Interaction with backend server¶

Client application can connect to WCS OAM backend server to receive metrics data and to manage data aquisition by two ways:

using Websocket API
using REST API

Interaction using Websocket API¶

To get WCS stream information in realtime and to manage WCS monitoring, STOMP based Websocket API can be used

Connecting to backend server via STOMP over Websocket¶

To connect to backend server, do the following:

Establish Secure Websocket connection to https://hostname:8090/ws, where hostname is backend server host name

Establish STOMP connection by sending the message

CONNECT
accept-version:1.2
host:hostname

^@

Subscribe to /alarms queue for alarms receiving by sending the message
```
SUBSCRIBE
id:sub-0
destination:/alarm

^@
```
Subscribe to /user/service queue to receive responses to requests by sending the message
```
SUBSCRIBE
id:sub-1
destination:/user/service

^@
```

Requests sending and responses receiving¶

Requests should be sent as STOMP messages, for example

SEND
destination:/app/api/metric/list
content-length:100

{"requestId":"eb2c2807-8c2f-4418-aebe-03622404e4bb","realm":"/api/metric/list","payload":{"id":"3"}}^@

Where:

destination - reqiuest URI
content-length - request body length

Request body is JSON object with te following parameters:

requestId - unique request identifier
realm - request method used
payload - request data depending on method used

Response will be received asynchronously in /user/service queue as STOMP message, for example

MESSAGE
destination:/user/service
content-type:application/json;charset=UTF-8
subscription:sub-1
message-id:3-8
content-length:159

{"requestId":"eb2c2807-8c2f-4418-aebe-03622404e4bb","status":200,"reason":"SUCCESS","payload":[{"id":3,"name":"Video rate","note":"","enumName":"VIDEO_RATE"}]}^@

Where:

destination - queue URI
content-type - content type (always application/json)
subscription - subscription identifier
message-id - message identifier
content-length - response body length

Response body is JSON object with te following parameters:

requestId - unique request identifier
status - standard HTTP response status
reason - response reason phrase
payload - response data depending on request data and response status

Interaction using REST API¶

To receive WCS stream information and to manage WCS monitoring, REST API can be used

REST query should be HTTPS POST request as follows:

https://wcsoam.flashphoner.com:8090/api/stream/history

Здесь:

wcsoam.flashphoner.com - backend server address
8090 - HTTPS port
/api/stream/history - REST method used

Connection setup¶

Port configuration¶

HTTPS port to handle REST queries and WSS connections can be set with the following parameter in wcsoam.properties file

server.port = 8090

Websocket connection timeout configuration¶

Websocket connection timeout is set with the following parameter in wcsoam.properties file

stomp_max_timeout=1000

CORS configuration¶

Cross-domain requests should be allowed to establish connection from browser with the following parameter in wcsoam.properties file

access_control_allow_origin=*