it is but and global error handler even checks that but it does not mean that there could not be middlewares in handlerchain that also decide to write something on their own.
https://github.com/labstack/echo/blob/7f502b1ff10913aeab28abab64f2bf45952c768d/response.go#L56 I'm just warning that you could see that.
that would be a bug in your handler/middleware code
but i would not recommend that. if your requirement is that telemetry should be reported async then run telemetry part in coroutine in that middleware after
next(c) returns.
that snippet your provided takes 5 seconds to respond to the client
even this takes 5 seconds to return a response to the client:
e.GET("/", func(c echo.Context) error {
c.Response().Writer.Write([]byte("hello"))
time.Sleep(5 * time.Second)
return nil
}) e.Use(func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) error {
// gather stats before
err := next(c)
// gather telemetry after
go func() {
time.Sleep(1 * time.Second) // do work, and report without affecting client
fmt.Println("reporting telemetry")
}()
return err
}
})
but you need to recover panics in that coroutine or whole application will shutdown/crash on panic
I am using AWS Cognito for user authentication to my API. Obviously the user can spoof GET/POST/etc params. So far I have created a middleware to validate the JWT token, which gives me access to the true user values, for example their account ID. What's the best practice for validating these? I think I'd like to store the user's true details somewhere so that I can validate it based on the resource they are calling, but not sure if that belongs in the context or somewhere else. Any ideas?
in context with
c.Set(). This is standard way to pass information from middleware to middleware and to handler. Ala JWT uses it store token in request context https://github.com/labstack/echo/blob/7f502b1ff10913aeab28abab64f2bf45952c768d/middleware/jwt.go#L234
Re: https://echo.labstack.com/middleware/rate-limiter/
How do I use this? I want a basic rate limiter and hence using the following:
e.Use(middleware.RateLimiter(middleware.NewRateLimiterMemoryStore(4)))
ON compilation:
./ari.go:55:8: undefined: middleware.RateLimiter
./ari.go:55:31: undefined: middleware.NewRateLimiterMemoryStore
How do i import the RateLimiter function?
@aldas @trendeeze_twitter @pablodz @adayNU_twitter
Only this
e := echo.New()
e.Use(middleware.LoggerWithConfig(middleware.LoggerConfig{
does that request have
Content-Length header?
4 replies
Hi! I'm using echo with oapi validate middleware to check incoming request parameters against a regex in an OpenApi specification file. When a parameter does not match the regex a message it's shown with the correct regex for that parameter. The problem I'm having is that the slashes in the regex string are escaped multiple times. I think that when opai_validate generates the error message it prints the regex with
%q so the single slash is escaped there. And then when echo prints the message the same thing happens and each slash is escaped again, making a single slash into four. Does anyone have an idea on how to deal with this?
Set your debugger breakpoint here https://github.com/deepmap/oapi-codegen/blob/d819e1dea68f9bf0118ab2138e1bb57c8d3de2f9/pkg/middleware/oapi_validate.go#L103 and check what that e.reason value is.
and maybe another breakpoint here https://github.com/labstack/echo/blob/c6f0c667f145b5e5347ba812c9de5a5a4280bac5/echo.go#L371 and you probably will see here things go south
If you do not have experience with debugger then maybe https://www.digitalocean.com/community/tutorials/debugging-go-code-with-visual-studio-code helps. assuming you are using vscode.
Part of the problem seems to be Echo returns the string raw without processing its characters...? I'm not entirely sure. But modifying the error message and inserting tab characters
\t makes those characters appear directly in the response instead of being processed, so I'm guessing something happens there and an escaped backslash \\ in the string is returned as-is
Assuming that error ends up in global error handler. then it is sent to client by that line https://github.com/labstack/echo/blob/c6f0c667f145b5e5347ba812c9de5a5a4280bac5/echo.go#L400 if that message is already been escaped some characters will be double escaped to be valid json string value.
the field that is returning as base64 is a []byte in the struct
see https://pkg.go.dev/encoding/json#Marshal
Array and slice values encode as JSON arrays, except that []byte encodes as a base64-encoded string, and a nil slice encodes as the null JSON value.
How to use a gRPC service with echo framework. I have the same question from: https://stackoverflow.com/questions/67558481/how-to-use-grpc-with-golang-echo-framework
just implement layered architecture in our application and design HTTP and GRPC handlers in your transport layer that extract their data and pass it t your business service layer.
search for "Onion Architecture" / "Hexagonal Architecture"