Files
api/docs/api/index.html
T
2019-01-23 17:00:13 +00:00

2288 lines
65 KiB
HTML

<!DOCTYPE HTML>
<html lang="" >
<head>
<meta charset="UTF-8">
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<title>api · Polkadot API Book</title>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="description" content="">
<meta name="generator" content="GitBook 3.2.3">
<link rel="stylesheet" href="../gitbook/style.css">
<link rel="stylesheet" href="../gitbook/gitbook-plugin-insert-logo-link/plugin.css">
<link rel="stylesheet" href="../gitbook/gitbook-plugin-mermaid-gb3/mermaid/mermaid.css">
<link rel="stylesheet" href="../gitbook/gitbook-plugin-sunlight-highlighter/sunlight.css">
<link rel="stylesheet" href="../gitbook/gitbook-plugin-search/search.css">
<link rel="stylesheet" href="../gitbook/gitbook-plugin-fontsettings/website.css">
<link rel="stylesheet" href="../styles/website.css">
<meta name="HandheldFriendly" content="true"/>
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
<meta name="apple-mobile-web-app-capable" content="yes">
<meta name="apple-mobile-web-app-status-bar-style" content="black">
<link rel="apple-touch-icon-precomposed" sizes="152x152" href="../gitbook/images/apple-touch-icon-precomposed-152.png">
<link rel="shortcut icon" href="../gitbook/images/favicon.ico" type="image/x-icon">
<link rel="next" href="classes/_promise_index_.apipromise.html" />
<link rel="prev" href="../" />
</head>
<body>
<div class="book">
<div class="book-summary">
<div id="book-search-input" role="search">
<input type="text" placeholder="Type to search" />
</div>
<nav role="navigation">
<ul class="summary">
<li class="header">Packages</li>
<li class="chapter " data-level="1.1" data-path="../">
<a href="../">
Introduction
</a>
</li>
<li class="chapter active" data-level="1.2" data-path="./">
<a href="./">
api
</a>
<ul class="articles">
<li class="chapter " data-level="1.2.1" data-path="classes/_promise_index_.apipromise.html">
<a href="classes/_promise_index_.apipromise.html">
ApiPromise
</a>
</li>
<li class="chapter " data-level="1.2.2" data-path="classes/_rx_index_.apirx.html">
<a href="classes/_rx_index_.apirx.html">
ApiRx
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="1.3" data-path="../rpc-provider/">
<a href="../rpc-provider/">
rpc-provider
</a>
<ul class="articles">
<li class="chapter " data-level="1.3.1" data-path="../rpc-provider/classes/_http_index_.httpprovider.html">
<a href="../rpc-provider/classes/_http_index_.httpprovider.html">
HttpProvider
</a>
</li>
<li class="chapter " data-level="1.3.2" data-path="../rpc-provider/classes/_ws_index_.wsprovider.html">
<a href="../rpc-provider/classes/_ws_index_.wsprovider.html">
WsProvider
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="1.4" data-path="../types/">
<a href="../types/">
types (codec implementation)
</a>
</li>
<li class="header">Interfaces</li>
<li class="chapter " data-level="2.1" data-path="../METHODS_RPC.html">
<a href="../METHODS_RPC.html">
RPC
</a>
</li>
<li class="chapter " data-level="2.2" data-path="../METHODS_STORAGE.html">
<a href="../METHODS_STORAGE.html">
Chain state (runtime)
</a>
</li>
<li class="chapter " data-level="2.3" data-path="../METHODS_EXTRINSICS.html">
<a href="../METHODS_EXTRINSICS.html">
Extrinsics (runtime)
</a>
</li>
<li class="chapter " data-level="2.4" data-path="../METHODS_EVENTS.html">
<a href="../METHODS_EVENTS.html">
Events (runtime)
</a>
</li>
<li class="header">Examples</li>
<li class="chapter " data-level="3.1" data-path="../examples/promise/">
<a href="../examples/promise/">
ApiPromise
</a>
<ul class="articles">
<li class="chapter " data-level="3.1.1" data-path="../examples/promise/01_simple_connect/">
<a href="../examples/promise/01_simple_connect/">
Simple connect
</a>
</li>
<li class="chapter " data-level="3.1.2" data-path="../examples/promise/02_listen_to_blocks/">
<a href="../examples/promise/02_listen_to_blocks/">
Listen to blocks
</a>
</li>
<li class="chapter " data-level="3.1.3" data-path="../examples/promise/03_listen_to_balance_change/">
<a href="../examples/promise/03_listen_to_balance_change/">
Listen to balance change
</a>
</li>
<li class="chapter " data-level="3.1.4" data-path="../examples/promise/04_unsubscribe/">
<a href="../examples/promise/04_unsubscribe/">
Unsubscribe from listening
</a>
</li>
<li class="chapter " data-level="3.1.5" data-path="../examples/promise/05_read_storage/">
<a href="../examples/promise/05_read_storage/">
Read chain state
</a>
</li>
<li class="chapter " data-level="3.1.6" data-path="../examples/promise/06_make_transfer/">
<a href="../examples/promise/06_make_transfer/">
Make a transfer
</a>
</li>
<li class="chapter " data-level="3.1.7" data-path="../examples/promise/08_system_events/">
<a href="../examples/promise/08_system_events/">
Display system events
</a>
</li>
<li class="chapter " data-level="3.1.8" data-path="../examples/promise/09_transfer_events/">
