@dpogue/dexie
v1.4.1
Published
A Minimalistic Wrapper for IndexedDB
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Dexie.js
Dexie.js is a wrapper library for indexedDB - the standard database in the browser. http://dexie.org
Why?
Dexie solves three main issues with the native IndexedDB API:
- Ambivalent error handling
- Poor queries
- Code complexity
Dexie provides a neat database API with a well thought-through API design, robust error handling, extendability, change tracking awareness and extended KeyRange support (case insensitive search, set matches and OR operations).
Hello World
<!doctype html>
<html>
<head>
<script src="https://npmcdn.com/dexie@latest/dist/dexie.js"></script>
<script>
//
// Declare Database
//
var db = new Dexie("FriendDatabase");
db.version(1).stores({
friends: "++id,name,age"
});
//
// Manipulate and Query Database
//
db.friends.add({name: "Josephine", age: 21}).then(function() {
return db.friends.where("age").below(25).toArray();
}).then(function (youngFriends) {
alert ("My young friends: " + JSON.stringify(youngFriends));
}).catch(function (e) {
alert ("Error: " + (e.stack || e));
});
</script>
</head>
</html>
Yes, it's that simple.
Performance
Dexie has a kick-ass performance. It's bulk methods take advantage of a not well known feature in indexedDB that makes it possible to store stuff without listening to every onsuccess event. This speeds up the performance to a maximum.
Supported operations
above(key): Collection;
aboveOrEqual(key): Collection;
add(item, key?): Promise;
and(filter: (x) => boolean): Collection;
anyOf(keys[]): Collection;
anyOfIgnoreCase(keys: string[]): Collection;
below(key): Collection;
belowOrEqual(key): Collection;
between(lower, upper, includeLower?, includeUpper?): Collection;
bulkAdd(items: Array): Promise;
bulkDelete(keys: Array): Promise;
bulkPut(items: Array): Promise;
clear(): Promise;
count(): Promise;
delete(key): Promise;
distinct(): Collection;
each(callback: (obj) => any): Promise;
eachKey(callback: (key) => any): Promise;
eachPrimaryKey(callback: (key) => any): Promise;
eachUniqueKey(callback: (key) => any): Promise;
equals(key): Collection;
equalsIgnoreCase(key): Collection;
filter(fn: (obj) => boolean): Collection;
first(): Promise;
get(key): Promise;
inAnyRange(ranges): Collection;
keys(): Promise;
last(): Promise;
limit(n: number): Collection;
modify(changeCallback: (obj: T, ctx:{value: T}) => void): Promise;
modify(changes: { [keyPath: string]: any } ): Promise;
noneOf(keys: Array): Collection;
notEqual(key): Collection;
offset(n: number): Collection;
or(indexOrPrimayKey: string): WhereClause;
orderBy(index: string): Collection;
primaryKeys(): Promise;
put(item: T, key?: Key): Promise;
reverse(): Collection;
sortBy(keyPath: string): Promise;
startsWith(key: string): Collection;
startsWithAnyOf(prefixes: string[]): Collection;
startsWithAnyOfIgnoreCase(prefixes: string[]): Collection;
startsWithIgnoreCase(key: string): Collection;
toArray(): Promise;
toCollection(): Collection;
uniqueKeys(): Promise;
until(filter: (value) => boolean, includeStopEntry?: boolean): Collection;
update(key: Key, changes: { [keyPath: string]: any }): Promise;
This is a mix of methods from WhereClause, Table and Collection. Dive into the API reference to see the details.
Hello World (ES2015 / ES6)
This sample shows how to use Dexie with ES6 compliant environments and npm module resolution. With ES6, the yield
keyword can be used instead of calling .then()
on every database operation. The yield
keyword and generator functions are already supported today (March 2016) in Chrome, Firefox, Edge and Opera without a transpiler (though this example also uses import statements which still needs transpilation). Dive into this? Read SIMPLIFY WITH YIELD!
import Dexie from 'dexie';
//
// Declare Database
//
let db = new Dexie("FriendDatabase");
db.version(1).stores({ friends: "++id,name,age" });
//
// Have Fun
//
db.transaction('rw', db.friends, function*() {
// Make sure we have something in DB:
if ((yield db.friends.where('name').equals('Josephine').count()) === 0) {
let id = yield db.friends.add({name: "Josephine", age: 21});
alert (`Addded friend with id ${id}`);
}
// Query:
let youngFriends = yield db.friends.where("age").below(25).toArray();
// Show result:
alert ("My young friends: " + JSON.stringify(youngFriends));
}).catch(e => {
alert(e.stack || e);
});
NOTE: db.transaction() will treat generator functions (function * ) so that it is possible to use yield
for consuming promises. Yield can be used outside transactions as well.
