Getting Started Overview Bandchain.js is a library written in TypeScript used for interacting with BandChain. The library provides classes and methods for convenient to send transactions, query data, OBI encoding, and wallet management.
The library is implemented based on gRPC-web protocol which sends HTTP/1.5 or HTTP/2 requests to a gRPC proxy server, before serving them as HTTP/2 to gRPC server.
The library support both Node.js and browsers.
System Requirements Browser Support The default build targets browsers that support both native ESM via script tags and native ESM dynamic import .
Installation NPM
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npm install --save @bandprotocol/bandchain.js
Yarn
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yarn add @bandprotocol/bandchain.js
Basic Usages Make an oracle request This section describes methods to send a transaction of oracle request to BandChain
Step 1: Import Client from @bandprotocol/bandchain.js and creates a new instance of grpcUrl as a parameter and you can get <GRPC_WEB> endpoint from here . Then initialize the client instance. Every method in client module can now be used.
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import { Client } from '@bandprotocol/bandchain.js'
const grpcUrl = '<GRPC_WEB>'
const client = new Client ( grpcUrl)
Step 2: Specify an account wallet for sending the transaction. This can be done by import PrivateKeyWallet module and input a 24-words mnemonic string as a seed. For this example, we will use following mnemonic for demonstration.
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subject economy equal whisper turn boil guard giraffe stick retreat wealth card only buddy joy leave genuine resemble submit ghost top polar adjust avoid
Here is the example on how to get a private key as an account.
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import { Wallet } from '@bandprotocol/bandchain.js'
const { PrivateKey } = Wallet
const privkey = PrivateKey. fromMnemonic (
'subject economy equal whisper turn boil guard giraffe stick retreat wealth card only buddy joy leave genuine resemble submit ghost top polar adjust avoid'
)
Then, we will use the private key to generate public key and a BAND address, as shown below
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const pubkey = privkey. toPubkey ( )
const sender = pubkey. toAddress ( ) . toAccBech32 ( )
Step 3: As we have both an Client instance and an account wallet, we can now construct a transaction by importing TransactionMsgRequestData
As the transaction object requires following attributes,
a list of messages account number sequence number chain ID fee with following optional fields
memo (default is empty string) We will firstly construct a MsgRequestData
Within MsgRequestData
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import { Obi, Message, Coin } from '@bandprotocol/bandchain.js'
const obi = new Obi ( '{symbols:[string],multiplier:u64}/{rates:[u64]}' )
const calldata = obi. encodeInput ( { symbols: [ 'ETH' ] , multiplier: 100 } )
const oracleScriptId = 37
const askCount = 4
const minCount = 3
const clientId = 'from_bandchain.js'
let feeLimit = new Coin ( )
feeLimit. setDenom ( 'uband' )
feeLimit. setAmount ( '100000' )
const prepareGas = 100000
const executeGas = 200000
const requestMessage = new Message. MsgRequestData (
oracleScriptId,
calldata,
askCount,
minCount,
clientId,
sender,
[ feeLimit] ,
prepareGas,
executeGas
)
After constructed MsgRequestData
Account and Sequence number are automatically gathered from Transaction's withSender Chain ID can be gathered from Client's getChainId
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import { Coin, Fee, Transaction } from '@bandprotocol/bandchain.js'
let feeCoin = new Coin ( )
feeCoin. setDenom ( 'uband' )
feeCoin. setAmount ( '50000' )
const fee = new Fee ( )
fee. setAmountList ( [ feeCoin] )
fee. setGasLimit ( 1000000 )
const chainId = await client. getChainId ( )
const txn = new Transaction ( )
txn. withMessages ( requestMessage)
await txn. withSender ( client, sender)
txn. withChainId ( chainId)
txn. withFee ( fee)
txn. withMemo ( '' )
Step 4: Sign and send the transaction
Now, we had an instance of constructed transaction. In order to sign the transaction, getSignDocTransactionPrivateKeysigngetTxData
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const signDoc = txn. getSignDoc ( pubkey)
const signature = privateKey. sign ( signDoc)
Step 5: Send the signed transaction to Bandchain be using following method of choices
For our example, we will use sendTxBlockMode
The final code should now look like the code below.
