-origin-endpoint\":\"http://192.168.86.115:9000\"},\"s3\":{\"s3SchemaVersion\":\"1.0\",\"configurationId\":\"Config\",\"bucket\":{\"name\":\"images\",\"ownerIdentity\":{\"principalId\":\"minio\"},\"arn\":\"arn:aws:s3:::images\"},\"object\":{\"key\":\"myphoto.jpg\",\"size\":2586,\"eTag\":\"5d284463f9da279f060f0ea4d11af098\",\"sequencer\":\"14AFFBD1ACE5F632\"}},\"source\":{\"host\":\"127.0.0.1\",\"port\":\"52234\",\"userAgent\":\"MinIO (linux; amd64) minio-go/2.0.3 mc/2017-02-15T17:57:25Z\"}}]}"

Here we see that MinIO performed HSET on minio_events key.

In case, access format was used, then minio_events would be a list, and the MinIO server would have performed an RPUSH to append to the list. A consumer of this list would ideally use BLPOP to remove list items from the left-end of the list.

Publish MinIO events via NATS

Install NATS from here.

Step 1: Add NATS endpoint to MinIO

The NATS configuration block in config.json is as follows:

"nats": {
    "1": {
        "enable": true,
        "address": "0.0.0.0:4222",
        "subject": "bucketevents",
        "username": "yourusername",
        "password": "yoursecret",
        "token": "",
        "secure": false,
        "pingInterval": 0,
        "queueDir": "",
        "queueLimit": 0,
        "streaming": {
            "enable": false,
            "clusterID": "",
            "async": false,
            "maxPubAcksInflight": 0
        }
    }
},

MinIO supports persistent event store. The persistent store will backup events when the NATS broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the NATS configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart MinIO server to reflect config changes. bucketevents is the subject used by NATS in this example.

$ mc admin config set myminio < /tmp/myconfig

MinIO server also supports NATS Streaming mode that offers additional functionality like At-least-once-delivery, and Publisher rate limiting. To configure MinIO server to send notifications to NATS Streaming server, update the MinIO server configuration file as follows:

"nats": {
    "1": {
        "enable": true,
        "address": "0.0.0.0:4222",
        "subject": "bucketevents",
        "username": "yourusername",
        "password": "yoursecret",
        "token": "",
        "secure": false,
        "pingInterval": 0,
        "queueDir": "",
        "queueLimit": 0,
        "streaming": {
            "enable": true,
            "clusterID": "test-cluster",
            "async": true,
            "maxPubAcksInflight": 10
        }
    }
},

Read more about sections clusterID, clientID on NATS documentation. Section maxPubAcksInflight is explained here.

Step 2: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded or deleted from images bucket on myminio server. Here ARN value is arn:minio:sqs::1:nats. To understand more about ARN please follow AWS ARN documentation.

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:nats --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:nats s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 3: Test on NATS

If you use NATS server, check out this sample program below to log the bucket notification added to NATS.

package main

// Import Go and NATS packages
import (
	"log"
	"runtime"

	"github.com/nats-io/nats.go"
)

func main() {

	// Create server connection
	natsConnection, _ := nats.Connect("nats://yourusername:yoursecret@localhost:4222")
	log.Println("Connected")

	// Subscribe to subject
	log.Printf("Subscribing to subject 'bucketevents'\n")
	natsConnection.Subscribe("bucketevents", func(msg *nats.Msg) {

		// Handle the message
		log.Printf("Received message '%s\n", string(msg.Data)+"'")
	})

	// Keep the connection alive
	runtime.Goexit()
}

go run nats.go
2016/10/12 06:39:18 Connected
2016/10/12 06:39:18 Subscribing to subject 'bucketevents'

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

The example nats.go program prints event notification to console.

go run nats.go
2016/10/12 06:51:26 Connected
2016/10/12 06:51:26 Subscribing to subject 'bucketevents'
2016/10/12 06:51:33 Received message '{"EventType":"s3:ObjectCreated:Put","Key":"images/myphoto.jpg","Records":[{"eventVersion":"2.0","eventSource":"aws:s3","awsRegion":"","eventTime":"2016-10-12T13:51:33Z","eventName":"s3:ObjectCreated:Put","userIdentity":{"principalId":"minio"},"requestParameters":{"sourceIPAddress":"[::1]:57106"},"responseElements":{},"s3":{"s3SchemaVersion":"1.0","configurationId":"Config","bucket":{"name":"images","ownerIdentity":{"principalId":"minio"},"arn":"arn:aws:s3:::images"},"object":{"key":"myphoto.jpg","size":56060,"eTag":"1d97bf45ecb37f7a7b699418070df08f","sequencer":"147CCD1AE054BFD0"}}}],"level":"info","msg":"","time":"2016-10-12T06:51:33-07:00"}

