Attribute Macro rocket_codegen::put [−][src]
#[put]
Expand description
Attribute to generate a Route
and associated metadata.
This and all other route attributes can only be applied to free functions:
#[get("/")]
fn index() -> &'static str {
"Hello, world!"
}
There are 7 method-specific route attributes:
get
-GET
specific routeput
-PUT
specific routepost
-POST
specific routedelete
-DELETE
specific routehead
-HEAD
specific routeoptions
-OPTIONS
specific routepatch
-PATCH
specific route
Additionally, route
allows the method and path to be explicitly
specified:
#[route(GET, path = "/")]
fn index() -> &'static str {
"Hello, world!"
}
Grammar
The grammar for all method-specific route attributes is defined as:
route := '"' path ('?' query)? '"' (',' parameter)*
path := ('/' segment)*
query := segment ('&' segment)*
segment := URI_SEG
| SINGLE_PARAM
| MULTI_PARAM
parameter := 'rank' '=' INTEGER
| 'format' '=' '"' MEDIA_TYPE '"'
| 'data' '=' '"' SINGLE_PARAM '"'
SINGLE_PARAM := '<' IDENT '>'
MULTI_PARAM := '<' IDENT '..>'
URI_SEG := valid, non-percent-encoded HTTP URI segment
MEDIA_TYPE := valid HTTP media type or known shorthand
INTEGER := unsigned integer, as defined by Rust
IDENT := valid identifier, as defined by Rust, except `_`
The generic route attribute is defined as:
generic-route := METHOD ',' 'path' '=' route
Typing Requirements
Every identifier that appears in a dynamic parameter (SINGLE_PARAM
or MULTI_PARAM
) must appear as an argument to the function. For
example, the following route requires the decorated function to have
the arguments foo
, baz
, msg
, rest
, and form
:
#[get("/<foo>/bar/<baz..>?<msg>&closed&<rest..>", data = "<form>")]
The type of each function argument corresponding to a dynamic
parameter is required to implement one of Rocket’s guard traits. The
exact trait that is required to be implemented depends on the kind
of dynamic parameter (SINGLE
or MULTI
) and where in the route
attribute the parameter appears. The table below summarizes trait
requirements:
position | kind | trait |
---|---|---|
path | <ident> | FromParam |
path | <ident..> | FromSegments |
query | <ident> | FromFormValue |
query | <ident..> | FromQuery |
data | <ident> | FromData |
The type of each function argument that does not have a
corresponding dynamic parameter is required to implement the
FromRequest
trait.
The return type of the decorated function must implement the
Responder
trait.
Semantics
The attribute generates three items:
-
A route
Handler
.The generated handler validates and generates all arguments for the generated function according to the trait that their type must implement. The order in which arguments are processed is:
-
Request guards from left to right.
If a request guard fails, the request is forwarded if the
Outcome
isForward
or failed if theOutcome
isFailure
. SeeFromRequest
Outcomes for further detail. -
Path and query parameters from left to right as declared in the function argument list.
If a path or query parameter guard fails, the request is forwarded.
-
Data parameter, if any.
If a data guard fails, the request is forwarded if the
Outcome
isForward
or failed if theOutcome
isFailure
. SeeFromData
Outcomes for further detail.
If all validation succeeds, the decorated function is called. The returned value is used to generate a
Response
via the type’sResponder
implementation. -
-
A static structure used by
routes!
to generate aRoute
.The static structure (and resulting
Route
) is populated with the name (the function’s name), path, query, rank, and format from the route attribute. The handler is set to the generated handler.