wiki:Clients

Version 66 (modified by Peter Baumann, 14 months ago) ( diff )

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  1. Clients
    1. Domain-Agnostic Array Access
      1. Rasql query language access
        1. Command Line
        2. Web API
        3. Directql
      2. python
      3. R
      4. raswct (rasdaman Web Client Toolkit)
      5. THREDDS (scientific data catalog)
    2. Geo clients
      1. Web Services client
      2. NASA WebWorldWind (Web-based virtual globe)
      3. OpenLayers and Leaflet (Web-based map navigation)
      4. ncWMS (Web-based climate data navigation)
      5. QGIS WCPS plugin
      6. MapServer (Web GIS server)
      7. GeoServer (Web GIS server)
      8. ESRI ArcGIS (GIS tool)
    3. Not Supported currently

Clients

It is important for data users to get convenient access to rasdaman functionality, for manifold reasons: users want to stay in their well-known environments (such as QGIS, ESRI, or R); users have additional functionality in their tools which they want to apply on data retrieved from rasdaman; users do not want to learn yet another data language. To this end, a large and increasing number of tools can access rasdaman today, thereby enabling these with flexible, scalable server-side processing of n-D "Big Array Data". They largely fall into two categories, rasdaman-provided and "external" third-party tools. Below they are listed and explained.

rasdaman can interface with a large and increasing number of tools. Some clients allow direct query submission, such as rasql and directql. For rapid development of browser clients the raswct toolkit is provided.

Geo tools supported include OpenLayers, QGIS, ncWMS, THREDDS, GDAL, MapServer, !ArcGIS; soon: GeoServer. Geo standards supported are OGC WMS, WCS, WCPS, and WPS; hence, all clients conforming to these standards can additionally be used for interfacing. All geo semantics is implemented through the petascope component (​source) which is implemented as a Java application layer offering OGC Web services.

Domain-Agnostic Array Access

Rasql query language access

Command Line

The rasql client allows to submit rasql queries via command line and save results in local files.

Invocation example (see rasql --help for details):

  • retrieve the (single array in the) mr collection, in PNG format 
    rasql -q 'select encode( mr, "png" ) from mr' --out file
  • list array collections in the database: 
    rasql -q 'select c from RAS_COLLECTIONNAMES as c' --out string

Web API

rasql queries can also be submitted via a Web service, by default listening at localhost:8080/rasdaman/rasql. To this end, the corresponding servlet needs to be started (see the Installation Guide).

Syntax: 

http://{service}/{path}/rasdaman/rasql?params

Example: 
http://www.acme.com/rasdaman?query=select%20rgb.red+rgb.green%20from%20rgb&username=rasguest&password=rasguest
  • This servlet endpoint accepts KVP requests with the following parameters:
    • query=q where q is a valid rasql query, appropriately escaped as per http pecification.
    • username=u where u is the user name for logging into rasdaman (current: rasguest for retrieval query (select) and rasadmin for the editable query (insert, update, delete,…).
    • password=p where p is the password for logging into rasdaman (current: rasguest for username: rasguest and rasadmin for username: rasadmin).
  • To upload data to server, it is needed to attach the data in HTTP message's body and send the POST request to the Servlet endpoint with user have the write permission (e.g: rasadmin). In Linux, one tool can support this feature is cURL. Syntax: 
    curl -F 'image=@{/Path_To_Image}' '{http://Rasql_Servlet_Endpoint?username=rasadmin&password=rasadmin&query={insert/update query}'
    • Here is an example: 
      Collection: test_mr_test1

Insert file to collection:
curl -F 'image=@/home/rasdaman/rasdaman/systemtest/testcases_services/test_all_wcst_import/test_data/wcps_mr/mr_1.png' 'http://localhost:8080/rasdaman/rasql?username=rasadmin&password=rasadmin&query=insert%20into%20test_mr_test1%20values%20decode(%241)' 

Update file to collection:
curl -F 'image=@/home/rasdaman/rasdaman/systemtest/testcases_services/test_all_wcst_import/test_data/wcps_mr/mr_1.png' 'http://localhost:8080/rasdaman/rasql?username=rasadmin&password=rasadmin&query=update%20test_mr_test1%20set%20test_mr_test1%20assign%20decode(%241)'

Directql

directql is not strictly a client, but a rasdaman server linked directly with the rasql utility (see above), rather than following the client/server architecture. Main purpose is simplified debugging of the server by allowing command-line invocation of the server engine. See (​source).

python

R

RRasdaman is an R package providing a database interface for rasdaman, i.e.: for submitting rasdaman queries from within R. It is submitted to CRAN. See installation/setup guide and tutorial for more information.

raswct (rasdaman Web Client Toolkit)

This JavaScript library allows, by way of input and output widgets, to easily compose a Web client. Simple versions need only HTML, but advanced interfaces can be created. One example for the use of raswct is ​standards.rasdaman.org. See documentation for details.

THREDDS (scientific data catalog)

documentation tbd

Geo clients

Web Services client

This ​source generic Web client allows for convenient forms-based input of WCS parameters for WCS Core and Extensions on the level of requests.

All WCS extensions are supported, but the client presents only those extensions which are supported by the server addressed. Results can be displayed graphically where feasible. A coverage can be showed its footprint on WebWorldWind globe in WS Web Client when it is imported as 2D+ geo-referenced coverage.

NASA WebWorldWind (Web-based virtual globe)

NASA WebWorldWind is a highly flexible open-source virtual globe toolkit, programmed in JavaScript, running in Web browsers. It can be configured to display rasdaman results via OGC WCPS queries.

For coding instructions, two sources are available: The built-in geo client of rasdaman makes use of WebWorldWind; further, an example using a WCPS query to display a time series of average chlorophyll concentration is available at ​Earthlook. See more about ​WebWorldWind tutorials.

NOTE: WebWorldWind with WMS GetMap request does not divide to smaller bounding boxes at very close zoom distance (e.g: 1km above ground). Hence, layers with very high resolution cannot be shown in detail as original input files.

OpenLayers and Leaflet (Web-based map navigation)

Via WMS 1.3, OpenLayers and Leaflet can connect directly to a rasdaman WMS endpoint.

ncWMS (Web-based climate data navigation)

documentation tbd

QGIS WCPS plugin

QGIS can directly download, process, integrate, and use coverages from rasdaman via plugins [​​https://plugins.qgis.org/plugins/QgsWcsClient2/ for WCS] and for [​​https://plugins.qgis.org/plugins/QgsWcpsClient1/ WCPS] being part of the official QGIS plugin repository. Alternatively, the source code of the WCPS plugin is available from rasdaman.

Check these ​step-by-step plugin installation instructions. In a nutshell:

  • select QGIS menu Plugins → Manage and Install Plugins → Search: wcps (it returns the plugin QgsWcpsClient1) → click install
  • now you can access the QgsWcpsClient1 plug-in via the Qgis Menu → Plugins → WcpsClient1 → WCPS 1.0 Client
  • select Help tab from the QgsWcpsClient1 plug-in window for information about how to connect to a WCPS endpoint.

Another QGIS plugin is ​available on github. Installing it under Ubuntu is no problem, under Windows there might be an issue with the lxml module used by the plugin; if this occurs follow ​these instructions.

MapServer (Web GIS server)

documentation tbd

GeoServer (Web GIS server)

documentation tbd

ESRI ArcGIS (GIS tool)

Starting version 10.3, ESRI ArcGIS supports WCS 2. Hence, access from ArcGIS to rasdaman via WCS 2 is expected to be possible (in lack of an ArcGIS license we cannot verify).

Not Supported currently

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