This parser communicates with a Bitcoin node to extract and decode blocks & transactions.

Chainwalkers Framework Docs: docs.flipsidecrypto.com

Create a .secrets.json at the top level directory with a node url. Chainwalkers will use this to communicate with a Bitcoin node's RPC interface.

{
  "NODE_URL": "{protocol}://{username}:{password}@{host}:{port}"
}

A docker image of the Bitcoin chainwalker can be built by running:

bash builder_docker_image.sh

This will create an image with the tag chainwalkers_bitcoin:latest.

This parser has two entry points, each of which writes a json response to stdout.

1. get_height.sh: returns the current height
2. parse_blocks.sh [int, int, ...]: returns an array of decoded blocks and each blocks transactions

To get the latest height of the blockchain run:

> docker run chainwalkers_bitcoin:latest bash get_height.sh
{
    "height": 574158
}

To parse a list of blocks run:

> docker run chainwalkers_bitcoin:latest bash parse_blocks.sh 200000 200001 200002
[
    {
        "height": 200000,
        "hash": "000000000000034a7dedef4a161fa058a2d67a173a90155f3a2fe6fc132e0ebf",
        ...,
        "transactions": [
            {
                "id": "",
                "hash": "",
                "vin": [
                    {
                        "prev_output": {...},
                        ...
                    },
                    ...
                ],
                "vout": [...],
                ...
            }
        ],
        ...
    },
    ...
]

Note that each "vin" object include a reference to it's previous output vector. This is required for all UTXO style chains integrating with Chainwalkers (we use bulk RPC calls to make the inclusion of this data as efficient as possible).