fix(core): support OTLP protobuf protocol

packages/core/package.json

@@ -94,6 +94,7 @@
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/context-async-hooks": "2.6.1",
     "@opentelemetry/exporter-trace-otlp-http": "0.214.0",
+    "@opentelemetry/exporter-trace-otlp-proto": "0.214.0",
     "@opentelemetry/sdk-trace-base": "2.6.1",
     "@parcel/watcher": "2.5.1",
     "@silvia-odwyer/photon-node": "0.3.4",

packages/core/src/flag/flag.ts

@@ -16,6 +16,18 @@ export const Flag = {
   OTEL_EXPORTER_OTLP_ENDPOINT: process.env["OTEL_EXPORTER_OTLP_ENDPOINT"],
   OTEL_EXPORTER_OTLP_HEADERS: process.env["OTEL_EXPORTER_OTLP_HEADERS"],
 
+  // Evaluated at access time because tests and embedding runtimes can set OTLP
+  // protocol env vars after this module has loaded.
+  get OTEL_EXPORTER_OTLP_PROTOCOL() {
+    return process.env["OTEL_EXPORTER_OTLP_PROTOCOL"]
+  },
+  get OTEL_EXPORTER_OTLP_TRACES_PROTOCOL() {
+    return process.env["OTEL_EXPORTER_OTLP_TRACES_PROTOCOL"]
+  },
+  get OTEL_EXPORTER_OTLP_LOGS_PROTOCOL() {
+    return process.env["OTEL_EXPORTER_OTLP_LOGS_PROTOCOL"]
+  },
+
   OPENCODE_AUTO_HEAP_SNAPSHOT: truthy("OPENCODE_AUTO_HEAP_SNAPSHOT"),
   OPENCODE_GIT_BASH_PATH: process.env["OPENCODE_GIT_BASH_PATH"],
   OPENCODE_CONFIG: process.env["OPENCODE_CONFIG"],

packages/core/src/observability.ts

@@ -3,15 +3,14 @@ export * as Observability from "./observability"
 import { NodeFileSystem } from "@effect/platform-node"
 import { Effect, Layer, Logger, References } from "effect"
 import { FetchHttpClient } from "effect/unstable/http"
-import { OtlpSerialization } from "effect/unstable/observability"
 import { Logging } from "./observability/logging"
 import { Otlp } from "./observability/otlp"
 
 export const layer = Layer.unwrap(
   Effect.gen(function* () {
     const logs = Logger.layer([...Logging.loggers(), ...Otlp.loggers()], { mergeWithExisting: false }).pipe(
       Layer.provide(NodeFileSystem.layer),
-      Layer.provide(OtlpSerialization.layerJson),
+      Layer.provide(Otlp.serializationLayer()),
       Layer.provide(FetchHttpClient.layer),
       Layer.orDie,
       Layer.merge(Layer.succeed(References.MinimumLogLevel, Logging.minimumLogLevel())),

packages/core/src/observability/otlp.ts

@@ -1,11 +1,16 @@
 import { Layer } from "effect"
-import { OtlpLogger } from "effect/unstable/observability"
+import { OtlpLogger, OtlpSerialization } from "effect/unstable/observability"
 import { Flag } from "../flag/flag"
 import { InstallationChannel, InstallationVersion } from "../installation/version"
 import { runID } from "./shared"
 
 const endpoint = Flag.OTEL_EXPORTER_OTLP_ENDPOINT
 
+export type OtlpProtocol = "http/json" | "http/protobuf"
+export type OtlpSignal = "logs" | "traces"
+
+const defaultProtocol: OtlpProtocol = "http/json"
+
 const headers = Flag.OTEL_EXPORTER_OTLP_HEADERS
   ? Flag.OTEL_EXPORTER_OTLP_HEADERS.split(",").reduce(
       (acc, entry) => {
@@ -17,6 +22,24 @@ const headers = Flag.OTEL_EXPORTER_OTLP_HEADERS
     )
   : undefined
 