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import { Client, Wallet, Obi, Message, Coin, Transaction, Fee } from '@bandprotocol/bandchain.js'
const grpcUrl = '<GRPC_WEB>'
const client = new Client ( grpcUrl)
async function makeRequest ( ) {
const { PrivateKey } = Wallet
const mnemonic = 'test'
const privateKey = PrivateKey. fromMnemonic ( mnemonic)
const pubkey = privateKey. toPubkey ( )
const sender = pubkey. toAddress ( ) . toAccBech32 ( )
const obi = new Obi ( '{symbols:[string],multiplier:u64}/{rates:[u64]}' )
const calldata = obi. encodeInput ( { symbols: [ 'ETH' ] , multiplier: 100 } )
const oracleScriptId = 37
const askCount = 4
const minCount = 3
const clientId = 'from_bandchain.js'
let feeLimit = new Coin ( )
feeLimit. setDenom ( 'uband' )
feeLimit. setAmount ( '100000' )
const prepareGas = 100000
const executeGas = 200000
const requestMessage = new Message. MsgRequestData (
oracleScriptId,
calldata,
askCount,
minCount,
clientId,
sender,
[ feeLimit] ,
prepareGas,
executeGas
)
let feeCoin = new Coin ( )
feeCoin. setDenom ( 'uband' )
feeCoin. setAmount ( '50000' )
const fee = new Fee ( )
fee. setAmountList ( [ feeCoin] )
fee. setGasLimit ( 1000000 )
const chainId = await client. getChainId ( )
const txn = new Transaction ( )
txn. withMessages ( requestMessage)
await txn. withSender ( client, sender)
txn. withChainId ( chainId)
txn. withFee ( fee)
txn. withMemo ( '' )
const signDoc = txn. getSignDoc ( pubkey)
const signature = privateKey. sign ( signDoc)
const txRawBytes = txn. getTxData ( signature, pubkey)
const sendTx = await client. sendTxBlockMode ( txRawBytes)
console. log ( sendTx)
}
; ( async ( ) => {
await makeRequest ( )
} ) ( )
After, we run the script above, the result should look like this. The following log contains logs, which have events related to sent request.
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{
"height" : 438884 ,
"txhash" : "313DBAD237E3E672B432D7F9A422EF953EA42E1029F3562C9EE2AEFB70E7D5A3" ,
"codespace" : "" ,
"code" : 0 ,
"data" : "0A090A0772657175657374" ,
"rawLog" : "[{\"events\":[{\"type\":\"message\",\"attributes\":[{\"key\":\"action\",\"value\":\"request\"}]},{\"type\":\"raw_request\",\"attributes\":[{\"key\":\"data_source_id\",\"value\":\"61\"},{\"key\":\"data_source_hash\",\"value\":\"07be7bd61667327aae10b7a13..." ,
"logsList" : [ {
"msgIndex" : 0 ,
"log" : "" ,
"eventsList" : [
{ "type" : "message" , "attributesList" : [ { "key" : "action" , "value" : "request" } ] } ,
{ "type" : "raw_request" , "attributesList" : [ { "key" : "data_source_id" , "value" : "61" } ,
{ "key" : "data_source_hash" , "value" : "07be7bd61667327aae10b7a13a542c7dfba31b8f4c52b0b60bf9c7b11b1a72ef" } ,
{ "key" : "external_id" , "value" : "6" } ,
{ "key" : "calldata" , "value" : "BTC ETH" } ,
{ "key" : "fee" , "value" : "" } ,
{ "key" : "data_source_id" , "value" : "57" } ,
{ "key" : "data_source_hash" , "value" : "61b369daa5c0918020a52165f6c7662d5b9c1eee915025cb3d2b9947a26e48c7" } ,
{ "key" : "external_id" , "value" : "0" } ,
{ "key" : "calldata" , "value" : "BTC ETH" } ,
{ "key" : "fee" , "value" : "" } ,
{ "key" : "data_source_id" , "value" : "62" } ,
{ "key" : "data_source_hash" , "value" : "107048da9dbf7960c79fb20e0585e080bb9be07d42a1ce09c5479bbada8d0289" } ,
