Proglog

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Auto-generated by the devscriber command-line tool.

This GitHub repo has code examples from the Distributed Services with Go O'Reilly book by Travis Jeffrey.

Initial Setup

After cloning the repo, run the following:

make init
make gencert
make compile

Usage

To run the program's API, execute the command below from proglog/cmd/server:

$ go run main.go

POST new records to the log:

$ curl -X POST localhost:8080 -d '{"record": {"value": "TGV0J3MgR28gIzEK"}}'
​$ curl -X POST localhost:8080 -d '{"record": {"value": "TGV0J3MgR28gIzIK"}}'
$ curl -X POST localhost:8080 -d '{"record": {"value": "TGV0J3MgR28gIzMK"}}'

GET records from the log:

 curl -X GET localhost:8080 -d '{"offset": [RECORD_OFFSET_#]}'

Testing

make test

Features

The project's features are as follows:

⭐ Chapter 1: JSON/HTTP commit log service that stores and retrieves records from an in-memory log.
⭐ Chapter 2: Protobuf fundamentals and using them to create a protocol buffer for the Record type.
⭐ Chapter 3: Writing a custom log package
⭐ Chapter 4: Serve Requests w/ gRPC
⭐ Chapter 5: Securing the Service w/ Mutual TLS Authentication
⭐ Chapter 6: Observing the System
⭐ Chapter 7: Adding Service Discovery
⭐ Chapter 8: Implementing Raft
⭐ Chapter 9: Discover Servers and Load Balance from the Client

Notes

• Chapter 5 uses go get to install the cfssl tools. If this doesn't work, I recommend using sudo apt install golang-cfssl and sudo apt install golang-cfssljson.
• Observability - a measure of how well we understand a system's behavior or state based on external outputs.
• Types of Telemetry
  1. Metrics - measure numeric data over time (counters, histograms, gauges).
     • Google's 4 Golden Signals - latency, errors, traffic, saturation (L.E.T.S.).
  2. Structured logs - descriptions of events that have occurred in a system.
  3. Traces - details the request lifecycle as it flows through the system.
• Chapter 9: Load balancing strategies
  1. Server Proxying
  2. External Load Balancing
  3. Client-side Balancing

License

None