Support deprecated API endpoints in reqwest-based Rust clients (#22131)

Previously, if an API endpoint was marked deprecated, this fact was not
reflected in the generated Rust clients using the reqwest library. We
want to know exactly when our client code is using a deprecated endpoint,
so marking the corresponding functions with the `#[deprecatd]` attribute
would be very helpful. Uses of the endpoint would then be picked up by
linters so that we can react.

This adds a line to the template which marks functions generated from
deprecated endpoints with the `#[deprecated]` attribute.

This does not touch any of the other client generators for Rust or any
other language, since they are out of scope for our needs.

Co-authored-by: Bradford Hovinen <[email protected]>

Author: hovinen

modules/openapi-generator/src/main/resources/rust/reqwest/api.mustache

@@ -99,6 +99,9 @@ pub enum {{{operationIdCamelCase}}}Error {
 {{#notes}}
 /// {{{.}}}
 {{/notes}}
+{{#isDeprecated}}
+#[deprecated]
+{{/isDeprecated}}
 {{#vendorExtensions.x-group-parameters}}
 pub {{#supportAsync}}async {{/supportAsync}}fn {{{operationId}}}(configuration: &configuration::Configuration{{#allParams}}{{#-first}}, {{!
 ### Params

samples/client/petstore/rust/reqwest/petstore-async-middleware/src/apis/pet_api.rs

@@ -359,6 +359,7 @@ pub async fn find_pets_by_status(configuration: &configuration::Configuration, p
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub async fn find_pets_by_tags(configuration: &configuration::Configuration, params: FindPetsByTagsParams) -> Result<ResponseContent<FindPetsByTagsSuccess>, Error<FindPetsByTagsError>> {
 
     let uri_str = format!("{}/pet/findByTags", configuration.base_path);

samples/client/petstore/rust/reqwest/petstore-async-tokensource/src/apis/pet_api.rs

@@ -365,6 +365,7 @@ pub async fn find_pets_by_status(configuration: &configuration::Configuration, p
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub async fn find_pets_by_tags(configuration: &configuration::Configuration, params: FindPetsByTagsParams) -> Result<ResponseContent<FindPetsByTagsSuccess>, Error<FindPetsByTagsError>> {
 
     let uri_str = format!("{}/pet/findByTags", configuration.base_path);

samples/client/petstore/rust/reqwest/petstore-async/src/apis/pet_api.rs

@@ -359,6 +359,7 @@ pub async fn find_pets_by_status(configuration: &configuration::Configuration, p
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub async fn find_pets_by_tags(configuration: &configuration::Configuration, params: FindPetsByTagsParams) -> Result<ResponseContent<FindPetsByTagsSuccess>, Error<FindPetsByTagsError>> {
 
     let uri_str = format!("{}/pet/findByTags", configuration.base_path);

samples/client/petstore/rust/reqwest/petstore-avoid-box/src/apis/pet_api.rs

@@ -359,6 +359,7 @@ pub async fn find_pets_by_status(configuration: &configuration::Configuration, p
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub async fn find_pets_by_tags(configuration: &configuration::Configuration, params: FindPetsByTagsParams) -> Result<ResponseContent<FindPetsByTagsSuccess>, Error<FindPetsByTagsError>> {
 
     let uri_str = format!("{}/pet/findByTags", configuration.base_path);

samples/client/petstore/rust/reqwest/petstore-awsv4signature/src/apis/pet_api.rs

@@ -263,6 +263,7 @@ pub fn find_pets_by_status(configuration: &configuration::Configuration, status:
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub fn find_pets_by_tags(configuration: &configuration::Configuration, tags: Vec<String>) -> Result<Vec<models::Pet>, Error<FindPetsByTagsError>> {
     // add a prefix to parameters to efficiently prevent name collisions
     let p_query_tags = tags;

samples/client/petstore/rust/reqwest/petstore-model-name-prefix/src/apis/pet_api.rs

@@ -224,6 +224,7 @@ pub fn find_pets_by_status(configuration: &configuration::Configuration, status:
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub fn find_pets_by_tags(configuration: &configuration::Configuration, tags: Vec<String>) -> Result<Vec<models::FooPet>, Error<FindPetsByTagsError>> {
     // add a prefix to parameters to efficiently prevent name collisions
     let p_query_tags = tags;

samples/client/petstore/rust/reqwest/petstore/src/apis/pet_api.rs

@@ -224,6 +224,7 @@ pub fn find_pets_by_status(configuration: &configuration::Configuration, status:
 }
 
 /// Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+#[deprecated]
 pub fn find_pets_by_tags(configuration: &configuration::Configuration, tags: Vec<String>) -> Result<Vec<models::Pet>, Error<FindPetsByTagsError>> {
     // add a prefix to parameters to efficiently prevent name collisions
     let p_query_tags = tags;