Attributes Reference

A compact cheat-sheet of MARS attributes. See Server ▸ Attributes for explanations and examples. Unless noted, attributes are in MARS.Core.Attributes.

Routing & verbs

Attribute	Target	Purpose
`[Path('seg')]`	class, method	Route segment (supports `{token}` and `{*}`).
`[GET]` `[POST]` `[PUT]` `[DELETE]` `[PATCH]` `[HEAD]` `[OPTIONS]`	method	HTTP verb.

Content negotiation

Attribute	Target	Purpose
`[Produces('type')]`	method, writer	Response media type(s).
`[Consumes('type')]`	method, reader	Accepted request body media type(s).
`[Encoding('UTF8')]`	method	Text encoding for serialization.

Parameter binding (on method parameters)

Attribute	Source
`[PathParam('name')]`	URL path token (always required).
`[QueryParam('name')]`	Query string.
`[FormParam('name')]`	Form field (urlencoded / multipart).
`[HeaderParam('name')]`	Request header.
`[CookieParam('name')]`	Cookie.
`[BodyParam]`	Entire request body (deserialized).
`[PathParams]` `[QueryParams]` `[Headers]` `[Cookies]` `[FormParams]`	All values of that kind as a collection.
`[Required]`	Marks a bound parameter mandatory.

Injection

Attribute	Target	Purpose
`[Context]`	field, property, parameter	Inject a framework/custom service.
`[EngineParam('Name', Default)]`	field, property, parameter	Value from engine parameters.
`[ApplicationParam('Name', Default)]`	field, property, parameter	Value from application parameters.
`[EngineParamFunc]` `[ApplicationParamFunc]`	as above	Inject a `TConfigParamFunc` for dynamic lookup.

Security

Attribute	Target	Purpose
`[PermitAll]`	resource, method	Allow everyone.
`[DenyAll]`	resource, method	Deny everyone (highest priority).
`[RolesAllowed('a','b')]`	resource, method	Require any listed role.

Response shaping

Attribute	Target	Purpose
`[ContentType('type')]`	method	Force response `Content-Type`.
`[CustomHeader('Name','Value')]`	method	Add a fixed response header.
`[IsReference]`	method	Returned object must not be freed by MARS.
`[JSONP(True, 'callback', 'text/javascript')]`	method	Wrap JSON as JSONP.

Lifecycle hooks (on resource methods)

Attribute	When
`[BeforeInvoke]`	Before the endpoint method runs.
`[AfterInvoke]`	After it returns.
`[InvokeError]`	When it raises.
`[AfterContextCleanup]`	After injected context is freed.

Metadata & OpenAPI (`MARS.Metadata.Attributes`, OpenAPI units)

Attribute	Target	Purpose
`[MetaSummary('...')]`	resource, method	Short summary.
`[MetaDescription('...')]`	resource, method, parameter	Longer description.
`[MetaVisible(False)]`	resource, method	Hide from metadata/OpenAPI.
`[OAPIDescription]` `[OAPIRequired]` `[OAPIPattern]` `[OAPIMinimum]` `[OAPIMaximum]`	record/class field	JSON-schema hints.

JSON serialization (`MARS.Core.JSON`)

Attribute	Target	Purpose
`[JSONName('key')]`	field	Custom JSON key.
`[JSONSkip]`	field	Exclude from (de)serialization.
`[JSONSkipEmptyValues]` `[JSONIncludeEmptyValues]`	field, resource, method	Empty/null inclusion policy.

Data — FireDAC (`MARS.Data.FireDAC.*`)

Attribute	Target	Purpose
`[Connection('DEFNAME')]`	resource, field, parameter	Select FireDAC connection definition.
`[SQLStatement('Name','SELECT …')]`	resource	Declare a named SQL statement.

Web server (`MARS.WebServer.Resources`)

Attribute	Target	Purpose
`[RootFolder('path', AServeIndex)]`	resource	Map a `TFileSystemResource` to a disk folder.