Create custom endpoints to launch scripts

Custom endpoints let you run arbitrary scripts through the REST API.

A custom endpoint configuration includes an inline script, or script file reference, in either JavaScript or Groovy. The script provides the endpoint functionality.

A sample custom endpoint configuration is provided in the openidm/samples/example-configurations/custom-endpoint directory. The sample includes three files:

conf/endpoint-echo.json: Provides the configuration for the endpoint.
script/echo.js: Provides the endpoint functionality in JavaScript.
script/echo.groovy: Provides the endpoint functionality in Groovy.

This sample endpoint is described in detail in the sample: Create a custom endpoint.

Custom endpoint configuration

A custom endpoint configuration has the following structure:

{
    "context" : "context path",
    "type" : "script language",
    "source" : "script source" | "file" : "script file",
    "apiDescription" : "API descriptor object"
}

context

string, optional

The root URL path for the endpoint, in other words, the route to the endpoint. An endpoint with the context endpoint/test is addressable over REST at the URL http://localhost:8080/openidm/endpoint/test or by using a script such as openidm.read("endpoint/test").

Endpoint contexts support wild cards, as shown in the preceding example. The endpoint/linkedview/* route matches the following patterns:

endpoint/linkedView/managed/user/bjensen
endpoint/linkedView/system/ldap/account/bjensen
endpoint/linkedView/
endpoint/linkedView

The context parameter is not mandatory in the endpoint configuration file. If you do not include a context, the route to the endpoint is identified by the name of the file. For example, in the sample endpoint configuration provided in openidm/samples/example-configurations/custom-endpoint/conf/endpoint-echo.json, the route to the endpoint is endpoint/echo.

type

string, required

The script type.

IDM supports "text/javascript" and "groovy".

file or source

The path to the script file, or the script itself, inline.

For example:

"file" : "workflow/gettasksview.js"

"source" : "require('linkedView').fetch(request.resourcePath);"

apiDescription

JSON object, optional

Describes the custom endpoint and includes its documentation in the REST API Explorer.

You must set authorization for any custom endpoints that you add, for example, by restricting the methods to the appropriate roles. For more information, refer to Authorization and Roles.

Custom endpoint scripts

The custom endpoint script files in the samples/example-configurations/custom-endpoint/script directory demonstrate all the HTTP operations that can be called by a script. Each HTTP operation is associated with a method (create, read, update, delete, patch, action, or query). Requests sent to the custom endpoint return a list of the variables available to each method.

All scripts are invoked with a global request variable in their scope. This request structure carries all the information about the request.

Read requests on custom endpoints must not modify the state of the resource, either on the client or the server, as this can make them susceptible to CSRF exploits.

The standard READ endpoints are safe from Cross Site Request Forgery (CSRF) exploits because they are inherently read-only. That is consistent with the Guidelines for Implementation of REST, from the US National Security Agency, as "… CSRF protections need only be applied to endpoints that will modify information in some way."

Custom endpoint scripts must return a JSON object. The structure of the return object depends on the method in the request.

The following example shows the create method in the echo.js file:

if (request.method === "create") {
    return {
        method: "create",
        resourceName: request.resourcePath,
        newResourceId: request.newResourceId,
        parameters: request.additionalParameters,
        content: request.content,
        context: context.current
    }
}

The following example shows the query method in the echo.groovy file:

else if (request instanceof QueryRequest) {
    // query results must be returned as a list of maps
    return [
        [
            method: "query",
            resourceName: request.resourcePath,
            pagedResultsCookie: request.pagedResultsCookie,
            pagedResultsOffset: request.pagedResultsOffset,
            pageSize: request.pageSize,
            queryId: request.queryId,
            queryFilter: request.queryFilter.toString(),
            parameters: request.additionalParameters,
            context: context.toJsonValue().getObject()
        ]
    ]
}

Depending on the method, the variables available to the script can include the following:

resourceName: The name of the resource, without the endpoint/ prefix, such as echo.
newResourceId: The identifier of the new object, available as the results of a create request.
revision: The revision of the object.
parameters: Any additional parameters provided in the request. The sample code returns request parameters from an HTTP GET with ?param=x, as "parameters":{"param":"x"}.
content: Content based on the latest revision of the object, using getObject.
context: The context of the request, including headers and security. For more information, refer to Request context chain.
Paging parameters: The pagedResultsCookie, pagedResultsOffset, and pageSize parameters are specific to query methods. For more information refer to Page Query Results.
Query parameters: The queryId and queryFilter parameters are specific to query methods. For more information refer to Construct Queries.

