Read Block Data in Blockchain

Q

How to Read Block Data from a Blockchain?

✍: FYIcenter.com

A

The block data from a blockchain uses a binary format. You need to use the "configtxgen -inspectBlock" command parse it to JSON format.

1. Get the newest block from the blockchain:

$ docker exec -it cli bash
root@262918fdcbc0:/opt/gopath/src/github.com/hyperledger/fabric/peer# cd
root@262918fdcbc0:~# peer channel fetch newest ./newest.block -c mychannel
root@262918fdcbc0:~# configtxgen -inspectBlock newest.block > newest.json

root@262918fdcbc0:~# more newest.json
{
  "data": {
    "data": [
      {
        "payload": {
          "data": {
            "actions": [
              {
                "header": {
                  "creator": {
"id_bytes": "LS0tLS1CRUdJTiBDRVJ...

Now you need to read the Hyperledger Fabric reference guide to figure out how transactions are stored in the block.

⇒ blockfile_000000 - Blockfiles of Blockchain

⇐ Verify Blockchain on the Channel

⇑ WYFA (Writing Your First Application)

⇑⇑ Hyperledger Tutorials

2020-02-20, 1916🔥, 0💬

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