OpenAPI Codegen Bug

README.md

There seems to be a bug in how oneOf code gets generated in OpenAPI >6.0.

The type gets generated as an empty struct instead of swagger::OneOf<A, B> as it was in 5.4

Makefile

generate-540:
	docker run --rm \
		-v $(PWD):/local openapitools/openapi-generator-cli:v5.4.0 generate \
		-i /local/test.yaml \
		--generator-name rust-server \
		--output /local/openapi \
		--global-property models,modelDocs=false,supportingFiles
	mv openapi/src/models.rs test-540.rs
	rm -rf openapi

generate-710:
	docker run --rm \
		-v $(PWD):/local openapitools/openapi-generator-cli:v7.1.0 generate \
		-i /local/test.yaml \
		--generator-name rust-server \
		--output /local/openapi \
		--global-property models,modelDocs=false,supportingFiles
	mv openapi/src/models.rs test-710.rs
	rm -rf openapi

generate-latest:
	docker run --rm \
		-v $(PWD):/local openapitools/openapi-generator-cli:latest generate \
		-i /local/test.yaml \
		--generator-name rust-server \
		--output /local/openapi \
		--global-property models,modelDocs=false,supportingFiles
	mv openapi/src/models.rs test-latest.rs
	rm -rf openapi

test-540.rs

#![allow(unused_qualifications)]

use crate::models;
#[cfg(any(feature = "client", feature = "server"))]
use crate::header;

#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize)]
#[cfg_attr(feature = "conversion", derive(frunk::LabelledGeneric))]
pub struct Test {
    #[serde(rename = "something")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something: Option<swagger::OneOf2<String,i32>>,

    #[serde(rename = "something_else")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something_else: Option<String>,

}

impl Test {
    pub fn new() -> Test {
        Test {
            something: None,
            something_else: None,
        }
    }
}

/// Converts the Test value to the Query Parameters representation (style=form, explode=false)
/// specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde serializer
impl std::string::ToString for Test {
    fn to_string(&self) -> String {
        let mut params: Vec<String> = vec![];
        // Skipping something in query parameter serialization


        if let Some(ref something_else) = self.something_else {
            params.push("something_else".to_string());
            params.push(something_else.to_string());
        }

        params.join(",").to_string()
    }
}

/// Converts Query Parameters representation (style=form, explode=false) to a Test value
/// as specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde deserializer
impl std::str::FromStr for Test {
    type Err = String;

    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
        #[derive(Default)]
        // An intermediate representation of the struct to use for parsing.
        struct IntermediateRep {
            pub something: Vec<swagger::OneOf2<String,i32>>,
            pub something_else: Vec<String>,
        }

        let mut intermediate_rep = IntermediateRep::default();

        // Parse into intermediate representation
        let mut string_iter = s.split(',').into_iter();
        let mut key_result = string_iter.next();

        while key_result.is_some() {
            let val = match string_iter.next() {
                Some(x) => x,
                None => return std::result::Result::Err("Missing value while parsing Test".to_string())
            };

            if let Some(key) = key_result {
                match key {
                    "something" => intermediate_rep.something.push(<swagger::OneOf2<String,i32> as std::str::FromStr>::from_str(val).map_err(|x| format!("{}", x))?),
                    "something_else" => intermediate_rep.something_else.push(<String as std::str::FromStr>::from_str(val).map_err(|x| format!("{}", x))?),
                    _ => return std::result::Result::Err("Unexpected key while parsing Test".to_string())
                }
            }

            // Get the next key
            key_result = string_iter.next();
        }

        // Use the intermediate representation to return the struct
        std::result::Result::Ok(Test {
            something: intermediate_rep.something.into_iter().next(),
            something_else: intermediate_rep.something_else.into_iter().next(),
        })
    }
}

// Methods for converting between header::IntoHeaderValue<Test> and hyper::header::HeaderValue

