Revision as of 17:56, 20 May 2019

Aim of this service is to describe the implementation of gFeed-Service (for more information refer to GFeed).

Architecture

Deployment

Plugins

Plugins are expected to be found in the service classpath. They are typically distributed as uber-jar and their deployment depends on the hosting container.

To see a complete list of available plugins implemetations please refer to gFeed-Plugins

IS Requirements

The following is a list of minimal requirements for the execution of gFeed Service. Please keep in mind that depending on deployed plugins these requirements may not be enough.

• Database : the service needs a dedicated DB for its logic and looks in the current context for a DB registered as Service Endpoint with
  • Category : Database
  • Name : Feeder_DB

• Common configuration : the service loads default plugins configurations from the IS by lookig for a Generic Resource registered as
  • Secondary type : configuration
  • Name : gcat-feeder

HTTP Interface

Following is a list of methods exposed by gFeed HTTP interface. All methods require authentication so keep in mind that a gcube-token is expected. In this section <BASE_URL> stands for http(s)://<HOSTNODE>/gCat-Feeder/gcube/service/ where <HOSTNODE> should be determined by querying the gCube Information System.

Capabilities

Get available collectors

In order to get information on available collectors clients can perform a GET HTTP method on <BASE_URL>/capabilities/collectors. The response is a JSON representation of available collectors.

Get available controllers

In order to get information on available controllers clients can perform a GET HTTP method on <BASE_URL>/capabilities/controllers. The response is a JSON representation of available controllers.

Executions

Submission

In order to submit an execution clients can perform a POST HTTP method on <BASE_URL>/execution. Following parameters are expected to be declared in the query string (multiple values can be specified):

• Parameter collector
  • expected value : to invoke collector ID
  • default value ALL

• Parameter controller
  • expected value : to invoke controller ID
  • default value ALL

The resulting execution will be the combination of all requested collectors publishing their data to all requested controllers (only implemented transformation will be performed).

Available plugins ID can be retrieved by invoking related #Capabilities methods.

The resulting response is the ID of the submitted execution.

Examples

Following is a list of typical usages :

• Perform all available combinations : <BASE_URL>/execution
• Collect DataMiner Algorihtms information and push them in gCat service : <BASE_URL>/execution?collector=DATAMINER_ALGORITHMS_COLLECTOR&controller=GCAT

Get submission history

In order to get the history of submitted executions clients can perform a GET HTTP method on <BASE_URL>/execution. The response is a JSON array of reports referring to submitted executions.

Get report

In order to get a report for a specific execution clients can perform a GET HTTP method on <BASE_URL>/execution/<EXECUTION_ID>, where <EXECUTUION_ID> is the id returned from submission method. Aim of this method is to monitor the outcome of a submitted execution (Asynch logic).

Please keep in mind that detailed reports are provided as a text file, accessible at reportUrl. The following is a report example :

 {
    "id": 4,
    "collectors": [
      "DATAMINER_ALGORITHMS_COLLECTOR"
    ],
    "catalogues": [
      "GCAT"
    ],
    "callerEncryptedToken": ...,
    "callerIdentity": ...,
    "callerContext": ...,
    "status": "SUCCESS",
    "reportUrl": ...,
    "startTime": ...,
    "endTime": ...
  }