Fralgo
June 21, 2022, 9:43am
1
I am trying to retrieve Algorand transactions using the v2/blocks/{round} endpoint, but the JSON response does not contain any transaction or block hashes. Is there any way to construct these using the data in the response without using the SDKs?
1 Like
Check this out: vote-coin-indexer/computeTransactionId.ts at master · scholtz/vote-coin-indexer · GitHub
//console.log('block.block', block.block);
if (block.block.txns) {
let countProcessedTxns = 0;
//console.log('block.block.txns', block.block.txns.length);
for (const stxn of block.block.txns) {
countProcessedTxns++;
try {
if (!stxn.txn.note) continue;
const note = Buffer.from(stxn.txn.note).toString('utf-8');
if (!note.startsWith('avote-')) continue;
const txId = computeTransactionId(block.block.gh, block.block.gen, stxn);
const pos = note.indexOf(':');
let messageType = note.substring(0, pos);
const posSlash = note.indexOf('/');
const posSlash2 = note.indexOf('/', posSlash + 1);
if (posSlash2 > 0) {
messageType = messageType.substring(0, posSlash2);
}
//console.log('posSlash2', posSlash2);
const dataStr = note.substring(pos + 2);
//console.log(dataStr)
1 Like
Another solution is to query the indexer rather than the algod endpoint.
1 Like
Fralgo
June 22, 2022, 11:44am
4
Unfortunately, the indexer only seems to give the previous block hash and not the current one so that doesn’t solve every issue.
I read too fast, I thought you meant transaction ID for some reason.
You can get the current block hash as shown there:
This is available in the certificate of the block that you can get by querying the block as msgpack (?format=msgpack).
In JS:
const algosdk = require("algosdk");
const base32 = require("hi-base32");
const c = new algosdk.Algodv2("", "https://testnet.algoexplorerapi.io", "");
(async () => {
const blk = await c.block(13819291).do();
const blk_hash = base32.encode(blk["cert"]["prop"]["dig"]);
console.log(blk_hash);
})();
Other SDKs work similarly, the client methods are: GetBlock for Jav…