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<header::IntoHeaderValue<Test>> for hyper::header::HeaderValue {
    type Error = String;

    fn try_from(hdr_value: header::IntoHeaderValue<Test>) -> std::result::Result<Self, Self::Error> {
        let hdr_value = hdr_value.to_string();
        match hyper::header::HeaderValue::from_str(&hdr_value) {
             std::result::Result::Ok(value) => std::result::Result::Ok(value),
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Invalid header value for Test - value: {} is invalid {}",
                     hdr_value, e))
        }
    }
}

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<hyper::header::HeaderValue> for header::IntoHeaderValue<Test> {
    type Error = String;

    fn try_from(hdr_value: hyper::header::HeaderValue) -> std::result::Result<Self, Self::Error> {
        match hdr_value.to_str() {
             std::result::Result::Ok(value) => {
                    match <Test as std::str::FromStr>::from_str(value) {
                        std::result::Result::Ok(value) => std::result::Result::Ok(header::IntoHeaderValue(value)),
                        std::result::Result::Err(err) => std::result::Result::Err(
                            format!("Unable to convert header value '{}' into Test - {}",
                                value, err))
                    }
             },
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Unable to convert header: {:?} to string: {}",
                     hdr_value, e))
        }
    }
}

test-710.rs

#![allow(unused_qualifications)]

use validator::Validate;

use crate::models;
#[cfg(any(feature = "client", feature = "server"))]
use crate::header;

#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize, validator::Validate)]
#[cfg_attr(feature = "conversion", derive(frunk::LabelledGeneric))]
pub struct Test {
    #[serde(rename = "something")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something: Option<models::TestSomething>,

    #[serde(rename = "something_else")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something_else: Option<String>,

}


impl Test {
    #[allow(clippy::new_without_default)]
    pub fn new() -> Test {
        Test {
            something: None,
            something_else: None,
        }
    }
}

/// Converts the Test value to the Query Parameters representation (style=form, explode=false)
/// specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde serializer
impl std::string::ToString for Test {
    fn to_string(&self) -> String {
        let params: Vec<Option<String>> = vec![
            // Skipping something in query parameter serialization


            self.something_else.as_ref().map(|something_else| {
                vec![
                    "something_else".to_string(),
                    something_else.to_string(),
                ].join(",")
            }),

        ];

        params.into_iter().flatten().collect::<Vec<_>>().join(",")
    }
}

/// Converts Query Parameters representation (style=form, explode=false) to a Test value
/// as specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde deserializer
impl std::str::FromStr for Test {
    type Err = String;

    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
        /// An intermediate representation of the struct to use for parsing.
        #[derive(Default)]
        #[allow(dead_code)]
        struct IntermediateRep {
            pub something: Vec<models::TestSomething>,
            pub something_else: Vec<String>,
        }

        let mut intermediate_rep = IntermediateRep::default();

        // Parse into intermediate representation
        let mut string_iter = s.split(',');
        let mut key_result = string_iter.next();

        while key_result.is_some() {
            let val = match string_iter.next() {
                Some(x) => x,
                None => return std::result::Result::Err("Missing value while parsing Test".to_string())
            };

            if let Some(key) = key_result {
                #[allow(clippy::match_single_binding)]
                match key {
                    #[allow(clippy::redundant_clone)]
                    "something" => intermediate_rep.something.push(<models::TestSomething as std::str::FromStr>::from_str(val).map_err(|x| x.to_string())?),
                    #[allow(clippy::redundant_clone)]
                    "something_else" => intermediate_rep.something_else.push(<String as std::str::FromStr>::from_str(val).map_err(|x| x.to_string())?),
                    _ => return std::result::Result::Err("Unexpected key while parsing Test".to_string())
                }
            }

            // Get the next key
            key_result = string_iter.next();
        }

        // Use the intermediate representation to return the struct
        std::result::Result::Ok(Test {
            something: intermediate_rep.something.into_iter().next(),
            something_else: intermediate_rep.something_else.into_iter().next(),
        })
    }
}

// Methods for converting between header::IntoHeaderValue<Test> and hyper::header::HeaderValue

