swan_lib

README

Why I Built This

Swan_lib was created to help Go developers handle JWT authentication, CORS, and common API tasks easily when working with net/http. I built this because, while working on my own microservice for a portfolio project, I found myself repeating the same code too often. Instead of getting frustrated, I wrote this library to save time, reduce complexity, and focus on the actual business logic.

I haved tested the JWT middleware and I believe also the CORS will work

Available Methods in swan_lib

Here’s a quick rundown of what swan_lib offers to simplify your API development with net/http:

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JWT Methods

• NewJWTManager(secretKey string, duration time.Duration)
  Create a manager for generating and verifying JWTs with a secret key and expiration duration.

• GenerateToken(userID string, customClaims map[string]any)
  Generate a JWT with a user ID and optional custom claims.

• NewJWTMiddleware(secretKey string)
  Set up middleware to validate JWTs on protected routes.

• Authorize(next http.Handler)
  Middleware that checks if a valid JWT is present in the request.

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CORS Methods

• NewCORSMiddleware()
  Create a CORS middleware to handle cross-origin requests.

• AllowOrigins(origins []string)
  Specify allowed origins for CORS.

• AllowMethods(methods []string)
  Define allowed HTTP methods (GET, POST, etc.) for CORS.

• AllowHeaders(headers []string)
  Set which headers are allowed in CORS requests.

• AllowCredentials(allowed bool)
  Allow or disallow credentials in cross-origin requests.

• Handler(next http.Handler)
  Apply CORS settings to the provided handler.

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General Utilities

• JSONResponse(w http.ResponseWriter, status int, data any)
  Send a JSON response with the given status and data.

• ErrorResponse(w http.ResponseWriter, status int, message string, err error)
  Send a standard error response.

• ParseBody(r http.Request, target any)
  Parse the request body into the provided struct.

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Installation

To get started with swan_lib, run the following command:

go get github.com/SwanHtetAungPhyo/swan_lib

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Documentation

Index

• Constants
• func ErrorResponse(w http.ResponseWriter, status int, message string, err error)
• func JSONResponse(w http.ResponseWriter, status int, message string, data any)
• func ParseBody(r *http.Request, target any) error
• type CORSMiddleware
  • func NewCORSMiddleware() *CORSMiddleware
  • func (c *CORSMiddleware) AllowHeaders(headers []string) *CORSMiddleware
  • func (c *CORSMiddleware) AllowMethods(methods []string) *CORSMiddleware
  • func (c *CORSMiddleware) AllowOrigins(origins []string) *CORSMiddleware
  • func (c *CORSMiddleware) Handler(next http.Handler) http.Handler
• type ErrorResponseStruct
• type GlobalJWTMiddleware
  • func NewJWTMiddleware(secretKey string) *GlobalJWTMiddleware
  • func (j *GlobalJWTMiddleware) Authorize(next http.Handler) http.Handler
  • func (j *GlobalJWTMiddleware) FastAuthorize(next fasthttp.RequestHandler) fasthttp.RequestHandler
  • func (j *GlobalJWTMiddleware) FiberAuthorize() fiber.Handler
• type GlobalResponse
• type GraceFulShutDown
  • func New() *GraceFulShutDown
  • func (g *GraceFulShutDown) AddTask(task func(ctx context.Context) error)
  • func (g *GraceFulShutDown) Run(timeout time.Duration)
• type JWTManager
  • func NewJWTManager(secretKey string, duration time.Duration) *JWTManager
  • func (j *JWTManager) GenerateToken(userID string, customClaims map[string]any) (string, error)

Constants

const (
	ORIGIN_CONTROL      = "Access-Control-Allow-Origin"
	METHOD_CONTROL      = "Access-Control-Allow-Methods"
	HEADER_CONTROL      = "Access-Control-Allow-Headers"
	CREDENTIALS_CONTROL = "Access-Control-Allow-Credentials"
)

Functions

func ErrorResponse

func ErrorResponse(w http.ResponseWriter, status int, message string, err error)

func JSONResponse

func JSONResponse(w http.ResponseWriter, status int, message string, data any)

func ParseBody

func ParseBody(r *http.Request, target any) error

Types

type CORSMiddleware

type CORSMiddleware struct {
	AllowedOrigins   []string
	AllowedMethods   []string
	AllowedHeaders   []string
	AllowCredentials bool
}

func NewCORSMiddleware

func NewCORSMiddleware() *CORSMiddleware

func (*CORSMiddleware) AllowHeaders

func (c *CORSMiddleware) AllowHeaders(headers []string) *CORSMiddleware

func (*CORSMiddleware) AllowMethods

func (c *CORSMiddleware) AllowMethods(methods []string) *CORSMiddleware

func (*CORSMiddleware) AllowOrigins

func (c *CORSMiddleware) AllowOrigins(origins []string) *CORSMiddleware

func (*CORSMiddleware) Handler

func (c *CORSMiddleware) Handler(next http.Handler) http.Handler

type ErrorResponseStruct

type ErrorResponseStruct struct {
	Error   error  `json:"error"`
	Message string `json:"message"`
	Status  int    `json:"status"`
}

type GlobalJWTMiddleware

type GlobalJWTMiddleware struct {
	Secret string
}

func NewJWTMiddleware

func NewJWTMiddleware(secretKey string) *GlobalJWTMiddleware

func (*GlobalJWTMiddleware) Authorize

func (j *GlobalJWTMiddleware) Authorize(next http.Handler) http.Handler

func (*GlobalJWTMiddleware) FastAuthorize

func (j *GlobalJWTMiddleware) FastAuthorize(next fasthttp.RequestHandler) fasthttp.RequestHandler

func (*GlobalJWTMiddleware) FiberAuthorize

func (j *GlobalJWTMiddleware) FiberAuthorize() fiber.Handler

type GlobalResponse

type GlobalResponse struct {
	Message string `json:"message"`
	Body    any    `json:"body"`
}

type GraceFulShutDown

type GraceFulShutDown struct {
	// contains filtered or unexported fields
}

func New

func New() *GraceFulShutDown

func (*GraceFulShutDown) AddTask

func (g *GraceFulShutDown) AddTask(task func(ctx context.Context) error)

func (*GraceFulShutDown) Run

func (g *GraceFulShutDown) Run(timeout time.Duration)

type JWTManager

type JWTManager struct {
	SecretKey     string
	TokenDuration time.Duration
}

func NewJWTManager

func NewJWTManager(secretKey string, duration time.Duration) *JWTManager

func (*JWTManager) GenerateToken

func (j *JWTManager) GenerateToken(userID string, customClaims map[string]any) (string, error)