USER MANUALS

RESTful Web Service

The RESTful Web service of the Denodo Platform is an HTTP service that publishes the contents of the entire Virtual DataPort server.

Unless explicitly mentioned in the documentation, you can use the RESTful web service in the same way as published REST web services: the input parameters are the same and the output has the same format.

The output of this service can be an XML document, a JSON document or a more user-friendly HTML document.

This web service is deployed in the URL http://<host of the Denodo server>:9090/denodo-restfulws and exposes the following types of resources:

Types of resources exposed by the RESTful Web service

Type of Resource

URI Format

Representation

Databases

/<database name>

Shows the database description and the list of views in the database, including links to access their schema and their elements.

Views

/<database name>/views/<view name>

Shows the metadata of the view and lists the elements of the view.

Row of a view

/<database name>/views/<view name> /<pk field 1>, <pk field 2>

Shows the data of an individual row of a view, if the view has its primary key defined.

Number of rows of a of a result set

/<database name>/views/<view name> /$count

Returns the number of rows of the view. It can be used in combination with filters by field and/or the parameter $filter.

See more about obtaining the number of rows of a result set in the section Obtaining the Number of Rows of a Result Set

Metadata of a view

/<database name>/views /<view name>/$metadata

Returns the metadata of the view. This includes the description of the view and the URLs to retrieve its schema and its associations.

This URL is only supported in the XML and JSON representations, not the HTML one. This means that to obtain the to send the appropriate Accept metadata of a view, you either have header or add ?$format=xml or ?$format=json to the URL.

Schema of a view

/<database name>/views /<view name>/$schema

Returns the schema of the view. This a list of the fields and types of the view.

This URL is only supported in the XML and JSON representations, not the HTML one. This means that to obtain the schema, you either have to send the appropriate Accept header or add ?$format=xml or ?$format=json to the URL.

When you request the schema of a view of a REST web service, not the RESTful web service, consider the following:

  • REST services only return the fields that are published; in the configuration of the service, you may have removed some of the fields of the view.

  • REST services return the names of the fields as they appear in the web service, not the name of the fields in the view; in the configuration of the service, you may have renamed some fields.

Schema of a view (XSD)

/<database name>/views /<view name>/$xsd

Returns the schema of the view in XSD format. This is equivalent to /<database name>/views/<view name>/$schema?$format=xml.

This URL is only supported in the XML representation.

Associations

/<database name>/views /<view name>/$associations

Returns the associations of the view.

This URL is only supported in the XML and JSON representations, not the HTML one. This means that to obtain the associations, you either have to send the appropriate Accept header or add ?$format=xml or ?$format=json to the URL.

When you request the associations of a view of a REST web service, not the RESTful web service, the service will only return the associations that are published with the service, not all the associations of the view.

OpenAPI 2 / Swagger specifications

/OpenAPI/swagger.json /OpenAPI/swagger.yaml

This is only available for REST web services, not the RESTful web service

Returns the OpenAPI 2 / Swagger specification for a published REST web service in JSON or YAML format. The specification is based on the views published by the web service and describes the available operations, the parameters that are available for each one and their input and output schemas.

You can load the generated specifications in https://editor.swagger.io. Here you will be able to visualize the specification’s details, generate client code automatically and obtain example requests for accessing the web service.

Examples of how to invoke the RESTful Web service

  • http://localhost:9090/denodo-restfulws/admin returns the list of views of the database admin.

  • http://localhost:9090/denodo-restfulws/admin/views/customer returns the content of the view customer of the database admin.

  • http://localhost:9090/denodo-restfulws/admin/views/customer/1/orders browses through the mapping orders of the row of the table customer whose primary key is 1.


Additional notes about the URI format of the RESTful Web service

  • URLs are case-sensitive. This means that a view TestView must be invoked with http://.../views/TestView, and not http://.../admin/views/testview.

  • If the value of the primary key contains the character ,, replace it with %2C. This is because the character , separates the values of the primary key with more than one field. E.g. http://.../support/views/viewA/1,value%2Cwith%2Ccommas.

  • String literals must not be quoted, except in the $filter parameter (see section Input Parameters of the RESTful Web Service to see additional information about the parameters of the RESTful Web service).

Following the RESTful conventions, the statement sent to Virtual DataPort by the RESTful Web service, depends on the HTTP method of the request.

The table RESTful Web service: HTTP methods and their equivalent VQL statements displays the type of query sent by the Service depending on the HTTP method of the request and the syntax of the URL depending on the type. For the GET requests, the syntax can vary a lot and is explained in the following section.

RESTful Web service: HTTP methods and their equivalent VQL statements

VQL Statement

HTTP Method

Syntax of the Request URL

SELECT

GET

http://localhost:9090/denodo-restfulws/

INSERT

POST

http://localhost:9090/denodo-restfulws/<database name>/views/<view name>

UPDATE

PUT

http://localhost:9090/denodo-restfulws/<database name>/views/<view name>/<primary key value>

DELETE

DELETE

http://localhost:9090/denodo-restfulws/<database>/views/<view name>/<primary key value>
Add feedback