Overview

Teffy is a library for reading & writing Google Chrome Trace Event Format files in Go.

Quickstart

Install

go get github.com/omaskery/teffy

The package is split into three main parts:

• events - the logical representation of trace events
• io - the ability to read/write events to files (including streaming)
• utils/trace - opinionated utilities for generating traces

Reading Events

package main

import (
    "fmt"
    "os"
    
    tio "github.com/omaskery/teffy/pkg/io"
)

func main() {
    f, _ := os.Open("some.trace")
    defer f.Close()

    trace, _ := tio.ParseJsonObj(f)

    for _, event := range trace.Events() {
        fmt.Printf("- %v\n", event)
    }
}

Writing Events

package main

import (
    "os"
    
    "github.com/omaskery/teffy/pkg/events"
    tio "github.com/omaskery/teffy/pkg/io"
)

func main() {
    f, _ := os.OpenFile("some.trace", os.O_RDWR, os.ModePerm)
    defer f.Close()

    data := tio.TefData{}
    data.Write(&events.BeginDuration{
        Name: "my event",
        Categories: []string{ "cool", "categories" },
        Timestamp: 0,
    })
    // your amazing code
    data.Write(&events.EndDuration{
        Name: "my event",
        Categories: []string{ "cool", "categories" },
        Timestamp: 100,
    })

    _ = tio.WriteJsonObject(f, data)
}

Opinionated Event Writing Utilities

package main

import (
    "github.com/omaskery/teffy/pkg/util/trace"
)

func main() {
    t, _ := trace.TraceToFile("some.trace")
    defer t.Close()
    
    defer t.BeginDuration("my event", trace.WithCategories("cool", "categories")).End()

    // your amazing code
    t.Instant("wow a thing happened!", trace.WithStackTrace())
}