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OsmoJS

OsmosJS makes it easy to compose and broadcast Osmosis and Cosmos messages, with all of the proto and amino encoding handled for you.

usage​

npm install osmojs

Composing Messages​

Import the osmosis object from osmojs. In this case, we're show the messages available from the osmosis.gamm.v1beta1 module:

import { osmosis } from 'osmojs';

const {
    joinPool,
    exitPool,
    exitSwapExternAmountOut,
    exitSwapShareAmountIn,
    joinSwapExternAmountIn,
    joinSwapShareAmountOut,
    swapExactAmountIn,
    swapExactAmountOut
} = osmosis.gamm.v1beta1.MessageComposer.withTypeUrl;

To see a complete list of messages, see the section below.

Now you can construct messages. If you use vscode or another typescript-enabled IDE, you should also be able to use ctrl+space to see auto-completion of the fields required for the message.

import { coin } from '@cosmjs/amino';

const msg = swapExactAmountIn({
  sender,
  routes,
  tokenIn: coin(amount, denom),
  tokenOutMinAmount
});

(If you want to see an example of calculating routes and tokenOutMinAmount cosmology uses osmojs and has an example here.)

Calculating Fees​

Make sure to create a fee object in addition to your message.

For most messages, you can use the predefined fee objects.

import { FEES } from 'osmojs';

const fee = FEES.osmosis.swapExactAmountIn();

You can also specify low, medium, or high for fees:

const fee = FEES.osmosis.swapExactAmountIn('low');
const fee = FEES.osmosis.swapExactAmountIn('medium');
const fee = FEES.osmosis.swapExactAmountIn('high');

Or you can construct manually if you wish:

import { coins } from '@cosmjs/amino';

const fee = {
    amount: coins(0, 'uosmo'),
    gas: '250000'
}

if you are broadcasting multiple messages in a batch, you should simulate your tx and estimate the fee

import { Dec, IntPretty } from '@keplr-wallet/unit';

const gasEstimated = await stargateClient.simulate(address, msgs, memo);
const fee = {
  amount: coins(0, 'uosmo'),
  gas: new IntPretty(new Dec(gasEstimated).mul(new Dec(1.3)))
    .maxDecimals(0)
    .locale(false)
    .toString()
};

Doing a swap​

  const signingClient = await getSigningOsmosisClient({
      rpcEndpoint: getRpcEndpoint(),
      signer: aminoSigner
    });

    const ibcDenom = pool.poolAssets.find((asset) => {
      if (asset.token.denom.startsWith('ibc/')) {
        return asset;
      }
    }).token.denom;

    const balanceBefore = await signingClient.getBalance(address, ibcDenom);

    const msg =
      osmosis.gamm.v1beta1.MessageComposer.withTypeUrl.swapExactAmountIn({
        sender: address,
        routes: [
          {
            poolId,
            tokenOutDenom: ibcDenom
          }
        ],
        tokenIn: {
          amount: '200000',
          denom: denom
        },
        tokenOutMinAmount: '100000'
      });

    const fee = {
      amount: [
        {
          denom,
          amount: '100000'
        }
      ],
      gas: '550000'
    };

    const result = await signingClient.signAndBroadcast(
      address,
      [msg],
      fee,
      'swap tokens'
    );

Initializing the Stargate Client​

Use getSigningOsmosisClient to get your SigningStargateClient, with the Osmosis proto/amino messages full-loaded. No need to manually add amino types, just require and initialize the client:

import { getSigningOsmosisClient } from 'osmojs';

const client = await getSigningOsmosisClient({
  rpcEndpoint,
  signer // OfflineSigner
});

Creating Signers​

To broadcast messages, you'll want to use either keplr or an OfflineSigner from cosmjs using mnemonics.