If you use NATS Streaming server, check out this sample program below to log the bucket notification added to NATS.

package main

// Import Go and NATS packages
import (
	"fmt"
	"runtime"

	"github.com/nats-io/stan.go"
)

func main() {

	var stanConnection stan.Conn

	subscribe := func() {
		fmt.Printf("Subscribing to subject 'bucketevents'\n")
		stanConnection.Subscribe("bucketevents", func(m *stan.Msg) {

			// Handle the message
			fmt.Printf("Received a message: %s\n", string(m.Data))
		})
	}


	stanConnection, _ = stan.Connect("test-cluster", "test-client", stan.NatsURL("nats://yourusername:yoursecret@0.0.0.0:4222"), stan.SetConnectionLostHandler(func(c stan.Conn, _ error) {
		go func() {
			for {
				// Reconnect if the connection is lost.
				if stanConnection == nil || stanConnection.NatsConn() == nil ||  !stanConnection.NatsConn().IsConnected() {
					stanConnection, _ = stan.Connect("test-cluster", "test-client", stan.NatsURL("nats://yourusername:yoursecret@0.0.0.0:4222"), stan.SetConnectionLostHandler(func(c stan.Conn, _ error) {
						if c.NatsConn() != nil {
							c.NatsConn().Close()
						}
						_ = c.Close()
					}))
					if stanConnection != nil {
						subscribe()
					}

				}
			}

		}()
	}))

	// Subscribe to subject
	subscribe()

	// Keep the connection alive
	runtime.Goexit()
}


go run nats.go
2017/07/07 11:47:40 Connected
2017/07/07 11:47:40 Subscribing to subject 'bucketevents'

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

The example nats.go program prints event notification to console.

Received a message: {"EventType":"s3:ObjectCreated:Put","Key":"images/myphoto.jpg","Records":[{"eventVersion":"2.0","eventSource":"minio:s3","awsRegion":"","eventTime":"2017-07-07T18:46:37Z","eventName":"s3:ObjectCreated:Put","userIdentity":{"principalId":"minio"},"requestParameters":{"sourceIPAddress":"192.168.1.80:55328"},"responseElements":{"x-amz-request-id":"14CF20BD1EFD5B93","x-minio-origin-endpoint":"http://127.0.0.1:9000"},"s3":{"s3SchemaVersion":"1.0","configurationId":"Config","bucket":{"name":"images","ownerIdentity":{"principalId":"minio"},"arn":"arn:aws:s3:::images"},"object":{"key":"myphoto.jpg","size":248682,"eTag":"f1671feacb8bbf7b0397c6e9364e8c92","contentType":"image/jpeg","userDefined":{"content-type":"image/jpeg"},"versionId":"1","sequencer":"14CF20BD1EFD5B93"}},"source":{"host":"192.168.1.80","port":"55328","userAgent":"MinIO (linux; amd64) minio-go/2.0.4 mc/DEVELOPMENT.GOGET"}}],"level":"info","msg":"","time":"2017-07-07T11:46:37-07:00"}

Publish MinIO events via PostgreSQL

Install PostgreSQL database server. For illustrative purposes, we have set the "postgres" user password as password and created a database called minio_events to store the events.

This notification target supports two formats: namespace and access.

When the namespace format is used, MinIO synchronizes objects in the bucket with rows in the table. It creates rows with two columns: key and value. The key is the bucket and object name of an object that exists in MinIO. The value is JSON encoded event data about the operation that created/replaced the object in MinIO. When objects are updated or deleted, the corresponding row from this table is updated or deleted respectively.

When the access format is used, MinIO appends events to a table. It creates rows with two columns: event_time and event_data. The event_time is the time at which the event occurred in the MinIO server. The event_data is the JSON encoded event data about the operation on an object. No rows are deleted or modified in this format.

The steps below show how to use this notification target in namespace format. The other format is very similar and is omitted for brevity.

Step 1: Ensure minimum requirements are met

MinIO requires PostgreSQL version 9.5 or above. MinIO uses the INSERT ON CONFLICT (aka UPSERT) feature, introduced in version 9.5 and the JSONB data-type introduced in version 9.4.