<a href="../examples/promise/09_transfer_events/">
Transaction with events
</a>
</li>
<li class="chapter " data-level="3.1.9" data-path="../examples/promise/10_upgrade_chain/">
<a href="../examples/promise/10_upgrade_chain/">
Upgrade via sudo
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="3.2" data-path="../examples/rx/">
<a href="../examples/rx/">
ApiRx
</a>
<ul class="articles">
<li class="chapter " data-level="3.2.1" data-path="../examples/rx/01_simple_connect/">
<a href="../examples/rx/01_simple_connect/">
Simple connect
</a>
</li>
<li class="chapter " data-level="3.2.2" data-path="../examples/rx/02_listen_to_blocks/">
<a href="../examples/rx/02_listen_to_blocks/">
Listen to blocks
</a>
</li>
<li class="chapter " data-level="3.2.3" data-path="../examples/rx/03_listen_to_balance_change/">
<a href="../examples/rx/03_listen_to_balance_change/">
Listen to balance change
</a>
</li>
<li class="chapter " data-level="3.2.4" data-path="../examples/rx/04_unsubscribe/">
<a href="../examples/rx/04_unsubscribe/">
Unsubscribe from listening
</a>
</li>
<li class="chapter " data-level="3.2.5" data-path="../examples/rx/05_read_storage/">
<a href="../examples/rx/05_read_storage/">
Read chain state
</a>
</li>
<li class="chapter " data-level="3.2.6" data-path="../examples/rx/06_make_transfer/">
<a href="../examples/rx/06_make_transfer/">
Make a transfer
</a>
</li>
<li class="chapter " data-level="3.2.7" data-path="../examples/rx/08_system_events/">
<a href="../examples/rx/08_system_events/">
Display system events
</a>
</li>
<li class="chapter " data-level="3.2.8" data-path="../examples/rx/09_transfer_events/">
<a href="../examples/rx/09_transfer_events/">
Transaction with events
</a>
</li>
<li class="chapter " data-level="3.2.9" data-path="../examples/rx/10_upgrade_chain/">
<a href="../examples/rx/10_upgrade_chain/">
Upgrade via sudo
</a>
</li>
</ul>
</li>
<li class="divider"></li>
<li class="chapter " data-level="4.1" data-path="../types/classes/_accountid_.accountid.html">
<a href="../types/classes/_accountid_.accountid.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.2" data-path="../types/classes/_accountindex_.accountindex.html">
<a href="../types/classes/_accountindex_.accountindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.3" data-path="../types/classes/_address_.address.html">
<a href="../types/classes/_address_.address.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.4" data-path="../types/classes/_authorityid_.authorityid.html">
<a href="../types/classes/_authorityid_.authorityid.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.5" data-path="../types/classes/_balance_.balance.html">
<a href="../types/classes/_balance_.balance.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.6" data-path="../types/classes/_bft_.bftauthoritysignature.html">
<a href="../types/classes/_bft_.bftauthoritysignature.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.7" data-path="../types/classes/_bft_.bfthashsignature.html">
<a href="../types/classes/_bft_.bfthashsignature.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.8" data-path="../types/classes/_block_.block.html">
<a href="../types/classes/_block_.block.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.9" data-path="../types/classes/_blocknumber_.blocknumber.html">
<a href="../types/classes/_blocknumber_.blocknumber.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.10" data-path="../types/classes/_bool_.bool.html">
<a href="../types/classes/_bool_.bool.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.11" data-path="../types/classes/_bytes_.bytes.html">
<a href="../types/classes/_bytes_.bytes.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.12" data-path="../types/classes/_chainproperties_.chainproperties.html">
<a href="../types/classes/_chainproperties_.chainproperties.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.13" data-path="../types/classes/_codec_base_.base.html">
<a href="../types/classes/_codec_base_.base.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.14" data-path="../types/classes/_codec_compact_.compact.html">
<a href="../types/classes/_codec_compact_.compact.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.15" data-path="../types/classes/_codec_enum_.enum.html">
<a href="../types/classes/_codec_enum_.enum.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.16" data-path="../types/classes/_codec_enumtype_.enumtype.html">
<a href="../types/classes/_codec_enumtype_.enumtype.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.17" data-path="../types/classes/_codec_option_.option.html">
<a href="../types/classes/_codec_option_.option.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.18" data-path="../types/classes/_codec_set_.set.html">
