Ethereum Proxy on AWS Lambda

AWS Lambda project as ethereum proxy following JSON-RPC, written in Golang. In addition, this project try porting web3 to Golang. Furthermore it applied IPFS API here to overwhelm limited storage of blockchain.

Contents

• Features
• Prerequisite
• Build
• Test
• Usage
• Deploy (for AWS Lambda)
• Documentation
• Reference
• License

Features

1. JSON-RPC relay with Ethereum node
2. Proofs for sign and merkle tree such as Ecrecover, DeriveSha, VerifyProof and so on
3. Sign, SignTx with encrypted private key on DynamoDB/Local
4. IPFS interface
5. fromWei, toWei written in Golang

Prerequisite

0. Go

• Install at https://golang.org/doc/install

1. dep

• Install

brew install dep

2. Docker

• Install at https://docs.docker.com/install

3. xgo

• because of compilation for C code used in go-ethereum, we need improved cross-compiler

docker pull karalabe/xgo-latest
go get github.com/karalabe/xgo

Build

1. Move to root directory of this repo
2. Build on your preference

• In case of Lambda that is cross-compile, make or make lambda
• In case of Lambda with remote branch, make branch=master remote
• In case of local machine compile, make local

Test

1. Move each module directory such as json, rpc and so on
2. Run testunit

go test -v

Usage

1. $> proxy [KEY_JSON_PATH] -log_lev=debug -log_out=/log/proxy.log -log_fmt=json
2. $> proxy [KEY_JSON_PATH] [KEY_JSON_PASSPHRASE] -log_lev=debug -log_out=/log/proxy.log -log_fmt=json

• path and passphrase for key json are NECESSARY now for crypto module.
• log_lev, log_out, log_fmt, log_bot_token and log_bot_chatid are optional
• description:
  • log_lev: log level
  • log_out: log output location
  • log_fmt: log format, text or JSON
  • log_bot_token: telegram access token
  • log_bot_chatid: telegram chat ID
• default:
  • log_lev: info
  • log_out: stdout
  • log_fmt: text

Deploy (for AWS Lambda)

1. Set Lambda on AWS

• Function package: compressed binary file in $GOPATH/src/{repo}/bin
• Handler: eth-proxy (binary file name, it is optional)
• Runtime: Go 1.x
• (Optional) Include DynamoDB execution role to Lambda execution role

2. Set API Gateway as proxy on AWS
3. Add API Gateway as Lambda trigger
4. Add CloudWatch Logs

Reference

[1] AWS Lambda Go, https://github.com/aws/aws-lambda-go

[2] Go ethereum, https://github.com/ethereum/go-ethereum

[3] IPFS, https://ipfs.io/

[4] IPFS API, https://github.com/ipfs/go-ipfs-api

[5] Cross compiling for ethereum, https://github.com/ethereum/go-ethereum/wiki/Cross-compiling-Ethereum

[6] Xgo, https://github.com/karalabe/xgo

[7] Dep, https://github.com/golang/dep

License

MIT