From 7ed98c82e820899cd0dd57cd2f0df62a826a252a Mon Sep 17 00:00:00 2001
From: msrd0 <1182023-msrd0@users.noreply.gitlab.com>
Date: Wed, 24 Feb 2021 18:53:44 +0000
Subject: [PATCH] OpenAPI: Key Schema for HashMap's

---
 CHANGELOG.md         |  1 +
 src/openapi/types.rs | 25 ++++++++++++++++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 372120c..3349897 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  - If not enabling the `openapi` feature, `without-openapi` has to be enabled
  - The endpoint macro attributes (`read`, `create`, ...) no longer take the resource ident and reject all unknown attributes ([!18])
  - The `ResourceResult` trait has been split into `ResourceResult` and `ResourceResultSchema`
+ - `HashMap`'s keys are included in the generated OpenAPI spec (they defaulted to `type: string` previously)
 
 ### Removed
  - All pre-defined methods (`read`, `create`, ...) from our router extensions ([!18])
diff --git a/src/openapi/types.rs b/src/openapi/types.rs
index e15a6b5..18f5be6 100644
--- a/src/openapi/types.rs
+++ b/src/openapi/types.rs
@@ -344,10 +344,24 @@ impl<T: OpenapiType, S: BuildHasher> OpenapiType for HashSet<T, S> {
 	}
 }
 
-impl<K, T: OpenapiType, S: BuildHasher> OpenapiType for HashMap<K, T, S> {
+impl<K: OpenapiType, T: OpenapiType, S: BuildHasher> OpenapiType for HashMap<K, T, S> {
 	fn schema() -> OpenapiSchema {
+		let key_schema = K::schema();
+		let mut dependencies = key_schema.dependencies.clone();
+
+		let keys = match key_schema.name.clone() {
+			Some(name) => {
+				let reference = Reference {
+					reference: format!("#/components/schemas/{}", name)
+				};
+				dependencies.insert(name, key_schema);
+				reference
+			},
+			None => Item(Box::new(key_schema.into_schema()))
+		};
+
 		let schema = T::schema();
-		let mut dependencies = schema.dependencies.clone();
+		dependencies.extend(schema.dependencies.iter().map(|(k, v)| (k.clone(), v.clone())));
 
 		let items = Box::new(match schema.name.clone() {
 			Some(name) => {
@@ -360,10 +374,15 @@ impl<K, T: OpenapiType, S: BuildHasher> OpenapiType for HashMap<K, T, S> {
 			None => Item(schema.into_schema())
 		});
 
+		let mut properties = IndexMap::new();
+		properties.insert("default".to_owned(), keys);
+
 		OpenapiSchema {
 			nullable: false,
 			name: None,
 			schema: SchemaKind::Type(Type::Object(ObjectType {
+				properties,
+				required: vec!["default".to_owned()],
 				additional_properties: Some(AdditionalProperties::Schema(items)),
 				..Default::default()
 			})),
@@ -453,6 +472,6 @@ mod test {
 	assert_schema!(Vec<String> => r#"{"type":"array","items":{"type":"string"}}"#);
 	assert_schema!(BTreeSet<String> => r#"{"type":"array","items":{"type":"string"}}"#);
 	assert_schema!(HashSet<String> => r#"{"type":"array","items":{"type":"string"}}"#);
-	assert_schema!(HashMap<String, String> => r#"{"type":"object","additionalProperties":{"type":"string"}}"#);
+	assert_schema!(HashMap<i64, String> => r#"{"type":"object","properties":{"default":{"type":"integer","format":"int64"}},"required":["default"],"additionalProperties":{"type":"string"}}"#);
 	assert_schema!(Value => r#"{"nullable":true}"#);
 }