<a href="../types/classes/_codec_set_.set.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.19" data-path="../types/classes/_codec_struct_.struct.html">
<a href="../types/classes/_codec_struct_.struct.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.20" data-path="../types/classes/_codec_tuple_.tuple.html">
<a href="../types/classes/_codec_tuple_.tuple.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.21" data-path="../types/classes/_codec_typeregistry_.typeregistry.html">
<a href="../types/classes/_codec_typeregistry_.typeregistry.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.22" data-path="../types/classes/_codec_u8a_.u8a.html">
<a href="../types/classes/_codec_u8a_.u8a.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.23" data-path="../types/classes/_codec_u8afixed_.u8afixed.html">
<a href="../types/classes/_codec_u8afixed_.u8afixed.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.24" data-path="../types/classes/_codec_uint_.uint.html">
<a href="../types/classes/_codec_uint_.uint.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.25" data-path="../types/classes/_codec_vector_.vector.html">
<a href="../types/classes/_codec_vector_.vector.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.26" data-path="../types/classes/_data_.data.html">
<a href="../types/classes/_data_.data.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.27" data-path="../types/classes/_digest_.authoritieschange.html">
<a href="../types/classes/_digest_.authoritieschange.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.28" data-path="../types/classes/_digest_.changestrieroot.html">
<a href="../types/classes/_digest_.changestrieroot.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.29" data-path="../types/classes/_digest_.digest.html">
<a href="../types/classes/_digest_.digest.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.30" data-path="../types/classes/_digest_.digestitem.html">
<a href="../types/classes/_digest_.digestitem.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.31" data-path="../types/classes/_digest_.other.html">
<a href="../types/classes/_digest_.other.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.32" data-path="../types/classes/_digest_.seal.html">
<a href="../types/classes/_digest_.seal.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.33" data-path="../types/classes/_event_.event.html">
<a href="../types/classes/_event_.event.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.34" data-path="../types/classes/_event_.eventdata.html">
<a href="../types/classes/_event_.eventdata.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.35" data-path="../types/classes/_event_.eventindex.html">
<a href="../types/classes/_event_.eventindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.36" data-path="../types/classes/_eventrecord_.applyextrinsic.html">
<a href="../types/classes/_eventrecord_.applyextrinsic.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.37" data-path="../types/classes/_eventrecord_.eventrecord.html">
<a href="../types/classes/_eventrecord_.eventrecord.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.38" data-path="../types/classes/_eventrecord_.finalization.html">
<a href="../types/classes/_eventrecord_.finalization.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.39" data-path="../types/classes/_eventrecord_.phase.html">
<a href="../types/classes/_eventrecord_.phase.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.40" data-path="../types/classes/_extrinsic_.extrinsic.html">
<a href="../types/classes/_extrinsic_.extrinsic.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.41" data-path="../types/classes/_extrinsicera_.extrinsicera.html">
<a href="../types/classes/_extrinsicera_.extrinsicera.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.42" data-path="../types/classes/_extrinsics_.extrinsics.html">
<a href="../types/classes/_extrinsics_.extrinsics.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.43" data-path="../types/classes/_extrinsicsignature_.extrinsicsignature.html">
<a href="../types/classes/_extrinsicsignature_.extrinsicsignature.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.44" data-path="../types/classes/_extrinsicstatus_.broadcast.html">
<a href="../types/classes/_extrinsicstatus_.broadcast.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.45" data-path="../types/classes/_extrinsicstatus_.dropped.html">
<a href="../types/classes/_extrinsicstatus_.dropped.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.46" data-path="../types/classes/_extrinsicstatus_.extrinsicstatus.html">
<a href="../types/classes/_extrinsicstatus_.extrinsicstatus.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.47" data-path="../types/classes/_extrinsicstatus_.finalised.html">
<a href="../types/classes/_extrinsicstatus_.finalised.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.48" data-path="../types/classes/_extrinsicstatus_.usurped.html">
