Stream Link

Stream Link task

The Stream Link task assigns unique values to sections of a raster linear network between intersections.

Links are the sections of a stream channel connecting two successive junctions, a junction and the outlet, or a junction and the drainage divide.

The input stream raster can be created by thresholding the results of the Flow Accumulation task.

The stream raster linear network should be represented as values greater than or equal to one on a background of NoData.

Request URL

http://<raster analysis url>/StreamLink/submitJob

Request Parameters

The following table lists the parameters with syntax and details for each.

ParameterDescription

inputStreamRaster

(Required)

The input raster that represents a linear stream network.

Syntax: This parameter can be specified as a Portal Item ID, a URL to a raster image service layer, or a cloud raster dataset.

Examples:

  • "inputStreamRaster": {"itemId": <portal item id>}
  • "inputStreamRaster": {"url": <image service layer url>}

inputFlowDirectionRaster

(Required)

The input raster that shows the direction of flow out of each cell.

Syntax: This parameter can be specified as a Portal Item ID, a URL to a raster image service layer, or a cloud raster dataset.

Examples:

  • "inputFlowDirectionRaster": {"itemId": <portal item id>}
  • "inputFlowDirectionRaster": {"url": <image service layer url>}

outputName

(Required)

The output image service name that will be created.

Syntax: A JSON object describes the name of the output or the output raster.

You can specify the name, or you can create an empty service using Portal Admin Sharing API and use the return JSON object as input to this parameter.

Output name example:

"outputName":{"serviceProperties":{"name":"testrasteranalysis"}}

Output raster examples:

"outputName":{"itemId": <portal item id>}
"outputName":{"url": <image service url}
"outputName":{"serviceProperties":
                  {"name":"testrasteranalysis",
                   "serviceUrl":"http://<server name>/server/rest/services/Hosted/testrasteranalysis/ImageServer"},
                   "itemProperties":{"itemId":"8cfbd3ec25584d0d8f4ed23b8ff7c43b","folderId":"sdfwerfbd3ec25584d0d8f4"}}

context

Contains additional settings that affect task execution.

This task has the following settings:

  • Extent (extent)—A bounding box that defines the analysis area.
  • Output Spatial Reference (outSR)—The output raster will be projected into the output spatial reference.
  • Snap Raster (snapRaster)—The output raster will have its cells aligned with the specified snap raster.
  • Cell Size (cellSize)—The output raster will have the resolution specified by cell size.
  • Mask (mask)—Only cells that fall within the analysis mask will be considered in the operation.

f

The response format. The default response format is html.

Values: html | json

Response

When you submit a request, the task assigns a unique job ID for the transaction.

Syntax:

{
"jobId": "<unique job identifier>",
"jobStatus": "<job status>"
}

After the initial request is submitted, you can use the jobId to periodically check the status of the job and messages as described in Checking job status. Once the job has successfully completed, you use the jobId to retrieve the results. To track the status, you can make a request of the following form:

http://<raster analysis url>/StreamLink/jobs/<jobId>

Accessing results

When the status of the job request is esriJobSucceeded, you can access the results of the analysis by making a request of the following form:

http://<raster analysis url>/jobs/<jobId>/results/outputRaster?token=<your token>&f=json

ParameterDescription

outputRaster

This is the output stream link raster item ID and URL.

Example:

{"url": "http://<raster analysis url>/StreamLink/jobs/<jobId>/results/outputRaster"}

The result has properties for parameter name, data type, and value. The content of value is always the itemid of the output raster dataset and the image service URL. For example:

{
    "paramName": "outRaster",
    "dataType": "GPString",
    "value": {
        "itemId": "f121390b85ef419790479fc75b493efd", 
        "url": "https://<server name>/arcgis/rest/services/Hosted/<service name>/ImageServer"
    }
}