Query the Bitcoin memory pool in Python

The Bitcoin memory pool, also known as the “transaction pool” or “mempool,” is a holding area for unconfirmed transactions waiting to be added to a block. These transactions are broadcast to the network by users and await confirmation by miners. Querying the memory pool can provide valuable information about the current state of the network and the types of transactions being broadcast. In this article, we will explore how to query the Bitcoin memory pool using Python, the benefits of doing so and provide code samples to test.

Querying the memory pool can provide insights into the current state of the network. The number of unconfirmed transactions, the fees generated, and the types of transactions are indications of network useage. This information can be useful for developers, miners, and users to make informed decisions about the network. Additionally, this method can be used to monitor for transactions containing a specific address or fee amount.

Query the Bitcoin memory pool

To query the Bitcoin memory pool using Python, we can use the python-bitcoinrpc library, which allows for communication with a Bitcoin Core instance using the JSON-RPC protocol. This library can be installed using pip by running the command pip install python-bitcoinrpc.

pip install python-bitcoinrpc

Here is an example of how to query the memory pool using the python-bitcoinrpc library and determine the number of transactions in the memory pool:

from bitcoinrpc.authproxy import AuthServiceProxy

# Connect to local Bitcoin Core instance
rpc_user = "yourusername"
rpc_password = "yourpassword"
rpc_connection = AuthServiceProxy("http://%s:%s@127.0.0.1:8332" % (rpc_user, rpc_password))

# Get list of unconfirmed transactions
unconfirmed_txs = rpc_connection.getrawmempool()

# Print the number of unconfirmed transactions
print("Number of unconfirmed transactions:", len(unconfirmed_txs))

This example connects to a local Bitcoin Core instance using the JSON-RPC protocol, retrieves the list of unconfirmed transactions from the memory pool, and prints the number of unconfirmed transactions.

We can also use the getrawtransaction function to get more information about a specific transaction such as input and output, fee amount and other details. For example, we can print the full transaction for transactions over 100 bitcoin:

# Get list of unconfirmed transactions
unconfirmed_txs = rpc_connection.getrawmempool()

# Iterate through unconfirmed transactions
for txid in unconfirmed_txs:
    # Get raw transaction data
    raw_tx = rpc_connection.getrawtransaction(txid)

    # Decode transaction
    decoded_tx = rpc_connection.decoderawtransaction(raw_tx)

    # Print transaction details for transactions over 100 bitcoin
    if decoded_tx["value"] > 100:
        print(decoded_tx)

Different transactions in the memory pool

It’s also important to note that there are different types of transactions that can be found in the memory pool. The most common types include standard transactions, and coinbase transactions (rewards for adding a block to the blockchain). Additionally, there are also other types of transactions such as Bitcoin’s script-based transactions and SegWit transactions.

Different functions in bitcoinrpc

The python-bitcoinrpc library provides a wide range of functions for interacting with a Bitcoin Core instance using the JSON-RPC protocol. Some of the main functions that the library provides include:

  • getblockcount(): Returns the current number of blocks in the blockchain.
  • getblockhash(height): Returns the block hash for a given block height.
  • getblock(blockhash): Returns information about a specific block given its block hash.
  • getrawtransaction(txid): Returns the raw transaction data for a given transaction ID (txid).
  • decoderawtransaction(hex): Decodes a raw transaction in hex format and returns information about the transaction.
  • sendrawtransaction(hex): Broadcasts a raw transaction in hex format to the network.
  • getrawmempool(): Returns a list of unconfirmed transactions in the memory pool.
  • getbalance(): Returns the current balance of the wallet.
  • listaccounts(): Returns a list of all accounts and their balances in the wallet.
  • getnewaddress(): Returns a new address for the wallet.
  • listunspent(): Returns a list of unspent transaction outputs (UTXOs) for the wallet.
  • createrawtransaction(inputs, outputs): Creates a raw transaction with a given set of inputs and outputs.
  • signrawtransaction(hex, prevtxs, privkeys): Signs a raw transaction in hex format with a set of private keys.

These are some of the main functions provided by the python-bitcoinrpc library, but the library has many other functions available for interacting with the Bitcoin network and managing a Bitcoin wallet. It also allows you to send and receive bitcoin, signing transactions, etc.

Next Review – Use Python to get the balance of a Bitcoin wallet