Nodes, parameters, and services¶
Nodes represent the rc_visard NG’s software modules , each bundling a certain algorithmic functionality. All available global REST-API database nodes can be listed with their service calls and parameters using
curl -X GET http://<host>/api/v2/nodes
Information about a specific node (e.g., rc_load_carrier_db
) can be retrieved using
curl -X GET http://<host>/api/v2/nodes/rc_load_carrier_db
All available 3D camera, detection and configuration REST-API nodes can be listed with their service calls and parameters using
curl -X GET http://<host>/api/v2/pipelines/0/nodes
Information about a specific node (e.g., rc_camera
) can be retrieved using
curl -X GET http://<host>/api/v2/pipelines/0/nodes/rc_camera
- Status:
During run-time, each node offers information about its current status. This includes not only the current processing status of the module (e.g.,
running
orstale
), but most nodes also offer run-time statistics or read-only parameters, so-called status values. As an example, therc_camera
values can be retrieved usingcurl -X GET http://<host>/api/v2/pipelines/0/nodes/rc_camera/status
Note
The returned status values are specific to individual nodes and are documented in the respective software module .
Note
The status values are only reported when the respective node is in the
running
state.
- Parameters:
Most nodes expose parameters via the rc_visard NG’s REST-API to allow their run-time behaviors to be changed according to application context or requirements. The REST-API permits to read and write a parameter’s value, but also provides further information such as minimum, maximum, and default values.
As an example, the
rc_stereomatching
parameters can be retrieved usingcurl -X GET http://<host>/api/v2/pipelines/0/nodes/rc_stereomatching/parameters
Its
quality
parameter could be set toFull
usingcurl -X PUT http://<host>/api/v2/pipelines/0/nodes/rc_stereomatching/parameters?quality=Full
or equivalently
curl -X PUT --header 'Content-Type: application/json' -d '{ "value": "Full" }' http://<host>/api/v2/pipelines/0/nodes/rc_stereomatching/parameters/quality
Note
Run-time parameters are specific to individual nodes and are documented in the respective software module .
Note
Most of the parameters that nodes offer via the REST-API can be explored and tested via the rc_visard NG’s user-friendly Web GUI .
Note
Some parameters exposed via the rc_visard NG’s REST-API are also available from the GigE Vision 2.0/GenICam image interface . Please note that setting those parameters via the REST-API or Web GUI is prohibited if a GenICam client is connected.
In addition, each node that offers run-time parameters also features a service to restore the default values for all of its parameters.
- Services:
Some nodes also offer services that can be called via REST-API, e.g., to restore parameters as discussed above, or to start and stop nodes. As an example, the services of the hand-eye calibration module could be listed using
curl -X GET http://<host>/api/v2/pipelines/0/nodes/rc_hand_eye_calibration/services
A node’s service is called by issuing a
PUT
request for the respective resource and providing the service-specific arguments (see the"args"
field of the Service data model). As an example, the stereo matching module can be triggered to do an acquisition by:curl -X PUT --header 'Content-Type: application/json' -d '{ "args": {} }' http://<host>/api/v2/pipelines/0/nodes/rc_stereomatching/services/acquisition_trigger
Note
The services and corresponding argument data models are specific to individual nodes and are documented in the respective software module .
The following list includes all REST-API requests regarding the global database nodes’ status, parameters, and services calls:
-
GET
/nodes
¶ Get list of all available global nodes.
Template request
GET /api/v2/nodes HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json [ { "name": "rc_roi_db", "parameters": [], "services": [ "set_region_of_interest", "get_regions_of_interest", "delete_regions_of_interest", "set_region_of_interest_2d", "get_regions_of_interest_2d", "delete_regions_of_interest_2d" ], "status": "running" }, { "name": "rc_load_carrier_db", "parameters": [], "services": [ "set_load_carrier", "get_load_carriers", "delete_load_carriers" ], "status": "running" }, { "name": "rc_gripper_db", "parameters": [], "services": [ "set_gripper", "get_grippers", "delete_grippers" ], "status": "running" } ]
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of NodeInfo)
Referenced Data Models:
-
GET
/nodes/{node}
¶ Get info on a single global node.
Template request
GET /api/v2/nodes/<node> HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "name": "rc_roi_db", "parameters": [], "services": [ "set_region_of_interest", "get_regions_of_interest", "delete_regions_of_interest", "set_region_of_interest_2d", "get_regions_of_interest_2d", "delete_regions_of_interest_2d" ], "status": "running" }
Parameters: - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns NodeInfo)
- 404 Not Found – node not found
Referenced Data Models:
-
GET
/nodes/{node}/services
¶ Get descriptions of all services a global node offers.