Hello World (ES2016 / ES7)
import Dexie from 'dexie';
let Promise = Dexie.Promise; // KEEP! (*1)
//
// Declare Database
//
var db = new Dexie("FriendDatabase");
db.version(1).stores({ friends: "++id,name,age" });
db.transaction('rw', db.friends, async() => {
// Make sure we have something in DB:
if ((await db.friends.where('name').equals('Josephine').count()) === 0) {
let id = await db.friends.add({name: "Josephine", age: 21});
alert (`Addded friend with id ${id}`);
}
// Query:
let youngFriends = await db.friends.where("age").below(25).toArray();
// Show result:
alert ("My young friends: " + JSON.stringify(youngFriends));
}).catch(e => {
alert(e.stack || e);
});
*1: Makes it safe to use async / await within transactions. ES7 async keyword will take the Promise implementation of the current scope. Dexie.Promise can track transaction scopes, which is not possible with the standard Promise. This declaration needs only to be local to the scope where your async functions reside. If working with different promise implementations in the same module, declare your async functions in a block and put the declaration there { let Promise = Dexie.Promise; async function (){...} }
.
Hello World (Typescript)
import Dexie from 'dexie';
let Promise = Dexie.Promise; // KEEP! (See *1 above)
interface IFriend {
id?: number;
name?: string;
age?: number;
}
//
// Declare Database
//
class FriendDatabase extends Dexie {
friends: Dexie.Table<IFriend,number>;
constructor() {
super("FriendDatabase");
this.version(1).stores({
friends: "++id,name,age"
});
}
}
var db = new FriendDatabase();
db.transaction('rw', db.friends, async() => {
// Make sure we have something in DB:
if ((await db.friends.where('name').equals('Josephine').count()) === 0) {
let id = await db.friends.add({name: "Josephine", age: 21});
alert (`Addded friend with id ${id}`);
}
// Query:
let youngFriends = await db.friends.where("age").below(25).toArray();
// Show result:
alert ("My young friends: " + JSON.stringify(youngFriends));
}).catch(e => {
alert(e.stack || e);
});
Samples
https://github.com/dfahlander/Dexie.js/wiki/Samples
https://github.com/dfahlander/Dexie.js/tree/master/samples
Forum
https://groups.google.com/forum/#!forum/dexiejs
Website
Install over npm
npm install dexie
Download
For those who don't like package managers, here's the download links:
https://npmcdn.com/dexie/dist/dexie.min.js
https://npmcdn.com/dexie/dist/dexie.min.js.map
https://npmcdn.com/dexie/dist/dexie.d.ts
Contributing
Here is a little cheat-sheet for how to symlink your app's node_modules/dexie
to a place where you can edit the source, version control your changes and create pull requests back to Dexie. Assuming you've already ran npm install dexie --save
for the app your are developing.
Fork Dexie.js from the web gui on github
Clone your fork locally by launching a shell/command window and cd to a neutral place (like
~repos/
,c:\repos
or whatever)Run the following commands: (if you're on npm 2.x and Windows, you need to elevate your command prompt for
npm install
to succeed)git clone https://github.com/YOUR-USERNAME/Dexie.js.git cd Dexie.js npm install npm run build npm link
cd to your app directory and write:
npm link dexie
Your app's node_modules/dexie/
is now sym-linked to the Dexie.js clone on your hard drive so any change you do there will propagate to your app. Build dexie.js using npm run build
or npm run watch
. The latter will react on any source file change and rebuild the dist files.
That's it. Now you're up and running to test and commit changes to Dexie.js that will instantly affect the app you are developing.
Pull requests are more than welcome. Some advices are:
- Run npm test before making a pull request.
- If you find an issue, a unit test that reproduces it is lovely ;). If you don't know where to put it, put it in
test/tests-misc.js
. We use qunit. Just look at existing tests intests-misc.js
to see how they should be written. Tests are transpiled in the build script so you can use ES6 if you like.
Build
npm install (need to be elevated on windows for some reason)
npm run build
Test
npm test
Watch
npm run watch