{ "key" : "external_id" , "value" : "3" } ,
{ "key" : "calldata" , "value" : "BTC ETH" } ,
{ "key" : "fee" , "value" : "" } ,
{ "key" : "data_source_id" , "value" : "60" } ,
...,
{ "key" : "calldata" , "value" : "BTC ETH" } ,
{ "key" : "fee" , "value" : "" } ] } ,
{ "type" : "request" , "attributesList" : [ { "key" : "id" , "value" : "74473" } ,
{ "key" : "client_id" , "value" : "from_bandchain.js" } ,
{ "key" : "oracle_script_id" , "value" : "37" } ,
{ "key" : "calldata" , "value" : "0000000200000003425443000000034554480000000000000064" } ,
{ "key" : "ask_count" , "value" : "4" } ,
{ "key" : "min_count" , "value" : "3" } ,
{ "key" : "gas_used" , "value" : "111048" } ,
{ "key" : "total_fees" , "value" : "" } ,
{ "key" : "validator" , "value" : "bandvaloper1p46uhvdk8vr829v747v85hst3mur2dzlhfemmz" } ,
{ "key" : "validator" , "value" : "bandvaloper1v0u0tsptnkcdrju4qlj0hswqhnqcn47d20prfy" } ,
{ "key" : "validator" , "value" : "bandvaloper17n5rmujk78nkgss7tjecg4nfzn6geg4cqtyg3u" } ,
{ "key" : "validator" , "value" : "bandvaloper19eu9g3gka6rxlevkjlvjq7s6c498tejnwxjwxx" }
] } ] } ] ,
"info" : "" ,
"gasWanted" : 1500000 ,
"gasUsed" : 660549 ,
"timestamp" : ""
}
Send BAND token Sending BAND token has code pattern similar to the previous section, except that different type of message is used.
The message used for this section is MsgSend
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const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
const sendAmount = new Coin ( )
sendAmount. setDenom ( 'uband' )
sendAmount. setAmount ( '10' )
const msg = new MsgSend ( sender, receiver, [ sendAmount] )
Therefore, final result is as shown follow
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import { Client, Wallet, Transaction, Message, Coin, Fee } from '@bandprotocol/bandchain.js'
const { PrivateKey } = Wallet
const client = new Client ( '<GRPC_WEB>' )
const privkey = PrivateKey. fromMnemonic (
'subject economy equal whisper turn boil guard giraffe stick retreat wealth card only buddy joy leave genuine resemble submit ghost top polar adjust avoid'
)
const pubkey = privkey. toPubkey ( )
const sender = pubkey. toAddress ( ) . toAccBech32 ( )
const sendCoin = async ( ) => {
const { MsgSend } = Message
const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
const sendAmount = new Coin ( )
sendAmount. setDenom ( 'uband' )
sendAmount. setAmount ( '10' )
const msg = new MsgSend ( sender, receiver, [ sendAmount] )
const account = await client. getAccount ( sender)
const chainId = 'band-laozi-testnet6'
let feeCoin = new Coin ( )
feeCoin. setDenom ( 'uband' )
feeCoin. setAmount ( '1000' )
const fee = new Fee ( )
fee. setAmountList ( [ feeCoin] )
fee. setGasLimit ( 1000000 )
const tx = new Transaction ( )
. withMessages ( msg)
. withAccountNum ( account. accountNumber)
. withSequence ( account. sequence)
. withChainId ( chainId)
. withFee ( fee)
const txSignData = tx. getSignDoc ( pubkey)
const signature = privkey. sign ( txSignData)
const signedTx = tx. getTxData ( signature, pubkey)
const response = await client. sendTxBlockMode ( signedTx)
console. log ( response)
}
; ( async ( ) => {
await sendCoin ( )
} ) ( )
