ARLAS-OGC-API
ARLAS Exploration offers an OGC API that makes the ARLAS catalog interoperable with GIS applications. The catalog is explorable through two standard endpoints:
- A WFS endpoint for each collection reference that provides access to the geographic features of the collection.
- A CSW endpoint to discover the available collections.
A third endpoint is available to get an Opensearch description of CSW service.
URL Schema
The table below lists the URL endpoints and their ogc "parameters". The parameters are separated with the character &.
| PATH Template | Description |
|---|---|
/arlas/ogc/wfs/{collection}?wfsParameters |
Download the features of the given {collection} |
/arlas/ogc/csw/?cswParameters |
Discover the available collections in ARLAS |
| /arlas/ogc/csw/opensearch | OpenSearch CSW Description Document |
URL Parameters
WFS Parameters
The following parameters are mandatory and must be specified for all WFS requests
| Parameter | Description | Possible values |
|---|---|---|
| service | name of the service | WFS |
| version | Supported WFS standard version | 2.0.0 |
| request | The WFS operation to perform | Six possible values. Check the table below |
The table below sums up the WFS operations supported by ARLAS-server
| Operation | Description |
|---|---|
GetCapabilities |
Generates a metadata document describing the WFS service provided by ARLAS-server as well as valid WFS operations and parameters |
DescribeFeatureType |
Returns a description of feature types supported by WFS service |
GetFeature |
Returns a selection of features from the given {collection} including geometry and attribute values |
GetPropertyValue |
Fetches the value of a given feature property of the {collection} |
ListStoredQueries |
Returns the list of the stored queries of WFS server |
DescribeStoredQueries |
Returns a metadata document describing the stored queries of WFS server |
According to the chosen operation, you can specify a set of parameters
request=GetCapabilities
You can specify a language parameter :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| language | Language of the metadata | One of the official languages of the European Community expressed in conformity with ISO 639-2 | Optional |
This parameter conforms to INSPIRE recommendations.
- If the requested language is contained in the list of supported languages, then natural language metadata elements are returned in the requested language.
- If the requested language is not supported by the WFS, then this parameter is ignored.
request=DescribeFeatureType
This operation gives information about the feature type before requesting the actual data.
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| typenames | Name of the feature type to describe | Must contain the name of the {collection} |
Optional |
request=GetFeature
This operation returns a selection of features from the given {collection}.
You can specify pagination parameters :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| count | Maximum number of returned features | Integer | Optional |
| startindex | Index to start the search from | Integer | Optional |
You can use stored queries :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| storedquery_id | Id of a storied query in WFS server. | urn:ogc:def:query:OGC-WFS::GetFeatureById |
Optional |
| id | Id of a feature to query. | text | Mandatory if storedquery_id is specified |
You can query data using the following parameters
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| resourceid | Id of a feature to query. | text | Optional |
| bbox | A geographic extend used to query any feature having its centroid contained within it. | west, south, east, north |
Optional |
| filter | A filter used to select features by evaluating an expression | Filter Encoding language 2.0.2 Reference | Optional |
| srsname | crs of the features | http://www.opengis.net/def/crs/epsg/0/4326, urn:ogc:def:crs:EPSG::4326 |
Optional |
| typenames | Name of the feature type to describe | Must contain the name of the {collection} |
Optional |
request=GetPropertyValue
This operation returns the value of a feature property.
You must specify the feature property :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| valueReference | Feature type property | text | Mandatory |
You can specify pagination parameters :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| count | Maximum number of returned features | Integer | Optional |
| startindex | Index to start the search from | Integer | Optional |
You can use stored queries :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| storedquery_id | Id of a storied query in WFS server. | urn:ogc:def:query:OGC-WFS::GetFeatureById |
Optional |
| id | Id of a feature to query. | text | Mandatory if storedquery_id is specified |
You can query data using the following parameters
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| resourceid | Id of a feature to query. | text | Optional |
| bbox | A geographic extend used to query any feature having its centroid contained within it. | west, south, east, north |
Optional |
| filter | A filter used to select features by evaluating an expression | Filter Encoding language 2.0.2 Reference | Optional |
| typenames | Name of the feature type to describe | Must contain the name of the {collection} |
Optional |
Note
bboxandresourceidcan't be used togetherbboxandfiltercan't be used togetherresourceidandfiltercan't be used together
CSW Parameters
The following parameters are mandatory and must be specified for all CSW requests
| Parameter | Description | Possible values |
|---|---|---|
| service | name of the service | CSW |
| version | Supported CSW standard version | 3.0.0 |
| request | The CSW operation to perform | Three possible values. Check the table below |
The table below sums up the CSW operations supported by ARLAS-server
| Operation | Description |
|---|---|
GetCapabilities |
Generates a metadata document describing the CSW service provided by ARLAS-server as well as valid CSW operations and parameters |
GetRecords |
Returns collection references metadata and identifier |
GetRecordById |
Returns a specific collection reference metadata and identifier |
According to the chosen operation, you can specify a set of parameters
request=GetCapabilities
You can specify a language parameter :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| language (1) | Language of the metadata | One of the official languages of the European Community expressed in conformity with ISO 639-2 | Optional |
| sections | Specifies which parts of the GetCapabilities response to include | ServiceIdentification, ServiceProvider, OperationsMetadata, Filter_Capabilities, All |
Optional |
(1) This parameter conforms to INSPIRE recommendations.
- If the requested language is contained in the list of supported languages, then natural language metadata elements are returned in the requested language.
- If the requested language is not supported by the WFS, then this parameter is ignored.
request=GetRecords & request=GetRecordById
The following parameters are common to GetRecords and GetRecordById
You can specify pagination parameters :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| maxRecords | Maximum number of returned collections | Integer | Optional |
| startposition | Index to start the search from | Integer | Optional |
You can choose which metadata to return :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| elementName | Metadata elements to return (1). | Comma separated metadata elements. For instance : title,subject. |
Optional |
| elementSetName | Group of metada elements to return. | brief, summary (default) or full |
Optional |
| typenames | Defines the level of details present in the result set. | Record, csw:Record or gmd:MD_Metadata |
Optional |
(1) Possible values of elementName are : title, abstract, identifier, subject, creator, publisher, contributor, type, format, source, language, modified, boundingbox.
Note
elementNameandelementSetNamecan't be used together
You can choose the format :
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| outputFormat | Whether to return response in application/xml or application/atom+xml format |
application/xml (default), application/atom%2Bxml |
Optional |
| outputSchema | The schema of output of GetRecords/GetRecordById response | http://www.opengis.net/cat/csw/3.0.0 (default) or http://www.isotc211.org/2005/gmd |
Optional |
You can query collection references metadata using the following parameters
| Parameter | Description | Possible values | Mandatory/Optional |
|---|---|---|---|
| recordIds | Comma separated ids of collections | text | Optional |
| id | id of a collection | text | Mandatory for GetRecordById |
| q | Full text search on collection references | text | Optional |
| bbox | A geographic extend used to query any collection that intersects it. | west, south, east, north |
Optional |
| constraint | A filter used to select collections references by evaluating an expression | Filter Encoding language 2.0.2 Reference | Optional |
| constraintLanguage | Language of the constraint | Filter |
Optional |
Note
bboxandrecordidscan't be used togetherrecordidsandqcan't be used together