ETH-proxy

ETH-proxy is a complex solution to make proxi-based Ethereum block explorer with built-in LRU cache.

Project based on 2 microservices:

• Proxy-service with Grpc API to cooperate with other microservices
• api-gateway with REST API to cooperate with client applications

Infrastructure scheme

Table of Contents

• Quick start
• Code structure
• Make commands
• CLI
• Dependencies
• Configuration

Quick start

You can simply run this application by using docker compose.

Requirements

• Docker
• Docker Compose

How to

1. clone this repo

   $ clone git@github.com:andskur/eth-proxy.git

2. go to the cloned directory

   $ cd eth-proxy

3. run services with docker-compose

   $ docker-compose up

4. open your browser and go to the Rest API docs - http://localhost:8888/api/v1/docs
5. send http request to the Rest API

   $ curl  localhost:8888/api/v1/block/latest
   {"number":12562832,"hash":"0x0666df9f4a8458c0cf843c6406b1f41c56d7c233be8fdca1a1edecad2f040f90","parent":"0xa131c933e5d1e282fcc3e43980e1ec573c0eeea18e44c70a0f8b20db5f9a3501","timestamp":1622740994,"tx_count":231}

Code structure

|---api - api gateway microservice
|   └---cmd - api gateway CLI commands and app entry points
|   |   └---root - root comand, app entrypoint
|   |   └---serve - command that run microservice
|   |   └---api.go - app entrypoint
|   |
|   └---config - service specific configuration
|   |   └---config.go - config scheme
|   |   └---init.go - default config initialisation
|   |
|   └---format - models to definitions formatters
|   |
|   |---handlers - rest API handlers
|   |
|   |---middlewares rest API middlewares
|   |
|   |---models auto-generated rest api models definitions
|   |
|   |---server auto-generated rest api http server and operations
|   |
|   |---application.go - main api-gatteway app structure with all initialisations
|   |
|   |---swagger.yaml - openapi 2.0 swagger specification
|
|---lib - Grp API wrapper for proxy-service
|
|---models - main models shared between services
|
|---pkg - packages shared between service
|   └---logger - logging wrapper
|   |
|   └---versioner - semver wrapper
|
|---proto - protobuff specifications and generated Go files
|
|---proxy-service - proxy microservice
|   |
|   └---cmd - proxy service CLI commands and app entry points
|   |   └---root - root comand, app entrypoint
|   |   └---serve - command that run microservice
|   |   └---proxy-service.go - app entrypoint
|   |
|   └---config - service specific configuration
|   |   └---config.go - config scheme
|   |   └---init.go - default config initialisation
|   |
|   └---repository - cache storage
|   |   └---cache_blocks.go - blocks caching
|   |   └---cache_txs.go - transactions caching
|   |   └---repository.go - repository pattern interface and its implementations
|   |
|   └---server - Grpc server
|   |   └---handlers.go - Grpc handlers
|   |   └---server.go - Grpc server instance and initialisation
|   |
|   └---service - service business logic
|   |
|   |---application.go - main proxy-service app structure with all initialisations
| 
|---utils - helpers functions

Requirements

• Go v1.16+
• GNU Make
• Swagger
• Docker

Make commands

main Makefile

Used in an active developing process

• make tidy - add missing and remove unused modules dependencies
• make update - update dependencies
• make generate-api - generate API based on swagger specification
• make generate-api-docker - generate API with docker container
• make protoc - generate Go files from proto specification
• make run_service - run proxy-service
• make run_api - run api gateway

proxy-service Makefile

Used in proxy-service building process (commonly in docker container)

• make build - build proxy-service binary
• make clean - delete proxy-service binary
• make image - build proxy-service docker image and tag it with git tag or commit hash
• make image_latest - build proxy-service docker image and tag it as latest

api-gateway Makefile

Used in api-gateway building process (commonly in docker container)

• make build - build api gateway binary
• make generate-api - generate API based on swagger specification* make clean - delete api gateway binary
• make image - build api gateway docker image and tag it with git tag or commit hash
• make image_latest - build proxy-service docker image and tag it as latest

CLI

Available command

Both microservices have one command to run service:

• serve - run service

Global flags

• -c, --config string; config file path (default is ./cfg.yaml)
• --version; show app version message

Dependencies

• go-swagger - full functionality rest api server based on swagger spec
• go-ethereum - interacting with ETHEREUM blockchain
• go-grpc-middleware - collection of grpc middleware
• alice - http middlewares chain
• logrus - logging library
• cobra - library for building CLI commands
• viper - configuration solution

Configuration

Powered by viper package that allow uses different configuration formats for one scheme (env vars preferable).

Proxy service

• Log - logging
  • level - logging level, can be info, warning, error, debug
  • default - info
  • env setup - LOG_LEVEL=
• Grpc - grpc server
  • host - grpc host to connect
    • default - 0.0.0.0
    • env setup - GRPC_HOST=
  • port - grpc port to connect
    • default - 9090
    • env setup - GRPC_PORT=
  • timeout - grpc request default timeout
    • default - 120s
    • env setup - GRPC_TIMEOUT=
• Ethereum - Ethereum params
  • addr - ethereum node address to connect
    • default - https://cloudflare-eth.com
    • env setup - ETHEREUM_ADDR=
  • wss - enable wss mode that allow to listen new mining blocks
    • default - false
    • env setup - ETHEREUM_WSS

API gateway

• Log - logging
  • level - logging level, can be info, warning, error, debug
  • default - info
  • env setup - LOG_LEVEL=
• Cachesize - Blocks and transactions cache size
  • default - 100
  • env setup - CACHESIZE=
• Api - proxy-service Grpc api connection params
  • host - host to service
    • default - profile-service
    • env setup - API_HOST=
  • port - port to service
    • default - 9090
    • env setup - API_PORT=
  • timeout - connection timeout
    • default - 60s
    • env setup - API_TIMEOUT=
• Http - http server
  • host - http host to listen
    • default - 0.0.0.0
    • env setup - HTTP_HOST=
  • port - http port to listen
    • default - 8888
    • env setup - HTTP_PORT=
  • timeout - http request default timeout
    • default - 60s
    • env setup - HTTP_TIMEOUT=