Amino Signer​

Likely you'll want to use the Amino, so unless you need proto, you should use this one:

import { getOfflineSigner as getOfflineSignerAmino } from 'osmojs';

Proto Signer​

import { getOfflineSigner as getOfflineSignerProto } from 'osmojs';

WARNING: NOT RECOMMENDED TO USE PLAIN-TEXT MNEMONICS. Please take care of your security and use best practices such as AES encryption and/or methods from 12factor applications.

import { chains } from 'chain-registry';

const mnemonic =
  'unfold client turtle either pilot stock floor glow toward bullet car science';
  const chain = chains.find(({ chain_name }) => chain_name === 'osmosis');
  const signer = await getOfflineSigner({
    mnemonic,
    chain
  });

Broadcasting messages​

Now that you have your client, you can broadcast messages:

import { signAndBroadcast } from 'osmojs';

const res = await signAndBroadcast({
  client, // SigningStargateClient
  chainId: 'osmosis-1', // use 'osmo-test-6' for testnet
  address,
  msgs: [msg],
  fee,
  memo: ''
});

Osmosis Messages​

import { osmosis } from 'osmojs';

const {
    beginUnlocking,
    beginUnlockingAll,
    lockTokens
} = osmosis.lockup.MessageComposer.withTypeUrl;

const {
    lockAndSuperfluidDelegate,
    superfluidDelegate,
    superfluidUnbondLock,
    superfluidUndelegate
} = osmosis.superfluid.MessageComposer.withTypeUrl;

const {
    addToGauge,
    createGauge
} = osmosis.incentives.MessageComposer.withTypeUrl;

const {
    joinPool,
    exitPool,
    exitSwapExternAmountOut,
    exitSwapShareAmountIn,
    joinSwapExternAmountIn,
    joinSwapShareAmountOut,
    swapExactAmountIn,
    swapExactAmountOut
} = osmosis.gamm.v1beta1.MessageComposer.withTypeUrl;

IBC Messages​

import { ibc } from 'osmojs';

const {
    transfer
} = ibc.applications.transfer.v1.MessageComposer.withTypeUrl

Cosmos Messages​

import { cosmos } from 'osmojs';

const {
    fundCommunityPool,
    setWithdrawAddress,
    withdrawDelegatorReward,
    withdrawValidatorCommission
} = cosmos.distribution.v1beta1.MessageComposer.fromPartial;

const {
    multiSend,
    send
} = cosmos.bank.v1beta1.MessageComposer.fromPartial;

const {
    beginRedelegate,
    createValidator,
    delegate,
    editValidator,
    undelegate
} = cosmos.staking.v1beta1.MessageComposer.fromPartial;

const {
    deposit,
    submitProposal,
    vote,
    voteWeighted
} = cosmos.gov.v1beta1.MessageComposer.fromPartial;

CosmWasm Messages​

import { cosmwasm } from "osmojs";

const {
    clearAdmin,
    executeContract,
    instantiateContract,
    migrateContract,
    storeCode,
    updateAdmin
} = cosmwasm.wasm.v1.MessageComposer.withTypeUrl;

Further examples​

Examples in create-cosmos-app repo's examples directory gives you a great guideline on how osmojs can be used at its full extent.

You can also refer to the osmojs documentation for further documentations on osmojs usage.

Credits​

🛠 Built by Cosmology — if you like our tools, please consider delegating to our validator ⚛️

Code built with the help of these related projects:

  • @osmonauts/telescope a "babel for the Cosmos", Telescope is a TypeScript Transpiler for Cosmos Protobufs.

Disclaimer​

AS DESCRIBED IN THE OSMOJS LICENSES, THE SOFTWARE IS PROVIDED “AS IS”, AT YOUR OWN RISK, AND WITHOUT WARRANTIES OF ANY KIND.

No developer or entity involved in creating OsmoJS will be liable for any claims or damages whatsoever associated with your use, inability to use, or your interaction with other users of the OsmoJS code, including any direct, indirect, incidental, special, exemplary, punitive or consequential damages, or loss of profits, cryptocurrencies, tokens, or anything else of value.