Add executable detection and export Codex from the SDK (#4532)

Executable detection uses the same rules as the codex wrapper.

sdk/typescript/src/codex.ts

@@ -7,11 +7,7 @@ export class Codex {
   private options: CodexOptions;
 
   constructor(options: CodexOptions) {
-    if (!options.executablePath) {
-      throw new Error("executablePath is required");
-    }
-
-    this.exec = new CodexExec(options.executablePath);
+    this.exec = new CodexExec(options.codexPathOverride);
     this.options = options;
   }
 

sdk/typescript/src/codexOptions.ts

@@ -1,7 +1,5 @@
 export type CodexOptions = {
-  // TODO: remove
-  executablePath: string;
-  // TODO: remove
+  codexPathOverride?: string;
   baseUrl?: string;
   apiKey?: string;
 };

sdk/typescript/src/exec.ts

@@ -1,7 +1,10 @@
 import { spawn } from "child_process";
+
 import readline from "node:readline";
 
 import { SandboxMode } from "./turnOptions";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
 
 export type CodexExecArgs = {
   input: string;
@@ -15,8 +18,8 @@ export type CodexExecArgs = {
 
 export class CodexExec {
   private executablePath: string;
-  constructor(executablePath: string) {
-    this.executablePath = executablePath;
+  constructor(executablePath: string | null = null) {
+    this.executablePath = executablePath || findCodexPath();
   }
 
   async *run(args: CodexExecArgs): AsyncGenerator<string> {
@@ -92,3 +95,64 @@ export class CodexExec {
     }
   }
 }
+
+const scriptFileName = fileURLToPath(import.meta.url);
+const scriptDirName = path.dirname(scriptFileName);
+
+function findCodexPath() {
+  const { platform, arch } = process;
+
+  let targetTriple = null;
+  switch (platform) {
+    case "linux":
+    case "android":
+      switch (arch) {
+        case "x64":
+          targetTriple = "x86_64-unknown-linux-musl";
+          break;
+        case "arm64":
+          targetTriple = "aarch64-unknown-linux-musl";
+          break;
+        default:
+          break;
+      }
+      break;
+    case "darwin":
+      switch (arch) {
+        case "x64":
+          targetTriple = "x86_64-apple-darwin";
+          break;
+        case "arm64":
+          targetTriple = "aarch64-apple-darwin";
+          break;
+        default:
+          break;
+      }
+      break;
+    case "win32":
+      switch (arch) {
+        case "x64":
+          targetTriple = "x86_64-pc-windows-msvc";
+          break;
+        case "arm64":
+          targetTriple = "aarch64-pc-windows-msvc";
+          break;
+        default:
+          break;
+      }
+      break;
+    default:
+      break;
+  }
+
+  if (!targetTriple) {
+    throw new Error(`Unsupported platform: ${platform} (${arch})`);
+  }
+
+  const vendorRoot = path.join(scriptDirName, "..", "vendor");
+  const archRoot = path.join(vendorRoot, targetTriple);
+  const codexBinaryName = process.platform === "win32" ? "codex.exe" : "codex";
+  const binaryPath = path.join(archRoot, "codex", codexBinaryName);
+
+  return binaryPath;
+}

sdk/typescript/src/index.ts

@@ -22,9 +22,9 @@ export type {
   ErrorItem,
 } from "./items";
 
-export type { Thread, RunResult, RunStreamedResult, Input } from "./thread";
+export { Thread, RunResult, RunStreamedResult, Input } from "./thread";
 
-export type { Codex } from "./codex";
+export { Codex } from "./codex";
 
 export type { CodexOptions } from "./codexOptions";