feat(worker): add tracing to bucket, when parent context is present (#9)

.gitignore

@@ -1,3 +1,4 @@
 node_modules
 dist
 coverage
+.dev.vars*

package.json

@@ -5,7 +5,7 @@
   "main": "src/worker.js",
   "type": "module",
   "scripts": {
-    "build": "esbuild src/worker.js --bundle --format=esm --outfile=dist/worker.mjs",
+    "build": "esbuild src/worker.js --bundle --format=esm --external:node:buffer --external:node:events --external:node:async_hooks --outfile=dist/worker.mjs",
     "lint": "standard",
     "test": "npm run build && entail"
   },
@@ -25,8 +25,12 @@
     "uint8arrays": "^5.1.0"
   },
   "dependencies": {
+    "@microlabs/otel-cf-workers": "1.0.0-rc.49",
+    "@opentelemetry/api": "^1.9.0",
+    "@opentelemetry/sdk-trace-base": "^1.30.0",
     "@web3-storage/gateway-lib": "^5.0.1",
-    "@web3-storage/public-bucket": "^1.2.0"
+    "@web3-storage/public-bucket": "^1.2.0",
+    "typescript": "^5.7.2"
   },
   "repository": {
     "type": "git",

src/tracebucket.js

@@ -0,0 +1,67 @@
+// eslint-disable-next-line
+import * as BucketAPI from '@web3-storage/public-bucket'
+import { trace, context, SpanStatusCode } from '@opentelemetry/api'
+
+/**
+ * @template {unknown[]} A
+ * @template {*} T
+ * @template {*} This
+ * @param {string} spanName
+ * @param {(this: This, ...args: A) => Promise<T>} fn
+ * @param {This} [thisParam]
+ */
+const withSimpleSpan = (spanName, fn, thisParam) =>
+  /**
+   * @param {A} args
+  */
+  async (...args) => {
+    const tracer = trace.getTracer('public-r2-bucket')
+    const span = tracer.startSpan(spanName)
+    const ctx = trace.setSpan(context.active(), span)
+
+    try {
+      const result = await context.with(ctx, fn, thisParam, ...args)
+      span.setStatus({ code: SpanStatusCode.OK })
+      span.end()
+      return result
+    } catch (err) {
+      if (err instanceof Error) {
+        span.setStatus({
+          code: SpanStatusCode.ERROR,
+          message: err.message
+        })
+      } else {
+        span.setStatus({
+          code: SpanStatusCode.ERROR
+        })
+      }
+      span.end()
+      throw err
+    }
+  }
+
+/** @implements {BucketAPI.Bucket} */
+export class TraceBucket {
+  #bucket
+
+  /**
+   *
+   * @param {BucketAPI.Bucket} bucket
+   */
+  constructor (bucket) {
+    this.#bucket = bucket
+  }
+
+  /** @param {string} key */
+  head (key) {
+    return withSimpleSpan('bucket.head', this.#bucket.head, this.#bucket)(key)
+  }
+
+  /**
+   * @param {string} key
+   * @param {BucketAPI.GetOptions} [options]
+   */
+  get (key, options) {
+    return withSimpleSpan('bucket.get', this.#bucket.get, this.#bucket)(key, options)
+  }
+}

src/worker.d.ts

@@ -1,9 +1,12 @@
 import { R2Bucket } from '@cloudflare/workers-types'
+import { Environment as MiddlewareEnvironment } from '@web3-storage/gateway-lib'
 
 export { R2Bucket }
 
-export interface Environment {
+export interface Environment extends MiddlewareEnvironment {
   BUCKET: R2Bucket
+  FF_TELEMETRY_ENABLED: string
+  HONEYCOMB_API_KEY: string
 }
 
 export declare function handler (request: Request, env: Environment): Promise<Response>