SDB

Simple DataBase is a simpler IndexedDB Module

This module is a vanilla-JavaScript library for manipulating the HTML5 IndexedDB API. Its main goals are simplicity and intuitiveness.

NOTE:

For ease of testing, its recommended that you use an IndexedDB-database-wiper such as "History Eraser" @ https://chrome.google.com/webstore/search-apps/history%20eraser?utm_campaign=en&utm_source=ha-en-na-us-webapp-collections-editors_picks&utm_medium=ha

...Or a better one(?)

Quick Start

Point to SDB:

<script src="path/to/SDB.js"></script>

The javascript:

var PeopleDBschema = {
	db: 'PeopleDB',
	v: 1,
	upgrade: {
		stores: [
			{
				name: 'humans',
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			},
			{
				name: 'aliens',
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			}
		]
	} 
};

var PeopleDBHook = sdb.req(PeopleDBschema, function(PeopleDB){  // create database from schema
	PeopleDBHook.tr(PeopleDB, ['humans', 'aliens'], 'readwrite')
		.store('humans')
		.put({id: 1, name: 'versions', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'}
			] // we added "id" some that if db is created&pagerefreshed, it still "puts"
		})
		.get('[email protected]', function(item){
			console.log('humans GOT ITEM', item);	
		})
		.store('aliens')
		.put({id: 1, name: 'versions', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'}
			]
		})
		.get('[email protected]', function(item){
			console.log('aliens GOT ITEM', item);	
		});
		.cursor(function(data){
			console.log('aliens data', data);
		});

	PeopleDBHook.tr(PeopleDB, ['humans', 'aliens'], 'readwrite')
		.store('aliens')
		.put({id: 1, name: 'versions', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'}
			]
		});
});

var PeopleDBHook = sdb.req('PeopleDB', function(PeopleDB){  // reopen database
	PeopleDBHook.tr(PeopleDB, ['humans', 'aliens'], 'readwrite')
		.store('aliens')
		.put({id: 1, name: 'versions1', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'},
				{versionName: 'myOtherVersionName5', pubKey: 'myOtherPubKey5'},
				{versionName: 'myOtherVersionName6', pubKey: 'myOtherPubKey6'}
			]
		})
		.put({id: 2, name: 'versions2', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'},
				{versionName: 'myOtherVersionName5', pubKey: 'myOtherPubKey5'},
				{versionName: 'myOtherVersionName6', pubKey: 'myOtherPubKey6'}
			]
		})
		.put({id: 3, name: 'versions3', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'},
				{versionName: 'myOtherVersionName5', pubKey: 'myOtherPubKey5'},
				{versionName: 'myOtherVersionName6', pubKey: 'myOtherPubKey6'}
			]
		})
		.put({id: 4, name: 'versions4', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'},
				{versionName: 'myOtherVersionName5', pubKey: 'myOtherPubKey5'},
				{versionName: 'myOtherVersionName6', pubKey: 'myOtherPubKey6'}
			]
		})
		.cursor(function(data){  // just a callback
			console.log('@OpenCursor _');
			console.log('@OpenCursor:', data);
		})
		.cursor(function(data){  // callback and an index id
			console.log('@OpenCursor 2');
			console.log('@OpenCursor:', data);
		}, 2)
		.cursor(function(data){  // callback and range with direction
			console.log("@OpenCursor {bound: [1, 8], direction: 'prev'}");
			console.log('@OpenCursor:', data);
		}, {bound: [1, 8], direction: 'prev'})
		.cursor(function(data){  // range with range points excluded
			console.log("@OpenCursor {bound: [1, 3, true, true]}");
			console.log('@OpenCursor:', data);
		}, {bound: [1, 4, true, true]});  // {bound: [1, 8], direction: 'next'} 2
});

Overview

Create A New Database:

var PeopleDBHook = sdb.req(PeopleDBschema, function(PeopleDB){  // create database from schema
	// ALL [INITIAL] transactions for "PeopleDB" go here!
});

To create or open an IndexedDB database, you need to have a schema in place. In IndexedDB, you need to have a database name and a version to open/create one. (In IndexedDB, you use the same method to create a new AND open an existing database). Requesting a database will open an existing database or create a new one if it doesn't already exist.

To request a database, use the 'req' method on the API. The 'req' method takes 2 arguments: a database schema, and a callback closure for making transactions.

The Schema:

The schema is an object-literal. It must consist of a 'db' property (which is a string containing the database's name), and a version (for database verioning). On top of a db name and version, you'll need to set up your "ObjectStores" and Indices. You can add multiple ObjectStores and Indices using arrays. The following elucidates what properties are necessary.

var PeopleDBschema = {
	db: 'PeopleDB',
	v: 1,
	upgrade: {
		stores: [
			{
				name: 'humans',
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			},
			{
				name: 'aliens',
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			}
		]
	} 
};

Versioning

To change your DB-Schema based upon version, use the 'v'-property of the schema-object-literal and make sure to remove any stores (schema.upgrade.stores[i]) from the previous versio(s); then add a new store with the appropriate options and indices:

var PeopleDBschema = {
	db: 'PeopleDB',
	v: 2,
	upgrade: {
		stores: [
			{
				name: 'cats',  // I'm a cat-lover
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			},
			{
				name: 'dogs',  // I'm a dog-lover
				opts: {keyPath: 'id', autoIncrement: true},
				indices: [
					{index: 'name', opts: {unique: false}},
					{index: 'email', opts: {unique: true}}
				]
			}
		]
	} 
};

After creating a new schema-object for this new version, it is recommended that you store previous version-schemas in a README file with a Code-Comment-Note in you code that references the README. (DB-VERSIONING GETS MESSY!!!).

