update grpc-http example to autometrics 2.0 (#182)

* update grpc-http example to autometrics 2.0

* update name of example to follow pattern of other examples

* install protoc

.github/workflows/ci.yml

@@ -35,13 +35,17 @@ jobs:
       # Build the crate using the other optional features
       - run: cargo build --features=metrics-0_21,custom-objective-percentile,custom-objective-latency
 
+      # Install protoc for the examples
+      - uses: arduino/setup-protoc@v3
+
       # Compile the examples
       - run: cargo build --package example-actix-web
       - run: cargo build --package example-axum
       - run: cargo build --package example-custom-metrics
       - run: cargo build --package example-exemplars-tracing
       - run: cargo build --package example-exemplars-tracing-opentelemetry
       - run: cargo build --package example-full-api
+      - run: cargo build --package example-grpc-http
       - run: cargo build --package example-opentelemetry-push
 
 

examples/grpc-http/Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "grpc-http"
+name = "example-grpc-http"
 version = "0.0.0"
 publish = false
 edition = "2021"

examples/grpc-http/src/main.rs

@@ -1,6 +1,7 @@
 use std::net::SocketAddr;
 use tonic::transport::Server as TonicServer;
 use warp::Filter;
+use warp::http::StatusCode;
 
 use autometrics::prometheus_exporter;
 use server::MyJobRunner;
@@ -52,7 +53,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     // Build http /metrics endpoint
     let routes = warp::get()
         .and(warp::path("metrics"))
-        .map(|| prometheus_exporter::encode_http_response());
+        .map(|| prometheus_exporter::encode_to_string().map_err(|_| StatusCode::INTERNAL_SERVER_ERROR));
 
     // Build http web server
     let (_, web_server) =