<a href="../types/classes/_extrinsicstatus_.usurped.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.49" data-path="../types/classes/_gas_.gas.html">
<a href="../types/classes/_gas_.gas.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.50" data-path="../types/classes/_h256_.h256.html">
<a href="../types/classes/_h256_.h256.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.51" data-path="../types/classes/_h512_.h512.html">
<a href="../types/classes/_h512_.h512.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.52" data-path="../types/classes/_hash_.hash.html">
<a href="../types/classes/_hash_.hash.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.53" data-path="../types/classes/_header_.header.html">
<a href="../types/classes/_header_.header.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.54" data-path="../types/classes/_justification_.justification.html">
<a href="../types/classes/_justification_.justification.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.55" data-path="../types/classes/_justification_.rhdjustification.html">
<a href="../types/classes/_justification_.rhdjustification.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.56" data-path="../types/classes/_keyvalue_.keyvalue.html">
<a href="../types/classes/_keyvalue_.keyvalue.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.57" data-path="../types/classes/_keyvalue_.keyvalueoption.html">
<a href="../types/classes/_keyvalue_.keyvalueoption.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.58" data-path="../types/classes/_metadata_.callmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.59" data-path="../types/classes/_metadata_.eventmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.60" data-path="../types/classes/_metadata_.functionargumentmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.61" data-path="../types/classes/_metadata_.functionmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.62" data-path="../types/classes/_metadata_.modulemetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.63" data-path="../types/classes/_metadata_.outerdispatchcall.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.64" data-path="../types/classes/_metadata_.outerdispatchmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.65" data-path="../types/classes/_metadata_.outereventmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.66" data-path="../types/classes/_metadata_.outereventmetadataevent.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.67" data-path="../types/classes/_metadata_.runtimemetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.68" data-path="../types/classes/_metadata_.runtimemodulemetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.69" data-path="../types/classes/_metadata_.storagefunctionmetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.70" data-path="../types/classes/_metadata_.storagefunctionmodifier.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.71" data-path="../types/classes/_metadata_.storagefunctiontype.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.72" data-path="../types/classes/_metadata_.storagefunctiontype_map.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.73" data-path="../types/classes/_metadata_.storagemetadata.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.74" data-path="../types/classes/_method_.method.html">
<a href="../types/classes/_method_.method.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.75" data-path="../types/classes/_method_.methodindex.html">
<a href="../types/classes/_method_.methodindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.76" data-path="../types/classes/_misbehaviorreport_.bftatreport.html">
<a href="../types/classes/_misbehaviorreport_.bftatreport.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.77" data-path="../types/classes/_misbehaviorreport_.bftdoublecommit.html">
<a href="../types/classes/_misbehaviorreport_.bftdoublecommit.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.78" data-path="../types/classes/_misbehaviorreport_.bftdoubleprepare.html">
<a href="../types/classes/_misbehaviorreport_.bftdoubleprepare.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.79" data-path="../types/classes/_misbehaviorreport_.bftdoublepropose.html">
<a href="../types/classes/_misbehaviorreport_.bftdoublepropose.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.80" data-path="../types/classes/_misbehaviorreport_.bftproposeoutofturn.html">
<a href="../types/classes/_misbehaviorreport_.bftproposeoutofturn.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.81" data-path="../types/classes/_misbehaviorreport_.misbehaviorkind.html">
<a href="../types/classes/_misbehaviorreport_.misbehaviorkind.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.82" data-path="../types/classes/_misbehaviorreport_.misbehaviorreport.html">
