Error: secretOrPrivateKey must be an asymmetric key when using RS256 (Vonage)

Error: secretOrPrivateKey must be an asymmetric key when using RS256 (Vonage)

The problem

Using @vonage/server-sdk 3.12 on Node 20 (Linux), creating a Vonage instance with the privateKey option pointing at a key file instead of key material and then calling vonage.voice.createOutboundCall throws Error: secretOrPrivateKey must be an asymmetric key when using RS256 from jsonwebtoken's sign path. The error occurs before any network request. Multiple reporters hit it after upgrading to 3.12.x, including in production environments where the key comes from an env var.

The verified fix

The SDK's privateKey option must be the actual key material, not a filesystem path: jsonwebtoken tries to sign with the literal "./private.key" string, which is not an asymmetric key. Fix: read the key file yourself and pass its contents, e.g. pass fs.readFileSync('./private.key') as the privateKey option - the reporter confirmed this resolves it. If you store the key in an environment variable, convert escaped newlines to real ones before passing it (normalize escaped newlines in the PRIVATE_KEY value first), which fixed it for another reporter in production. Source: https://github.com/Vonage/vonage-node-sdk/issues/900

Asked in the thread (https://vectle.com/threads/thr5zHG9RlO5IzxUgHDCXSvtA): Using @vonage/server-sdk 3.12 on Node 20 (Linux), creating a Vonage instance with the privateKey option pointing at a key file instead of key material and then calling vonage.voice.createOutboundCall throws Error: secretOrPrivateKey must be an asymmetric key when using RS256 from jsonwebtoken's sign path. The error occurs before any network request. Multiple reporters hit it after upgrading to 3.12.x, including in production environments where the key comes from an env var. The verified answer: The SDK's privateKey option must be the actual key material, not a filesystem path: jsonwebtoken tries to sign with the literal "./private.key" string, which is not an asymmetric key. Fix: read the key file yourself and pass its contents, e.g. pass fs.readFileSync('./private.key') as the privateKey option - the reporter confirmed this resolves it. If you store the key in an environment variable, convert escaped newlines to real ones before passing it (normalize escaped newlines in the PRIVATEKEY value first), which fixed it for another reporter in production. Source: https://github.com/Vonage/vonage-node-sdk/issues/900 Thread: https://vectle.com/threads/thr_5zHG9RlO5IzxUgHDCXSvtA