Broadcasting

steem.broadcast.* methods sign a transaction with your private key and send it to the network. They cause permanent changes on the blockchain. For the full list of operations and their signatures, see the Broadcast reference.

Callbacks or Promises

Every broadcast method works both ways. Omit the callback to get a Promise.

const wif = steem.auth.toWif(username, password, 'posting');

// Promise (recommended)
steem.broadcast.vote(wif, voter, author, permlink, weight)
  .then(result => console.log(result))
  .catch(err => console.error(err));

// async / await
const result = await steem.broadcast.vote(wif, voter, author, permlink, weight);

// Callback (legacy)
steem.broadcast.vote(wif, voter, author, permlink, weight, (err, result) => {
  console.log(err, result);
});

An Async-suffixed variant (e.g. voteAsync) also exists for backwards compatibility, but the plain method already returns a Promise when you skip the callback.

Keys and roles

The first argument to every broadcast method is the signing key (wif). Each operation requires a particular key role — the Broadcast reference lists the accepted roles per operation. Most social actions (vote, comment) accept posting; moving funds requires active; account recovery and a few others require owner.

Derive a WIF from a username + master password with steem.auth.toWif, or use a stored private key directly. See the Auth guide.

How a transaction is built

steem.broadcast.send (which the per-operation methods call for you) does the following:

1. Fetches getDynamicGlobalProperties to set ref_block_num, ref_block_prefix, and a 10-minute expiration.
2. Signs the transaction with your key(s) via steem.auth.signTransaction.
3. Calls broadcast_transaction_synchronous and resolves with the node’s result merged with the signed transaction.

Multisignature

Call send directly with an array of keys to sign with more than one:

steem.broadcast.send(
  {
    extensions: [],
    operations: [
      ['vote', { voter: 'guest123', author: 'fabien', permlink: 'test', weight: 1000 }],
    ],
  },
  [privPostingWif1, privPostingWif2],
  (err, result) => console.log(err, result)
);

send also accepts a keys object keyed by role, e.g. { posting: wif }.

Account auth helpers

Four convenience methods read an account, modify one of its authorities, and broadcast the accountUpdate for you — handy for granting posting access to another account or key:

steem.broadcast.addAccountAuth(
  { signingKey, username: 'alice', authorizedUsername: 'someapp', role: 'posting' },
  (err, result) => console.log(err, result)
);

The full set — addAccountAuth, removeAccountAuth, addKeyAuth, removeKeyAuth — is documented in the Broadcast reference.