smesh

Read Me

A Service Mesh is a structured network of communicating services.

This implementation here consists of three major layers.

• Master-Layer
• Sidecar-Layer
• Service-Layer

This project is written in GoLang and uses Protocol Buffers in combination with gRPC. ^1^3

Go does not include all the needed libraries by default.

Needed installations:

go get google.golang.org/grpc

This Project consists of three main parts:

1) Client

The Client receives data from many different data sources: sensors, open data interfaces etc...

It can save messages which could not be send because of connection errors and also connect to other sidecars if the previous one has a failure.

The Client can be started by using: (/cmd)

go run clientMain.go

All the executable .go-files lie in the main package in the directory /cmd (goLang guidelines)

To operate the client needs multiple files, including: (/files)

• safeData.csv

  This file stores all messages which could not be send because of network errors.

• clientCon.csv

  ClientCon is the file which stores the IP-addresses of all the possible sidecars the client can connect to. Entries can be added manually.

Sidecar3;192.168.14.123:9000;
Sidecar4;192.168.33.156:9000;

<sidecar ID>;IP-address;

To establish a connection the client also needs access to the compiled Protobuf Files sidecar.pb.go and sidecar_grpc.pb.go

sidecar.proto can be compiled with:

 	//old Proto-Version
    /path/to/binary/protoc.exe (protoc) --		go_out=plugins=grpc:<foldername> ./<filename>.proto
    
    //new Proto-Version
    protoc --go_out=<foldername> <filename>.proto

Before compiling, the following Libraries should be installed:

go install google.golang.org/protobuf/cmd/protoc-gen-go

2) Sidecar

The sidecar is a proxy which receives the message from and hands it off to the master. The sidecars are also able to find a new master if the previous one breaks down. Each sidecar also saves the metadata of all clients which have previously created a connection. So that it can initiate health checks where the stats of the services is tested.

A sidecar can be started with: (/cmd)

go run sidecarMain.go

To operate the sidecar needs the following files: (/sidecar)

• sidecarServer.go

  The server receives the messages from the clients and starts a new client which pushes the data to the next service in line.

• sidecarCom.go

  The sidecarCom file defines the different gRPC functions which clients can invocate

• sidecarClient.go

  The clients receives the data from the server and sends it to the masters

• sidecar.pb.go

  Generated file for GRPC communication

• sidecar_grpc.pb.go

  Generated file for GRPC communication

3) Server (Master)

The Master receives the messages from the sidecar proxies and publishes them to to Kafka. The master also saves meta data of all sidecars which established a connection. The master can also initiate health-checks through the saved metadata.

The master can be started with: (cmd)

go run masterMain.go

To operate, the server needs the following files: (/chat)

• chat2.go

  Chat2 holds all the gRPC communication functions.

• chat2.pb.go

  Generated file for GRPC communication

• chat2.proto

  Generated file for GRPC communication

• server.go

  Starts the gRPC Server

Tests

The test are in the directory /tests. Each class has its own test file.

All tests can be started with:

go test

Passed tests look like this:

PASS
ok      github.com/Open-Twin/CityMesh-ProtoTypes/Jakob_GRPC/test        1.052s

Healthchecks

Work in Progress

/cmd

MASTER

SIDECAR

go run masterHeartBeat.go

healthChechReport.csv

  ID: S123 IP Addr: 172.217.22.196 receive, RTT: 17.7742ms;
  ID: S12 IP Addr: 172.217.22.196 receive, RTT: 18.0854ms; 
  ID: S1234 IP Addr: 172.217.22.196 receive, RTT: 29.1553ms;