Poll an ArcGIS Server for Features

The Poll an ArcGIS Server for Features Input Connector can be used to poll an ArcGIS Enterprise or ArcGIS Online map/feature service layer for feature records in order to process them as event records.

Usage notes

• Use this input connector to retrieve features from a map or feature service layer.
• This input connector pairs the Feature JSON Inbound Adapter with the Feature Service Inbound Transport. The Feature JSON Inbound Adapter specifically interprets feature JSON. For more information, see Geometry objects.
• ArcGIS Enterprise, ArcGIS Online, and ArcGIS Server (stand-alone) map and feature services are supported.
• Like all input connectors, a GeoEvent Definition is required. A GeoEvent Definition identifies the schema of event records being received. For more information, see Managing GeoEvent Definitions.
• Data values from event attribute fields not included in a GeoEvent Definition are ignored.
• This input connector periodically polls a specified map/feature layer at a specified interval. As with any web server or web service, excessive polling intervals, for example every second, is not recommended.
• A simple WHERE clause is used to identify the feature record set returned with each poll of the map/feature service. The default is to include all records in the polled feature record set, for example WHERE 1=1. The default WHERE clause can be modified to include specific attribute values and logic conditions.
• Supports spatial filters which use a specified geometry and spatial relationship, for example polygon intersects.
• Supports a unique capability to poll for newly added or updated feature records using Get Incremental Updates.
• Get Incremental Updates uses ObjectID or Timestamp values, retrieved from feature records, and cached by the input connector.
• The cached attribute value is incorporated into the connector's WHERE clause to query for records greater-than the cached value. For more information, see the GeoNet blog Polling Feature Services for Incremental Updates.
• Supports the optional deletion of polled records from the map/feature layer being polled.

Parameters

Parameter	Description
Name	A descriptive name for the input connector used for reference in GeoEvent Manager.
ArcGIS Server Connection	An ArcGIS Server, ArcGIS Enterprise, or ArcGIS Online connection registered with ArcGIS GeoEvent Server as a data store. Registered server connections cache information about map/feature services, their layers, and layer properties.
Folder	An ArcGIS Server services folder or Enterprise portal/ArcGIS Online content item folder.
Service Name	The name of the map/feature service from which you want to poll feature records.
Layer	The map/feature service feature layer through which feature records are accessed.
Create GeoEvent Definition	Specifies whether a new or existing GeoEvent Definition should be used for the inbound event data. A GeoEvent Definition is required for GeoEvent Server to understand the inbound event data attribute fields and data types. Yes – A new GeoEvent Definition will be created based on the schema of the first event record received. No – A new GeoEvent Definition will not be created. Select an existing GeoEvent Definition that matches the schema of the inbound event data.
GeoEvent Definition Name (New) (Conditional)	The name assigned to a new GeoEvent Definition. If a GeoEvent Definition with the specified name already exists, the existing GeoEvent Definition will be used. The first data record received will be used to determine the expected schema of subsequent data records, a new GeoEvent Definition will be created based on that first data record's schema. Property is shown when Create GeoEvent Definition is set to Yes and is hidden when set to No.
GeoEvent Definition Name (Existing) (Conditional)	The name of an existing GeoEvent Definition to use when adapting received data to create event data for processing by a GeoEvent Service. Property is shown when Create GeoEvent Definition is set to No and is hidden when set to Yes.
Refresh Interval	The period (in seconds) in which a map/feature service feature layer will be polled for feature records. The default is 10 (one poll request will be sent every 10 seconds).
Get Incremental Updates	Specifies whether to request only new or updated feature records using a cached ObjectID or Timestamp value. The default value is No. Yes - GeoEvent Server will poll for incremental updates using either a cached ObjectID or Timestamp. No - GeoEvent Server will not incorporate a cached ObjectID or Timestamp in its feature record polls. Nota: If an input connector is deleted and recreated, the ArcGIS GeoEvent Server service is stopped or restarted, or the server machine is restarted, the cached key value will be lost. A new key value will be cached once available feature records are polled and the feature record set returned from the map/feature service is examined.
Method to Identify Incremental Updates (Conditional)	Specifies the attribute type GeoEvent Server will use to identify new or updated feature records when polling for incremental updates. ObjectID and Timestamp (feature record date/time) values are the only attribute types supported. ObjectID - GeoEvent Server will cache the greatest object identifier from the feature record set returned from a map/feature service poll. Only features whose object identifier is greater than the value cached from the last poll will be included in the next poll. Timestamp - GeoEvent Server will cache the greatest timestamp from the feature record set returned from a map/feature service poll. Only features whose timestamp is greater than the value cached from the last poll will be included in the next poll. Property is shown when Get Incremental Updates is set to Yes and is hidden when Get Incremental Updates is set to No.
Time Field to Identify Incremental Updates (Conditional)	The timestamp field, from the GeoEvent Definition, whose values will be used to identify timestamp-based incremental updates. This field could represent last updated time or creation time of the feature(s). Property is shown when Method to Identify Incremental Updates is set to Timestamp.
Query Definition	Specifies a logical expression used to restrict the feature records returned when polling a map/feature service feature layer. The expression is used as the predicate in a Structured Query Language (SQL) WHERE clause. Examples include: 1=1 - Default, used to construct the clause WHERE 1=1 to poll all available feature records. track_id LIKE '%AJP' - Matches feature records with the literal string AJP anywhere in the TRACK_ID string. reported_dt > timestamp '2019-04-05 22:30:00' - Matches feature records whose date/time attribute value is greater than the specified timestamp.
Use Geometry Filter	Specifies whether a geometry object should be used as a spatial filter to restrict the feature records returned when polling a map/feature service feature layer. A geometry filter, if specified, will be combined with a specified query definition to further restrict feature records returned from the feature layer query. For more information, see Geometry objects. Yes - A spatial filter will be used for querying features from the feature layer. No - A spatial filter will not be used for querying features from the feature layer.
Filter Geometry (Conditional)	The geometry object, expressed using feature JSON, used as a spatial filter. For more information on proper geometry object syntax, see Feature and Geometries. Property is shown when Use Geometry Filter is set to Yes.
Geometry Type (Conditional)	Specifies the type of geometry described by the feature JSON for the geometry filter. Supported geometry types include envelope, point, polyline, polygon, and multipoint. Property is shown when Use Geometry Filter is set to Yes.
Spatial Reference (Conditional)	Specifies the well-known ID (WKID) of the spatial reference for the geometry filter. Property is shown when Use Geometry Filter is set to Yes.
Spatial Relationship (Conditional)	Specifies the spatial relationship to use when evaluating feature records, polled from a map/feature service feature layer, to determine if they satisfy the conditions of the geometry filter. Property is shown when Use Geometry Filter is set to Yes.
Delete Polled Features	Specifies whether the feature records in the record set returned from a feature service should be deleted from the feature service feature layer. The default is No.