<a href="../types/classes/_misbehaviorreport_.misbehaviorreport.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.83" data-path="../types/classes/_moment_.moment.html">
<a href="../types/classes/_moment_.moment.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.84" data-path="../types/classes/_newaccountoutcome_.newaccountoutcome.html">
<a href="../types/classes/_newaccountoutcome_.newaccountoutcome.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.85" data-path="../types/classes/_nonce_.nonce.html">
<a href="../types/classes/_nonce_.nonce.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.86" data-path="../types/classes/_null_.null.html">
<a href="../types/classes/_null_.null.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.87" data-path="../types/classes/_origin_.origin.html">
<a href="../types/classes/_origin_.origin.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.88" data-path="../types/classes/_parachainid_.parachainid.md">
<span>
hidden
</a>
</li>
<li class="chapter " data-level="4.89" data-path="../types/classes/_pendingextrinsics_.pendingextrinsics.html">
<a href="../types/classes/_pendingextrinsics_.pendingextrinsics.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.90" data-path="../types/classes/_perbill_.perbill.html">
<a href="../types/classes/_perbill_.perbill.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.91" data-path="../types/classes/_permill_.permill.html">
<a href="../types/classes/_permill_.permill.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.92" data-path="../types/classes/_propindex_.propindex.html">
<a href="../types/classes/_propindex_.propindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.93" data-path="../types/classes/_proposal_.proposal.html">
<a href="../types/classes/_proposal_.proposal.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.94" data-path="../types/classes/_proposalindex_.proposalindex.html">
<a href="../types/classes/_proposalindex_.proposalindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.95" data-path="../types/classes/_referendumindex_.referendumindex.html">
<a href="../types/classes/_referendumindex_.referendumindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.96" data-path="../types/classes/_runtimeversion_.apiid.html">
<a href="../types/classes/_runtimeversion_.apiid.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.97" data-path="../types/classes/_runtimeversion_.runtimeversion.html">
<a href="../types/classes/_runtimeversion_.runtimeversion.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.98" data-path="../types/classes/_runtimeversion_.runtimeversionapi.html">
<a href="../types/classes/_runtimeversion_.runtimeversionapi.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.99" data-path="../types/classes/_sessionkey_.sessionkey.html">
<a href="../types/classes/_sessionkey_.sessionkey.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.100" data-path="../types/classes/_signature_.signature.html">
<a href="../types/classes/_signature_.signature.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.101" data-path="../types/classes/_signaturepayload_.signaturepayload.html">
<a href="../types/classes/_signaturepayload_.signaturepayload.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.102" data-path="../types/classes/_signedblock_.signedblock.html">
<a href="../types/classes/_signedblock_.signedblock.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.103" data-path="../types/classes/_storagechangeset_.storagechangeset.html">
<a href="../types/classes/_storagechangeset_.storagechangeset.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.104" data-path="../types/classes/_storagedata_.storagedata.html">
<a href="../types/classes/_storagedata_.storagedata.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.105" data-path="../types/classes/_storagekey_.storagekey.html">
<a href="../types/classes/_storagekey_.storagekey.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.106" data-path="../types/classes/_storedpendingchange_.nextauthority.html">
<a href="../types/classes/_storedpendingchange_.nextauthority.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.107" data-path="../types/classes/_storedpendingchange_.storedpendingchange.html">
<a href="../types/classes/_storedpendingchange_.storedpendingchange.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.108" data-path="../types/classes/_text_.text.html">
<a href="../types/classes/_text_.text.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.109" data-path="../types/classes/_type_.type.html">
<a href="../types/classes/_type_.type.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.110" data-path="../types/classes/_u128_.u128.html">
<a href="../types/classes/_u128_.u128.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.111" data-path="../types/classes/_u16_.u16.html">
