# Pub/Sub

Kubemq gcp-pubsub target connector allows services using kubemq server to access google pubsub server.

## Prerequisites

The following required to run the gcp-pubsub target connector:

* kubemq cluster
* gcp-pubsub set up
* kubemq-source deployment

## Configuration

pubsub target connector configuration properties:

| Properties Key | Required | Description               | Example                     |
| -------------- | -------- | ------------------------- | --------------------------- |
| project\_id    | yes      | gcp firestore project\_id | "/myproject"                |
| credentials    | yes      | gcp credentials files     | "\<google json credentials" |
| retries        | no       | number of sending retires | retries number              |

Example:

```yaml
bindings:
  - name: kubemq-query-gcp-pubsub
    source:
      kind: kubemq.query
      name: kubemq-query
      properties:
        address: "kubemq-cluster:50000"
        client_id: "kubemq-query-gcp-pubsub-connector"
        auth_token: ""
        channel: "query.gcp.pubsub"
        group:   ""
        auto_reconnect: "true"
        reconnect_interval_seconds: "1"
        max_reconnects: "0"
    target:
      kind: gcp.pubsub
      name: gcp-pubsub
      properties:
        project_id: "projectID"
        retries:    "0"
        credentials: 'json'
```

## Usage

### Send Message

send a message to pub sub

Send Message metadata setting:

| Metadata Key | Required | Description                        | Possible values  |
| ------------ | -------- | ---------------------------------- | ---------------- |
| topicID      | yes      | the name of the topicID to sent to | valid topicID    |
| tags         | no       | type of method                     | key value string |

Example with tags:

```javascript
{
  "metadata": {
    "topic_id": "my_topic",
    "tags": "{\"tag-1\":\"test\",\"tag-2\":\"test2\"}"
  },
  "data": "c3RyaW5n"
}
```

Example without tags:

```javascript
{
  "metadata": {
    "topic_id": "my_topic"
  },
  "data": "c3RyaW5n"
}
```