feat!: Replace hyper-specific interfaces with generic trait (#104)

Author: keelerm84

.github/workflows/ci.yml

@@ -1,11 +1,15 @@
 name: Run CI
 on:
   push:
-    branches: [main]
+    branches:
+      - "main"
+      - "feat/**"
     paths-ignore:
       - "**.md" # Do not need to run CI for markdown changes.
   pull_request:
-    branches: [main]
+    branches:
+      - "main"
+      - "feat/**"
     paths-ignore:
       - "**.md"
 

.github/workflows/release-please.yml

@@ -3,7 +3,8 @@ name: Run Release Please
 on:
   push:
     branches:
-      - main
+      - "main"
+      - "feat/**"
 
 jobs:
   release-package:

contract-tests/Cargo.toml

@@ -11,10 +11,11 @@ eventsource-client = { path = "../eventsource-client" }
 serde_json = { version = "1.0.39"}
 actix = { version = "0.13.1"}
 actix-web = { version = "4"}
-reqwest = { version = "0.11.6", default-features = false, features = ["json", "rustls-tls"] }
+reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls", "stream"] }
 env_logger = { version = "0.10.0" }
-hyper = { version = "0.14.19", features = ["client", "http1", "tcp"] }
 log = "0.4.6"
+http = "1.0"
+bytes = "1.5"
 
 [[bin]]
 name = "sse-test-api"

contract-tests/src/bin/sse-test-api/stream_entity.rs

@@ -1,15 +1,84 @@
 use actix_web::rt::task::JoinHandle;
-use futures::TryStreamExt;
+use futures::{StreamExt, TryStreamExt};
 use log::error;
 use std::{
     sync::{Arc, Mutex},
     time::Duration,
 };
 
 use eventsource_client as es;
+use eventsource_client::{ByteStream, HttpTransport, ResponseFuture, TransportError};
 
 use crate::{Config, EventType};
 
+// Simple reqwest-based transport implementation
+#[derive(Clone)]
+struct ReqwestTransport {
+    client: reqwest::Client,
+}
+
+impl ReqwestTransport {
+    fn new(timeout: Option<Duration>) -> Result<Self, reqwest::Error> {
+        let mut builder = reqwest::Client::builder();
+
+        if let Some(timeout) = timeout {
+            builder = builder.timeout(timeout);
+        }
+
+        let client = builder.build()?;
+        Ok(Self { client })
+    }
+}
+
+impl HttpTransport for ReqwestTransport {
+    fn request(&self, request: http::Request<Option<String>>) -> ResponseFuture {
+        let (parts, body_opt) = request.into_parts();
+
+        let mut req_builder = self
+            .client
+            .request(parts.method.clone(), parts.uri.to_string());
+
+        for (name, value) in parts.headers.iter() {
+            req_builder = req_builder.header(name, value);
+        }
+
+        if let Some(body) = body_opt {
+            req_builder = req_builder.body(body);
+        }
+
+        let req = match req_builder.build() {
+            Ok(r) => r,
+            Err(e) => return Box::pin(async move { Err(TransportError::new(e)) }),
+        };
+
+        let client = self.client.clone();
+
+        Box::pin(async move {
+            let resp = client.execute(req).await.map_err(TransportError::new)?;
+
+            let status = resp.status();
+            let headers = resp.headers().clone();
+
+            let byte_stream: ByteStream = Box::pin(
+                resp.bytes_stream()
+                    .map(|result| result.map_err(TransportError::new)),
+            );
+
+            let mut response_builder = http::Response::builder().status(status);
+
+            for (name, value) in headers.iter() {
+                response_builder = response_builder.header(name, value);
+            }
+
+            let response = response_builder
+                .body(byte_stream)
+                .map_err(TransportError::new)?;
+
+            Ok(response)
+        })
+    }
+}
+
 pub(crate) struct Inner {
     callback_counter: Mutex<i32>,
     callback_url: String,
@@ -102,9 +171,12 @@ impl Inner {
             reconnect_options = reconnect_options.delay(Duration::from_millis(delay_ms));
         }
 
-        if let Some(read_timeout_ms) = config.read_timeout_ms {
-            client_builder = client_builder.read_timeout(Duration::from_millis(read_timeout_ms));
-        }
+        // Create transport with timeout configuration
+        let timeout = config.read_timeout_ms.map(Duration::from_millis);
+        let transport = match ReqwestTransport::new(timeout) {
+            Ok(t) => t,
+            Err(e) => return Err(format!("Failed to create transport {:?}", e)),
+        };
 
         if let Some(last_event_id) = &config.last_event_id {
             client_builder = client_builder.last_event_id(last_event_id.clone());
@@ -128,7 +200,9 @@ impl Inner {
         }
 
         Ok(Box::new(
-            client_builder.reconnect(reconnect_options.build()).build(),
+            client_builder
+                .reconnect(reconnect_options.build())
+                .build_with_transport(transport),
         ))
     }
 }

eventsource-client/Cargo.toml

@@ -11,13 +11,12 @@ keywords = ["launchdarkly", "feature-flags", "feature-toggles", "eventsource", "
 exclude = ["CHANGELOG.md"]
 
 [dependencies]
+bytes = "1.5"
 futures = "0.3.21"
-hyper = { version = "0.14.19", features = ["client", "http1", "tcp"] }
-hyper-rustls = { version = "0.24.1", optional = true }
+http = "1.0"
 log = "0.4.6"
 pin-project = "1.0.10"
 tokio = { version = "1.17.0", features = ["time"] }
-hyper-timeout = "0.4.1"
 rand = "0.8.5"
 base64 = "0.22.1"
 
@@ -31,10 +30,6 @@ test-case = "3.2.1"
 proptest = "1.0.0"
 
 
-[features]
-default = ["rustls"]
-rustls = ["hyper-rustls", "hyper-rustls/http2"]
 
-[[example]]
-name = "tail"
-required-features = ["rustls"]
+[features]
+default = []

eventsource-client/README.md

@@ -4,41 +4,125 @@
 
 Client for the [Server-Sent Events] protocol (aka [EventSource]).
 
