Retrieving Associations Using WSO2 G-Reg Registry API Explained

This was a burning issue I had while implementing a client to retrieve association related data. In this post, I will be rewriting WSO2 official documentation for Association registry REST API. Without further a due let's send some requests and get some response :).

The following terms explain the meaning of the query parameters passed with the following REST URIs.

Parameter	Explanation
path	Path of the resource(a.k.a. registry path).
type	Type of association. By default, Governance Registry has 8 types of association, such as usedBy, ownedBy...
start	Start page number.
size	Number of associations to be fetched.
target	Target resource path(a.k.a. registry path).

Please note that the { start page } and { number of records } parameters can take any value greater than or equal to 0. The { start page } and { number of records } begins with 1. If both of them are 0, then all the associations are retrieved.

Get all the Associations on a Resource

Attributes	Values
HTTP Method	GET
Request URI	/resource/1.0.0/associations?path={ resource path }&start={ start page }&size={ number of records }
HTTP Request Header	Authorization: Basic { base64encoded(username:password) }
Response	It retrieves all the associations posted on the specific resource.
Response	HTTP 200 OK
Response Type	application/json

Sample Request and Response

Get Associations of Specific Type on a Given Resource

Attributes	Values
HTTP Method	GET
Request URI	/resource/1.0.0/associations?path={ resource path }&type={ association type }
HTTP Request Header	Authorization: Basic { base64encoded(username:password) }
Description	It retrieves all the associations for the specific type of the given resource
Response	HTTP 200 OK
Response Type	application/json

Sample Request and Response

Add Associations to a Resource

1. Using a Json pay load

Attributes	Values
HTTP Method	POST
Request URI	/resource/1.0.0/associations?path={resource path}
HTTP Request Header	Authorization: Basic { base64encoded(username:password) } Content-Type: application/json
Payload	[{ "type":"<type of the association>","target":"<valid resource path>"}]
Description	It adds the array of associations passed as the payload for the source resource
Response	HTTP 204 No Content.
Response Type	application/json

    2. Using Query Params

Attributes	Values
HTTP Method	POST
Request URI	/resource/1.0.0/associations?path={resource path}&targetPath={target resource}&type={assocation type}
HTTP Request Header	Authorization: Basic { base64encoded(username:password) } Content-Type: application/json
Response	HTTP 204 No Content.
Response Type	application/json

Delete Associations on a Given Resource

Attributes	Values
HTTP Method	DELETE
Request URI	/resource/1.0.0/association?path={resource path}&targetPath={target path}&type={association type}
Description	It deletes the association between the source and target resources for the given association type.
Response	HTTP 204 No Content.
Response Type	application/json

Again this is a detailed version of WSO2 official documentation. This concludes the post.