Website (Poll)

The Website (Poll) feed type in ArcGIS Analytics for IoT will send an HTTP request to the specified website URL. This will collect any data that could be retrieved in a web browser by simply browsing to the same URL.

Example

  • Updated sensor values are loaded from a website every minute.

Usage notes

  • The feed will poll the website to load data at the rate defined on the Feed Polling Interval step of the configuration wizard.
  • The website must be externally accessible on the Internet.
  • The size of the web page or file being polled should not exceed 8 MB. If the website page or file being polled exceeds 8 MB, features may not be ingested.
  • When a polling interval is set, the polling occurs on regular clock intervals as opposed to the start time of the feed. For example, if a feed is set to poll for data every 5 minutes, and the feed is started at 8:03am, the first request for data will occur at 8:05am, the next at 8:10am, and so on.
  • Use caution when defining the feed polling interval. It is essential to ensure the website being polled is capable of returning responses within the polling interval specified. A recommended best practice is to test the response time of a request to the website, using the same request that you apply in the feed configuration. The polling interval should never be set to a shorter interval than the typical response time of the request to the website. For more information, see Schedule feed polling interval.
  • Both the URL parameters and Custom headers parameters can make use of feed global variables. The feed global variables translate into epoch time (milliseconds since January 1, 1970 UTC). The following outlines the feed analytic variables and what time they represent.
    • $feed.FeedStartTime—Time the feed was started.
    • $feed.FeedScheduledStartTime—Time the next recurrence of the feed is scheduled.
    • $feed.FeedLastScheduledStartTime—Time the last recurrence of the feed was scheduled.

After configuring feed connection properties, see Configure input data to learn how to define the schema and the key properties.

Parameters

ParameterExplanationData Type

URL

The full URL to the externally accessible website.

String

HTTP method

The HTTP method to utilize for the website, either GET or POST.

If POST is selected, optionally specify a message body.

String

POST body

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

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

String

Authentication

The type of authentication to access the web server. Authentication options include None, Basic, and Certificate.

String

Username

The username for accessing the website.

This parameter only applies when Authentication is Basic.

String

Password

The password for accessing the website.

This parameter only applies when Authentication is Basic.

Password

Certificate URL

The URL location of the client certificate for accessing the website.

This parameter only applies when Authentication is 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 sent to the specified website. For example, custom headers can be used to specify a third party API key or authorization header.

Supports feed global variables.

Key-Value Pair

URL parameters

Optional URL parameters to be included in the URL of the HTTP request sent to the specified website.

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

Parameters defined in this property will always be URL encoded.

Supports feed global variables.

Key-Value Pair

Long polling

Analytics for IoT will poll the web server and maintain an open connection, waiting for the server to send new data. When Analytics for IoT receives data it will immediately send a new request.

Note:

This is a unique web server configuration not common to most web servers.

Boolean

Considerations and limitations

  • The website must be externally accessible on the Internet.
  • The size of the web page or file being polled cannot exceed 8 MB.
  • The polling interval should never be set to a shorter interval than the typical response time of the request to the website. For more information, see Schedule feed polling interval.
  • As a best practice, use this feed type for real-time data with velocity of ~3000 point features per second or less. Supported velocity will vary depending upon the number of data attributes, incoming data format, and polyline/polygon feature complexity.