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<header::IntoHeaderValue<Test>> for hyper::header::HeaderValue {
    type Error = String;

    fn try_from(hdr_value: header::IntoHeaderValue<Test>) -> std::result::Result<Self, Self::Error> {
        let hdr_value = hdr_value.to_string();
        match hyper::header::HeaderValue::from_str(&hdr_value) {
             std::result::Result::Ok(value) => std::result::Result::Ok(value),
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Invalid header value for Test - value: {} is invalid {}",
                     hdr_value, e))
        }
    }
}

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<hyper::header::HeaderValue> for header::IntoHeaderValue<Test> {
    type Error = String;

    fn try_from(hdr_value: hyper::header::HeaderValue) -> std::result::Result<Self, Self::Error> {
        match hdr_value.to_str() {
             std::result::Result::Ok(value) => {
                    match <Test as std::str::FromStr>::from_str(value) {
                        std::result::Result::Ok(value) => std::result::Result::Ok(header::IntoHeaderValue(value)),
                        std::result::Result::Err(err) => std::result::Result::Err(
                            format!("Unable to convert header value '{}' into Test - {}",
                                value, err))
                    }
             },
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Unable to convert header: {:?} to string: {}",
                     hdr_value, e))
        }
    }
}


#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize, validator::Validate)]
#[cfg_attr(feature = "conversion", derive(frunk::LabelledGeneric))]
pub struct TestSomething {
}


impl TestSomething {
    #[allow(clippy::new_without_default)]
    pub fn new() -> TestSomething {
        TestSomething {
        }
    }
}

/// Converts the TestSomething value to the Query Parameters representation (style=form, explode=false)
/// specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde serializer
impl std::string::ToString for TestSomething {
    fn to_string(&self) -> String {
        let params: Vec<Option<String>> = vec![
        ];

        params.into_iter().flatten().collect::<Vec<_>>().join(",")
    }
}

/// Converts Query Parameters representation (style=form, explode=false) to a TestSomething value
/// as specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde deserializer
impl std::str::FromStr for TestSomething {
    type Err = String;

    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
        /// An intermediate representation of the struct to use for parsing.
        #[derive(Default)]
        #[allow(dead_code)]
        struct IntermediateRep {
        }

        let mut intermediate_rep = IntermediateRep::default();

        // Parse into intermediate representation
        let mut string_iter = s.split(',');
        let mut key_result = string_iter.next();

        while key_result.is_some() {
            let val = match string_iter.next() {
                Some(x) => x,
                None => return std::result::Result::Err("Missing value while parsing TestSomething".to_string())
            };

            if let Some(key) = key_result {
                #[allow(clippy::match_single_binding)]
                match key {
                    _ => return std::result::Result::Err("Unexpected key while parsing TestSomething".to_string())
                }
            }

            // Get the next key
            key_result = string_iter.next();
        }

        // Use the intermediate representation to return the struct
        std::result::Result::Ok(TestSomething {
        })
    }
}

// Methods for converting between header::IntoHeaderValue<TestSomething> and hyper::header::HeaderValue

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<header::IntoHeaderValue<TestSomething>> for hyper::header::HeaderValue {
    type Error = String;

    fn try_from(hdr_value: header::IntoHeaderValue<TestSomething>) -> std::result::Result<Self, Self::Error> {
        let hdr_value = hdr_value.to_string();
        match hyper::header::HeaderValue::from_str(&hdr_value) {
             std::result::Result::Ok(value) => std::result::Result::Ok(value),
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Invalid header value for TestSomething - value: {} is invalid {}",
                     hdr_value, e))
        }
    }
}

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<hyper::header::HeaderValue> for header::IntoHeaderValue<TestSomething> {
    type Error = String;

    fn try_from(hdr_value: hyper::header::HeaderValue) -> std::result::Result<Self, Self::Error> {
        match hdr_value.to_str() {
             std::result::Result::Ok(value) => {
                    match <TestSomething as std::str::FromStr>::from_str(value) {
                        std::result::Result::Ok(value) => std::result::Result::Ok(header::IntoHeaderValue(value)),
                        std::result::Result::Err(err) => std::result::Result::Err(
                            format!("Unable to convert header value '{}' into TestSomething - {}",
                                value, err))
                    }
             },
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Unable to convert header: {:?} to string: {}",
                     hdr_value, e))
        }
    }
}

test-latest.rs

#![allow(unused_qualifications)]

use validator::Validate;

use crate::models;
#[cfg(any(feature = "client", feature = "server"))]
use crate::header;

