Attribute Macro OpenApi

#[OpenApi]

Define an OpenAPI.

Macro parameters

These are attributes that can be added to the #[OpenApi] attribute.

Attribute	Description	Type	Optional
prefix_path	Define the prefix for all operation paths. May contain shared path parameters.	string	Y
tag	Define a tag for all operations. This must be the name of an in-scope variant of an enum which implements Tags	Tags	Y
response_header	Add an extra response header to all operations.	ExtraHeader	Y
request_header	Add an extra request header to all operations.	ExtraHeader	Y

Example

use poem_openapi::{OpenApi, Tags};
use poem_openapi::param::Path;
use poem_openapi::payload::PlainText;

#[derive(Tags)]
enum MyTags {
    V1
}

struct Api;

#[OpenApi(prefix_path = "/v1/:customer_id", tag = "MyTags::V1")]
impl Api {
    /// Greet the customer
    ///
    /// # Example
    /// 
    /// Call `/v1/1234/hello` to get the response `"Hello 1234!"`. 
    #[oai(path = "/hello", method = "get")]
    async fn hello(&self, customer_id: Path<String>) -> PlainText<String> {
        PlainText(format!("Hello {}!", customer_id.0))
    }
}

Operation parameters

Parameters that can be passed into the #[oai()] attribute above each operation function within an OpenApi.

Attribute	Description	Type	Optional
path	URI path optionally containing path parameters (e.g., “/:name/hello”)	string	N
method	HTTP method. The possible values are “get”, “post”, “put”, “delete”, “head”, “options”, “connect”, “patch”, “trace”.	string	N
deprecated	Operation deprecated	bool	Y
external_docs	Specify a external resource for extended documentation	string	Y
tag	Tag to use for an operation. Must be a variant of an enum which implements Tags	Tags	Y
operation_id	Unique string used to identify the operation.	string	Y
transform	Use a function to transform the API endpoint.	string	Y
response_header	Add an extra response header to the operation.	ExtraHeader	Y
request_header	Add an extra request header to all operations.	ExtraHeader	Y
actual_type	Specifies the actual response type	string	Y
code_samples	Code samples for the operation	object	Y
hidden	Hide this operation in the document	bool	Y

Example

use poem_openapi::{OpenApi, Tags};
use poem_openapi::param::Path;
use poem_openapi::payload::PlainText;

#[derive(Tags)]
enum MyTags {
    V1
}

struct Api;

#[OpenApi]
impl Api {
    /// Greet the customer
    ///
    /// # Example
    /// 
    /// Call `/v1/1234/hello` to get the response `"Hello 1234!"`. 
    #[oai(path = "/v1/:customer_id/hello", method = "get", tag = "MyTags::V1")]
    async fn hello(&self, customer_id: Path<String>) -> PlainText<String> {
        PlainText(format!("Hello {}!", customer_id.0))
    }
}

Operation argument parameters

Attribute	Description	Type	Optional
name	Parameter name	string	Y
deprecated	Argument deprecated	bool	Y
default	Default value	bool,string	Y
explode	When this is true, parameter values of type array or object generate separate parameters for each value of the array or key-value pair of the map.	bool	Y (default: true)
validator.multiple_of	The value of “multiple_of” MUST be a number, strictly greater than 0. A numeric instance is only valid if division by this value results in an integer.	number	Y
validator.maximum	The value of “maximum” MUST be a number, representing an upper limit for a numeric instance. If exclusive is true and instance is less than the provided value, or else if the instance is less than or exactly equal to the provided value.	{ value: <number>, exclusive: <bool>}	Y
validator.minimum	The value of “minimum” MUST be a number, representing a lower limit for a numeric instance. If exclusive is true and instance is greater than the provided value, or else if the instance is greater than or exactly equal to the provided value.	{ value: <number>, exclusive: <bool>}	Y
validator.max_length	The value of “max_length” MUST be a non-negative integer. A string instance is valid against this validator if its length is less than, or equal to, the value.	usize	Y
validator.min_length	The value of “min_length” MUST be a non-negative integer. The value of this validator MUST be an integer. This integer MUST be greater than, or equal to, 0.	usize	Y
validator.pattern	The value of “pattern” MUST be a string. This string SHOULD be a valid regular expression, according to the ECMA 262 regular expression dialect. A string instance is considered valid if the regular expression matches the instance successfully.	string	Y
validator.max_items	The value of “max_items” MUST be an integer. This integer MUST be greater than, or equal to, 0. An array instance is valid if its size is less than, or equal to, the value of this validator.	usize	Y
validator.min_items	The value of “min_items” MUST be an integer. This integer MUST be greater than, or equal to, 0. An array instance is valid if its size is greater than, or equal to, the value of this validator.	usize	Y
validator.unique_items	The value of “unique_items” MUST be an boolean. If this value is false, the instance validates successfully. If this value is true, the instance validates successfully if all of its elements are unique.	bool	Y
validator.max_properties	The value of this keyword MUST be a non-negative integer. An object instance is valid against “maxProperties” if its number of properties is less than, or equal to, the value of this keyword.	usize	Y
validator.min_properties	The value of this keyword MUST be a non-negative integer. An object instance is valid against “minProperties” if its number of properties is greater than, or equal to, the value of this keyword.	usize	Y

Examples

use poem_openapi::{
    param::Header,
    payload::{Json, PlainText},
    ApiRequest, Object, OpenApi, ApiResponse,
};

#[derive(Object)]
struct Pet {
    id: String,
    name: String,
}

#[derive(ApiRequest)]
enum CreatePetRequest {
    /// This request receives a pet in JSON format(application/json).
    CreateByJSON(Json<Pet>),
    /// This request receives a pet in text format(text/plain).
    CreateByPlainText(PlainText<String>),
}

#[derive(ApiResponse)]
enum CreatePetResponse {
    /// Returns when the pet is successfully created.
    #[oai(status = 200)]
    Ok,
    /// Returns when the pet already exists.
    #[oai(status = 409)]
    PetAlreadyExists,
}

struct PetApi;

#[OpenApi]
impl PetApi {
    /// Create a new pet.
    #[oai(path = "/pet", method = "post")]
    async fn create_pet(
        &self,
        #[oai(name = "TOKEN")] token: Header<String>,
        req: CreatePetRequest
    ) -> CreatePetResponse {
        todo!()
    }
}