ArcGIS REST API Connector QGIS Plugin

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QGIS-Plugin ArcGIS REST API Connector (beta) which reads from ArcGIS Online and ArcGIS Server and the "Esri Open Data Initiative Portal Software".

  • A project by Geometa Lab HSR
  • Project Lead: Stefan Keller
  • Authors/Developers: Carmelo Schumacher, Tobias Schmitz, Rafael Krucker and Dennis Ligtenberg


About

QGIS-Plugin ArcGIS REST API Connector which reads from ArcGIS Online and ArcGIS Server and the "Esri Open Data Initiative Portal Software".

This plugin focusses on reading so-called "Maps" accessible over the Internet by interpreting JSON (JavaScript Object Notation) similar to WFS.

  • Supports HTTP "Basic Authentication" and "NTLM authentication".
  • Note that currently only reading "Feature Services" are supported.
  • "Map Services" (kind of WMTS) are NOT supported (see e.g. QuickMapServices Plugin for a solution).

Note that "Map Services" are not supported. Map Services are comparable with WMS and WMTS. They expose a set of tiled images, read-only, working with the default data frame of the published map document on the server.

Available ArcGIS Services

Query syntax and other details of the specification

From the "ArcGIS REST API" documentation:

The Query operation is performed on a feature service resource. The result is a feature sets for each layer in the query. Other result types (such as count of features and array of feature IDs for each layer in the query) are not supported.

There is a limit to the number of features included in the response (see the maxRecordCount property of the feature service).

"Feature Service" have functions similar to similar to WFS but it's a proprietary API. In ArcGIS one can

  • connect/new/edit/delete connection
  • load/save connections
  • filter layer list
  • select layer (then download)

Other implementation details of "Feature Service":

  • maxRecordCount - currently maxRecordCount is ignored.
  • Query - currently there's no query functionality.
  • outSR - currently geometry is returned as default well-known ID "GCS_WGS_1984".

Support

Project notes, issues, bugs and feature requests: See github (for older notes see tab "Diskussion").

Possible Enhancements

According to Esri's specification of "ArcGIS REST API"], there are many services: ... With ready-to-use basemaps, reference layers, and so on, you can quickly add context or a backdrop to your local or worldwide data. Some ArcGIS Online maps are thematic, which may provide all the information you need to present in your application.

Future improvements may be made to Feature Service, Map Service and additionally to a new Image Service, which provides access to raster data similar to Map Services. Both Map and Image services return raster images mosaicked on the fly or WMTS whereas the main difference is that Map Services are read-only while Image Service include an API for editing and uploading (which is out-of-scope of this plugin).

General improvements may include

  • Authentification (with OAuth 2.0)
  • HttpProxy (issue #3)

Future improvements of Feature Service may include:

  • Paging (maxRecordCount) See issue #6
  • Local Feature Cache (see [1])
  • Query and Query Related Records
  • Dealing with compressed http content?
  • Reading/showing "Services Directory"

Future improvements of Map Service may include:

  • Feature (aka OGC WMS GetFeatureInfo?)
  • Image (Marker)?
  • Legend (aka WMS GetLegend)
  • Map Tile
  • WMTS

Installation and Source Code

Install from inside QGIS as Python plugin (Note: For versions below 1 (0.1 - 0.9) you have to enable "experimental plugins").

Von «https://giswiki.hsr.ch/index.php?title=ArcGIS_REST_API_Connector_QGIS_Plugin&oldid=58108»