Step 2: Add PostgreSQL endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. The PostgreSQL configuration is located in the postgresql key under the notify top-level key. Create a configuration key-value pair here for your PostgreSQL instance. The key is a name for your PostgreSQL endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
format string (Required) Either namespace or access.
connectionString string (Optional) Connection string parameters for the PostgreSQL server. Can be used to set sslmode for example.
table string (Required) Table name in which events will be stored/updated. If the table does not exist, the MinIO server creates it at start-up.
host string (Optional) Host name of the PostgreSQL server. Defaults to localhost. IPv6 host should be enclosed with [ and ]
port string (Optional) Port on which to connect to PostgreSQL server. Defaults to 5432.
user string (Optional) Database user name. Defaults to user running the server process.
password string (Optional) Database password.
database string (Optional) Database name.

An example of PostgreSQL configuration is as follows:

"postgresql": {
    "1": {
        "enable": true,
        "format": "namespace",
        "connectionString": "sslmode=disable",
        "table": "bucketevents",
        "host": "127.0.0.1",
        "port": "5432",
        "user": "postgres",
        "password": "password",
        "database": "minio_events",
        "queueDir": "",
        "queueLimit": 0
    }
}

MinIO supports persistent event store. The persistent store will backup events when the PostgreSQL connection goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

Note that for illustration here, we have disabled SSL. In the interest of security, for production this is not recommended. To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the Postgres configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:postgresql at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

Note that, you can add as many PostgreSQL server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the PostgreSQL instance and an object of per-server configuration parameters.

Step 3: Enable bucket notification using MinIO client

We will now enable bucket event notifications on a bucket named images. Whenever a JPEG image is created/overwritten, a new row is added or an existing row is updated in the PostgreSQL configured above. When an existing object is deleted, the corresponding row is deleted from the PostgreSQL table. Thus, the rows in the PostgreSQL table, reflect the .jpg objects in the images bucket.

To configure this bucket notification, we need the ARN printed by MinIO in the previous step. Additional information about ARN is available here.

With the mc tool, the configuration is very simple to add. Let us say that the MinIO server is aliased as myminio in our mc configuration. Execute the following:

# Create bucket named `images` in myminio
mc mb myminio/images
# Add notification configuration on the `images` bucket using the MySQL ARN. The --suffix argument filters events.
mc event add myminio/images arn:minio:sqs::1:postgresql --suffix .jpg
# Print out the notification configuration on the `images` bucket.
mc event list myminio/images
mc event list myminio/images
arn:minio:sqs::1:postgresql s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 4: Test on PostgreSQL

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

Open PostgreSQL terminal to list the rows in the bucketevents table.

$ psql -h 127.0.0.1 -U postgres -d minio_events
minio_events=# select * from bucketevents;

key                 |                      value
--------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 images/myphoto.jpg | {"Records": [{"s3": {"bucket": {"arn": "arn:aws:s3:::images", "name": "images", "ownerIdentity": {"principalId": "minio"}}, "object": {"key": "myphoto.jpg", "eTag": "1d97bf45ecb37f7a7b699418070df08f", "size": 56060, "sequencer": "147CE57C70B31931"}, "configurationId": "Config", "s3SchemaVersion": "1.0"}, "awsRegion": "", "eventName": "s3:ObjectCreated:Put", "eventTime": "2016-10-12T21:18:20Z", "eventSource": "aws:s3", "eventVersion": "2.0", "userIdentity": {"principalId": "minio"}, "responseElements": {}, "requestParameters": {"sourceIPAddress": "[::1]:39706"}}]}
(1 row)

Publish MinIO events via MySQL

Install MySQL from here. For illustrative purposes, we have set the root password as password and created a database called miniodb to store the events.

This notification target supports two formats: namespace and access.

When the namespace format is used, MinIO synchronizes objects in the bucket with rows in the table. It creates rows with two columns: key_name and value. The key_name is the bucket and object name of an object that exists in MinIO. The value is JSON encoded event data about the operation that created/replaced the object in MinIO. When objects are updated or deleted, the corresponding row from this table is updated or deleted respectively.

When the access format is used, MinIO appends events to a table. It creates rows with two columns: event_time and event_data. The event_time is the time at which the event occurred in the MinIO server. The event_data is the JSON encoded event data about the operation on an object. No rows are deleted or modified in this format.

