Javascript module. Exports a class to make communication with mongodb easier

monconnect.js

const mc = require('mongodb').MongoClient;

class MonCon {
  // Takes all the neede vars to connect to a database
  constructor(host_ip, host_port, db_url, db_name, db_collection) {
    this.host_ip = host_ip;
    this.host_port = host_port;
    this.db_url = db_url;
    this.db_name = db_name;
    this.db_collection = db_collection;
  }

  /* Create methods */
  createCollection(dbName = this.db_name, colName) {
    // Takes two strings and creates a collection in the selected database.
    mc.connect(`${this.db_url} ${dbName}`, (err, db) => {
      if (err) throw err;
      let dbo = db.db(dbName);
      dbo.createCollection(colName, (err, res) => {
        if (err) throw err;
        if (!err) {
          console.log(`Successfully created collection ${colName} in ${dbName}`);
        }
        db.close();
      });
    });
  }
  cOne(newEntry) {
    // Takes an object and creates a new db entry based on its values
    mc.connect(this.db_url, (err, db) => {
      if (err) throw err;
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).insertOne(newEntry, () => {
        if (err) throw err;
        if (!err) {
          console.log(`Successfully inserted the following entry: ${newEntry.name}`);
        }
        db.close();
      });
    });
  };
  cMany(newEntries) {
    // Takes an array of objects and creates new db entries based on its values
    mc.connect(this.db_url, (err, db) => {
      if (err) throw err;
      let dbo = db.db(this.db_name);
      for (let i = 0; i < newEntries.length; i++) {
        dbo.collection(this.db_collection).insertOne(newEntries[i], () => {
          if (err) throw err
          if (!err) {
            console.log(`Successfully inserted the following entry: ${newEntries[i].name}`);
          }
        });
        db.close();
      } // EndFor
    });
  }

  /* Read methods */
  rAll(callback) {
    // Reads all entries from defined collection and returns results in callback
    // Variable to be used is 'arr'
    let arr;

    mc.connect(this.db_url, (err, db) => {
      if (err) throw err;
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).find({}).toArray((err, result) => {
        if (err) throw err;
        arr = result;
        db.close();
        // arr can be used with a callback function
        callback(arr)
      });
    });
  };
  rFilter(query, callback) {
    // Takes in an object key - value pair. Key is the propery that's being
    // queried, value is the specified value to be searched for.
    // Returns a callback that can be worked with.
    console.log(query);
    let arr;
    mc.connect(this.db_url, (err, db) => {
      if (err) throw err;
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).find(query)
        .toArray((err, result) => {
          if (err) throw err;
          arr = result;
          db.close();
          callback(arr);
        });
    });


  }
  // rFilterSome(query, callback) {}

  /* Update methods */
  uOne(query, newEntry) {
    /* Takes in two objects. First object is a key-value pair object.
     * Key is entry to be changed. Value is pattern to be searched for.
     * Second object is a setter ($set) and a linked object with the key-value
     * pairs that are to be changed in the object that matches the query.
     *
     * Example
     * updateCollectionEntryAll({name: "John"}, {adress: "New Hampshire"})
     * => Filter first entry for name = John
     * => Updates these entires adress attribute to New Hampshire
     */
    mc.connect(this.db_url, (err, db) => {
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).updateOne(query, newEntry, (err, res) => {
        if (err) throw err;
        if (!err) {
          console.log(`Successfully updated  ${res.result.nModified} objects`);
        }
        db.close();
      });
    });
  }
  uMany(query, newEntry) {
    /* Takes in two objects. First object is a key-value pair object.
     * Key is entry to be changed. Value is pattern to be searched for.
     * Second object is a setter ($set) and a linked object with the key-value
     * pairs that are to be changed in the objects that match the query.
     *
     * Example
     * updateCollectionEntryAll({name: "John"}, {adress: "New Hampshire"})
     * => Filter all entries for name = John
     * => Updates these entires adress attribute to New Hampshire
     */

    mc.connect(this.db_url, (err, db) => {
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).updateMany(query, newEntry, (err, res) => {
        if (err) throw err;
        if (!err) {
          console.log(`Successfully updated  ${res.result.nModified} objects`);
        }
        db.close();
      });
    });
  }

  /* Delete methods */
  dOne(query) {
    // Takes in an object and deletes the first found entry from the database
    mc.connect(this.db_url, (err, db) => {
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).deleteOne(query, (err, res) => {
        if (err) throw err;
        if (!err) {
          console.log(`Removed ${res.result.n} document(s) from database`);
        }
        db.close()
      });
    });
  }
  dMany(query) {
    // Takes in an object and deletes the first found entry from the database
    mc.connect(this.db_url, (err, db) => {
      let dbo = db.db(this.db_name);
      dbo.collection(this.db_collection).deleteMany(query, (err, res) => {
        if (err) throw err;
        if (!err) {
          console.log(`Removed ${res.result.n} document(s) from database`);
        }
        db.close()
      });
    });
  }

  /* Class Set Methods */
  set setDb(dbName) {
    // Change the object's database
    this.db_name = dbName;
  }
  set setCol(colName) {
    // Change the object's collection
    this.db_collection = colName;
  }
}

module.exports = MonCon;