Dcshares websocket interface (dcsharesjs-ws)
Pure JavaScript Dcshares websocket library for node.js and browsers. Can be used to easily connect to and obtain data from the Dcshares blockchain via public apis or local nodes.
Credit for the original implementation goes to jcalfeee.
Setup
This library can be obtained through npm:
npm install dcsharesjs-ws
Usage
Several examples are available in the /examples folder, and the tests in /test also show how to use the library.
Browser bundles are provided in /build/, for testing purposes you can access this from rawgit:
<script type="text/javascript" src="https://cdn.rawgit.com/dcshares/dcsharesjs-ws/build/dcsharesjs-ws.js" />
A variable dcshares_ws will be available in window.
For use in a webpack/browserify context, see the example below for how to open a websocket connection to the Openledger API and subscribe to any object updates:
var {Apis} = require("dcsharesjs-ws");
Apis.instance("wss://dcshares.openledger.info/ws", true).init_promise.then((res) => {
console.log("connected to:", res[0].network);
Apis.instance().db_api().exec( "set_subscribe_callback", [ updateListener, true ] )
});
function updateListener(object) {
console.log("set_subscribe_callback:\n", object);
}
The set_subscribe_callback
callback (updateListener) will be called whenever an object on the blockchain changes or is removed. This is very powerful and can be used to listen to updates for specific accounts, assets or most anything else, as all state changes happen through object updates. Be aware though that you will receive quite a lot of data this way.
Witness node endpoints
This is a non-exhaustive list of endpoints available from the witness_node executable, which provides the API server of Dcshares.
database_api
https://github.com/dcshares/dcshares-core/blob/master/libraries/app/database_api.cpp
Usage examples
Apis.instance().db_api().exec(method, params)
Apis.instance().db_api().exec("get_objects, [["1.3.0", "2.0.0", "2.1.0"]])
Objects
Method Name | Params |
---|---|
get_objects | [array object_ids] |
Subscriptions
Method Name | Params |
---|---|
set_subscribe_callback | [function callback, bool notify_remove_create] |
set_pending_transaction_callback | [function callback] |
set_block_applied_callback | [function callback] |
cancel_all_subscriptions | [] |
Blocks and transactions
Method Name | Params |
---|---|
get_block_header | [int block_num] |
get_block_header_batch | [array block_nums] |
get_block | [int block_num] |
get_transaction | [int block_num, int trx_in_block] |
Globals
Method Name | Params |
---|---|
get_chain_properties | [] |
get_global_properties | [] |
get_config | [] |
get_chain_id | [] |
get_dynamic_global_properties | [] |
Keys
Method Name | Params |
---|---|
get_key_references | [array public_keys] |
is_public_key_registered | [string public_key] |
Accounts
Method Name | Params |
---|---|
get_accounts | [array account_ids] |
get_full_accounts | [array account_names_or_ids, bool subscribe] |
get_account_by_name | [string name] |
get_account_references | [string account_id] |
lookup_account_names | [array account_names] |
lookup_accounts | [string lower_bound_name, int limit] |
get_account_count | [] |
Assets
Method Name | Params |
---|---|
get_assets | [array asset_ids] |
list_assets | [string lower_bound_symbol, int limit] |
lookup_asset_symbols | [array symbols_or_ids] |
Markets / feeds
Method Name | Params |
---|---|
get_limit_orders | [string asset_id_a, string asset_id_b, int limit] |
get_call_orders | [string asset_id, int limit] |
get_settle_orders | [string asset_id, int limit] |
get_margin_positions | [string account_id] |
subscribe_to_market | [function callback, string asset_id_a, string asset_id_b] |
unsubscribe_from_market | [string asset_id_a, string asset_id_b] |
get_ticker | [string base, string quote] |
get_24_volume | [string base, string quote] |
get_order_book | [string base, string quote, int limit] |
get_trade_history | [string base, string quote, date start, date stop, int limit] |
Tests
The tests show several use cases, to run, simply type npm run test
. The tests require a local witness node to be running, as well as an active internet connection.