The response should be similar to as shown below
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{
"height" : 443301 ,
"txhash" : "026760F78665C03DD4A8786304E01848A4747F0B62F7DB4B31F93C792B2D3D52" ,
"codespace" : "" ,
"code" : 0 ,
"data" : "0A060A0473656E64" ,
"rawLog" : "[{\"events\":[{\"type\":\"message\",\"attributes\":[{\"key\":\"action\",\"value\":\"send\"},{\"key\":\"sender\",\"value\":\"band168ukdplr7nrljaleef8ehpyvfhe4n78hz0shsy\"},{\"key\":\"module\",\"value\":\"bank\"}]},{\"type\":\"transfer\",\"attributes\":[{\"key\":\"recipient\",\"value\":\"band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f\"},{\"key\":\"sender\",\"value\":\"band168ukdplr7nrljaleef8ehpyvfhe4n78hz0shsy\"},{\"key\":\"amount\",\"value\":\"10uband\"}]}]}]" ,
"logsList" : [
{
"msgIndex" : 0 ,
"log" : "" ,
"eventsList" : [
{
"type" : "message" ,
"attributesList" : [
{ "key" : "action" , "value" : "send" } ,
{
"key" : "sender" ,
"value" : "band168ukdplr7nrljaleef8ehpyvfhe4n78hz0shsy"
} ,
{ "key" : "module" , "value" : "bank" }
]
} ,
{
"type" : "transfer" ,
"attributesList" : [
{
"key" : "recipient" ,
"value" : "band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f"
} ,
{
"key" : "sender" ,
"value" : "band168ukdplr7nrljaleef8ehpyvfhe4n78hz0shsy"
} ,
{ "key" : "amount" , "value" : "10uband" }
]
}
]
}
] ,
"info" : "" ,
"gasWanted" : 1500000 ,
"gasUsed" : 49013 ,
"timestamp" : ""
}
Get reference data This section shows an example on how to query data from BandChain. This example query standard price references based on given symbol pairs, min count, and ask count.
Step 1: Import bandchain.js and put grpc_url_web as a parameter and you can get <GRPC_WEB> endpoint from here . Then initialize the client instance. Every method in client module can now be used.
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import { Client } from '@bandprotocol/bandchain.js'
const grpcUrl = '<GRPC_WEB>'
const client = new Client ( grpcUrl)
Step 2: After we import the ClientClientgetReferenceData
There are 3 parameters
minCount: Integer of min count askCount: Integer of ask count pairs: The list of cryprocurrency pairs The final code should look like the code below.
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import { Client } from "@bandprotocol/bandchain.js"
const grpcUrl = "<GRPC_WEB>"
const client = new Client ( grpcUrl)
const minCount = 3
const askCount = 4
const pairs = [ "BTC/USD" , "ETH/USD" ( async ( ) => {
console. log ( JSON . stringify ( await client. getReferenceData ( pairs, minCount, askCount) ) )
} ) ( )
And the result should look like this.
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[
{
"pair" : "BTC/USD" ,
"rate" : 34078.0954 ,
"updatedAt" : {
"base" : 1625579610 ,
"quote" : 1625579627
} ,
"requestId" : {
"base" : 79538 ,
"quote" : 0
}
} ,
{
"pair" : "ETH/BTC" ,
"rate" : 0.06759872648278929 ,
"updatedAt" : {
"base" : 1625579610 ,
"quote" : 1625579610
} ,
"requestId" : {
"base" : 79538 ,
"quote" : 79538
}
}
]
Send BAND token via IBC Transfer With BandChain built based on the Cosmos-SDK, we also allow interaction with our data oracle through Cosmos Inter-Blockchain-Communication protocol, IBC , which connects other compatible blockchains to request data from BandChain.