Template request
GET /api/v2/nodes/<node>/services HTTP/1.1
Template response
HTTP/1.1 200 OK Content-Type: application/json [ { "args": {}, "description": "string", "name": "string", "response": {} } ]
Parameters: - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of Service)
- 404 Not Found – node not found
Referenced Data Models:
-
GET
/nodes/{node}/services/{service}
¶ Get description of a global node’s specific service.
Template request
GET /api/v2/nodes/<node>/services/<service> HTTP/1.1
Template response
HTTP/1.1 200 OK Content-Type: application/json { "args": {}, "description": "string", "name": "string", "response": {} }
Parameters: - node (string) – name of the node (required)
- service (string) – name of the service (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns Service)
- 404 Not Found – node or service not found
Referenced Data Models:
-
PUT
/nodes/{node}/services/{service}
¶ Call a service of a node. The required args and resulting response depend on the specific node and service.
Template request
PUT /api/v2/nodes/<node>/services/<service> HTTP/1.1 Accept: application/json { "args": {} }
Template response
HTTP/1.1 200 OK Content-Type: application/json { "args": {}, "description": "string", "name": "string", "response": {} }
Parameters: - node (string) – name of the node (required)
- service (string) – name of the service (required)
Request JSON Object: - service args (Service) – example args (required)
Request Headers: - Accept – application/json
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – Service call completed (returns Service)
- 403 Forbidden – Service call forbidden, e.g. because there is no valid license for this module.
- 404 Not Found – node or service not found
Referenced Data Models:
-
GET
/nodes/{node}/status
¶ Get status of a global node.
Template request
GET /api/v2/nodes/<node>/status HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "status": "running", "timestamp": 1503075030.2335997, "values": [] }
Parameters: - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns NodeStatus)
- 404 Not Found – node not found
Referenced Data Models:
The following list includes all REST-API requests regarding the 3D camera, detection and configuration nodes’ status, parameters, and services calls:
-
GET
/pipelines/{pipeline}/nodes
¶ Get list of all available nodes.
Template request
GET /api/v2/pipelines/<pipeline>/nodes HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json [ { "name": "rc_camera", "parameters": [ "fps", "exp_auto", "exp_value", "exp_max" ], "services": [ "reset_defaults" ], "status": "running" }, { "name": "rc_hand_eye_calibration", "parameters": [ "grid_width", "grid_height", "robot_mounted" ], "services": [ "reset_defaults", "set_pose", "reset", "save", "calibrate", "get_calibration" ], "status": "idle" }, { "name": "rc_stereomatching", "parameters": [ "quality", "seg", "fill", "minconf", "mindepth", "maxdepth", "maxdeptherr" ], "services": [ "reset_defaults" ], "status": "running" } ]
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of NodeInfo)
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}
¶ Get info on a single node.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node> HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "name": "rc_camera", "parameters": [ "fps", "exp_auto", "exp_value", "exp_max" ], "services": [ "reset_defaults" ], "status": "running" }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns NodeInfo)
- 404 Not Found – node not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}/parameters
¶ Get parameters of a node.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node>/parameters?name=<name> HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json [ { "default": 25, "description": "Frames per second in Hz", "max": 25, "min": 1, "name": "fps", "type": "float64", "value": 25 }, { "default": true, "description": "Switching between auto and manual exposure", "max": true, "min": false, "name": "exp_auto", "type": "bool", "value": true }, { "default": 0.007, "description": "Maximum exposure time in s if exp_auto is true", "max": 0.018, "min": 6.6e-05, "name": "exp_max", "type": "float64", "value": 0.007 } ]
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
Query Parameters: - name (string) – limit result to parameters with name (optional)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of Parameter)
- 404 Not Found – node not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
PUT
/pipelines/{pipeline}/nodes/{node}/parameters
¶ Update multiple parameters.