<a href="../types/classes/_u16_.u16.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.112" data-path="../types/classes/_u256_.u256.html">
<a href="../types/classes/_u256_.u256.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.113" data-path="../types/classes/_u32_.u32.html">
<a href="../types/classes/_u32_.u32.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.114" data-path="../types/classes/_u64_.u64.html">
<a href="../types/classes/_u64_.u64.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.115" data-path="../types/classes/_u8_.u8.html">
<a href="../types/classes/_u8_.u8.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.116" data-path="../types/classes/_validatorprefs_.validatorprefs.html">
<a href="../types/classes/_validatorprefs_.validatorprefs.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.117" data-path="../types/classes/_voteindex_.voteindex.html">
<a href="../types/classes/_voteindex_.voteindex.html">
hidden
</a>
</li>
<li class="chapter " data-level="4.118" data-path="../types/classes/_votethreshold_.votethreshold.html">
<a href="../types/classes/_votethreshold_.votethreshold.html">
hidden
</a>
</li>
<li class="divider"></li>
<li>
<a href="https://www.gitbook.com" target="blank" class="gitbook-link">
Published with GitBook
</a>
</li>
</ul>
</nav>
</div>
<div class="book-body">
<div class="body-inner">
<div class="book-header" role="navigation">
<!-- Title -->
<h1>
<i class="fa fa-circle-o-notch fa-spin"></i>
<a href=".." >api</a>
</h1>
</div>
<div class="page-wrapper" tabindex="-1" role="main">
<div class="page-inner">
<div id="book-search-results">
<div class="search-noresults">
<section class="normal markdown-section">
<h1 id="polkadotapi">@polkadot/api</h1>
<p>The Polkadot-JS API provides easy-to-use wrappers around JSONRPC calls that flow from an application to a node. It handles all the encoding and decoding or parameters, provides access to RPC functions and allows for the query of chain state and the submission of transactions.</p>
<p>The API wrappers provide a standard interface for use -</p>
<ul>
<li>A static <code>.create(&lt;optional WsProvider&gt;)</code> that returns an API instance when connected, decorated and ready-to use</li>
<li>The above is just a wrapper for <code>new Api(&lt;optional WsProvider&gt;)</code>, exposing the <code>isReady</code> getter</li>
<li><code>api.rpc.&lt;section&gt;.&lt;method&gt;</code> provides access to actual RPC calls, be it for queries, submission or retrieving chain information<ul>
<li><a href="../METHODS_RPC.html">RPC (node interface)</a></li>
</ul>
</li>
<li><code>api.query.&lt;section&gt;.&lt;method&gt;</code> provides access to chain state queries. These are dynamically populated based on what the runtime provides<ul>
<li><a href="../METHODS_STORAGE.html">Storage chain state (runtime node interface)</a></li>
</ul>
</li>
<li><code>api.tx.&lt;section&gt;.&lt;method&gt;</code> provides the ability to create a transaction, like chain state, this list is populated from a runtime query<ul>
<li><a href="../METHODS_EXTRINSICS.html">Extrinsics (runtime node interface)</a></li>
</ul>
</li>
</ul>
<h2 id="api-selection">API Selection</h2>
<p>There are two flavours of the API provided, one allowing a standard interface via JavaScript Promises and the second provides an Observable wrapper using <a href="https://github.com/ReactiveX/rxjs" target="_blank">RxJS</a>. Depending on your use-case and familiarity, you can choose either (or even both) for your application.</p>
<ul>
<li><a href="classes/_promise_index_.apipromise.html">ApiPromise</a> All interface calls returns Promises, including the static <code>.create(...)</code>. Additionally any subscription method uses <code>(value) =&gt; {}</code> callbacks, returning the value as the subscription is updated.</li>
<li><a href="classes/_rx_index_.apirx.html">ApiRx</a> All interface calls return RxJS Observables, including the static <code>.create(...)</code>. In the same fashion subscription-based methods return long-running Observables that update with the latest values.</li>
</ul>
<h2 id="dynamic-by-default">Dynamic by default</h2>
<p>Substrate (upon which Polkadot is built) uses on-chain WASM runtimes, allowing for upgradability. Each runtime defining the actual chain extrinsics (submitted transactions and block intrinsics) as well as available entries in the chain state. Due to this, the API endpoints for queries and transactions are dynamically populated from the running chain.</p>
<p>Due to this dynamic nature, this API departs from traditional APIs which only has fixed endpoints, driving use by what is available by the runtime. As a start, this generic nature has a learning curve, although the provided documentation, examples and linked documentation tries to make that experience as seamless as possible.</p>