The steps below show how to use this notification target in namespace format. The other format is very similar and is omitted for brevity.

Step 1: Ensure minimum requirements are met

MinIO requires MySQL version 5.7.8 or above. MinIO uses the JSON data-type introduced in version 5.7.8. We tested this setup on MySQL 5.7.17.

Step 2: Add MySQL server endpoint configuration to MinIO

The MinIO server configuration file is stored on the backend in json format. The MySQL configuration is located in the mysql key under the notify top-level key. Create a configuration key-value pair here for your MySQL instance. The key is a name for your MySQL endpoint, and the value is a collection of key-value parameters described in the table below.

Parameter Type Description
enable bool (Required) Is this server endpoint configuration active/enabled?
format string (Required) Either namespace or access.
dsnString string (Optional) Data-Source-Name connection string for the MySQL server. If not specified, the connection information specified by the host, port, user, password and database parameters are used.
table string (Required) Table name in which events will be stored/updated. If the table does not exist, the MinIO server creates it at start-up.
host string Host name of the MySQL server (used only if dsnString is empty).
port string Port on which to connect to the MySQL server (used only if dsnString is empty).
user string Database user-name (used only if dsnString is empty).
password string Database password (used only if dsnString is empty).
database string Database name (used only if dsnString is empty).

An example of MySQL configuration is as follows:

"mysql": {
       "1": {
           "enable": true,
           "dsnString": "",
           "format": "namespace",
           "table": "minio_images",
           "host": "172.17.0.1",
           "port": "3306",
           "user": "root",
           "password": "password",
           "database": "miniodb",
           "queueDir": "",
           "queueLimit": 0
       }
}

MinIO supports persistent event store. The persistent store will backup events when the MySQL connection goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the MySQL configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:mysql at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

Note that, you can add as many MySQL server endpoint configurations as needed by providing an identifier (like "1" in the example above) for the MySQL instance and an object of per-server configuration parameters.

Step 3: Enable bucket notification using MinIO client

We will now setup bucket notifications on a bucket named images. Whenever a JPEG image object is created/overwritten, a new row is added or an existing row is updated in the MySQL table configured above. When an existing object is deleted, the corresponding row is deleted from the MySQL table. Thus, the rows in the MySQL table, reflect the .jpg objects in the images bucket.

To configure this bucket notification, we need the ARN printed by MinIO in the previous step. Additional information about ARN is available here.

With the mc tool, the configuration is very simple to add. Let us say that the MinIO server is aliased as myminio in our mc configuration. Execute the following:

# Create bucket named `images` in myminio
mc mb myminio/images
# Add notification configuration on the `images` bucket using the MySQL ARN. The --suffix argument filters events.
mc event add myminio/images arn:minio:sqs::1:postgresql --suffix .jpg
# Print out the notification configuration on the `images` bucket.
mc event list myminio/images
arn:minio:sqs::1:postgresql s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 4: Test on MySQL

Open another terminal and upload a JPEG image into images bucket:

mc cp myphoto.jpg myminio/images

Open MySQL terminal and list the rows in the minio_images table.

$ mysql -h 172.17.0.1 -P 3306 -u root -p miniodb
mysql> select * from minio_images;
+--------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| key_name           | value                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
+--------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| images/myphoto.jpg | {"Records": [{"s3": {"bucket": {"arn": "arn:aws:s3:::images", "name": "images", "ownerIdentity": {"principalId": "minio"}}, "object": {"key": "myphoto.jpg", "eTag": "467886be95c8ecfd71a2900e3f461b4f", "size": 26, "sequencer": "14AC59476F809FD3"}, "configurationId": "Config", "s3SchemaVersion": "1.0"}, "awsRegion": "", "eventName": "s3:ObjectCreated:Put", "eventTime": "2017-03-16T11:29:00Z", "eventSource": "aws:s3", "eventVersion": "2.0", "userIdentity": {"principalId": "minio"}, "responseElements": {"x-amz-request-id": "14AC59476F809FD3", "x-minio-origin-endpoint": "http://192.168.86.110:9000"}, "requestParameters": {"sourceIPAddress": "127.0.0.1:38260"}}]} |
+--------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)

Publish MinIO events via Kafka

Install Apache Kafka from here.

Step 1: Ensure minimum requirements are met

MinIO requires Kafka version 0.10 or 0.9. Internally MinIO uses the Shopify/sarama library and so has the same version compatibility as provided by this library.