Template request
PUT /api/v2/pipelines/<pipeline>/nodes/<node>/parameters HTTP/1.1 Accept: application/json [ { "name": "string", "value": {} } ]
Sample response
HTTP/1.1 200 OK Content-Type: application/json [ { "default": 25, "description": "Frames per second in Hz", "max": 25, "min": 1, "name": "fps", "type": "float64", "value": 10 }, { "default": true, "description": "Switching between auto and manual exposure", "max": true, "min": false, "name": "exp_auto", "type": "bool", "value": false }, { "default": 0.005, "description": "Manual exposure time in s if exp_auto is false", "max": 0.018, "min": 6.6e-05, "name": "exp_value", "type": "float64", "value": 0.005 } ]
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
Request JSON Array of Objects: - parameters (ParameterNameValue) – array of parameters (required)
Request Headers: - Accept – application/json
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of Parameter)
- 400 Bad Request – invalid parameter value
- 403 Forbidden – Parameter update forbidden, e.g. because they are locked by a running GigE Vision application or there is no valid license for this module.
- 404 Not Found – node not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}/parameters/{param}
¶ Get a specific parameter of a node.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node>/parameters/<param> HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "default": 25, "description": "Frames per second in Hertz", "max": 25, "min": 1, "name": "fps", "type": "float64", "value": 10 }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
- param (string) – name of the parameter (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns Parameter)
- 404 Not Found – node or parameter not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
PUT
/pipelines/{pipeline}/nodes/{node}/parameters/{param}
¶ Update a specific parameter of a node.
Template request
PUT /api/v2/pipelines/<pipeline>/nodes/<node>/parameters/<param> HTTP/1.1 Accept: application/json { "value": {} }
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "default": 25, "description": "Frames per second in Hertz", "max": 25, "min": 1, "name": "fps", "type": "float64", "value": 10 }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
- param (string) – name of the parameter (required)
Request JSON Object: - parameter (ParameterValue) – parameter to be updated as JSON object (required)
Request Headers: - Accept – application/json
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns Parameter)
- 400 Bad Request – invalid parameter value
- 403 Forbidden – Parameter update forbidden, e.g. because they are locked by a running GigE Vision application or there is no valid license for this module.
- 404 Not Found – node or parameter not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}/services
¶ Get descriptions of all services a node offers.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node>/services HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json [ { "args": {}, "description": "Restarts the module.", "name": "restart", "response": { "accepted": "bool", "current_state": "string" } }, { "args": {}, "description": "Starts the module.", "name": "start", "response": { "accepted": "bool", "current_state": "string" } }, { "args": {}, "description": "Stops the module.", "name": "stop", "response": { "accepted": "bool", "current_state": "string" } } ]
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns array of Service)
- 404 Not Found – node not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}/services/{service}
¶ Get description of a node’s specific service.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node>/services/<service> HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "args": { "pose": { "orientation": { "w": "float64", "x": "float64", "y": "float64", "z": "float64" }, "position": { "x": "float64", "y": "float64", "z": "float64" } }, "slot": "int32" }, "description": "Save a pose (grid or gripper) for later calibration.", "name": "set_pose", "response": { "message": "string", "status": "int32", "success": "bool" } }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
- service (string) – name of the service (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns Service)
- 404 Not Found – node or service not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
PUT
/pipelines/{pipeline}/nodes/{node}/services/{service}
¶ Call a service of a node. The required args and resulting response depend on the specific node and service.
Template request
PUT /api/v2/pipelines/<pipeline>/nodes/<node>/services/<service> HTTP/1.1 Accept: application/json { "args": {} }
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "name": "set_pose", "response": { "message": "Grid detected, pose stored.", "status": 1, "success": true } }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
- service (string) – name of the service (required)
Request JSON Object: - service args (Service) – example args (required)
Request Headers: - Accept – application/json
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – Service call completed (returns Service)
- 403 Forbidden – Service call forbidden, e.g. because there is no valid license for this module.
- 404 Not Found – node or service not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of
-
GET
/pipelines/{pipeline}/nodes/{node}/status
¶ Get status of a node.
Template request
GET /api/v2/pipelines/<pipeline>/nodes/<node>/status HTTP/1.1
Sample response
HTTP/1.1 200 OK Content-Type: application/json { "status": "running", "timestamp": 1503075030.2335997, "values": { "baseline": "0.0650542", "color": "0", "exp": "0.00426667", "focal": "0.844893", "fps": "25.1352", "gain": "12.0412", "height": "960", "temp_left": "39.6", "temp_right": "38.2", "time": "0.00406513", "width": "1280" } }
Parameters: - pipeline (string) – name of the pipeline (one of
0
) (required) - node (string) – name of the node (required)
Response Headers: - Content-Type – application/json
Status Codes: - 200 OK – successful operation (returns NodeStatus)
- 404 Not Found – node not found
Referenced Data Models: - pipeline (string) – name of the pipeline (one of