Callback must be a function, received undefined when using `BlobS3Backend`

[umesh-timalsina]

I am using an S3 compatible minio storage bucket as a backend for one of our webgme deployments, with the following configuration the blob.

config.blob.s3 = {
    accessKeyId: process.env.MINIO_ACCESS_KEY,
    secretAccessKey: process.env.MINIO_SECRET_KEY,
    region: '',
    s3ForcePathStyle: true,
    endpoint: 'http://localhost:9001',
    sslEnabled: false
}

However, it looks like there's a missing callback function on the following line.

The error stack is below:

{
  date: 'Tue Aug 16 2022 10:50:11 GMT-0500 (Central Daylight Time)',
  process: {
    pid: 85750,
    uid: 1000,
    gid: 1000,
    cwd: '/home/umesh/isis/symbench/scm/model_trainer',
    execPath: '/home/umesh/.nvm/versions/node/v14.20.0/bin/node',
    version: 'v14.20.0',
    argv: [
      '/home/umesh/.nvm/versions/node/v14.20.0/bin/node',
      '/home/umesh/isis/symbench/scm/model_trainer/app.js'
    ],
    memoryUsage: {
      rss: 98295808,
      heapTotal: 29528064,
      heapUsed: 27617576,
      external: 22791369,
      arrayBuffers: 20007815
    }
  },
  os: { loadavg: [ 1.83, 1.26, 1.34 ], uptime: 64031.5 },
  trace: [
    {
      column: 7,
      file: 'internal/errors.js',
      function: 'new NodeError',
      line: 322,
      method: null,
      native: false
    },
    {
      column: 11,
      file: 'fs.js',
      function: 'makeCallback',
      line: 177,
      method: null,
      native: false
    },
    {
      column: 14,
      file: 'fs.js',
      function: 'Object.unlink',
      line: 1245,
      method: 'unlink',
      native: false
    },
    {
      column: 20,
      file: '/home/umesh/isis/symbench/scm/model_trainer/node_modules/webgme-engine/src/server/middleware/blob/BlobS3Backend.js',
      function: null,
      line: 124,
      method: null,
      native: false
    },
    {
      column: 28,
      file: 'events.js',
      function: 'ReadStream.emit',
      line: 400,
      method: 'emit',
      native: false
    },
    {
      column: 12,
      file: 'domain.js',
      function: 'ReadStream.emit',
      line: 475,
      method: 'emit',
      native: false
    },
    {
      column: 10,
      file: 'internal/streams/destroy.js',
      function: 'emitCloseNT',
      line: 87,
      method: null,
      native: false
    },
    {
      column: 21,
      file: 'internal/process/task_queues.js',
      function: 'processTicksAndRejections',
      line: 81,
      method: null,
      native: false
    }
  ],
  stack: [
    'TypeError [ERR_INVALID_CALLBACK]: Callback must be a function. Received undefined',
    '    at new NodeError (internal/errors.js:322:7)',
    '    at makeCallback (fs.js:177:11)',
    '    at Object.unlink (fs.js:1245:14)',
    '    at ReadStream.<anonymous> (/home/umesh/isis/symbench/scm/model_trainer/node_modules/webgme-engine/src/server/middleware/blob/BlobS3Backend.js:124:20)',
    '    at ReadStream.emit (events.js:400:28)',
    '    at ReadStream.emit (domain.js:475:12)',
    '    at emitCloseNT (internal/streams/destroy.js:87:10)',
    '    at processTicksAndRejections (internal/process/task_queues.js:81:21)'
  ]
}