To send BAND tokens through IBC Protocol, we will use MsgTransferhere .
Step 1: First, you need to create a MsgTransfer instance from the Message module. The following code shows you how to create the instance.​
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import { Message } from '@bandprotocol/bandchain.js'
const { MsgTransfer } = Message
Step 2: Now we can construct the MsgTransfer method, this method requires 5 fields to interact with:
Field Type Description sourcePort string The port on which the packet will be sent sourceChannel string The channel by which the packet will be sent sender string The sender address receiver string The recipient address on the destination chain token Coin The tokens to be transferred timeoutTimestamp number Timeout timestamp (in nanoseconds) relative to the current block timestamp.
Your code should look like this.
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const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
const sourcePort = 'transfer'
const sourceChannel = 'channel-25'
const sendAmount = new Coin ( )
sendAmount. setDenom ( 'uband' )
sendAmount. setAmount ( '10' )
const timeoutTimestamp = moment ( ) . unix ( ) + 600 * 1e9
const msg = new MsgTransfer (
sourcePort,
sourceChannel,
sendAmount,
sender,
receiver,
timeout_timestamp
)
To find the right channel IDs for each chain to perform Interchain Transfers, go to the BandChain's GraphQL Console with the following query.
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query MyQuery {
connections(
where: { channels: { port: { _eq: "transfer" } } }
order_by: { counterparty_chain_id: asc }
) {
channels(where: { port: { _eq: "transfer" } }) {
channel
port
}
counterparty_chain_id
}
}
This query will list all the available IBC Relayers. like so:
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{
"data" : {
"connections" : [
{
"channels" : [
{
"channel" : "channel-91" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "anca-1"
} ,
{
"channels" : [
{
"channel" : "channel-12" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "comdex-dev1"
} ,
{
"channels" : [
{
"channel" : "channel-11" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "comdex-dev1"
} ,
{
"channels" : [
{
"channel" : "channel-14" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "comdex-dev1"
} ,
{
"channels" : [
{
"channel" : "channel-13" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "comdexdevnet-4"
} ,
{
"channels" : [
{
"channel" : "channel-25" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "consumer"
} ,
{
"channels" : [
{
"channel" : "channel-114" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "ibcoracle"
} ,
{
"channels" : [
{
"channel" : "channel-116" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "ibcoracle"
} ,
{
"channels" : [
{
"channel" : "channel-117" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "ibcoracle"
} ,
{
"channels" : [
{
"channel" : "channel-90" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "injective-1"
} ,
{
"channels" : [
{
"channel" : "channel-0" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "kichain-t-4"
} ,
{
"channels" : [
{
"channel" : "channel-28" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "sifchain-testnet-1"
} ,
{
"channels" : [
{
"channel" : "channel-252" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-256" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-257" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-30" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-38" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-46" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-69" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-93" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-96" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-139" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-162" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-164" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-169" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
} ,
{
"channels" : [
{
"channel" : "channel-208" ,
"port" : "transfer"
}
] ,
"counterparty_chain_id" : "test-1"
}
]
}
}
Your final code should look something like this:
