> ada

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Context ​

Handlers are typically func(w http.ResponseWriter, r *http.Request), but ada provides a wrapper called ada.HandlerFunc which is func(c *ada.Context) error. This adds useful methods to handle requests and responses more easily.

go
func myHandler(c *ada.Context) error {
    var data MyData
    if err := c.Bind(&data); err != nil { // parse request body based on Content-Type
        return c.SetStatus(http.StatusBadRequest).Err(err)
    }

    // default status is 200 OK
    return c.SetHeader("X-Custom-Header", "value").SetStatus(http.StatusOK).SendJSON(data)
}

Response Methods ​

JSON Responses ​

Send JSON data with automatic content-type setting:

go
// Send compact JSON
return c.SendJSON(data)

// Send pretty-printed JSON
return c.SendJSONP(data, "  ")

// Send raw JSON bytes
return c.SendJSONRaw(bytes.NewReader([]byte(`{"message": "hello"}`)))

String Responses ​

Send plain text responses:

go
return c.SendString("Hello, World!")

File Responses ​

Send single files or multiple files as ZIP:

go
// Send single file
file, _ := os.Open("example.txt")
defer file.Close()
return c.SendFile("example.txt", file)

// Send multiple files as ZIP
files := map[string]io.Reader{
    "file1.txt": strings.NewReader("content1"),
    "file2.txt": strings.NewReader("content2"),
}
return c.SendZip("archive.zip", files)

Blob Responses ​

Send binary data with custom content-type:

go
data := []byte("binary content")
return c.SendBlob("application/octet-stream", bytes.NewReader(data))

No Content ​

Send 204 No Content response:

go
return c.SendNoContent()

Headers and Status ​

Set response headers and status codes fluently:

go
return c.SetHeader("X-Custom-Header", "value").
       SetStatus(http.StatusCreated).
       SendJSON(data)

Error Handling ​

ada.HandlerFunc returns an error, which can be handled by a custom error handler set on the server:

go
server := ada.New()
server.ErrorHandler(func(c *ada.Context, err error) {
    // Custom error handling logic
    log.Printf("Error: %v", err)
    c.SetStatus(http.StatusInternalServerError).SendJSON(map[string]string{
        "error": "Internal server error",
    })
})

The default error handler checks if the error is an ada.HandlerError and uses its Code field as the HTTP status:

go
var DefaultErrHandler = func(c *ada.Context, err error) {
	var errResp *ada.HandlerError
	if errors.As(err, &errResp) {
		c.SetStatus(errResp.Code).SendJSON(errResp)
		return
	}

	c.SetStatus(http.StatusInternalServerError).SendJSON(map[string]string{"message": err.Error()})
}

To return a HandlerError with a specific status code:

go
func myHandler(c *ada.Context) error {
    return c.SetStatus(http.StatusBadRequest).Err(errors.New("id is required"))
}

This will return a 400 Bad Request with the error message in JSON format.