Make serde_yaml dependency optional

Fixes #152

Author: weiznich

crates/oas3/Cargo.toml

@@ -11,8 +11,9 @@ edition = { workspace = true }
 rust-version = { workspace = true }
 
 [features]
-default = ["validation"]
+default = ["validation", "yaml_spec"]
 validation = []
+yaml_spec = ["dep:serde_yaml"]
 
 [dependencies]
 derive_more = { workspace = true, features = ["display", "error", "from"] }
@@ -23,7 +24,7 @@ regex = { workspace = true }
 semver = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true }
-serde_yaml = { workspace = true }
+serde_yaml = { workspace = true, optional = true }
 url = { workspace = true, features = ["serde"] }
 
 [dev-dependencies]

crates/oas3/src/error.rs

@@ -15,6 +15,7 @@ pub enum Error {
 
     /// YAML error.
     #[display("YAML error")]
+    #[cfg(feature = "yaml_spec")]
     Yaml(serde_yaml::Error),
 
     /// JSON error.

crates/oas3/src/lib.rs

@@ -32,6 +32,8 @@ pub use self::{error::Error, spec::Spec};
 pub type OpenApiV3Spec = spec::Spec;
 
 /// Try deserializing an OpenAPI spec (YAML or JSON) from a file, giving the path.
+///
+/// If the `yaml` feature flag is disabled only `JSON` specs are supported
 pub fn from_path<P>(path: P) -> Result<OpenApiV3Spec, Error>
 where
     P: AsRef<Path>,
@@ -40,19 +42,38 @@ where
 }
 
 /// Try deserializing an OpenAPI spec (YAML or JSON) from a [`Read`] type.
+///
+/// If the `yaml` feature flag is disabled only `JSON` specs are supported
 pub fn from_reader<R>(read: R) -> Result<OpenApiV3Spec, Error>
 where
     R: Read,
 {
-    Ok(serde_yaml::from_reader::<R, OpenApiV3Spec>(read)?)
+    #[cfg(feature = "yaml_spec")]
+    {
+        Ok(serde_yaml::from_reader::<R, OpenApiV3Spec>(read)?)
+    }
+    #[cfg(not(feature = "yaml_spec"))]
+    {
+        Ok(serde_json::from_reader::<R, OpenApiV3Spec>(read)?)
+    }
 }
 
 /// Try deserializing an OpenAPI spec (YAML or JSON) from string.
+///
+/// If the `yaml` feature flag is disabled only `JSON` specs are supported
 pub fn from_str(val: impl AsRef<str>) -> Result<OpenApiV3Spec, Error> {
-    Ok(serde_yaml::from_str::<OpenApiV3Spec>(val.as_ref())?)
+    #[cfg(feature = "yaml_spec")]
+    {
+        Ok(serde_yaml::from_str::<OpenApiV3Spec>(val.as_ref())?)
+    }
+    #[cfg(not(feature = "yaml_spec"))]
+    {
+        Ok(serde_json::from_str::<OpenApiV3Spec>(val.as_ref())?)
+    }
 }
 
 /// Try serializing to a YAML string.
+#[cfg(feature = "yaml_spec")]
 pub fn to_yaml(spec: &OpenApiV3Spec) -> Result<String, Error> {
     Ok(serde_yaml::to_string(spec)?)
 }

crates/oas3/src/spec/spec_extensions.rs

@@ -5,6 +5,11 @@ use std::{
 
 use serde::{de, Deserializer, Serializer};
 
+#[cfg(feature = "yaml_spec")]
+type KeyType = serde_yaml::Value;
+#[cfg(not(feature = "yaml_spec"))]
+type KeyType = serde_json::Value;
+
 /// Deserializes fields of a map beginning with `x-`.
 pub(crate) fn deserialize<'de, D>(
     deserializer: D,
@@ -25,7 +30,7 @@ where
         where
             M: de::MapAccess<'de>,
         {
-            let mut map = HashMap::<serde_yaml::Value, serde_json::Value>::new();
+            let mut map = HashMap::<KeyType, serde_json::Value>::new();
 
             while let Some((key, value)) = access.next_entry()? {
                 map.insert(key, value);

crates/roast/Cargo.toml

@@ -17,7 +17,7 @@ derive_more = { workspace = true, features = ["display", "error", "from"] }
 futures-util = { workspace = true }
 http = { workspace = true }
 log = { workspace = true }
-oas3 = { workspace = true }
+oas3 = { workspace = true, default-features = false }
 once_cell = { workspace = true }
 prettytable-rs = { workspace = true }
 reqwest = { workspace = true, features = ["json"] }