smart-contract-watch

A tool that monitors smart contracts activity and interactions. It can be considered as a local blockchain explorer that runs locally in your server or machine. This processes is done by scanning transactions in the blockchain using diffrent RPC calls.

Currently the smart-contract-watch can run in two modes:

Default mode: the tool scans the blockchain block by block, transaction by transaction and log by log for any activity related to the monitored smart contracts. This is a slow processes and heavy on the node due to the high number of eth_getTransactionByHash and eth_getTransactionReceipt RPC requests. However, this approach gives the opportunity to add more features in the future like instrumenting the EVM or debugging transactions.
Fast mode: the tool gets all needed information from a whole block by only sending two RPC calls eth_getBlockByHash, get_logs. This proves to be more efficient and faster for direct scanning.

Additionally Smart Contract Watch currently has two output modes:

Terminal output: all marked transactions are outputted directly to the screen, in

[#address] function(param1,param2,...) log(event1,event2,......)
Graylog output: All transaction are to Graylog after formatting the results. communication to graylog is done through the Docker conatainer.

Input

The smart contract watch can take parameters in two diffrent modes

CLI
.watch.yml Config file

CLI

As a CLI tool you can run yarn run and then insert all needed parameters

Parameters:

-a [#address1,#address2,...] The only mandatory field if a config file is not provided, this represents an array of addresses to monitory.

-f Blocknumber Represents the from blocknumber if unspecified smart-contract-watch will start scanning from the first block number.

-t Blocknumber Represents the ending blocknumber where the smart-contract-watch will stop working when reached if left blank the smart-contract-watch will continue waiting for new blocking and scanning until manually exited.

-q Quick mode: Activates quick mode.

-s Save state mode: Saves the last scanned block when service restarts again. In order to use this you must include a store directory ex, -s /DIRECTORY or --save-state /DIRECTORY.

Config file

Smart Contract watch supports configration files. You must insert all your configration in a .watch.yml file. You can mix between both CLI and config file by filling only some of the needed fields, take into account that CLI overides config file.

How it works

Smart-contract-watch reports two different activities conducted by a smart contract using getTransaction, getTransactionReceipt

Direct transactions conducted from or to the monitored smart contracts. This is done by scanning the to, from fields in all transactions and reporting them back.
Log events generated by the monitored smart contract. This is helpful when scanning for internal transactions/activity not directly conducted by the monitored smart-contract.

How to use

Clone git repository using git clone
run yarn to install dependencies
run yarn start -f BLOCKNUMBER -t BLOCKNUMBER -a ARRAY_OF_ADDRESSES where
- -f represents the starting blocknumber
- -t represents the ending blocknumber
- -a represents an array of addresses

example: yarn start -f 4240705 -a 0x2c974b2d0ba1716e644c1fc59982a89ddd2ff724

Tests

yarn test

pgorsira / smart-contract-watch