toinetoine / Ethereum-Block-Grabber

Grabs all blocks on the ethereum blockchain from a specified geth instance

Ethereum Block Grabber

Creates a <block_number>.json file for each block from a locally running geth instance. This alllows you to perform analytics on the blockchain without having to simulatenously run a geth instance or rely on an external API.

Getting It Running

1. Install geth and sync it (speedup syncing by adding the --syncmode "fast" argument the first time you run geth).
2. Start geth with the HTTP-RPC server enabled: geth --rpc --rpccorsdomain "http://localhost:8000".
3. After 20-30 seconds of geth running, run the application (node app.js).

Config

The config file is optional. Without the config file it will create block files for all blocks recursively (from the latest block downloaded on your local geth instance through it's ancestors to block 0) and save them in the root directory of the project.

Running with config.json at the root of the project allows you to download specific blocks or intervals of blocks:

{
    "output": "./blockfiles",
    "gethPort": 8545,
    "blocks": [ 1, {"start": 2, "end": 4}, "0xf37c632d361e0a93f08ba29b1a2c708d9caa3ee19d1ee8d2a02612bffe49f0a9"],
    "quiet": true
}

This configuration will:

• download blocks: 1, [2-4] (both inclusive), and the block with hash 0xf37c632d...49f0a9 (which happens to be block number 5).
• save the information for each block in a file named <block number>.json in the directory ./block_files.
• assume geth's RPC port is 8545 (default), you can change the port it runs on by adding the --rpcport <port> argument when running geth.

Note: the blocks array in the config file takes an array of specific block numbers, block number ranges, and/or block hashes to download (or any combination/multiple of the 3).

Note: By default it will create a file for all blocks starting from the last block your geth instance has synced until it encounters a block that already has a file named <block's number>.json, in which case it will stop (so in an empty directory it will create a file for all blocks from the latest block you've synced back to the genesis block).

Note: the python scripts in the script directory are utilities to run on the blocks' JSON files.