+function protocolValue(signal: OtlpSignal) {
+  return (
+    (signal === "logs" ? Flag.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL : Flag.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL) ??
+    Flag.OTEL_EXPORTER_OTLP_PROTOCOL
+  )
+}
+
+export function protocol(signal: OtlpSignal): OtlpProtocol {
+  const value = protocolValue(signal)
+  if (value === "http/json") return value
+  if (value === "http/protobuf") return value
+  return defaultProtocol
+}
+
+export function serializationLayer() {
+  return protocol("logs") === "http/protobuf" ? OtlpSerialization.layerProtobuf : OtlpSerialization.layerJson
+}
+
 function resourceAttributes() {
   const value = process.env.OTEL_RESOURCE_ATTRIBUTES
   if (!value) return {}
@@ -55,7 +78,10 @@ export function loggers() {
 export async function tracingLayer() {
   if (!endpoint) return Layer.empty
   const NodeSdk = await import("@effect/opentelemetry/NodeSdk")
-  const OTLP = await import("@opentelemetry/exporter-trace-otlp-http")
+  const OTLP =
+    protocol("traces") === "http/protobuf"
+      ? await import("@opentelemetry/exporter-trace-otlp-proto")
+      : await import("@opentelemetry/exporter-trace-otlp-http")
   const SdkBase = await import("@opentelemetry/sdk-trace-base")
   const { AsyncLocalStorageContextManager } = await import("@opentelemetry/context-async-hooks")
   const { context } = await import("@opentelemetry/api")

packages/core/test/effect/observability.test.ts

@@ -1,23 +1,73 @@
 import { afterEach, describe, expect, test } from "bun:test"
 import { NodeFileSystem } from "@effect/platform-node"
 import { Effect, Layer, Logger } from "effect"
+import { OtlpSerialization } from "effect/unstable/observability"
 import fs from "fs/promises"
 import os from "os"
 import path from "path"
 import { fileLogger } from "../../src/observability/logging"
-import { resource } from "../../src/observability/otlp"
+import { protocol, resource, serializationLayer } from "../../src/observability/otlp"
 
 const otelResourceAttributes = process.env.OTEL_RESOURCE_ATTRIBUTES
+const otelProtocol = process.env.OTEL_EXPORTER_OTLP_PROTOCOL
+const otelTracesProtocol = process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL
+const otelLogsProtocol = process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
 const opencodeClient = process.env.OPENCODE_CLIENT
 
 afterEach(() => {
   if (otelResourceAttributes === undefined) delete process.env.OTEL_RESOURCE_ATTRIBUTES
   else process.env.OTEL_RESOURCE_ATTRIBUTES = otelResourceAttributes
+  if (otelProtocol === undefined) delete process.env.OTEL_EXPORTER_OTLP_PROTOCOL
+  else process.env.OTEL_EXPORTER_OTLP_PROTOCOL = otelProtocol
+  if (otelTracesProtocol === undefined) delete process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL
+  else process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL = otelTracesProtocol
+  if (otelLogsProtocol === undefined) delete process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
+  else process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL = otelLogsProtocol
 
   if (opencodeClient === undefined) delete process.env.OPENCODE_CLIENT
   else process.env.OPENCODE_CLIENT = opencodeClient
 })
 
+describe("protocol", () => {
+  test("defaults to json", () => {
+    delete process.env.OTEL_EXPORTER_OTLP_PROTOCOL
+    delete process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL
+    delete process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
+
+    expect(protocol("logs")).toBe("http/json")
+    expect(protocol("traces")).toBe("http/json")
+    expect(serializationLayer()).toBe(OtlpSerialization.layerJson)
+  })
+
+  test("uses general protobuf protocol for logs and traces", () => {
+    process.env.OTEL_EXPORTER_OTLP_PROTOCOL = "http/protobuf"
+    delete process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL
+    delete process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
+
+    expect(protocol("logs")).toBe("http/protobuf")
+    expect(protocol("traces")).toBe("http/protobuf")
+    expect(serializationLayer()).toBe(OtlpSerialization.layerProtobuf)
+  })
+
+  test("signal-specific protocol overrides the general protocol", () => {
+    process.env.OTEL_EXPORTER_OTLP_PROTOCOL = "http/protobuf"
+    process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL = "http/json"
+    process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL = "http/protobuf"
+
+    expect(protocol("logs")).toBe("http/protobuf")
+    expect(protocol("traces")).toBe("http/json")
+    expect(serializationLayer()).toBe(OtlpSerialization.layerProtobuf)
+  })
+
+  test("unsupported protocol falls back to json", () => {
+    process.env.OTEL_EXPORTER_OTLP_PROTOCOL = "grpc"
+    delete process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL
+    delete process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL
+
+    expect(protocol("logs")).toBe("http/json")
+  })
+})
+
 describe("resource", () => {
   test("parses and decodes OTEL resource attributes", () => {
     process.env.OTEL_RESOURCE_ATTRIBUTES =

