feat: add opencode provider support

apps/server/package.json

@@ -27,6 +27,7 @@
     "@effect/platform-bun": "catalog:",
     "@effect/platform-node": "catalog:",
     "@effect/sql-sqlite-bun": "catalog:",
+    "@opencode-ai/sdk": "^1.3.15",
     "@pierre/diffs": "^1.1.0-beta.16",
     "effect": "catalog:",
     "node-pty": "^1.1.0",

apps/server/src/git/Layers/OpenCodeTextGeneration.test.ts

@@ -0,0 +1,259 @@
+import type { ChildProcess } from "node:child_process";
+
+import * as NodeServices from "@effect/platform-node/NodeServices";
+import { it } from "@effect/vitest";
+import { Duration, Effect, Layer } from "effect";
+import { TestClock } from "effect/testing";
+import { beforeEach, expect, vi } from "vitest";
+
+import { ServerConfig } from "../../config.ts";
+import { ServerSettingsService } from "../../serverSettings.ts";
+import { TextGeneration } from "../Services/TextGeneration.ts";
+import { OpenCodeTextGenerationLive } from "./OpenCodeTextGeneration.ts";
+
+const runtimeMock = vi.hoisted(() => {
+  const state = {
+    startCalls: [] as string[],
+    promptUrls: [] as string[],
+    authHeaders: [] as Array<string | null>,
+    closeCalls: [] as string[],
+    promptResult: undefined as { data?: { info?: { structured?: unknown } } } | undefined,
+  };
+
+  return {
+    state,
+    reset() {
+      state.startCalls.length = 0;
+      state.promptUrls.length = 0;
+      state.authHeaders.length = 0;
+      state.closeCalls.length = 0;
+      state.promptResult = undefined;
+    },
+  };
+});
+
+vi.mock("../../provider/opencodeRuntime.ts", async () => {
+  const actual = await vi.importActual<typeof import("../../provider/opencodeRuntime.ts")>(
+    "../../provider/opencodeRuntime.ts",
+  );
+
+  return {
+    ...actual,
+    startOpenCodeServerProcess: vi.fn(async ({ binaryPath }: { binaryPath: string }) => {
+      const index = runtimeMock.state.startCalls.length + 1;
+      const url = `http://127.0.0.1:${4_300 + index}`;
+      runtimeMock.state.startCalls.push(binaryPath);
+      return {
+        url,
+        process: {} as ChildProcess,
+        close: () => {
+          runtimeMock.state.closeCalls.push(url);
+        },
+      };
+    }),
+    createOpenCodeSdkClient: vi.fn(
+      ({ baseUrl, serverPassword }: { baseUrl: string; serverPassword?: string }) => ({
+        session: {
+          create: vi.fn(async () => ({ data: { id: `${baseUrl}/session` } })),
+          prompt: vi.fn(async () => {
+            runtimeMock.state.promptUrls.push(baseUrl);
+            runtimeMock.state.authHeaders.push(
+              serverPassword ? `Basic ${btoa(`opencode:${serverPassword}`)}` : null,
+            );
+            return (
+              runtimeMock.state.promptResult ?? {
+                data: {
+                  info: {
+                    structured: {
+                      subject: "Improve OpenCode reuse",
+                      body: "Reuse one server for the full action.",
+                    },
+                  },
+                },
+              }
+            );
+          }),
+        },
+      }),
+    ),
+  };
+});
+
+const DEFAULT_TEST_MODEL_SELECTION = {
+  provider: "opencode" as const,
+  model: "openai/gpt-5",
+};
+
+const OPENCODE_TEXT_GENERATION_IDLE_TTL_MS = 30_000;
+
+const OpenCodeTextGenerationTestLayer = OpenCodeTextGenerationLive.pipe(
+  Layer.provideMerge(
+    ServerSettingsService.layerTest({
+      providers: {
+        opencode: {
+          binaryPath: "fake-opencode",
+        },
+      },
+    }),
+  ),
+  Layer.provideMerge(
+    ServerConfig.layerTest(process.cwd(), {
+      prefix: "t3code-opencode-text-generation-test-",
+    }),
+  ),
+  Layer.provideMerge(NodeServices.layer),
+);
+
+const OpenCodeTextGenerationExistingServerTestLayer = OpenCodeTextGenerationLive.pipe(
+  Layer.provideMerge(
+    ServerSettingsService.layerTest({
+      providers: {
+        opencode: {
+          binaryPath: "fake-opencode",
+          serverUrl: "http://127.0.0.1:9999",
+          serverPassword: "secret-password",
+        },
+      },
+    }),
+  ),
+  Layer.provideMerge(
+    ServerConfig.layerTest(process.cwd(), {
+      prefix: "t3code-opencode-text-generation-existing-server-test-",
+    }),
+  ),
+  Layer.provideMerge(NodeServices.layer),
+);
+
+beforeEach(() => {
+  runtimeMock.reset();
+});
+
+const advanceIdleClock = Effect.gen(function* () {
+  yield* Effect.yieldNow;
+  yield* TestClock.adjust(Duration.millis(OPENCODE_TEXT_GENERATION_IDLE_TTL_MS + 1));
+  yield* Effect.yieldNow;
+});
+
+it.layer(OpenCodeTextGenerationTestLayer)("OpenCodeTextGenerationLive", (it) => {
