flamego-sentry

Package flamego-sentry is a middleware that capture and handle the error with Sentry for Flamego

Install

go get github.com/asjdf/flamego-sentry

import (
    "fmt"
    "github.com/getsentry/sentry-go"
    sentryflame "github.com/asjdf/flamego-sentry"
    "github.com/flamego/flamego"
)

// To initialize Sentry's handler, you need to initialize Sentry itself beforehand
if err := sentry.Init(sentry.ClientOptions{
    Dsn: "your-public-dsn",
}); err != nil {
    fmt.Printf("Sentry initialization failed: %v\n", err)
}

// Then create your app
f := flamego.Classic()

// Once it's done, you can attach the handler as one of your middleware
f.Use(sentryflame.New(sentryflame.Options{}))

// Set up routes
f.Get("/", func() string {
    return "Hello world!"
})

// And run it
f.Run()

Configuration

sentryflame accepts a struct of Options that allows you to configure how the handler will behave.

Currently it respects 3 options:

// Whether Sentry should repanic after recovery, in most cases it should be set to true,
// as flamego.Classic includes its own Recovery middleware that handles http responses.
Repanic         bool
// Whether you want to block the request before moving forward with the response.
// Because Flamego's default `Recovery` handler doesn't restart the application,
// it's safe to either skip this option or set it to `false`.
WaitForDelivery bool
// Timeout for the event delivery requests.
Timeout         time.Duration

Usage

sentryflame invoke an instance of *sentry.Hub (https://godoc.org/github.com/getsentry/sentry-go#Hub) to the flamego.Context, which makes it available throughout the rest of the request's lifetime. You can access it by using the sentrygin.GetHubFromContext() method on the context itself in any of your proceeding middleware and routes. And it should be used instead of the global sentry.CaptureMessage, sentry.CaptureException, or any other calls, as it keeps the separation of data between the requests.

Keep in mind that *sentry.Hub won't be available in middleware attached before to sentryflame!

f := flamego.Classic()

f.Use(sentryflame.New(sentrygin.Options{
    Repanic: true,
}))

f.Use(func(ctx flamego.Context) {
    if hub := sentryflame.GetHubFromContext(ctx); hub != nil {
        hub.Scope().SetTag("someRandomTag", "maybeYouNeedIt")
    }
    ctx.Next()
})

f.Get("/1", func(ctx flamego.Context) {
    if hub := GetHubFromContext(ctx); hub != nil {
        hub.WithScope(func(scope *sentry.Scope) {
            scope.SetExtra("unwantedQuery", "someQueryDataMaybe")
            hub.CaptureMessage("User provided unwanted query string, but we recovered just fine")
        })
    }
    ctx.ResponseWriter().WriteHeader(http.StatusOK)
})

f.Get("/2", func(ctx flamego.Context, hub *sentry.Hub) {
    hub.WithScope(func(scope *sentry.Scope) {
        scope.SetExtra("unwantedQuery", "someQueryDataMaybe")
        hub.CaptureMessage("User provided unwanted query string, but we recovered just fine")
    })
    ctx.ResponseWriter().WriteHeader(http.StatusOK)
})

f.Get("/foo", func() {
    // sentrygin handler will catch it just fine. Also, because we attached "someRandomTag"
    // in the middleware before, it will be sent through as well
    panic("y tho")
})

app.Run()

Accessing Request in BeforeSend callback

sentry.Init(sentry.ClientOptions{
    Dsn: "your-public-dsn",
    BeforeSend: func(event *sentry.Event, hint *sentry.EventHint) *sentry.Event {
        if hint.Context != nil {
            if req, ok := hint.Context.Value(sentry.RequestContextKey).(*http.Request); ok {
                // You have access to the original Request here
            }
        }

        return event
    },
})