Som | Add web routing capabilities

Author: isomnath

router/web/router.go

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+package web
+
+import (
+	"net/http"
+
+	"github.com/isomnath/belvedere/config"
+	"github.com/isomnath/belvedere/handlers"
+
+	ddTracerMux "gopkg.in/DataDog/dd-trace-go.v1/contrib/gorilla/mux"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
+)
+
+type Route struct {
+	Name            string
+	Path            string
+	Middlewares     []Middleware
+	HandlerFunction http.HandlerFunc
+	Method          string
+}
+
+type Middleware struct {
+	Function func(http.HandlerFunc) http.HandlerFunc
+}
+
+// Initialize - Returns a fully qualified mux router
+func Initialize(routes []Route) *ddTracerMux.Router {
+	router := ddTracerMux.NewRouter()
+
+	router.HandleFunc(config.GetAppHealthCheckAPIPath(), baseResponseHeaderMiddleware(handlers.Ping)).Methods(http.MethodGet)
+	router.NotFoundHandler = baseResponseHeaderMiddleware(handlers.RouteNotFoundHandler)
+
+	for _, route := range routes {
+		composedHandlerFunc := attachMiddlewares(route.Middlewares, route.HandlerFunction)
+		router.HandleFunc(route.Path, baseResponseHeaderMiddleware(composedHandlerFunc)).Methods(route.Method)
+	}
+
+	return router
+}
+
+func attachMiddlewares(middlewares []Middleware, handlerFunc http.HandlerFunc) http.HandlerFunc {
+	if middlewares == nil || len(middlewares) < 1 {
+		return handlerFunc
+	}
+	composedHandlerFunc := handlerFunc
+	for _, middleware := range middlewares {
+		composedHandlerFunc = attachMiddleware(middleware, composedHandlerFunc)
+	}
+	return composedHandlerFunc
+}
+
+func attachMiddleware(middleware Middleware, handlerFunc http.HandlerFunc) http.HandlerFunc {
+	composedHandlerFunc := middleware.Function(handlerFunc)
+	return composedHandlerFunc
+}
+
+func baseResponseHeaderMiddleware(next http.HandlerFunc) http.HandlerFunc {
+	return func(writer http.ResponseWriter, request *http.Request) {
+		span, ctx := tracer.StartSpanFromContext(request.Context(), "http.request", tracer.ResourceName(request.URL.Path))
+		request.WithContext(ctx)
+		user := request.Header.Get("username")
+		tracer.SetUser(span, user, tracer.WithUserEmail(user))
+		writer.Header().Set("Content-Type", "application/json")
+		next(writer, request)
+		span.Finish()
+	}
+}

router/web/router_test.go

@@ -0,0 +1,66 @@
+package web
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/isomnath/belvedere/config"
+	"github.com/isomnath/belvedere/instrumentation"
+
+	"github.com/stretchr/testify/suite"
+)
+
+type WebRouterTestSuite struct {
+	suite.Suite
+}
+
+func (suite *WebRouterTestSuite) SetupSuite() {
+	config.LoadBaseConfig()
+	instrumentation.StartDDTracer()
+}
+
+func (suite *WebRouterTestSuite) TearDownSuite() {
+	instrumentation.StopDDTracer()
+}
+
+func MyTestHandlerFunc(rw http.ResponseWriter, r *http.Request) {
+	rw.Write([]byte(`{"success": true, "data": {"message": "successful"}}`))
+}
+
+func (suite *WebRouterTestSuite) TestInitialize() {
+	routesWithoutMiddleware := []Route{{
+		Name:            "Test Route",
+		Path:            "/test_route_1",
+		Middlewares:     nil,
+		HandlerFunction: MyTestHandlerFunc,
+		Method:          http.MethodGet,
+	}}
+
+	routesWithMiddleware := []Route{{
+		Name:            "Test Route",
+		Path:            "/test_route_2",
+		Middlewares:     []Middleware{{Function: myTestMiddlewareFuncOne}, {Function: myTestMiddlewareFuncTwo}},
+		HandlerFunction: MyTestHandlerFunc,
+		Method:          http.MethodPut,
+	}}
+
+	suite.NotNil(Initialize(routesWithoutMiddleware))
+	suite.NotNil(Initialize(routesWithMiddleware))
+
+}
+
+func myTestMiddlewareFuncOne(next http.HandlerFunc) http.HandlerFunc {
+	return func(rw http.ResponseWriter, r *http.Request) {
+		next(rw, r)
+	}
+}
+
+func myTestMiddlewareFuncTwo(next http.HandlerFunc) http.HandlerFunc {
+	return func(rw http.ResponseWriter, r *http.Request) {
+		next(rw, r)
+	}
+}
+
+func TestWebRouterTestSuite(t *testing.T) {
+	suite.Run(t, new(WebRouterTestSuite))
+}