add query ethereum blockchain tutorial

Author: x4nth055

Diff for: README.md

@@ -119,6 +119,7 @@ This is a repository of all the tutorials of [The Python Code](https://www.thepy
     - [Zipf's Word Frequency Plot with Python](https://www.thepythoncode.com/article/plot-zipfs-law-using-matplotlib-python). ([code](general/zipf-curve))
     - [How to Plot Weather Temperature in Python](https://www.thepythoncode.com/article/interactive-weather-plot-with-matplotlib-and-requests). ([code](general/interactive-weather-plot/))
     - [How to Generate SVG Country Maps in Python](https://www.thepythoncode.com/article/generate-svg-country-maps-python). ([code](general/generate-svg-country-map))
+    - [How to Query the Ethereum Blockchain with Python](https://www.thepythoncode.com/article/query-ethereum-blockchain-with-python). ([code](general/query-ethereum))
 
 
 

Diff for: general/query-ethereum/README.md

@@ -0,0 +1 @@
+# [How to Query the Ethereum Blockchain with Python](https://www.thepythoncode.com/article/query-ethereum-blockchain-with-python)

Diff for: general/query-ethereum/query_ethereum_blockchain.py

@@ -0,0 +1,116 @@
+from web3 import Web3
+
+# infura API key
+API_KEY = "put your API key here"
+# change endpoint to mainnet or ropsten or any other of your account
+url = f"https://<endpoint>.infura.io/v3/{API_KEY}"
+
+w3 = Web3(Web3.HTTPProvider(url))
+# see whether the connection is established
+res = w3.isConnected()
+print(res)
+
+
+# get latest block
+latest = w3.eth.get_block('latest')
+print(latest)
+# print the block number
+print(latest['number'])
+
+
+# query individual transactions
+transaction1 = w3.eth.get_transaction('0x0e3d45ec3e1d145842ce5bc56ad168e4a98508e0429da96c1ff89f11076da36d')
+print(transaction1)
+
+
+# use block number to query transactions
+transaction2 = w3.eth.get_transaction_by_block(15410924, 0)
+print(transaction2)
+
+
+# get number of transactions in a block
+transactionCount = w3.eth.get_transaction_count('0x486976656f6e2065752d68656176792d657163')
+print(transactionCount)
+
+
+# check if a block address is valid
+isValid = w3.isAddress('0xed44e77fb3408cd5ad415d7467af6f6783218fb74c3824de1258f6d266bcc7b7')
+print(isValid)
+
+
+# check if an address is a valid EIP-55 checksum address
+isChecksumAddressValid = Web3.isChecksumAddress('0x486976656f6e2065752d68656176792d657163')
+print(isChecksumAddressValid)
+
+
+# get balance of a block address
+balance = w3.eth.get_balance('0xd3CdA913deB6f67967B99D67aCDFa1712C293601')
+print(balance)
+
+
+# get proof of a block
+proof = w3.eth.get_proof('0x486976656f6e2065752d68656176792d657163', [0], 3391)
+print(proof)
+
+
+# get uncle of a block
+w3.eth.get_uncle_by_block(15410924, 0)
+
+
+nonce = w3.eth.getTransactionCount('0x610Ae88399fc1687FA7530Aac28eC2539c7d6d63', 'latest')
+# create a transaction
+transaction = {
+     'to': '0x31B98D14007bDEe637298086988A0bBd31184523', 
+     'from': '0x31B98D14007bDEe63EREEDFT34544646MOI22',
+     'value': 500,
+     'gas': 10000,
+     'maxFeePerGas': 1000000208,
+     'nonce': nonce,
+}
+# send the transaction
+w3.eth.send_transaction(transaction)
+
+
+# sign a transaction
+signed = w3.eth.sign_transaction(
+    dict(
+        nonce=nonce,
+        maxFeePerGas=34300000,
+        maxPriorityFeePerGas=25000000,
+        gas=100000,
+        to='0xerecfBYWlB99D67aCDFa17EREFEerrtr73601',
+        value=1,
+        data=b'',
+    )
+)
+
+address = '0x706f6f6c696e2e636f6d21688947c8f76c4e92'
+abi = '[{"inputs":[{"internalType":"address","name":"account","type":"address"},{"internalType":"address","name":"minter_",........' # abi of the contract
+# create a contract object
+contract = w3.eth.contract(address=address, abi=abi)
+
+
+# total supply of the token
+totalSupply = contract.functions.totalSupply().call()
+print(totalSupply)
+
+
+# read the data and update the state
+contract.functions.storedvalue().call()
+tx_hash = contract.functions.updateValue(100).transact()
+
+
+# retrieve token metadata
+print(contract.functions.name().call())
+print(contract.functions.decimals().call())
+print(contract.functions.symbol().call())
+# output:
+# SHIBACHU
+# 9
+# SHIBACHU
+
+
+# find the account balance
+address = '0x5eaaf114aad1313e7440d2ff805ced993e566df'
+balance = contract.functions.balanceOf(address).call()
+

Diff for: general/query-ethereum/requirements.txt

@@ -0,0 +1 @@
+web3