The Callback:

The callback function will receive the database that was requested as an argument. You'll need this for all of your transactions.

var PeopleDBHook = sdb.req(PeopleDBschema, function(PeopleDB){  // create database from schema
	var PeopleDB = PeopleDB;
});

After you have the database-object (passed as the closure's argument), you can begin making transactions using the 'tr()' method (INSIDE OF THE CALLBACK CLOSURE):

Open a transaction:

PeopleDBHook
	.tr(PeopleDB, ['humans'], 'readwrite');

Get an objectStore:

PeopleDBHook
	.tr(PeopleDB, ['humans'], 'readwrite')
	.store('humans');

Make a transaction:

PeopleDBHook
	.tr(PeopleDB, ['humans'], 'readwrite')
	.store('humans')
	.put({name: 'someName', email: '[email protected]'}, function(item){
		console.log('PUT ITEM', item);
	});

Chaining transactions on multiple stores:

PeopleDBHook
	.tr(PeopleDB, ['humans', 'aliens'], 'readwrite')
	.store('humans')
		.get(/* get args */)
	.store('aliens')
		.get(/* get args */);

(Given that each transaction is encapsulated in its own closure, perhaps a more semantic way of doing this could be):

var PeopleDB = sdb.req(PeopleDBschema, function(db){  // create database from schema
	PeopleDB
		.tr(db, ['humans'], 'readwrite')
		.store('humans')
		.put({name: 'someName', email: '[email protected]'}, function(item){
			console.log('PUT ITEM', item);
		});
});

Reopening The Database:

var PeopleDBHook = sdb.req('PeopleDB', function(PeopleDB){  // reopen database
	PeopleDBHook.tr(PeopleDB, ['humans', 'aliens'], 'readwrite')
		.store('aliens')
		.put({id: 1, name: 'versions1', email: '[email protected]', versions: [
				{versionName: 'myOtherVersionName1', pubKey: 'myOtherPubKey1'},
				{versionName: 'myOtherVersionName2', pubKey: 'myOtherPubKey2'},
				{versionName: 'myOtherVersionName3', pubKey: 'myOtherPubKey3'},
				{versionName: 'myOtherVersionName4', pubKey: 'myOtherPubKey4'},
				{versionName: 'myOtherVersionName5', pubKey: 'myOtherPubKey5'},
				{versionName: 'myOtherVersionName6', pubKey: 'myOtherPubKey6'}
			]
		});
});

This is the basic process for CRUDing the an IndexedDB.

See METHODS section for methods and their implementations.

METHODS

req():

1. opens a new or existing database
2. takes a schema-object or a database-name-string as first argument
3. takes a callback-closure as second argument

req.callback()

receives the requested database-object as an argument.

tr():

takes three(3) arguments:

1. the database in action (passed into the req.callback closure)
2. a string of one, or an array of multiple objectStores on which to make transactions
3. the transaction type (read, write, etc)

store():

the store on which the current transactions will be. This can be any from the second argument of the tr() method.

add():

once an objectStore is chosen using the .store() method, .add() can be used to insert NEW data into the database. This method takes two(2) arguments: the data to be added, and a callback. The callback accepts an argument for which item was added.

put():

similar to the add method, this takes data to insert into the database. However, this method is also used to update data.

• To add NEW data, use it analogously to .add().
• To UPDATE data, you MUST include ALL object-properties, ie include "id" etc. The entire object schema must be included and all unique properties must be unique.

del():

NOT YET IMPLEMENTED!!!

get():

takes two(2) arguments. An item, and a callback which accepts the item as an argument.

cursor():

takes ONE to TWO (1-2) arguments. When using just a callback, the cursor will retrieve ALL items in the store.

.cursor(function(data, cursor){console.log(data)});

NOTE: the .cursor() callback accepts two(2) arguments:

• the item retrieved

• the cursor. This allows you to control the continuance of the cursor during retrieval process. EG.

    .cursor(function(data, cursor){
    	if(data.id <= 2){
    		console.log('@OpenCursor__:', data);
    		console.log('data.id === ', data.id, 'condition is: data.id <= 2');
    		cursor.continue();
    	}else{
    		console.log('@OpenCursor__: cursor stopped based upon callback conditions :-) ');
    	}
    });
  

When using a callback and a Number, the cursor will retrieve the item in the store that matches the id (if autoinc' is set).

.cursor(function(data, cursor){console.log(data)}, 2);

When using a callback and a range, the cursor will retrieve ALL items in the store which match the range.

.cursor(function(data, cursor){console.log(data)}, {bound: [n, n], direction: 'prev'});

'bound' takes two numbers, while direction takes a string that is either 'prev', or 'next'.

When using a callback and a range with exclusions, the cursor will retrieve ALL items in the store according to criteria.

.cursor(function(data, cursor){console.log(data)}, {bound: [n1, n2, true, false]});

Finds items in range, BUT excludes "n1" (true) and NOT "n2" (false).

NOTE: For each of the above, you must still CONTINUE THE CURSOR if you want to keep retrieveing items!

count():

NOT YET IMPLEMENTED!!!

clear():

NOT YET IMPLEMENTED!!!

index():

DETAIL COMMING SOON! :)

index.get():

DETAIL COMMING SOON! :)

index.openCursor():

DETAIL COMMING SOON! :)

index.openKeyCursor():

DETAIL COMMING SOON! :)

deleteIndex():

NOT YET IMPLEMENTED!!!