+This library focuses on the SSE protocol implementation. You provide the HTTP transport layer (hyper, reqwest, etc.), giving you full control over HTTP configuration like timeouts, TLS, and connection pooling.
+
 [Server-Sent Events]: https://html.spec.whatwg.org/multipage/server-sent-events.html
 [EventSource]: https://developer.mozilla.org/en-US/docs/Web/API/EventSource
 
 ## Requirements
 
-Requires tokio.
+* Tokio async runtime
+* An HTTP client library (hyper, reqwest, or custom)
+
+## Quick Start
+
+### 1. Add dependencies
 
-## Usage
+```toml
+[dependencies]
+eventsource-client = "0.17"
+reqwest = { version = "0.12", features = ["stream"] }  # or hyper v1
+futures = "0.3"
+tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
+```
+
+### 2. Implement HttpTransport
 
-Example that just prints the type of each event received:
+Use one of our example implementations:
 
 ```rust
-use eventsource_client as es;
+// See examples/reqwest_transport.rs for complete implementation
+use eventsource_client::{HttpTransport, ResponseFuture};
 
-let mut client = es::ClientBuilder::for_url("https://example.com/stream")?
-    .header("Authorization", "Basic username:password")?
-    .build();
+struct ReqwestTransport {
+    client: reqwest::Client,
+}
 
-client
-    .stream()
-    .map_ok(|event| println!("got event: {:?}", event))
-    .map_err(|err| eprintln!("error streaming events: {:?}", err));
+impl HttpTransport for ReqwestTransport {
+    fn request(&self, request: http::Request<()>) -> ResponseFuture {
+        // Convert request and call HTTP client
+        // See examples/ for full implementation
+    }
+}
 ```
 
-(Some boilerplate omitted for clarity; see [examples directory] for complete,
-working code.)
+### 3. Use the client
+
+```rust
+use eventsource_client::{ClientBuilder, SSE};
+use futures::TryStreamExt;
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Create HTTP transport
+    let transport = ReqwestTransport::new()?;
+
+    // Build SSE client
+    let client = ClientBuilder::for_url("https://example.com/stream")?
+        .header("Authorization", "Bearer token")?
+        .build_with_transport(transport);
+
+    // Stream events
+    let mut stream = client.stream();
+
+    while let Some(event) = stream.try_next().await? {
+        match event {
+            SSE::Event(evt) => println!("Event: {}", evt.event_type),
+            SSE::Comment(c) => println!("Comment: {}", c),
+            SSE::Connected(_) => println!("Connected!"),
+        }
+    }
+
+    Ok(())
+}
+```
 
-[examples directory]: https://github.com/launchdarkly/rust-eventsource-client/tree/main/eventsource-client/examples
 ## Features
 
-* tokio-based streaming client.
-* Supports setting custom headers on the HTTP request (e.g. for endpoints
-  requiring authorization).
-* Retry for failed connections.
-* Reconnection if connection is interrupted, with exponential backoff.
+* **Pluggable HTTP transport** - Use any HTTP client (hyper, reqwest, or custom)
+* **Tokio-based streaming** - Efficient async/await support
+* **Custom headers** - Full control over HTTP requests
+* **Automatic reconnection** - Configurable exponential backoff
+* **Retry logic** - Handle transient failures gracefully
+* **Redirect following** - Automatic handling of HTTP redirects
+* **Last-Event-ID** - Resume streams from last received event
+
+## Migration from v0.16
+
+If you're upgrading from v0.16 (which used hyper 0.14 internally), see [MIGRATION.md](MIGRATION.md) for a detailed migration guide.
+
+Key changes:
+- You must now provide an HTTP transport implementation
+- Removed `build()`, `build_http()`, and other hyper-specific methods
+- Use `build_with_transport(transport)` instead
+- Timeout configuration moved to your HTTP transport
+
+## Why Pluggable Transport?
+
+1. **Use latest HTTP clients** - Not locked to a specific HTTP library version
+2. **Full control** - Configure timeouts, TLS, proxies, etc. exactly as needed
+3. **Smaller library** - Focused on SSE protocol, not HTTP implementation
+4. **Flexibility** - Swap HTTP clients without changing SSE code
+
+## Architecture
+
+```
+┌─────────────────────────────────────┐
+│   Your Application                  │
+└─────────────┬───────────────────────┘
+              │
+              ▼
+┌─────────────────────────────────────┐
+│   eventsource-client                │
+│   (SSE Protocol Implementation)     │
+└─────────────┬───────────────────────┘
+              │ HttpTransport trait
+              ▼
+┌─────────────────────────────────────┐
+│   Your HTTP Client                  │
+│   (hyper, reqwest, custom, etc.)    │
+└─────────────────────────────────────┘
+```
 
 ## Stability