Context (Ctx)¶

Request context with helpers for clean handler code.

Properties¶

c.Request    *http.Request
c.Writer     http.ResponseWriter

Response Methods¶

JSON Response¶

c.JSON(code int, v any) error
c.OK(v any) error           // 200
c.Created(v any) error      // 201

Text Response¶

c.Text(code int, text string) error

HTML Response¶

c.HTML(code int, html string) error

Binary Response¶

c.Blob(code int, contentType string, data []byte) error

Stream Response¶

c.Stream(code int, contentType string, r io.Reader) error

No Content¶

c.NoContent() error         // 204

Error Responses¶

c.BadRequest(message string) error    // 400
c.Unauthorized(message string) error  // 401
c.Forbidden(message string) error     // 403
c.NotFound(message string) error      // 404
c.ServerError(message string) error   // 500

Status & Headers¶

c.Status(code int) *Ctx
c.StatusCode() int
c.Header(key, value string) *Ctx
c.GetHeader(key string) string
c.Written() bool
c.Redirect(code int, url string) error

Request Data¶

Path Parameters¶

c.Param(name string) string
c.ParamInt(name string) int
c.ParamInt64(name string) int64

Query Parameters¶

c.Query(name string) string
c.QueryInt(name string) int
c.QueryInt64(name string) int64
c.QueryBool(name string) bool
c.QueryDefault(name, def string) string
c.QueryValues(name string) []string
c.QueryParams() url.Values

Body Binding¶

c.Bind(v any) error
c.BindValid(v any, validate func() error) error

Bind() supports multiple content types:

application/json - JSON body
application/x-www-form-urlencoded - Form data
multipart/form-data - Multipart form data

Form & Files¶

c.FormValue(name string) string
c.File(name string) (*multipart.FileHeader, error)

Cookies¶

c.Cookie(name string) string
c.SetCookie(cookie *http.Cookie)

Request Helpers¶

c.Method() string
c.Path() string
c.ClientIP() string
c.Bearer() string
c.RequestID() string
c.IsJSON() bool
c.IsAJAX() bool
c.Context() context.Context

Request-Scoped Storage¶

c.Set(key string, value any)
c.Get(key string) any
c.GetString(key string) string
c.GetInt(key string) int
c.GetBool(key string) bool

Examples¶

JSON API Handler¶

func getUser(c *marten.Ctx) error {
    id := c.ParamInt("id")
    user, err := db.FindUser(id)
    if err != nil {
        return c.NotFound("user not found")
    }
    return c.OK(user)
}

Streaming Response¶

func downloadFile(c *marten.Ctx) error {
    file, err := os.Open("large-file.zip")
    if err != nil {
        return c.NotFound("file not found")
    }
    defer file.Close()

    c.Header("Content-Disposition", "attachment; filename=file.zip")
    return c.Stream(200, "application/octet-stream", file)
}

HTML Response¶

func homePage(c *marten.Ctx) error {
    html := "<html><body><h1>Welcome</h1></body></html>"
    return c.HTML(200, html)
}

Form Handling¶

func createPost(c *marten.Ctx) error {
    title := c.FormValue("title")
    file, err := c.File("image")
    if err != nil {
        return c.BadRequest("image required")
    }
    // Process...
    return c.Created(marten.M{"id": newID})
}

Request Validation¶

func createUser(c *marten.Ctx) error {
    var input struct {
        Name  string `json:"name"`
        Email string `json:"email"`
    }

    if err := c.BindValid(&input, func() error {
        if input.Name == "" {
            return &marten.BindError{Message: "name required"}
        }
        return nil
    }); err != nil {
        return c.BadRequest(err.Error())
    }

    return c.Created(input)
}