HTTP Poller

The HTTP Poller data source in ArcGIS Velocity sends an HTTP request to the specified URL. This ingests data that can be retrieved in a web browser by browsing to the same URL.

Example

A GIS analyst wants to load district polygons stored in a .csv file on a web server into Velocity.

Usage notes

  • The HTTP endpoint must be externally accessible on the internet.
  • The size of the HTTP response or file being polled cannot exceed 16 MB. If the data or file being polled exceeds 16 MB, features will not be ingested.
  • After configuring source connection parameters, configure the input data to define the schema and the key parameters.
  • Both the URL parameters and Custom headers parameters can use analytic global variables for scheduling recurring big data analysis. When analytics run, these global variables are converted into epoch time (milliseconds since January 1, 1970 UTC). The following outlines the available analytic variables and the time they represent.
    • $analytic.AnalyticLastScheduledStartTime—The time the last run of the analytic was scheduled to start
    • $analytic.AnalyticScheduledStartTime—The time the current run of the analytic was scheduled to start
    • $analytic.AnalyticLastEndTime—The time the last run of the analytic ended
    • $analytic.AnalyticStartTime—The time the current run of the analytic started (the difference between this and $analytic.AnalyticScheduledStartTime is the startup delay).

Parameters

ParameterDescriptionData type

URL

The full URL to the externally accessible HTTP endpoint.

String

HTTP method

The HTTP method used for the HTTP endpoint, either GET or POST.

If POST is chosen, you can specify a message body.

String

POST body

The message body to be included when sending a POST HTTP request.

This provides a selection between x-www-form-urlencoded and other generic text content types. It also sets the Content-type header.

This parameter only applies when HTTP Method is set to POST.

String

Authentication

The type of authentication used to access the HTTP endpoint. Authentication options are None, Basic, and Certificate.

String

Username

The user name for accessing the HTTP endpoint.

This parameter only applies when Authentication is set to Basic.

String

Password

The password for accessing the HTTP endpoint.

This property only applies when Authentication is set to Basic.

Password

Certificate URL

The URL location of the client certificate for accessing the HTTP endpoint.

This parameter only applies when Authentication is set to Certificate.

String

Password

The client certificate password if one is set.

This parameter only applies when Authentication is set to Certificate.

Password

Custom headers

Optional custom headers to be included in the HTTP request that is sent to the specified HTTP endpoint.

For example, custom headers can be used to specify a third-party API key or authorization header.

This parameter supports analytic global variables.

Key-Value Pair

URL parameters

Optional URL parameters to be included in the URL of the HTTP request that is sent to the specified HTTP endpoint.

While parameters can also be set in the URL parameter, the URL parameters entered here as a separate property will override any matching parameter supplied for the URL parameter.

Parameters defined here will always be URL encoded.

This parameter supports analytic global variables.

Key-Value Pair

Considerations and limitations

The HTTP endpoint must be externally accessible on the internet.