Remove isahc support

.cspell.json

@@ -37,7 +37,6 @@
         "Dirkjan",
         "EPYC",
         "hasher",
-        "isahc",
         "Isobel",
         "jaegertracing",
         "Kühle",

Cargo.toml

@@ -19,13 +19,13 @@ debug = 1
 async-std = "1.10"
 async-trait = "0.1"
 bytes = "1"
+cc = "=1.0.105" # pinning version supporting rustc 1.65
 criterion = "0.5"
 futures-core = "0.3"
 futures-executor = "0.3"
 futures-util = { version = "0.3", default-features = false }
 hyper = { version = "0.14", default-features = false }
 http = { version = "0.2", default-features = false }
-isahc = { version = "1.4", default-features = false }
 log = "0.4.21"
 once_cell = "1.13"
 ordered-float = "4.0"

opentelemetry-http/CHANGELOG.md

@@ -3,6 +3,7 @@
 ## vNext
 
 - **Breaking** Correct the misspelling of "webkpi" to "webpki" in features [#1842](https://github.com/open-telemetry/opentelemetry-rust/pull/1842)
+- **Breaking** Remove support for the `isahc` HTTP client [#1924](https://github.com/open-telemetry/opentelemetry-rust/pull/1924)
 
 ## v0.12.0
 

opentelemetry-http/Cargo.toml

@@ -18,7 +18,6 @@ async-trait = { workspace = true }
 bytes = { workspace = true }
 http = { workspace = true }
 hyper = { workspace = true, features = ["http2", "client", "tcp"], optional = true }
-isahc = { workspace = true, optional = true }
 opentelemetry = { version = "0.23", path = "../opentelemetry", features = ["trace"] }
 reqwest = { workspace = true, features = ["blocking"], optional = true }
 tokio = { workspace = true, features = ["time"], optional = true }

opentelemetry-http/src/lib.rs

@@ -99,32 +99,6 @@ mod reqwest {
     }
 }
 
-#[cfg(feature = "isahc")]
-mod isahc {
-    use crate::ResponseExt;
-
-    use super::{async_trait, Bytes, HttpClient, HttpError, Request, Response};
-    use isahc::AsyncReadResponseExt;
-    use std::convert::TryInto as _;
-
-    #[async_trait]
-    impl HttpClient for isahc::HttpClient {
-        async fn send(&self, request: Request<Vec<u8>>) -> Result<Response<Bytes>, HttpError> {
-            let mut response = self.send_async(request).await?;
-            let mut bytes = Vec::with_capacity(response.body().len().unwrap_or(0).try_into()?);
-            response.copy_to(&mut bytes).await?;
-
-            let headers = std::mem::take(response.headers_mut());
-            let mut http_response = Response::builder()
-                .status(response.status().as_u16())
-                .body(bytes.into())?;
-            *http_response.headers_mut() = headers;
-
-            Ok(http_response.error_for_status()?)
-        }
-    }
-}
-
 #[cfg(feature = "hyper")]
 pub mod hyper {
     use crate::ResponseExt;

opentelemetry/Cargo.toml

@@ -30,6 +30,11 @@ thiserror = { workspace = true }
 [target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
 js-sys = "0.3.63"
 
+# This cfg can't ever be enabled but cargo will respect it anyway.
+# Meaning we can use this to pin unused transitive dependencies.
+[target.'cfg(any())'.dependencies]
+cc = { workspace = true }
+
 [features]
 default = ["trace", "metrics", "logs"]
 trace = ["pin-project-lite"]