Working with Data Providers

Data providers are the sources from which information is fetched to be displayed in widgets. This section describes how to configure the data providers that are currently supported in WSO2 Stream Processor are as follows. These configurations determine the parameters that are available to be configured for each data provider when creating widgets via the Widget Generation wizard. For more information, see Generating Widgets.

RDBMS Batch Data Provider

This data provider queries static tables. The following configuration is an example of an RDBMS Batch Data Provider:

"config": {
          "datasourceName": "Twitter_Analytics",
          "queryData": {
            "query": "select type as Sentiment, count(TweetID) as Rate from sentiment where PARSEDATETIME(timestamp, 'yyyy-mm-dd hh:mm:ss','en') > CURRENT_TIMESTAMP()-86400 group by type"
          },
          "tableName": "sentiment",
          "incrementalColumn": "Sentiment",
          "publishingInterval": 60
}

RDBMS Streaming Data Provider

This data provider queries dynamic tables. Here, the newer records are published as soon as the table is updated. The following configuration is an example of an RDBMS Streaming Data Provider:

"configs": {
        "type": "RDBMSStreamingDataProvider",
        "config": {
          "datasourceName": "Twitter_Analytics",
          "queryData": {
            "query": "select id,TweetID from sentiment"
          },
          "tableName": "sentiment",
          "incrementalColumn": "id",
          "publishingInterval": 5,
          "publishingLimit": 5,
          "purgingInterval": 6,
          "purgingLimit": 6,
          "isPurgingEnable": false
        }
      }

Siddhi Store Data Provider

This data provider runs a siddhi store query. The following configuration is an example of a Siddhi Store Data Provider:

The Siddhi application included in this query must not contain any source configurations.

"configs":{
                "type":"SiddhiStoreDataProvider",
                "config":{
                    "siddhiApp":"@App:name(\"HTTPAnalytics\") define stream ProcessedRequestsStream(timestamp long, serverName string, serviceName string, serviceMethod string, responseTime double, httpRespGroup string, userAgent string, requestIP string); define aggregation RequestAggregation from ProcessedRequestsStream select serverName, serviceName, serviceMethod, httpRespGroup, count() as numRequests, avg(responseTime) as avgRespTime group by serverName, serviceName, serviceMethod, httpRespGroup aggregate by timestamp every sec...year;",
                    "queryData":{
                        "query":"from RequestAggregation within \"2018-**-** **:**:**\" per \"days\" select AGG_TIMESTAMP, serverName, avg(avgRespTime) as avgRespTime"
                    },
                    "publishingInterval":60
                }
            }

Web Socket Provider

This data provider utilizes web siddhi-io-web socket sink to provide data to the clients. It creates endpoints as follows for the web socket sinks to connect and publish information.

  wss://host:port/websocket-provider/{topic}

The host and port will be the host and port of the Portal Web application

The following configuration is an example of a web socket data provider.

{
    configs: {
        type: 'WebSocketProvider', 
        config: {
            subscriberTopic: 'sampleStream', 
            mapType: 'json' 
        }
    }
}