Catch the status of a child process as a stream error

[mafintosh]

Catch the status of a child process as a stream error

[istarkov]

Modern days you can use async iterables instead of duplexify

I use spawn wrapper like

  const someCmd = (cmd:string) => {
    // eslint-disable-next-line @typescript-eslint/no-unused-vars
    let resolve_ = (_value?: unknown) => {
      //
    };

    // eslint-disable-next-line @typescript-eslint/no-unused-vars
    let reject_ = (_e: Error) => {
      //
    };

    const pWait = new Promise((r, rj) => {
      resolve_ = r;
      reject_ = rj;
    });

    const psql = spawn(execCmd, [...execArgs, ...commonArgs, '-c', cmd], {
      stdio: ['pipe', 'pipe', process.stderr],
    });

    psql.on('exit', code => {
      if (code != null && code > 0) {
        // throw new Error('process exited with error');
        console.error('EXIT CODE');
        reject_(new Error('process exited with non null code'));
      }
      resolve_();
    });

    // return stream;
    return async function* (source: NodeJS.ReadableStream) {
      if (source != null) {
        source.setEncoding('utf8');
        pipeline(source, psql.stdin, err => {
          if (err != null) {
            reject_(err);
          }
        });
      }

      for await (const chunk of psql.stdout) {
        yield chunk;
      }

      await pWait;
    } as never;
  };

Then

try {
await pipeline(
  eee(),
  someCmd(),
  blabla()
)
} catch(e) {
  <--- In case of spawn returns error code will be here
}