Make yup-oauth2 optional

Cargo.toml

@@ -29,17 +29,18 @@ futures = "0.3"
 hex = "0.4"
 http = "0.2"
 hyper = "0.13"
-hyper-rustls = "0.20"
+hyper-rustls = { version = "0.20", optional = true }
 log = "0.4"
 opentelemetry = "0.8"
 prost = "0.6"
 prost-types = "0.6"
 rustls = "0.18"
 tonic = { version = "0.3.1", features = ["transport", "tls"] }
 tokio = { version = "0.2", optional = true }
-yup-oauth2 = "4.1"
+yup-oauth2 = { version = "4.1", optional = true }
 webpki-roots = "0.20"
 
 [features]
-default = []
+default = ["yup-authorizer"]
+yup-authorizer = ["hyper-rustls", "yup-oauth2"]
 tokio_adapter = ["tokio"]

src/lib.rs

@@ -36,11 +36,13 @@ use std::{
   },
   time::{Duration, Instant},
 };
+#[cfg(feature = "yup-oauth2")]
+use tonic::metadata::MetadataValue;
 use tonic::{
-  metadata::MetadataValue,
   transport::{Channel, ClientTlsConfig},
   Request,
 };
+#[cfg(feature = "yup-oauth2")]
 use yup_oauth2::authenticator::Authenticator;
 
 pub mod proto {
@@ -248,11 +250,13 @@ pub trait Authorizer: Sync + Send + 'static {
   async fn authorize<T: Send + Sync>(&self, request: &mut Request<T>) -> Result<(), Self::Error>;
 }
 
+#[cfg(feature = "yup-oauth2")]
 pub struct YupAuthorizer {
   authenticator: Authenticator<hyper_rustls::HttpsConnector<hyper::client::HttpConnector>>,
   project_name: String,
 }
 
+#[cfg(feature = "yup-oauth2")]
 impl YupAuthorizer {
   pub async fn new(
     credentials_path: impl AsRef<std::path::Path>,
@@ -272,6 +276,7 @@ impl YupAuthorizer {
   }
 }
 
+#[cfg(feature = "yup-oauth2")]
 #[async_trait]
 impl Authorizer for YupAuthorizer {
   type Error = Box<dyn std::error::Error + Send + Sync>;