Step 2: Add Kafka endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. Update the kafka configuration block in config.json as follows:

"kafka": {
    "1": {
        "enable": true,
        "brokers": ["localhost:9092"],
        "topic": "bucketevents",
        "queueDir": "",
        "queueLimit": 0,
        "tls": {
            "enable": false,
            "skipVerify": false,
            "clientAuth": 0
        },
        "sasl": {
            "enable": false,
            "username": "",
            "password": ""
        }
    }
}

MinIO supports persistent event store. The persistent store will backup events when the kafka broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the Kafka configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:kafka at start-up if there were no errors.bucketevents is the topic used by kafka in this example.

$ mc admin config set myminio < /tmp/myconfig

Step 3: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded or deleted from images bucket on myminio server. Here ARN value is arn:minio:sqs::1:kafka. To understand more about ARN please follow AWS ARN documentation.

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:kafka --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:kafka s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 4: Test on Kafka

We used kafkacat to print all notifications on the console.

kafkacat -C -b localhost:9092 -t bucketevents

Open another terminal and upload a JPEG image into images bucket.

mc cp myphoto.jpg myminio/images

kafkacat prints the event notification to the console.

kafkacat -b localhost:9092 -t bucketevents
{"EventType":"s3:ObjectCreated:Put","Key":"images/myphoto.jpg","Records":[{"eventVersion":"2.0","eventSource":"aws:s3","awsRegion":"","eventTime":"2017-01-31T10:01:51Z","eventName":"s3:ObjectCreated:Put","userIdentity":{"principalId":"88QR09S7IOT4X1IBAQ9B"},"requestParameters":{"sourceIPAddress":"192.173.5.2:57904"},"responseElements":{"x-amz-request-id":"149ED2FD25589220","x-minio-origin-endpoint":"http://192.173.5.2:9000"},"s3":{"s3SchemaVersion":"1.0","configurationId":"Config","bucket":{"name":"images","ownerIdentity":{"principalId":"88QR09S7IOT4X1IBAQ9B"},"arn":"arn:aws:s3:::images"},"object":{"key":"myphoto.jpg","size":541596,"eTag":"04451d05b4faf4d62f3d538156115e2a","sequencer":"149ED2FD25589220"}}}],"level":"info","msg":"","time":"2017-01-31T15:31:51+05:30"}

Publish MinIO events via Webhooks

Webhooks are a way to receive information when it happens, rather than continually polling for that data.

Step 1: Add Webhook endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. Update the Webhook configuration block in config.json as follows

"webhook": {
  "1": {
    "enable": true,
    "endpoint": "http://localhost:3000/",
    "queueDir": "",
    "queueLimit": 0
}

MinIO supports persistent event store. The persistent store will backup events when the webhook goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in queueDir field and the maximum limit of events in the queueDir in queueLimit field. For eg, the queueDir can be /home/events and queueLimit can be 1000. By default, the queueLimit is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the minio deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the webhook configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Here the endpoint is the server listening for webhook notifications. Save the file and restart the MinIO server for changes to take effect. Note that the endpoint needs to be live and reachable when you restart your MinIO server.

$ mc admin config set myminio < /tmp/myconfig

Step 2: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded to images bucket on myminio server. Here ARN value is arn:minio:sqs::1:webhook. To learn more about ARN please follow AWS ARN documentation.

mc mb myminio/images
mc mb myminio/images-thumbnail
mc event add myminio/images arn:minio:sqs::1:webhook --event put --suffix .jpg

Check if event notification is successfully configured by

mc event list myminio/images

You should get a response like this

arn:minio:sqs::1:webhook   s3:ObjectCreated:*   Filter: suffix=".jpg"

Step 3: Test with Thumbnailer

We used Thumbnailer to listen for MinIO notifications when a new JPEG file is uploaded (HTTP PUT). Triggered by a notification, Thumbnailer uploads a thumbnail of new image to MinIO server. To start with, download and install Thumbnailer.

git clone https://github.com/minio/thumbnailer/
npm install

Then open the Thumbnailer config file at config/webhook.json and add the configuration for your MinIO server and then start Thumbnailer by

NODE_ENV=webhook node thumbnail-webhook.js

Thumbnailer starts running at http://localhost:3000/. Next, configure the MinIO server to send notifications to this URL (as mentioned in step 1) and use mc to set up bucket notifications (as mentioned in step 2). Then upload a JPEG image to MinIO server by

mc cp ~/images.jpg myminio/images
.../images.jpg:  8.31 KB / 8.31 KB ┃▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓┃ 100.00% 59.42 KB/s 0s

Wait a few moments, then check the bucket’s contents with mc ls — you will see a thumbnail appear.

mc ls myminio/images-thumbnail
[2017-02-08 11:39:40 IST]   992B images-thumbnail.jpg

Publish MinIO events to NSQ

Install an NSQ Daemon from here. Or use the following Docker command for starting an nsq daemon:

docker run --rm -p 4150-4151:4150-4151 nsqio/nsq /nsqd

Step 1: Add NSQ endpoint to MinIO

The MinIO server configuration file is stored on the backend in json format. The NSQ configuration is located in the nsq key under the notify top-level key. Create a configuration key-value pair here for your NSQ instance. The key is a name for your NSQ endpoint, and the value is a collection of key-value parameters.

An example configuration for NSQ is shown below:

"nsq": {
    "1": {
        "enable": true,
        "nsqdAddress": "127.0.0.1:4150",
        "topic": "minio",
        "tls": {
            "enable": false,
            "skipVerify": true
        },
        "queueDir": "",
        "queueLimit": 0
    }
}

MinIO supports persistent event store. The persistent store will backup events when the NSQ broker goes offline and replays it when the broker comes back online. The event store can be configured by setting the directory path in `queueDir` field and the maximum limit of events in the queueDir in `queueLimit` field. For eg, the `queueDir` can be `/home/events` and `queueLimit` can be `1000`. By default, the `queueLimit` is set to 10000.

To update the configuration, use mc admin config get command to get the current configuration file for the MinIO deployment in json format, and save it locally.

$ mc admin config get myminio/ > /tmp/myconfig

After updating the NSQ configuration in /tmp/myconfig , use mc admin config set command to update the configuration for the deployment.Restart the MinIO server to put the changes into effect. The server will print a line like SQS ARNs: arn:minio:sqs::1:nsq at start-up if there were no errors.

$ mc admin config set myminio < /tmp/myconfig

Note that, you can add as many NSQ daemon endpoint configurations as needed by providing an identifier (like "1" in the example above) for the NSQ instance and an object of per-server configuration parameters.

Step 2: Enable bucket notification using MinIO client

We will enable bucket event notification to trigger whenever a JPEG image is uploaded or deleted images bucket on myminio server. Here ARN value is arn:minio:sqs::1:nsq.

mc mb myminio/images
mc event add  myminio/images arn:minio:sqs::1:nsq --suffix .jpg
mc event list myminio/images
arn:minio:sqs::1:nsq s3:ObjectCreated:*,s3:ObjectRemoved:* Filter: suffix=”.jpg”

Step 3: Test on NSQ

The simplest test is to download nsq_tail from nsq github

./nsq_tail -nsqd-tcp-address 127.0.0.1:4150 -topic minio

Open another terminal and upload a JPEG image into images bucket.

mc cp gopher.jpg myminio/images

You should receive the following event notification via NSQ once the upload completes.

{"EventName":"s3:ObjectCreated:Put","Key":"images/gopher.jpg","Records":[{"eventVersion":"2.0","eventSource":"minio:s3","awsRegion":"","eventTime":"2018-10-31T09:31:11Z","eventName":"s3:ObjectCreated:Put","userIdentity":{"principalId":"21EJ9HYV110O8NVX2VMS"},"requestParameters":{"sourceIPAddress":"10.1.1.1"},"responseElements":{"x-amz-request-id":"1562A792DAA53426","x-minio-origin-endpoint":"http://10.0.3.1:9000"},"s3":{"s3SchemaVersion":"1.0","configurationId":"Config","bucket":{"name":"images","ownerIdentity":{"principalId":"21EJ9HYV110O8NVX2VMS"},"arn":"arn:aws:s3:::images"},"object":{"key":"gopher.jpg","size":162023,"eTag":"5337769ffa594e742408ad3f30713cd7","contentType":"image/jpeg","userMetadata":{"content-type":"image/jpeg"},"versionId":"1","sequencer":"1562A792DAA53426"}},"source":{"host":"","port":"","userAgent":"MinIO (linux; amd64) minio-go/v6.0.8 mc/DEVELOPMENT.GOGET"}}]}

NOTE If you are running distributed MinIO, modify ~/.minio/config.json on all the nodes with your bucket event notification backend configuration.