Script exceptions

Some custom endpoint scripts require exception-handling logic. To return meaningful messages in REST responses and in logs, you must comply with the language-specific method of throwing errors.

A script written in JavaScript should comply with the following exception format:

throw {
    "code": 400, // any valid HTTP error code
    "message": "custom error message",
    "detail" : {
        "var": parameter1,
        "complexDetailObject" : [
            "detail1",
            "detail2"
        ]
    }
}

Any exceptions will include the specified HTTP error code, the corresponding HTTP error message, such as Bad Request, a custom error message that can help you diagnose the error, and any additional detail that you think might be helpful.

A script written in Groovy should comply with the following exception format:

import org.forgerock.json.resource.ResourceException
import org.forgerock.json.JsonValue

throw new ResourceException(404, "Your error message").setDetail(new JsonValue([
    "var": "parameter1",
    "complexDetailObject" : [
        "detail1",
        "detail2"
    ]
]))

Write an API descriptor for a custom endpoint

Most IDM endpoints are described in the REST API Explorer. Documentation is not generated automatically for custom endpoints.

To generate the documentation for your custom endpoint in the API Explorer, add an apiDescription object to your custom endpoint configuration file. The apiDescription object includes the following properties:

title: The endpoint name, which expresses its purpose. For example, Audit, or Authentication.
description: A description of the endpoint.
mvccSupported: Boolean, true or false.

Indicates whether object versioning is supported. If you want to use If-None-Match or If-Match headers in read, delete, and patch requests, you must set "mvccSupported" : true.
Operations: An object that describes each operation supported on that endpoint (create, read, update, delete, patch, actions, and queries).
resourceSchema: The schema for the objects at this endpoint.

To refer to examples of the API descriptors included in IDM, log in to the admin UI then point your browser to http://localhost:8080/openidm?_crestapi.

Compare the descriptors at that URL with what you refer to in the API Explorer.

In addition, the sample configuration file (openidm/samples/example-configurations/custom-endpoint/conf/endpoint-echo.json) shows how API descriptors must be constructed:

Sample API Descriptor Object

{
    "apiDescription" : {
        "title" : "Echo",
        "description" : "Service that echo's your HTTP requests.",
        "mvccSupported" : false,
        "create" : {
            "description" : "Echo a CREATE request.",
            "mode" : "ID_FROM_SERVER",
            "singleton" : false
        },
        "read" : { "description" : "Echo a READ request." },
        "update" : { "description" : "Echo an UPDATE request." },
        "delete" : { "description" : "Echo a DELETE request." },
        "patch" : {
            "description" : "Echo a PATCH request.",
            "operations" : [ "ADD", "REMOVE", "REPLACE", "INCREMENT", "COPY", "MOVE", "TRANSFORM" ]
        },
        "actions" : [
            {
                "description" : "Echo an ACTION request.",
                "name" : "echo",
                "request" : { "type" : "object" },
                "response" : {
                    "title" : "Echo action response",
                    "type" : "object",
                    "properties" : {
                        "method" : {
                            "type" : "string",
                            "enum" : [ "action" ]
                        },
                        "action" : { "type" : "string" },
                        "content" : { "type" : "object" },
                        "parameters" : { "type" : "object" },
                        "context" : { "type" : "object" }
                    }
                }
            }
        ],
        "queries" : [
            {
                "description" : "Echo a query-filter request.",
                "type" : "FILTER",
                "queryableFields" : [ "*" ]
            },
            {
                "description" : "Echo a query-all request.",
                "type" : "ID",
                "queryId" : "query-all"
            },
            {
                "description" : "Echo a query-all-ids request.",
                "type" : "ID",
                "queryId" : "query-all-ids"
            }
        ],
        "resourceSchema" : {
            "title" : "Echo resource",
            "type" : "object",
            "properties" : {
                "method" : {
                    "title" : "CREST method",
                    "type" : "string"
                },
                "resourceName" : { "type" : "string" },
                "parameters" : { "type" : "object" },
                "context" : { "type" : "object" }
            }
        }
    }
}

This object generates API documentation in the API explorer that looks like this:

IDM 7.3.1

Create custom endpoints to launch scripts

Custom endpoint configuration

Custom endpoint scripts

Script exceptions

Write an API descriptor for a custom endpoint