<h2 id="installation--import">Installation &amp; import</h2>
<p>Installation -</p>
<pre><code>npm install --save @polkadot/api
</code></pre><p>Subscribing to blocks via Promise-based API -</p>
<pre><code class="lang-javascript"><div class="sunlight-container sunlight-theme-gitbook"><div class="sunlight-code-container"><pre class="sunlight-highlight-javascript sunlight-highlighted"><span class="sunlight-javascript"><span class="sunlight-reservedWord">import</span>&#xA0;<span class="sunlight-punctuation">{</span>&#xA0;<span class="sunlight-ident">ApiPromise</span>&#xA0;<span class="sunlight-punctuation">}</span>&#xA0;<span class="sunlight-ident">from</span>&#xA0;<span class="sunlight-string">&apos;@polkadot/api&apos;</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-comment">//&#xA0;initialise&#xA0;via&#xA0;static&#xA0;create</span>
<span class="sunlight-reservedWord">const</span>&#xA0;<span class="sunlight-ident">api</span>&#xA0;<span class="sunlight-operator">=</span>&#xA0;<span class="sunlight-ident">await</span>&#xA0;<span class="sunlight-ident">ApiPromise</span><span class="sunlight-operator">.</span><span class="sunlight-ident">create</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-comment">//&#xA0;make&#xA0;a&#xA0;call&#xA0;to&#xA0;retrieve&#xA0;the&#xA0;current&#xA0;network&#xA0;head</span>
<span class="sunlight-ident">api</span><span class="sunlight-operator">.</span><span class="sunlight-ident">rpc</span><span class="sunlight-operator">.</span><span class="sunlight-ident">chain</span><span class="sunlight-operator">.</span><span class="sunlight-ident">subscribeNewHead</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">(</span><span class="sunlight-ident">header</span><span class="sunlight-punctuation">)</span>&#xA0;<span class="sunlight-operator">=</span><span class="sunlight-operator">&gt;</span>&#xA0;<span class="sunlight-punctuation">{</span>
&#xA0;&#xA0;<span class="sunlight-ident">console</span><span class="sunlight-operator">.</span><span class="sunlight-ident">log</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">`</span><span class="sunlight-ident">Chain</span>&#xA0;<span class="sunlight-ident">is</span>&#xA0;<span class="sunlight-ident">at</span>&#xA0;<span class="sunlight-punctuation">#</span><span class="sunlight-ident">$</span><span class="sunlight-punctuation">{</span><span class="sunlight-ident">header</span><span class="sunlight-operator">.</span><span class="sunlight-ident">blockNumber</span><span class="sunlight-punctuation">}</span><span class="sunlight-punctuation">`</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-punctuation">}</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
</span></pre></div></div></code></pre>
<p>Subscribing to blocks via RxJS-based API -</p>
<pre><code class="lang-javascript"><div class="sunlight-container sunlight-theme-gitbook"><div class="sunlight-code-container"><pre class="sunlight-highlight-javascript sunlight-highlighted"><span class="sunlight-javascript"><span class="sunlight-reservedWord">import</span>&#xA0;<span class="sunlight-punctuation">{</span>&#xA0;<span class="sunlight-ident">ApiRx</span>&#xA0;<span class="sunlight-punctuation">}</span>&#xA0;<span class="sunlight-ident">from</span>&#xA0;<span class="sunlight-string">&apos;@polkadot/api&apos;</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-comment">//&#xA0;initialise&#xA0;via&#xA0;static&#xA0;create</span>
<span class="sunlight-reservedWord">const</span>&#xA0;<span class="sunlight-ident">api</span>&#xA0;<span class="sunlight-operator">=</span>&#xA0;<span class="sunlight-ident">await</span>&#xA0;<span class="sunlight-ident">ApiRx</span><span class="sunlight-operator">.</span><span class="sunlight-ident">create</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">)</span><span class="sunlight-operator">.</span><span class="sunlight-ident">toPromise</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-comment">//&#xA0;make&#xA0;a&#xA0;call&#xA0;to&#xA0;retrieve&#xA0;the&#xA0;current&#xA0;network&#xA0;head</span>
<span class="sunlight-ident">api</span><span class="sunlight-operator">.</span><span class="sunlight-ident">rpc</span><span class="sunlight-operator">.</span><span class="sunlight-ident">chain</span><span class="sunlight-operator">.</span><span class="sunlight-ident">subscribeNewHead</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">)</span><span class="sunlight-operator">.</span><span class="sunlight-ident">subscribe</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">(</span><span class="sunlight-ident">header</span><span class="sunlight-punctuation">)</span>&#xA0;<span class="sunlight-operator">=</span><span class="sunlight-operator">&gt;</span>&#xA0;<span class="sunlight-punctuation">{</span>
