tsDiskDB

A Lightweight Disk based JSON Database with a MongoDB like API for Node, written in TypeScript.

Contents

• tsDiskDB
  • Contents
  • Getting Started
    • Load collections
      • Load multiple collections
    • Save models in a collection
    • Search a collection
    • Find many models in a collection
      • Find one model in a collection
    • Update a collection
    • Remove a collection
    • Count models in a collection
• Appendix

Getting Started

Install the module:

$ npm install tsdiskdb

Import & intitialize it with:

var db = require("tsdiskdb");
// or with the import syntax, if supported:
import db from "tsdiskdb";

Then, connect to a .json 'DB' with:

db.connect(pathToFolder, ["filename"]);

Where filename is the name of the .json file. You can omit the extension. This method also returns the instance itself so it can be used for chaining calls as well.

This will check for a directory at given path, if it does not exits, tsDiskDB will throw an error and exit.

If the directory exists but the file does not exist, tsDiskDB will create it for you.

Note : If you have manually created a JSON file, please make sure it contains a valid JSON array, otherwise tsDiskDB will return an empty array ([]).

Load collections

Alternatively you can also load collections with the following syntaxes:

var db = require("tsdiskdb");

// variant 1
db = db.connect("/path/to/folder");
db.loadCollections(["articles"]);

// variant 2
db.connect("/path/to/folder");
db.loadCollections(["articles"]);

// variant 3
db.connect("/path/to/folder").loadCollections(["articles"]);
//or
db.connect("/path/to/folder", ["articles"]);

Load multiple collections

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles", "users"]);

Save models in a collection

db.collectionName.save(object);

Once you have loaded a collection, you can access the collection's methods the following way:

db.collectionName.methodName;

To save a modified instance of a collection, use:

var db = require("tsdiskdb");
db.connect("db", ["articles"]);

var article = {
	title: "Article 1",
	published: "today",
	rating: "10/10",
};

db.articles.save(article);

The saved data will be

[
	{
		title: "Article 1",
		published: "today",
		rating: "10/10",
		_id: "d6f39a8dc7494d19a3eb60a008e71cd9",
	},
];

You can also save multiple objects at once:

var db = require("tsdiskdb");
db.connect("db", ["articles"]);
var article1 = {
	title: "Article 1",
	published: "today",
	rating: "10/10",
};

var article2 = {
	title: "Article 2",
	published: "yesterday",
	rating: "7/10",
};

db.articles.save([article1, article2]);

And this will return the inserted objects

[
	{
		title: "Article 1",
		published: "today",
		rating: "10/10",
		_id: "628574cc74384f8eb07236ef99140773",
	},
	{
		title: "Article 2",
		published: "yesterday",
		rating: "7/10",
		_id: "fd976e7ba0c64eb8acc2855701c32dfb",
	},
];

Search a collection

To search a collection, use:

• db.collectionName.find({ query }) to find many models matching the specified criteria
• db.collectionName.findOne({ query }) to find just one model matching the specified criteria

Find many models in a collection

Use the following code to find all models in a collection:

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.find();

This will return all the records

[
	{
		title: "tsdiskDB rocks",
		published: "today",
		rating: "5 stars",
		_id: "0f6047c6c69149f0be0c8f5943be91be",
	},
];

You can also query with a criteria that is a partial object of the original one stored.

For example:

db.articles.find({ rating: "7/10", published: "yesterday" });

With the data inside the collection fed by the aforementioned snippets, this would return:

[
	{
		"title": "Article 2",
		"published": "yesterday",
		"rating": "7/10",
		"_id": "fd976e7ba0c64eb8acc2855701c32dfb"
	}
]

Since tsDiskDB is mostly for lightweight data storage, avoid nested structures and huge datasets.

Find one model in a collection

db.articles.findOne();

If you do not pass a query, tsDiskDB will return the first article in the collection. If you pass a query, it will return first article in the filtered data.

db.articles.findOne({ _id: "0f6047c6c69149f0be0c8f5943be91be" });

Note that models can also be queried by their _id field, like above.

Update a collection

db.collectionName.update(query, data, options);

You can also update one or many objects in the collection

options = {
	multi: false, // update multiple - default false
	upsert: false, // if object is not found, add it (update-insert) - default false
};

Sample usage:

var query = {
	title: "tsdiskDB rocks",
};

var dataToBeUpdated = {
	title: "tsdiskDB rocks again!",
};

var options = {
	multi: false,
	upsert: false,
};

var updated = db.articles.update(query, dataToBeUpdated, options);
console.log(updated); // { updated: 1, inserted: 0 }

Remove a collection

db.collectionName.remove(query, multi);

You can remove the entire collection (including the file) or you can remove the matched objects by passing in a query. When you pass a query, you can either delete all the matched objects or only the first one by passing multi as false. The default value of multi is true.

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.remove({ rating: "5 stars" });

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.remove({ rating: "5 stars" }, true); // remove all matched. Default - multi = true

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.remove({ rating: "5 stars" }, false); // remove only the first match

Using remove without any params will delete the file and will remove the db instance.

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.remove();

After the above operation db.articles is undefined.

Count models in a collection

db.collectionName.count();

Will return the count of objects in the Collection

var db = require("tsdiskdb");
db.connect("/path/to/folder", ["articles"]);
db.articles.count(); // will give the count

Appendix

The project was originally based off diskdb and is now a more advanced, improved version of the project, written TypeScript.