Schema Extensions

EzSCIM uses a declarative, opt-in attribute system. You annotate your C# classes with [ScimProperty] to control exactly which fields are exposed via SCIM and how they are described in the auto-generated /scim/Schemas endpoint.

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Annotations

[ScimResource] — class level

Defines the SCIM schema URN and metadata for a resource class.

using EzSCIM.Attributes;

[ScimResource(
    "urn:ietf:params:scim:schemas:core:2.0:User",
    "User",
    "User Account"
)]
public class ScimUser { ... }

Parameter	Description
Schema	SCIM schema URN (required)
Name	Resource name (required)
Description	Resource description (required)

[ScimProperty] — property level

Marks a property as part of the SCIM schema. Only annotated properties are included in generated schemas and mapped by filter translators.

[ScimProperty("userName", "string", Required = true, Uniqueness = "server")]
public string UserName { get; set; }

Parameter	Type	Default	Description
Name	string	—	SCIM attribute name (required)
Type	string	—	SCIM data type (required) — see below
Required	bool	false	Attribute is required
MultiValued	bool	false	Attribute allows multiple values
Description	string	""	Attribute description
Uniqueness	string	"none"	none, server, global
Mutability	string	"readWrite"	readOnly, readWrite, immutable, writeOnly
Returned	string	"default"	always, never, default, request
CaseExact	bool	false	Case-sensitive value comparison

SCIM data types

string, boolean, complex, reference, dateTime, integer, decimal, binary

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Extend ScimUser with custom attributes

Inherit ScimUser and annotate custom properties:

using EzSCIM.Attributes;
using EzSCIM.Models;

[ScimResource(
    "urn:enterprise:params:scim:schemas:extension:Acme:2.0",
    "AcmeUser",
    "Acme Corporation user with enterprise attributes"
)]
public class AcmeUser : ScimUser
{
    [ScimProperty("employeeNumber", "string",
        Required = true,
        Uniqueness = "server",
        Description = "Unique employee ID")]
    public string EmployeeNumber { get; set; } = string.Empty;

    [ScimProperty("department", "string",
        Description = "Department code")]
    public string? Department { get; set; }

    [ScimProperty("hireDate", "dateTime",
        Description = "Date of hire")]
    public DateTime? HireDate { get; set; }

    [ScimProperty("costCenters", "string",
        MultiValued = true,
        Description = "Assigned cost centers")]
    public List<string> CostCenters { get; set; } = new();
}

Inheritance

All [ScimProperty] annotations from ScimUser are automatically inherited. The generated schema contains both base and extension attributes.

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Extend ScimGroup

[ScimResource(
    "urn:enterprise:params:scim:schemas:extension:Acme:2.0:Group",
    "AcmeGroup",
    "Acme Corporation group"
)]
public class AcmeGroup : ScimGroup
{
    [ScimProperty("description", "string",
        Description = "Group description")]
    public string? Description { get; set; }

    [ScimProperty("ownerEmail", "string",
        Description = "Group owner email")]
    public string? OwnerEmail { get; set; }
}

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Complex nested types

Complex attribute with sub-attributes

Nested complex attributes (sub-objects) also use [ScimProperty]:

[ScimProperty("badge", "complex", Description = "Badge information")]
public BadgeInfo? Badge { get; set; }

public class BadgeInfo
{
    [ScimProperty("badgeNumber", "string", Description = "Badge ID")]
    public string? BadgeNumber { get; set; }

    [ScimProperty("accessLevel", "integer", Description = "Access level 1-5")]
    public int AccessLevel { get; set; }

    [ScimProperty("expiryDate", "dateTime", Description = "Expiry date")]
    public DateTime? ExpiryDate { get; set; }
}

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URN naming convention

Use the correct URN format for custom schemas

urn:enterprise:params:scim:schemas:extension:{OrganizationName}:{Version}

Examples:

• urn:enterprise:params:scim:schemas:extension:Contoso:2.0
• urn:enterprise:params:scim:schemas:extension:AcmeCorp:1.0

Do not reuse SCIM core URNs

• urn:ietf:params:scim:schemas:core:2.0:User ← official only
• urn:ietf:params:scim:schemas:core:2.0:Group ← official only

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Schema generation

EzSCIM auto-generates the /scim/Schemas response from your annotated classes via reflection. The generator is called once at startup and cached.

// Access the generated schema (e.g. to add it to a custom schemas response)
var userSchema = ScimSchemaGenerator.GetSchema<AcmeUser>();
var groupSchema = ScimSchemaGenerator.GetSchema<AcmeGroup>();

Validate schema loading at startup

var schema = ScimSchemaGenerator.GetSchema<AcmeUser>();
if (schema.Attributes.Count == 0)
    app.Logger.LogWarning("AcmeUser schema has no attributes — check [ScimProperty] annotations");
else
    app.Logger.LogInformation("AcmeUser schema: {Count} attributes", schema.Attributes.Count);

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Register custom types in DI

When using AcmeUser and AcmeGroup instead of the base ScimUser / ScimGroup:

// Data repository (IQueryable path)
builder.Services.AddScoped<IUserGroupDataRepository<AcmeUser, AcmeGroup>, AcmeRepository>();
builder.Services.AddScoped<IScimFilterTranslator<AcmeUser>, GenericScimFilterTranslator<AcmeUser>>();
builder.Services.AddScoped<IScimFilterTranslator<AcmeGroup>, GenericScimFilterTranslator<AcmeGroup>>();

// SCIM repository for the custom types
builder.Services.AddScoped<IScimUserGroupRepository<AcmeUser, AcmeGroup>, AcmeScimRepository>();

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