How it works

Introduction

Notifier responsibilities:

• Manage rules and recipients configuration,
• Send notifications to external users or components according to its configuration.

The service only has one module. This one receives the notifications, mainly from GeoJSON and OAIS catalogs. Then, these notifications pass through rules and, if they match the rules, jobs are launched to send notification thanks to various plugins.

Configuration is an important part of this service, as the rules and the plugins are defined through the Notifier service configuration.

At the moment, 2 API are available:

• A REST API to manage configuration
• A messaging API (AMQP) for the receipt of the requests to be processed

This microservice receives requests from Feature manager and Ingest.

All requests are then processed as they arrive:

• All rules are applied to all requests in order to identify target recipients
• Notifications are then sent to these recipients

Under the hood, all the real work is done by the plugins.

Notification format

The notifier microservice allows you to forward any type of notification with any type of content, as long as you comply with the specific format indicated below.

{
  "metadata": {},
  "payload": {}
}

Section	Type	Description	Mandatory
Metadata	Object	Set of metadata describing the notification (can be empty)	True
Payload	Object	Content of the notification to be distributed.	True

For example, you can find the format of the notifications sent by the FeatureManager and Ingest microservices as part of the respective functional groups GeoJson catalog services and OAIS Catalog services in the documentation for each of the two services:

• [Products notification format sent by Feature manager service]
• Products notification format sent by Ingest service

Configure recipients

The first thing to do when configuring the rs-notifier microservice is to define the recipients to whom notifications will be sent. To do this, you need to ask yourself:

• Which component do I want to notify?
• What notification format does the component expect?
• Is there a plugin available for this type of notification?
• Will the recipient acknowledge receipt of the notification?
• Do I authorise the system administrators to manually notify this recipient?

REGARDS provides plugins to :

• broadcast notifications without modification on a RabbitMQ message bus
• broadcast notifications to internal components such as WorkerManager or LTAManager

To learn more on plugins and configuration see recipient plugins section and configuration section.

Example

Let's say we want to send notifications to a recipient named external-system-1 via a RabbitMQ message bus without modifying the content.

Question: Which component do I want to notify?
Response: external-system-1

Question: What notification format does the component expect?
Response: An event sent to Regards RabbitMQ server on a dedicated exchange named external.system-1.dissemination

Question: Is there a plugin available for this type of notification?
Response: Yes, the RabbitMQSender

Question: Will the recipient acknowledge receipt of the notification?
Response: No, my external system is unable to acknowledge.

Question:Do I authorise the system administrators to manually notify this recipient?
Response:Yes

{
  "key": "fr.cnes.regards.framework.modules.plugins.domain.PluginConfiguration",
  "value": {
    "pluginId": "RabbitMQSender",
    "label": "External system one",
    "businessId": "external-system-1",
    "version": "1.0.0",
    "priorityOrder": 0,
    "active": true,
    "parameters": [
      {
        "name": "exchange",
        "type": "STRING",
        "value": "external.system-1.dissemination"
      },
      {
        "name": "queueName",
        "type": "STRING",
        "value": "external.system-1.dissemination"
      },
      {
        "name": "recipientLabel",
        "type": "STRING",
        "value": "external-system-1"
      },
      {
        "name": "ackRequired",
        "type": "BOOLEAN",
        "value": false
      },
      {
        "name": "description",
        "type": "STRING",
        "value": "Send notification to external-system-1"
      },
      {
        "name": "directNotificationEnabled",
        "type": "BOOLEAN",
        "value": true
      }
    ]
  }
}

Configure dispatching rules

After determining who will receive the notifications sent by the Notify microservice, you then need to determine the rules for selecting the notifications that will be broadcast.

To do this, you need to ask yourself:

• Which notifications do I want to forward to my recipient?
• Is there a rules plugin that allows me to select these notifications?

REGARDS provides two rule plugins lucene and default.

To learn more on plugins and configuration see rules plugins section and configuration section.

GeoJson Product rule configuration example

For example, let's imagine that we want to send to recipients all GeoJson product notifications indicating the creation of a new product and whose is_valid property is equal to true.

Question: Which notifications do I want to forward to my recipient?
Response : GeoJson (or rs-fem) product notification. Format of these notifications is defined in the Feature Manager documentation.

Question: Is there a rules plugin that allows me to select these notifications?
Response : Yes, the lucene plugin allows me to make a selection rule in the metadata section for the type of notification indicating the creation of a new product and in the payload section to only notify products with the is_valid attribute set to true.

Notifier rule configuration example

{
  "key": "fr.cnes.regards.framework.modules.plugins.domain.PluginConfiguration",
  "value": {
    "pluginId": "LuceneRuleMatcher",
    "label": "FEM new created valid products rule",
    "businessId": "fem-valid-products-rule",
    "version": "1.0.0",
    "priorityOrder": 0,
    "active": true,
    "parameters": [
      {
        "name": "payload_rule",
        "type": "STRING",
        "value": "properties.is_valid: true"
      },
      {
        "name": "metadata_rule",
        "type": "STRING",
        "value": "action: CREATED"
      }
    ]
  }
}

OAIS Product rule configuration example

For example, let's imagine that we want to send to recipients all OAIS product notifications indicating the creation of a new product and whose is_valid property is equal to true.

Question: Which notifications do I want to forward to my recipient ?
Response : OAIS product notification. Format of these notifications is defined in the ingest documentation.

Question: Is there a rules plugin that allows me to select these notifications?
Response : Yes, the lucene plugin allows me to make a selection rule in the metadata section for the type of notification indicating the creation of a new product and in the payload section to only notify products with the is_valid attribute set to true.

Notifier rule configuration example

{
  "key": "fr.cnes.regards.framework.modules.plugins.domain.PluginConfiguration",
  "value": {
    "pluginId": "LuceneRuleMatcher",
    "label": "OAIS new created valid products rule",
    "businessId": "oais-valid-products-rule",
    "version": "1.0.0",
    "priorityOrder": 0,
    "active": true,
    "parameters": [
      {
        "name": "payload_rule",
        "type": "STRING",
        "value": "aip.properties.descriptiveInformation.is_valid: true"
      },
      {
        "name": "metadata_rule",
        "type": "STRING",
        "value": "action: INGEST"
      }
    ]
  }
}

Associate rules and recipients

The last thing to do to configure the Notifier microservice is to associate the broadcast rules with the recipients. This means that any notification that respects a configured rule will be broadcast to one or more configured recipients.

To lean more on how to configure the service see configuration section.

Example

Let's say I want to associate the rule in the example for distributing new valid OAIS products with the external-system-1 recipient presented in the previous examples.

Notifier configuration example

{
  "key": "fr.cnes.regards.modules.notifier.dto.conf.RuleRecipientsAssociation",
  "value": {
    "ruleId": "oais-valid-products-rule",
    "recipientIds": [
      "external-system-1"
    ]
  }
}