packages/opencode/package.json

@@ -94,6 +94,7 @@
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/context-async-hooks": "2.6.1",
     "@opentelemetry/exporter-trace-otlp-http": "0.214.0",
+    "@opentelemetry/exporter-trace-otlp-proto": "0.214.0",
     "@opentelemetry/sdk-trace-base": "2.6.1",
     "@opentelemetry/sdk-trace-node": "2.6.1",
     "@opentui/core": "catalog:",

packages/opencode/src/control-plane/workspace.ts

@@ -548,6 +548,9 @@ export const layer = Layer.effect(
         OPENCODE_EXPERIMENTAL_WORKSPACES: "true",
         OTEL_EXPORTER_OTLP_HEADERS: process.env.OTEL_EXPORTER_OTLP_HEADERS,
         OTEL_EXPORTER_OTLP_ENDPOINT: process.env.OTEL_EXPORTER_OTLP_ENDPOINT,
+        OTEL_EXPORTER_OTLP_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_PROTOCOL,
+        OTEL_EXPORTER_OTLP_TRACES_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL,
+        OTEL_EXPORTER_OTLP_LOGS_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL,
         OTEL_RESOURCE_ATTRIBUTES: process.env.OTEL_RESOURCE_ATTRIBUTES,
       }
 

packages/opencode/test/control-plane/workspace.test.ts

@@ -40,6 +40,9 @@ const originalEnv = {
   OPENCODE_EXPERIMENTAL_WORKSPACES: process.env.OPENCODE_EXPERIMENTAL_WORKSPACES,
   OTEL_EXPORTER_OTLP_HEADERS: process.env.OTEL_EXPORTER_OTLP_HEADERS,
   OTEL_EXPORTER_OTLP_ENDPOINT: process.env.OTEL_EXPORTER_OTLP_ENDPOINT,
+  OTEL_EXPORTER_OTLP_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_PROTOCOL,
+  OTEL_EXPORTER_OTLP_TRACES_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL,
+  OTEL_EXPORTER_OTLP_LOGS_PROTOCOL: process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL,
   OTEL_RESOURCE_ATTRIBUTES: process.env.OTEL_RESOURCE_ATTRIBUTES,
 }
 
@@ -428,6 +431,9 @@ describe("workspace CRUD", () => {
         process.env.OPENCODE_AUTH_CONTENT = JSON.stringify({ test: { type: "api", key: "secret" } })
         process.env.OTEL_EXPORTER_OTLP_HEADERS = "authorization=otel"
         process.env.OTEL_EXPORTER_OTLP_ENDPOINT = "https://otel.test"
+        process.env.OTEL_EXPORTER_OTLP_PROTOCOL = "http/protobuf"
+        process.env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL = "http/json"
+        process.env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL = "http/protobuf"
         process.env.OTEL_RESOURCE_ATTRIBUTES = "service.name=opencode-test"
 
         const workspaceID = WorkspaceV2.ID.ascending("wrk_create_local")
@@ -491,6 +497,9 @@ describe("workspace CRUD", () => {
         expect(recorded.calls.create[0].env.OPENCODE_EXPERIMENTAL_WORKSPACES).toBe("true")
         expect(recorded.calls.create[0].env.OTEL_EXPORTER_OTLP_HEADERS).toBe("authorization=otel")
         expect(recorded.calls.create[0].env.OTEL_EXPORTER_OTLP_ENDPOINT).toBe("https://otel.test")
+        expect(recorded.calls.create[0].env.OTEL_EXPORTER_OTLP_PROTOCOL).toBe("http/protobuf")
+        expect(recorded.calls.create[0].env.OTEL_EXPORTER_OTLP_TRACES_PROTOCOL).toBe("http/json")
+        expect(recorded.calls.create[0].env.OTEL_EXPORTER_OTLP_LOGS_PROTOCOL).toBe("http/protobuf")
         expect(recorded.calls.create[0].env.OTEL_RESOURCE_ATTRIBUTES).toBe("service.name=opencode-test")
         expect((yield* workspace.status()).find((item) => item.workspaceID === workspaceID)?.status).toBe("connected")