ComposioHQ/composio · error · Error

File operations (upload/download) are not supported in Cloud

Error message

File operations (upload/download) are not supported in Cloudflare Workers or Edge runtimes. These operations require Node.js-specific APIs (e.g., `node:crypto`, `node:fs`) that are not available in this environment. Please use a Node.js runtime for file operations.

What it means

In Cloudflare Workers / Edge runtimes, the Files model is a Proxy that throws on any method access because file upload/download needs Node.js-only APIs (node:crypto, node:fs). This is a hard runtime capability error, not a data problem.

Source

Thrown at ts/packages/core/src/models/Files.workerd.ts:32

/**
 * Creates a Proxy that throws a user-friendly error when any method is accessed.
 * This ensures that users get a clear error message when attempting to use
 * file operations in unsupported environments.
 */
const createUnsupportedFilesProxy = (): Files => {
  const handler: ProxyHandler<object> = {
    get(_target, prop) {
      // Allow access to constructor name for debugging
      if (prop === Symbol.toStringTag) {
        return 'Files';
      }
      if (prop === 'constructor') {
        return Files;
      }
      // For any method access, return a function that throws
      return () => {
        throw new Error(UNSUPPORTED_MESSAGE);
      };
    },
  };

  return new Proxy({}, handler) as Files;
};

/**
 * Files class for Cloudflare Workers / Edge runtimes.
 * All methods throw an error indicating that file operations are not supported.
 */
export class Files {
  constructor(_client: ComposioClient) {
    // Return a Proxy instead of the actual instance
    return createUnsupportedFilesProxy();
  }
}

View on GitHub (pinned to 64b1b85502)

Solutions

1. Move file upload/download logic to a Node.js runtime (separate service or worker with nodejs_compat plus correct build)
2. Guard file calls behind a runtime check and skip them in Workers
3. If Node APIs are genuinely available, ensure your bundler resolves the node build of @composio/core instead of the workerd build

Example fix

// before
const file = await composio.files.uploadFromPath('/tmp/a.pdf');
// after (route to a Node.js service, or guard)
if (platform.supportsFileSystem) {
  await composio.files.uploadFromPath('/tmp/a.pdf');
}

const supportsNodeFiles = typeof process !== 'undefined' && !!process.versions?.node;
if (!supportsNodeFiles) throw new Error('files API requires Node.js runtime');

const canUseFiles = (): boolean =>
  typeof process !== 'undefined' && Boolean(process.versions?.node);

try { await composio.files.uploadFromPath(p); } catch (e) { if (/not supported in Cloudflare Workers/.test(String(e?.message))) { fallbackToMemoryUpload(); return; } throw e; }

When it happens

Trigger: Importing and calling any method on composio.files (upload/download) in a build resolved to Files.workerd.ts — i.e. running under Cloudflare Workers or an Edge runtime where the workerd build of the SDK is selected.

Common situations: Deploying a Node.js service to Cloudflare Workers without removing file features; bundlers resolving the 'workerd'/edge condition of the package exports; integration tests running in a workerd-compatible environment.

Related errors

• File system operations are not supported in this runtime (e.
• File system operations are not supported in this runtime env
• URL file uploads are not supported in edge runtimes because
• Failed to fetch file from URL: {e.cause}
• URL returned redirect. Please provide a direct URL to the fi

AI-assisted analysis of ComposioHQ/composio@64b1b85502 (2026-08-28). Data as JSON: /api/errors/e233efe62f0b2d47. Report an issue: GitHub.