gofr-dev/gofr

package main

import (
    "time"

    "gofr.dev/pkg/gofr"
)

// This example simulates the usage of custom metrics for transactions of an ecommerce store.

const (
    transactionSuccessful = "transaction_success"
    transactionTime       = "transaction_time"
    totalCreditDaySales   = "total_credit_day_sale"
    productStock          = "product_stock"
)

func main() {
    // Create a new application
    a := gofr.New()

    a.Metrics().NewCounter(transactionSuccessful, "used to track the count of successful transactions")
    a.Metrics().NewUpDownCounter(totalCreditDaySales, "used to track the total credit sales in a day")
    a.Metrics().NewGauge(productStock, "used to track the number of products in stock")
    a.Metrics().NewHistogram(transactionTime, "used to track the time taken by a transaction",
        5, 10, 15, 20, 25, 35)

    // Add all the routes
    a.POST("/transaction", TransactionHandler)
    a.POST("/return", ReturnHandler)

    // Run the application
    a.Run()
}

func TransactionHandler(c *gofr.Context) (interface{}, error) {
    transactionStartTime := time.Now()

    // transaction logic

    c.Metrics().IncrementCounter(c, transactionSuccessful)

    tranTime := time.Now().Sub(transactionStartTime).Milliseconds()

    c.Metrics().RecordHistogram(c, transactionTime, float64(tranTime))
    c.Metrics().DeltaUpDownCounter(c, totalCreditDaySales, 1000, "sale_type", "credit")
    c.Metrics().SetGauge(productStock, 10)

    return "Transaction Successful", nil
}

func ReturnHandler(c *gofr.Context) (interface{}, error) {
    // logic to create a sales return
    c.Metrics().DeltaUpDownCounter(c, totalCreditDaySales, -1000, "sale_type", "credit_return")

    // Update the Gauge metric for product stock
    c.Metrics().SetGauge(productStock, 50)

    return "Return Successful", nil
}