twister-lib-js

A Twister Library in JavaScript

Scope of this Project

twister-lib-js handles all querying and manipulation of the Twister P2P network, given the availability of a (remote or local) twisterd JSON-RPC endpoint. This includes managing the network resource, by bundleing queries and by caching. This also includes the ability sign posts and to encrypt and decrypt direct messages locally.

twister-lib-js should be compilable for as many platforms as possible including:

• All popular Browsers (for web apps as well as firefoxOS)
• node-js (for server-side functionality)
• The iOS Javascript VM (for building native iOS apps)
• The Android Javascript VM (for building native android apps)

A techdemo of twister-lib-js combined with react-js can be found at http://github.com/Tschaul/twister-react

Implementation Status

Resource	query	manipulate (client side wallet)	manipulate (server side wallet)
Posts	✓	✓	✓
Replies	✓	✓	✓
Retwists	✓	✓	✓
Profile	✓	✓	✓
Avatar	✓	✓	✓
Followings	✓	✓	✓
Mentions	✓	✓	-
Hashtags	✓	✓	-
Promoted Posts	✓	-	-
Direct Messages	-	-	✓
Group Messages	-	-	-

Todo

Next Version

• Implement methods to create or import accounts.
• Implement group chats

At Some Point

• Implement bind-methods (e.g. bindProfile(...) ) that repeatedly queries the resource and invokes a callback function for every update.
• When posting a new resource revision (status, profile, avatar...) add the updated resource to the cache but flag it as "dirty" and rollback if the resource is not confirmed after a certain time.
• Implement get...Promise(...) functions (e.g. getProfilePromise(...) ) that work with https://github.com/yortus/asyncawait to avoid callback hells
• Implement code specific error functions (e.g. "errorfunc_32052" catches errors with code 32052)

Usage

In a Node Project

From inside the project folder run

npm install twister-lib-js

Then inside your code import the library using

Twister = require('twister-lib-js');

In a Webapp

Download the twister-lib.js file into you project folder. Link to it inside html using

<script src="path/to/twister-lib.js"></script>

Code Examples

Display the content of the latest post of user tschaul:

Twister.getUser("tschaul").doStatus(function(post){
  console.log(post.getContent());  
});

For more code examples in tutorial form, see /examples

Error Codes

twister-lib-js passes through all JSON-RPC errors. Internal errors are thrown in the same format with codes ranging between 32050 and 32099:

• 32050: DHT resource signature could not be verified.
• 32051: Unknown query setting was requested.
• 32052: DHT resource is empty. (Only thrown for status, post, profile and avatar resources.)
• 32060: Post signature could not be verified.
• 32061: Public key not available on server.
• 32062: Signature of retwisted post could not be verified.
• 32063: Post could not be decrypted.
• 32064: Private key is in conflict with public key.
• 32080: Unsupported wallet type.
• 32081: No wallet users found on the server.
• 32082: Torrent inactive. Activate torrent first!
• 32090: Host not reachable.
• 32091: Request was not processed successfully (http error: HTTP_ERROR_CODE).
• 32092: An error occurred while parsing the JSON response body.

Change Log

0.3.0

• New query setting queryId. Can be used to mark multiple queries with a common id. With the Twister.onQueryComplete(...) function a handler can be registered that is triggered when the last query is completed. see examples/021_deep_fetching.js

0.2.1

• Better handling of http/connection errors. Error codes: 32090-32092

0.2.0

• Resources can now remove themselves from the cache using their own trim() function.
• New function Twister.trimCache(timestamp) deletes every resource from the cache that is older than the timestamp, or has not been accessed since the timestamp. Needed to manage localStorage size in browsers.
• Resources with invalid signatures now get removed from the cache.