Merge pull request #162 from emit-rs/docs/zipkin-prom-examples

Include the examples for zipkin and prometheus

Cargo.toml

@@ -15,7 +15,9 @@ members = [
     "examples/common_patterns",
     "examples/opentelemetry/direct_otlp",
     "examples/opentelemetry/via_sdk",
-    "test/ui",
+    "examples/trace_zipkin",
+    "examples/metric_prometheus",
+    "test/ui", "examples/trace_zipkin", "examples/metric_prometheus",
 ]
 
 [package]

README.md

@@ -59,6 +59,8 @@ fn greet(user: &str) {
 
 ![An example trace produced by `emit` in Zipkin](https://github.com/emit-rs/emit/blob/main/asset/trace-zipkin.png?raw=true)
 
+The above screenshot was generated by [this example application](https://github.com/emit-rs/emit/tree/main/examples/trace_zipkin).
+
 See [the guide](https://emit-rs.io/producing-events/tracing.html) for details.
 
 ## Metrics
@@ -67,4 +69,6 @@ See [the guide](https://emit-rs.io/producing-events/tracing.html) for details.
 
 ![An example metric produced by `emit` in Prometheus](https://github.com/emit-rs/emit/blob/main/asset/metric-prometheus.png?raw=true)
 
+The above screenshot was generated by [this example application](https://github.com/emit-rs/emit/tree/main/examples/metric_prometheus).
+
 See [the guide](https://emit-rs.io/producing-events/metrics.html) for details.

book/src/producing-events/metrics.md

@@ -40,4 +40,4 @@ Event {
 
 ![an example metric in Prometheus](../asset/metric-prometheus.png)
 
-_An example metric produced by `emit` in Prometheus_
+_A metric produced by [this example application](https://github.com/emit-rs/emit/tree/main/examples/metric_prometheus) in Prometheus._

book/src/producing-events/tracing.md

@@ -63,4 +63,4 @@ The level of a span may also depend on its execution. See [Fallible functions](.
 
 ![an example trace in Zipkin](../asset/trace-zipkin.png)
 
-_An example trace produced by `emit` in Zipkin_
+_A trace produced by [this example application](https://github.com/emit-rs/emit/tree/main/examples/trace_zipkin) in Zipkin._

examples/metric_prometheus/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "emit_example_metric_prometheus"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[dependencies.emit]
+version = "0.11.0-alpha.21"
+path = "../../"
+
+[dependencies.emit_otlp]
+version = "0.11.0-alpha.21"
+path = "../../emitter/otlp"
+
+[dependencies.rand]
+version = "0.8"

examples/metric_prometheus/src/main.rs

@@ -0,0 +1,34 @@
+/*!
+An example of emitting metrics to Prometheus.
+
+Prometheus has direct support for OTLP: https://prometheus.io/docs/guides/opentelemetry/
+*/
+
+use rand::Rng;
+
+fn main() {
+    let rt = emit::setup()
+        .emit_to(
+            emit_otlp::new()
+                .resource(emit::props! {
+                    #[emit::key("service.name")]
+                    service_name: "emit-sample",
+                })
+                .metrics(emit_otlp::metrics_http_proto(
+                    "http://localhost:9090/api/v1/otlp/v1/metrics",
+                ))
+                .spawn(),
+        )
+        .init();
+
+    let mut bytes_written = 0usize;
+    for _ in 0..60 {
+        bytes_written += rand::thread_rng().gen_range(0..750);
+
+        emit::emit!(evt: emit::Metric::new(emit::pkg!(), "bytes_written", "count", emit::clock().now(), bytes_written, emit::Empty));
+
+        std::thread::sleep(std::time::Duration::from_secs(1));
+    }
+
+    rt.blocking_flush(std::time::Duration::from_secs(5));
+}

examples/trace_zipkin/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "emit_example_trace_zipkin"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[dependencies.emit]
+version = "0.11.0-alpha.21"
+path = "../../"
+
+[dependencies.emit_otlp]
+version = "0.11.0-alpha.21"
+path = "../../emitter/otlp"

examples/trace_zipkin/src/main.rs

@@ -0,0 +1,72 @@
+/*!
+An example of emitting traces to Zipkin.
+
+You can emit traces as OTLP to the OpenTelemetry Collector, and forward from there to Zipkin.
+Here's an example Collector configuration that does this:
+
+```yaml
+receivers:
+  otlp:
+    protocols:
+      http:
+        endpoint: 0.0.0.0:4319
+
+exporters:
+  zipkin:
+    endpoint: "http://localhost:9411/api/v2/spans"
+    format: proto
+    default_service_name: emit-sample
+
+service:
+  pipelines:
+    traces:
+      receivers: [otlp]
+      exporters: [zipkin]
+```
+*/
+
+fn main() {
+    let rt = emit::setup()
+        .emit_to(
+            emit_otlp::new()
+                .resource(emit::props! {
+                    #[emit::key("service.name")]
+                    service_name: "emit-sample",
+                })
+                .traces(emit_otlp::traces_http_proto(
+                    "http://localhost:4319/v1/traces",
+                ))
+                .spawn(),
+        )
+        .init();
+
+    let _ = add("1", "3");
+
+    rt.blocking_flush(std::time::Duration::from_secs(5));
+}
+
+#[emit::span(err: err_as_ref, "add {a} and {b}")]
+fn add(a: &str, b: &str) -> Result<String, Error> {
+    let a = parse(a)?;
+    let b = parse(b)?;
+
+    let r = a + b;
+
+    Ok(format(r))
+}
+
+#[emit::span(err: err_as_ref, "parse {n}")]
+fn parse(n: &str) -> Result<i32, Error> {
+    Ok(n.parse()?)
+}
+
+#[emit::span("format {n}")]
+fn format(n: i32) -> String {
+    n.to_string()
+}
+
+type Error = Box<dyn std::error::Error + 'static>;
+
+fn err_as_ref(err: &Error) -> &(dyn std::error::Error + 'static) {
+    &**err
+}