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import { Client, Wallet, Transaction, Message, Coin, Fee } from '@bandprotocol/bandchain.js'
const { PrivateKey } = Wallet
const client = new Client ( '<GRPC_WEB>' )
const privkey = PrivateKey. fromMnemonic (
'subject economy equal whisper turn boil guard giraffe stick retreat wealth card only buddy joy leave genuine resemble submit ghost top polar adjust avoid'
)
const pubkey = privkey. toPubkey ( )
const sender = pubkey. toAddress ( ) . toAccBech32 ( )
const sendCoinIbc = async ( ) => {
const { MsgTransfer } = Message
const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
const sourcePort = 'transfer'
const sourceChannel = 'channel-25'
const sendAmount = new Coin ( )
sendAmount. setDenom ( 'uband' )
sendAmount. setAmount ( '10' )
const timeoutTimestamp = moment ( ) . unix ( ) + 600 * 1e9
const msg = new MsgTransfer (
sourcePort,
sourceChannel,
sendAmount,
sender,
receiver,
timeout_timestamp
)
const account = await client. getAccount ( sender)
const chainId = 'band-laozi-testnet6'
let feeCoin = new Coin ( )
feeCoin. setDenom ( 'uband' )
feeCoin. setAmount ( '1000' )
const fee = new Fee ( )
fee. setAmountList ( [ feeCoin] )
fee. setGasLimit ( 1000000 )
const tx = new Transaction ( )
. withMessages ( msg)
. withAccountNum ( account. accountNumber)
. withSequence ( account. sequence)
. withChainId ( chainId)
. withFee ( fee)
const txSignData = tx. getSignDoc ( pubkey)
const signature = privkey. sign ( txSignData)
const signedTx = tx. getTxData ( signature, pubkey)
const response = await client. sendTxBlockMode ( signedTx)
console. log ( response)
}
; ( async ( ) => {
await sendCoinIbc ( )
} ) ( )
Connect to your app with Ledger This tutorial guides you through how to set up and use the Bandchain.js library with your Ledger device to access your Ledger Cosmos (BAND) account(s).
Supported Browsers
Chrome Edge (89.0 and later) Opera (76.0 and later) we strongly recommend using Chrome.
To connect your app you will need to install:
Ledger Live The Cosmos Nano App At least one account for Band Accessing your Ledger
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import { Wallet } from '@bandprotocol/bandchain.js'
const { Ledger } = Wallet
const connectLedger = async ( ) => {
const ledger = await Ledger. connectLedgerWeb ( )
console. log ( ledger)
}
; ( async ( ) => {
await connectLedger ( )
} ) ( )
Sending Band Token using Ledger To send BAND token using Ledger device, the final code should look something like this:
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import { Wallet, Client, Transaction, Message, Coin, Fee } from '@bandprotocol/bandchain.js'
const sendCoinWithLedger = async ( ) => {
const ledger = await Ledger. connectLedgerWeb ( )
const { MsgSend } = Message
const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
const sendAmount = new Coin ( )
sendAmount. setDenom ( 'uband' )
sendAmount. setAmount ( '10' )
const msg = new MsgSend ( sender, receiver, [ sendAmount] )
const account = await client. getAccount ( sender)
const chainId = 'band-laozi-testnet6'
let feeCoin = new Coin ( )
feeCoin. setDenom ( 'uband' )
feeCoin. setAmount ( '1000' )
const fee = new Fee ( )
fee. setAmountList ( [ feeCoin] )
fee. setGasLimit ( 1000000 )
const tx = new Transaction ( )
. withMessages ( msg)
. withChainId ( chainId)
. withFee ( fee)
. withMemo ( '' )
await tx. withSender ( client, bech32_address)
const signature = await ledger. sign ( tx)
const signedTx = tx. getTxData ( signature, pubKey, 127 )
const response = await client. sendTxBlockMode ( signedTx)
console. log ( response)
}
; ( async ( ) => {
await sendCoinWithLedger ( )
} ) ( )
Getting Testnet BAND from Faucet
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async function getFaucet ( ) {
const body = {
address: 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f' ,
amount: '10' ,
}
let options = {
method: 'POST' ,
headers: {
'Content-Type' : 'application/json;charset=utf-8' ,
} ,
body: JSON . stringify ( body) ,
}
let response = await fetch ( ` ${ BAND_FAUCET_ENDPOINT } ` , options)
console. log ( response)
}
getFaucet ( )
And these are examples of Bandchain.js usages, for more information, feel free to dive into specifications in each module.
