Author: John Au-Yeung

Sometimes, we want to remove debugging from socket.io.

In this article, we’ll look at how to remove debugging from socket.io.

How to remove debugging from socket.io?

To remove debugging from socket.io, we can set the log option to false when we call listen.

For instance, we write

const io = require('socket.io').listen(app, {
  log: false
});

to call listen with log set to false to disable logging with socket.io.

We can also set the log level with

const io = require('socket.io').listen(app);

io.set('log level', 1);

to set log level to 1 to reduce the level of logging.

Conclusion

To remove debugging from socket.io, we can set the log option to false when we call listen.

Sometimes, we want to set up two different static directories with Node.js Express framework.

In this article, we’ll look at how to set up two different static directories with Node.js Express framework.

How to set up two different static directories with Node.js Express framework?

To set up two different static directories with Node.js Express framework, we can call express.static and app.use with different static file paths.

For instance, we write

app.use("/public", express.static(__dirname + "/public"));
app.use("/public2", express.static(__dirname + "/public2"));

to expose the /public URL path to __dirname + "/public" with express.static.

Likewise, we expose the /public2 URL path to __dirname + "/public2" with express.static.

Conclusion

To set up two different static directories with Node.js Express framework, we can call express.static and app.use with different static file paths.

Sometimes, we want to determine if a string is a MongoDB ObjectID.

In this article, we’ll look at how to determine if a string is a MongoDB ObjectID.

How to determine if a string is a MongoDB ObjectID?

To determine if a string is a MongoDB ObjectID, we can use the mongoose.isValidObjectId method.

For instance, we write

mongoose.isValidObjectId(string);

to call mongoose.isValidObject with the string that we want to check if it’s an ObjectID.

It returns true if string is a valid ObjectID and false otherwise.

Conclusion

To determine if a string is a MongoDB ObjectID, we can use the mongoose.isValidObjectId method.

Sometimes, we want to combine two OR-queries with AND in Mongoose.

In this article, we’ll look at how to combine two OR-queries with AND in Mongoose.

How to combine two OR-queries with AND in Mongoose?

To combine two OR-queries with AND in Mongoose, we can use the find method.

For instance we write

Test.find({
  $and: [{
      $or: [{
        a: 1
      }, {
        b: 1
      }]
    },
    {
      $or: [{
        c: 1
      }, {
        d: 1
      }]
    }
  ]
}, (err, results) => {
  //...
})

to call Test.find with the $and property set to an array with 2 objects with $or properties.

This combines the 2 OR clauses with AND.

We get the query results from results.

Conclusion

To combine two OR-queries with AND in Mongoose, we can use the find method.

Sometimes, we want to write file if parent folder doesn’t exist with Node.js.

In this article, we’ll look at how to write file if parent folder doesn’t exist with Node.js.

How to write file if parent folder doesn’t exist with Node.js?

To write file if parent folder doesn’t exist with Node.js, we can call mkdir to create the folder before creating the file in the folder.

For instance, we write

const fs = require('fs');
const getDirName = require('path').dirname;

fs.mkdir(getDirName(path), {
  recursive: true
}, (err) => {
  if (err) return cb(err);

  fs.writeFile(path, contents, (err) => {
    //...
  });
});

to call fs.mkdir with the folder path we want to create and an object that has recursive set to true to create the folder event if the parent folder doesn’t exist.

Then in the mkdir callback, we call writeFile to write the file to the given path.

Conclusion

To write file if parent folder doesn’t exist with Node.js, we can call mkdir to create the folder before creating the file in the folder.