#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize, validator::Validate)]
#[cfg_attr(feature = "conversion", derive(frunk::LabelledGeneric))]
pub struct Test {
    #[serde(rename = "something")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something: Option<models::TestSomething>,

    #[serde(rename = "something_else")]
    #[serde(skip_serializing_if="Option::is_none")]
    pub something_else: Option<String>,

}


impl Test {
    #[allow(clippy::new_without_default)]
    pub fn new() -> Test {
        Test {
            something: None,
            something_else: None,
        }
    }
}

/// Converts the Test value to the Query Parameters representation (style=form, explode=false)
/// specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde serializer
impl std::string::ToString for Test {
    fn to_string(&self) -> String {
        let params: Vec<Option<String>> = vec![
            // Skipping something in query parameter serialization


            self.something_else.as_ref().map(|something_else| {
                [
                    "something_else".to_string(),
                    something_else.to_string(),
                ].join(",")
            }),

        ];

        params.into_iter().flatten().collect::<Vec<_>>().join(",")
    }
}

/// Converts Query Parameters representation (style=form, explode=false) to a Test value
/// as specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde deserializer
impl std::str::FromStr for Test {
    type Err = String;

    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
        /// An intermediate representation of the struct to use for parsing.
        #[derive(Default)]
        #[allow(dead_code)]
        struct IntermediateRep {
            pub something: Vec<models::TestSomething>,
            pub something_else: Vec<String>,
        }

        let mut intermediate_rep = IntermediateRep::default();

        // Parse into intermediate representation
        let mut string_iter = s.split(',');
        let mut key_result = string_iter.next();

        while key_result.is_some() {
            let val = match string_iter.next() {
                Some(x) => x,
                None => return std::result::Result::Err("Missing value while parsing Test".to_string())
            };

            if let Some(key) = key_result {
                #[allow(clippy::match_single_binding)]
                match key {
                    #[allow(clippy::redundant_clone)]
                    "something" => intermediate_rep.something.push(<models::TestSomething as std::str::FromStr>::from_str(val).map_err(|x| x.to_string())?),
                    #[allow(clippy::redundant_clone)]
                    "something_else" => intermediate_rep.something_else.push(<String as std::str::FromStr>::from_str(val).map_err(|x| x.to_string())?),
                    _ => return std::result::Result::Err("Unexpected key while parsing Test".to_string())
                }
            }

            // Get the next key
            key_result = string_iter.next();
        }

        // Use the intermediate representation to return the struct
        std::result::Result::Ok(Test {
            something: intermediate_rep.something.into_iter().next(),
            something_else: intermediate_rep.something_else.into_iter().next(),
        })
    }
}

// Methods for converting between header::IntoHeaderValue<Test> and hyper::header::HeaderValue

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<header::IntoHeaderValue<Test>> for hyper::header::HeaderValue {
    type Error = String;

    fn try_from(hdr_value: header::IntoHeaderValue<Test>) -> std::result::Result<Self, Self::Error> {
        let hdr_value = hdr_value.to_string();
        match hyper::header::HeaderValue::from_str(&hdr_value) {
             std::result::Result::Ok(value) => std::result::Result::Ok(value),
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Invalid header value for Test - value: {} is invalid {}",
                     hdr_value, e))
        }
    }
}

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<hyper::header::HeaderValue> for header::IntoHeaderValue<Test> {
    type Error = String;

    fn try_from(hdr_value: hyper::header::HeaderValue) -> std::result::Result<Self, Self::Error> {
        match hdr_value.to_str() {
             std::result::Result::Ok(value) => {
                    match <Test as std::str::FromStr>::from_str(value) {
                        std::result::Result::Ok(value) => std::result::Result::Ok(header::IntoHeaderValue(value)),
                        std::result::Result::Err(err) => std::result::Result::Err(
                            format!("Unable to convert header value '{}' into Test - {}",
                                value, err))
                    }
             },
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Unable to convert header: {:?} to string: {}",
                     hdr_value, e))
        }
    }
}


