headers too

src/lib.rs

@@ -11,11 +11,23 @@ mod metrics;
 #[worker::send]
 pub async fn do_fetch(
     url: String,
+    headers: String,
     data: Option<JsValue>,
 ) -> Result<Response> {
+    let mut http_headers = Headers::new();
+    // split headers by command, and then by =
+    for header in headers.split(",") {
+        let parts: Vec<&str> = header.split("=").collect();
+        if parts.len() == 2 {
+            let key = parts[0].trim();
+            let value = parts[1].trim();
+            http_headers.set(key, value).expect("failed to construct header");
+        }
+    }
+
     let mut init = RequestInit::new();
     init.method = Method::Post;
-    init.with_body(data);
+    init.with_body(data).with_headers(http_headers);
     Fetch::Request(Request::new_with_init(url.as_str(), &init)?)
         .send()
         .await
@@ -27,6 +39,10 @@ async fn main(_req: Request, env: Env, _ctx: Context) -> Result<Response> {
     let cloudflare_api_url = env.var("CLOUDFLARE_API_URL")?.to_string();
     let cloudflare_api_key = env.var("CLOUDFLARE_API_KEY")?.to_string();
     let cloudflare_account_id = env.var("CLOUDFLARE_ACCOUNT_ID")?.to_string();
+    let otlp_headers = match env.var("OTLP_HEADERS") {
+        Ok(val) => val.to_string(),
+        Err(_) => String::from(""),
+    };
 
     let end = chrono::Utc::now();
     let start = end - chrono::Duration::minutes(1);
@@ -61,6 +77,6 @@ async fn main(_req: Request, env: Env, _ctx: Context) -> Result<Response> {
     };
     let metrics = MetricsData::from(&mut resource_metrics);
     let metrics_json = serde_json::to_string(&metrics).unwrap();
-    let response = do_fetch(metrics_url, Some(JsValue::from_str(&metrics_json)).into()).await?;
+    let response = do_fetch(metrics_url, otlp_headers, Some(JsValue::from_str(&metrics_json)).into()).await?;
     return Ok(response);
 }

wrangler.toml

@@ -15,6 +15,7 @@ build = { command = "cargo install -q worker-build && worker-build --dev" }
 
 [env.dev.vars]
 METRICS_URL = "http://collector:4318/v1/metrics"
+OTLP_HEADERS = "Authorization=Basic <base64 instanceID:token>"
 CLOUDFLARE_API_URL = "https://api.cloudflare.com/client/v4/graphql"
 CLOUDFLARE_API_KEY = "fake"
 CLOUDFLARE_ACCOUNT_ID = "1234"