+  it.effect("reuses a warm server across back-to-back requests and closes it after idling", () =>
+    Effect.gen(function* () {
+      const textGeneration = yield* TextGeneration;
+
+      yield* textGeneration.generateCommitMessage({
+        cwd: process.cwd(),
+        branch: "feature/opencode-reuse",
+        stagedSummary: "M README.md",
+        stagedPatch: "diff --git a/README.md b/README.md",
+        modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+      });
+      yield* textGeneration.generateCommitMessage({
+        cwd: process.cwd(),
+        branch: "feature/opencode-reuse",
+        stagedSummary: "M README.md",
+        stagedPatch: "diff --git a/README.md b/README.md",
+        modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+      });
+
+      expect(runtimeMock.state.startCalls).toEqual(["fake-opencode"]);
+      expect(runtimeMock.state.promptUrls).toEqual([
+        "http://127.0.0.1:4301",
+        "http://127.0.0.1:4301",
+      ]);
+      expect(runtimeMock.state.closeCalls).toEqual([]);
+
+      yield* advanceIdleClock;
+
+      expect(runtimeMock.state.closeCalls).toEqual(["http://127.0.0.1:4301"]);
+    }).pipe(Effect.provide(TestClock.layer())),
+  );
+
+  it.effect("starts a new server after the warm server idles out", () =>
+    Effect.gen(function* () {
+      const textGeneration = yield* TextGeneration;
+
+      yield* textGeneration.generateCommitMessage({
+        cwd: process.cwd(),
+        branch: "feature/opencode-reuse",
+        stagedSummary: "M README.md",
+        stagedPatch: "diff --git a/README.md b/README.md",
+        modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+      });
+
+      yield* advanceIdleClock;
+
+      yield* textGeneration.generateCommitMessage({
+        cwd: process.cwd(),
+        branch: "feature/opencode-reuse",
+        stagedSummary: "M README.md",
+        stagedPatch: "diff --git a/README.md b/README.md",
+        modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+      });
+
+      expect(runtimeMock.state.startCalls).toEqual(["fake-opencode", "fake-opencode"]);
+      expect(runtimeMock.state.promptUrls).toEqual([
+        "http://127.0.0.1:4301",
+        "http://127.0.0.1:4302",
+      ]);
+      expect(runtimeMock.state.closeCalls).toEqual(["http://127.0.0.1:4301"]);
+    }).pipe(Effect.provide(TestClock.layer())),
+  );
+
+  it.effect("returns a typed missing-output error when OpenCode omits info.structured", () =>
+    Effect.gen(function* () {
+      runtimeMock.state.promptResult = { data: {} };
+      const textGeneration = yield* TextGeneration;
+
+      const error = yield* textGeneration
+        .generateCommitMessage({
+          cwd: process.cwd(),
+          branch: "feature/opencode-reuse",
+          stagedSummary: "M README.md",
+          stagedPatch: "diff --git a/README.md b/README.md",
+          modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+        })
+        .pipe(Effect.flip);
+
+      expect(error.message).toContain("OpenCode returned no structured output.");
+    }),
+  );
+});
+
+it.layer(OpenCodeTextGenerationExistingServerTestLayer)(
+  "OpenCodeTextGenerationLive with configured server URL",
+  (it) => {
+    it.effect("reuses a configured OpenCode server URL without spawning or applying idle TTL", () =>
+      Effect.gen(function* () {
+        const textGeneration = yield* TextGeneration;
+
+        yield* textGeneration.generateCommitMessage({
+          cwd: process.cwd(),
+          branch: "feature/opencode-reuse",
+          stagedSummary: "M README.md",
+          stagedPatch: "diff --git a/README.md b/README.md",
+          modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+        });
+        yield* textGeneration.generateCommitMessage({
+          cwd: process.cwd(),
+          branch: "feature/opencode-reuse",
+          stagedSummary: "M README.md",
+          stagedPatch: "diff --git a/README.md b/README.md",
+          modelSelection: DEFAULT_TEST_MODEL_SELECTION,
+        });
+
+        expect(runtimeMock.state.startCalls).toEqual([]);
+        expect(runtimeMock.state.promptUrls).toEqual([
+          "http://127.0.0.1:9999",
+          "http://127.0.0.1:9999",
+        ]);
+        expect(runtimeMock.state.authHeaders).toEqual([
+          `Basic ${btoa("opencode:secret-password")}`,
+          `Basic ${btoa("opencode:secret-password")}`,
+        ]);
+
+        yield* advanceIdleClock;
+
+        expect(runtimeMock.state.closeCalls).toEqual([]);
+      }).pipe(Effect.provide(TestClock.layer())),
+    );
+  },
+);