Introduction to SCIM


SCIM protocol enables developers to support a standard way to provision, update, and manage identities from customer and partner organizations. SCIM helps reduce costs integrating services by:

Where is SCIM Used?

In some cases, SCIM is deployed as a directory server such as with Microsoft Azure or Oracle Identity Cloud Service (IDCS). As a directory, many applications can access a common stateful store for User profile information. Similarly SCIM servers often serve as the backing store for OAuth Authorization and OpenId Connect systems.

SCIM is also used (as originally intended) as a provisioning service enabling a common open API to create and update User accounts in cloud based applications and services (e.g. SFDC).

What is SCIM Schema?

In the JSON world “schema” can be a controversial topic. In the SCIM world because many service providers will implement SCIM, there had to be a way to tell SCIM clients how to read and understand service endpoints with slightly different set-ups. For example, one server may have only Users and Groups (the most common), but other servers may have other custom resource types like Devices, Applications, etc.

In a SCIM server, resources are collected in top-level containers known as Resource Types. Each resource (record) has a defined “schema” which lays out the attributes contained within the record, their characteristics and types (e.g. boolean). In addition to a main “schema”, an individual resource may be extended with additional attributes known as an extension schema. This enables applications to attach local attributes, while preserving inter-operability with the standardized attributes such as defined in the User schema.

SCIM standardizes common attributes (aka claims) about Users and Groups RFC7643. Users, Groups, and other objects are handled as JSON documents (aka resources). SCIM schema defines attribute types:

For each attribute defined, there are also a set of characteristics that define how to parse and how the attribute is used:

Core Attributes

SCIM defines the following core attributes that are present in every SCIM Resource:

An important aspect of SCIM is that all resource URIs a permanent - not subject to change. By using a globally unique identifier, external references (e.g. such as to Users within Groups) are not subject to link breakages. This provides SCIM services with a natural form of referential integrity.

An example SCIM Resource document:


 "id": "2819c223-7f76-453a-413861904646",
 "externalId": "701984",

 "userName": "bjensen@example.com",
 "name": {
   "formatted": "Ms. Barbara J Jensen, III",
   "familyName": "Jensen",
   "givenName": "Barbara",
   "middleName": "Jane",
   "honorificPrefix": "Ms.",
   "honorificSuffix": "III"
 "...other core attrs...": "..vals.",

 "urn:ietf:params:scim:schemas:extension:enterprise:2.0:User": {
   "employeeNumber": "701984",
   "costCenter": "4130",
   "...other extension attrs...": "..vals."

 "meta": {
   "resourceType": "User",
   "created": "2010-01-23T04:56:22Z",
   "lastModified": "2011-05-13T04:42:34Z",
   "version": "W\/\"3694e05e9dff591\"",

SCIM API / Protocol

SCIM Protocol RFC7644 is technically just a profile of HTTP RFC7230-40. In other words, SCIM is just a REST-ful API that defines things like create, read/search, update and delete methods using HTTP methods.

{ “schemas”:[“urn:ietf:params:scim:schemas:core:2.0:User”], “userName”:”bjensen”, “externalId”:”bjensen”, “name”:{ “formatted”:”Ms. Barbara J Jensen III”, “familyName”:”Jensen”, “givenName”:”Barbara” } }

   The server responds with:
```http request
HTTP/1.1 201 Created
Content-Type: application/scim+json
Location: https://example.com/v2/Users/2819c223-7f76-453a-919d-413861904646
ETag: W/"e180ee84f0671b1"

    "location": "https://example.com/v2/Users/2819c223-7f76-453a-919d-413861904646",
    "formatted":"Ms. Barbara J Jensen III",

Example SCIM Patch request to remove a User from a group… ```http request PATCH /Groups/acbf3ae7-8463-…-9b4da3f908ce Host: example.com Accept: application/scim+json Content-Type: application/scim+json Authorization: Bearer h480djs93hd8 If-Match: W/”a330bc54f0671c9”

{ “schemas”: [“urn:ietf:params:scim:api:messages:2.0:PatchOp”], “Operations”:[{ “op”:”remove”, “path”:”members[value eq "2819c223-7f76-…413861904646"]” }] }

Example SCIM Patch to remove all members of a group...
```http request
PATCH /Groups/acbf3ae7-8463-...-9b4da3f908ce
Host: example.com
Accept: application/scim+json
Content-Type: application/scim+json
Authorization: Bearer h480djs93hd8
If-Match: W/"a330bc54f0671c9"

{ "schemas": ["urn:ietf:params:scim:api:messages:2.0:PatchOp"],

In addition to the basic CRUD methods above, i2scim also supports the following HTTP protocol items: