kwakubiney / seshat

A gRPC server that keeps metrics of your services

Seshat

A gRPC server that keeps metrics of your services.

Motivation

I built Seshat in an attempt to deapen my understanding of gRPC although it currently has the potential to be a library independent of gRPC. The idea of Seshat is to help you easily create metrics for your services. You can easily configure your gRPC server to send ping all your services and keep records of the latency for later analysis.

Usage

1. Run the command git clone https://github.com/quamejnr/seshat
2. From the root directory, run the command go run metrics-server/main.go to start the server
3. Open another terminal and run the command go run metrics-client/main.go to start the client. You can provide your own url as a flag, it defaults to https://google.com. Run go run metrics-client/main.go to see the flags available.
4. Make a couple of requests and then run curl localhost:8000/metrics | json_pp to see some metrics.

Create metrics

There are currently two categories of metrics: - CounterMetric which can be used to keep count or fixed value. - MapMetric which can be used to keep track of a key, value pair.

MapMetric

The below example has already been implemented in this code.

1. You can create a MapMetric by creating an instance of MapMetric and providing the name of your metric. For example:

var l = NewMapMetric("LatencyMetrics")

2. You can then write your own function and use this instance created. Currently, MapMetric has only one method SetLabelValue(label string, value any). For example;

var l = NewMapMetric("LatencyMetrics")

func recordLatency(url string, responseTime float32) {
    l.SetLabelValue(url, responseTime)
}

3. You can use your function to keep metrics of your requests latency. You should see your created metric in your metrics when you run curl localhost:8000/metrics | json_pp.

CounterMetric

The below example has already been implemented in this code.

1. You can create a CounterMetric using the function NewCounterMetric.

var c = NewCounterMetric{"requestCounter"}

2. You can write your own function leveraging the methods from the instance created. Currently, CounterMetric has 3 methods; SetValue, Increment, Decrement.

var c = NewCounterMetric{"requestCounter"}

func recordRequests() {
    c.Increment()
}

3. You can use your function to keep metrics of your requests latency. You should see your created metric in your metrics when you run curl localhost:8000/metrics | json_pp.

Future Plans

• Add tests
• Make it a standalone library.

Contributing

Contributions to Seshat are welcome! If you find a bug, have an idea for an improvement, or want to add a new feature, please open an issue or create a pull request on the Heimdall GitHub repository.

License

Seshat is open-source software licensed under the MIT License. You are free to use, modify, and distribute this tool according to the terms of the license.