#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize, validator::Validate)]
#[cfg_attr(feature = "conversion", derive(frunk::LabelledGeneric))]
pub struct TestSomething {
}


impl TestSomething {
    #[allow(clippy::new_without_default)]
    pub fn new() -> TestSomething {
        TestSomething {
        }
    }
}

/// Converts the TestSomething value to the Query Parameters representation (style=form, explode=false)
/// specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde serializer
impl std::string::ToString for TestSomething {
    fn to_string(&self) -> String {
        let params: Vec<Option<String>> = vec![
        ];

        params.into_iter().flatten().collect::<Vec<_>>().join(",")
    }
}

/// Converts Query Parameters representation (style=form, explode=false) to a TestSomething value
/// as specified in https://swagger.io/docs/specification/serialization/
/// Should be implemented in a serde deserializer
impl std::str::FromStr for TestSomething {
    type Err = String;

    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
        /// An intermediate representation of the struct to use for parsing.
        #[derive(Default)]
        #[allow(dead_code)]
        struct IntermediateRep {
        }

        let mut intermediate_rep = IntermediateRep::default();

        // Parse into intermediate representation
        let mut string_iter = s.split(',');
        let mut key_result = string_iter.next();

        while key_result.is_some() {
            let val = match string_iter.next() {
                Some(x) => x,
                None => return std::result::Result::Err("Missing value while parsing TestSomething".to_string())
            };

            if let Some(key) = key_result {
                #[allow(clippy::match_single_binding)]
                match key {
                    _ => return std::result::Result::Err("Unexpected key while parsing TestSomething".to_string())
                }
            }

            // Get the next key
            key_result = string_iter.next();
        }

        // Use the intermediate representation to return the struct
        std::result::Result::Ok(TestSomething {
        })
    }
}

// Methods for converting between header::IntoHeaderValue<TestSomething> and hyper::header::HeaderValue

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<header::IntoHeaderValue<TestSomething>> for hyper::header::HeaderValue {
    type Error = String;

    fn try_from(hdr_value: header::IntoHeaderValue<TestSomething>) -> std::result::Result<Self, Self::Error> {
        let hdr_value = hdr_value.to_string();
        match hyper::header::HeaderValue::from_str(&hdr_value) {
             std::result::Result::Ok(value) => std::result::Result::Ok(value),
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Invalid header value for TestSomething - value: {} is invalid {}",
                     hdr_value, e))
        }
    }
}

#[cfg(any(feature = "client", feature = "server"))]
impl std::convert::TryFrom<hyper::header::HeaderValue> for header::IntoHeaderValue<TestSomething> {
    type Error = String;

    fn try_from(hdr_value: hyper::header::HeaderValue) -> std::result::Result<Self, Self::Error> {
        match hdr_value.to_str() {
             std::result::Result::Ok(value) => {
                    match <TestSomething as std::str::FromStr>::from_str(value) {
                        std::result::Result::Ok(value) => std::result::Result::Ok(header::IntoHeaderValue(value)),
                        std::result::Result::Err(err) => std::result::Result::Err(
                            format!("Unable to convert header value '{}' into TestSomething - {}",
                                value, err))
                    }
             },
             std::result::Result::Err(e) => std::result::Result::Err(
                 format!("Unable to convert header: {:?} to string: {}",
                     hdr_value, e))
        }
    }
}

test.yaml

openapi: 3.0.3

info:
  title: Test
  version: "0.2"

paths:
  /a:
    post:
      summary: Test
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Test'
      responses:
        200:
          description: Ok

components:
  schemas:
    Test:
      type: object
      properties:
        something:
          oneOf:
            - type: string
            - type: integer
        something_else:
          type: string