gliner-node-wrapper/index.js

Node.js wrapper around Python-based GlinER NER library

const { spawn } = require('child_process');
const path = require('path');

function extractEntities(text, labels, timeoutMs = 30000) {
  return new Promise((resolve, reject) => {
    if (typeof text !== 'string' || !Array.isArray(labels)) {
      return reject(new Error('Invalid input: "text" must be a string and "labels" an array.'));
    }

    const scriptPath = path.join(__dirname, 'gliner_wrapper.py');
    const pythonProcess = spawn('python3', [scriptPath], {
      stdio: ['pipe', 'pipe', 'pipe']
    });

    const payload = JSON.stringify({ text, labels });

    let stdout = '';
    let stderr = '';
    let timer = setTimeout(() => {
      pythonProcess.kill('SIGKILL');
      reject(new Error('Python script timed out'));
    }, timeoutMs);

    pythonProcess.stdout.on('data', (data) => {
      stdout += data.toString();
    });

    pythonProcess.stderr.on('data', (data) => {
      stderr += data.toString();
    });

    pythonProcess.on('error', (err) => {
      clearTimeout(timer);
      reject(err);
    });

    pythonProcess.on('close', (code) => {
      clearTimeout(timer);
      if (code !== 0) {
        return reject(new Error(stderr || `Python script exited with code ${code}`));
      }

      try {
        const result = JSON.parse(stdout);
        if (result.status === 'error') {
          return reject(new Error(result.message));
        }
        resolve(result.entities);
      } catch (err) {
        reject(new Error('Failed to parse Python output: ' + err.message));
      }
    });

    pythonProcess.stdin.write(payload);
    pythonProcess.stdin.end();
  });
}

module.exports = { extractEntities };