&#xA0;&#xA0;<span class="sunlight-ident">console</span><span class="sunlight-operator">.</span><span class="sunlight-ident">log</span><span class="sunlight-punctuation">(</span><span class="sunlight-punctuation">`</span><span class="sunlight-ident">Chain</span>&#xA0;<span class="sunlight-ident">is</span>&#xA0;<span class="sunlight-ident">at</span>&#xA0;<span class="sunlight-punctuation">#</span><span class="sunlight-ident">$</span><span class="sunlight-punctuation">{</span><span class="sunlight-ident">header</span><span class="sunlight-operator">.</span><span class="sunlight-ident">blockNumber</span><span class="sunlight-punctuation">}</span><span class="sunlight-punctuation">`</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
<span class="sunlight-punctuation">}</span><span class="sunlight-punctuation">)</span><span class="sunlight-punctuation">;</span>
</span></pre></div></div></code></pre>
<h2 id="users">Users</h2>
<p>Some of the users of the API (let us know if you are missing from the list), include -</p>
<ul>
<li><a href="https://github.com/polkadot-js/apps" target="_blank">Polkadot-JS UI</a> A user-interface that allows you to make transactions, query the network or participate in actions on the network such as referendums and staking</li>
<li><a href="https://gitlab.com/Polkabot" target="_blank">Polkabot</a> Polkabot is a Matrix chatbot that keeps an eye on the Polkadot network. You can see Polkabot in action in <a href="https://matrix.to/#/#polkadot-network-status:matrix.org" target="_blank">https://matrix.to/#/#polkadot-network-status:matrix.org</a></li>
</ul>
</section>
</div>
<div class="search-results">
<div class="has-results">
<h1 class="search-results-title"><span class='search-results-count'></span> results matching "<span class='search-query'></span>"</h1>
<ul class="search-results-list"></ul>
</div>
<div class="no-results">
<h1 class="search-results-title">No results matching "<span class='search-query'></span>"</h1>
</div>
</div>
</div>
</div>
</div>
</div>
<a href="../" class="navigation navigation-prev " aria-label="Previous page: Introduction">
<i class="fa fa-angle-left"></i>
</a>
<a href="classes/_promise_index_.apipromise.html" class="navigation navigation-next " aria-label="Next page: ApiPromise">
<i class="fa fa-angle-right"></i>
</a>
</div>
<script>
var gitbook = gitbook || [];
gitbook.push(function() {
gitbook.page.hasChanged({"page":{"title":"api","level":"1.2","depth":1,"next":{"title":"ApiPromise","level":"1.2.1","depth":2,"path":"api/classes/_promise_index_.apipromise.md","ref":"api/classes/_promise_index_.apipromise.md","articles":[]},"previous":{"title":"Introduction","level":"1.1","depth":1,"path":"README.md","ref":"README.md","articles":[]},"dir":"ltr"},"config":{"plugins":["include-codeblock","insert-logo-link","mermaid-gb3","-highlight","sunlight-highlighter"],"root":"docs","styles":{"website":"styles/website.css"},"pluginsConfig":{"insert-logo-link":{"src":"/api/logo.png","url":"https://polkadot.js.org"},"search":{},"lunr":{"maxIndexSize":1000000,"ignoreSpecialCharacters":false},"fontsettings":{"theme":"white","family":"sans","size":2},"mermaid-gb3":{},"include-codeblock":{"check":false,"edit":false,"lang":"","fixlang":false,"template":"default","theme":"chrome","unindent":false},"sharing":{"facebook":true,"twitter":true,"google":false,"weibo":false,"instapaper":false,"vk":false,"all":["facebook","google","twitter","weibo","instapaper"]},"theme-default":{"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"showLevel":false},"sunlight-highlighter":{"theme":"gitbook","lineNumbers":false}},"theme":"default","pdf":{"pageNumbers":true,"fontSize":12,"fontFamily":"Arial","paperSize":"a4","chapterMark":"pagebreak","pageBreaksBefore":"/","margin":{"right":62,"left":62,"top":56,"bottom":56}},"structure":{"langs":"LANGS.md","readme":"README.md","glossary":"GLOSSARY.md","summary":"SUMMARY.md"},"variables":{},"title":"Polkadot API Book","gitbook":">=2.4.0"},"file":{"path":"api/README.md","mtime":"2019-01-23T16:58:08.036Z","type":"markdown"},"gitbook":{"version":"3.2.3","time":"2019-01-23T16:59:32.788Z"},"basePath":"..","book":{"language":""}});
});
</script>
</div>
<script src="../gitbook/gitbook.js"></script>
<script src="../gitbook/theme.js"></script>
<script src="../gitbook/gitbook-plugin-insert-logo-link/plugin.js"></script>
<script src="../gitbook/gitbook-plugin-mermaid-gb3/book/plugin.js"></script>
<script src="../gitbook/gitbook-plugin-search/search-engine.js"></script>
<script src="../gitbook/gitbook-plugin-search/search.js"></script>
<script src="../gitbook/gitbook-plugin-lunr/lunr.min.js"></script>
<script src="../gitbook/gitbook-plugin-lunr/search-lunr.js"></script>
<script src="../gitbook/gitbook-plugin-sharing/buttons.js"></script>
<script src="../gitbook/gitbook-plugin-fontsettings/fontsettings.js"></script>
<script src="../gitbook/gitbook-plugin-mermaid-gb3/mermaid/mermaid.min.js"></script>
</body>
</html>