Init simple Go React blog with Goxygen

simple-blog/server/db/db.go

@@ -0,0 +1,36 @@
+package db
+
+import (
+	"database/sql"
+	"simple-blog/model"
+)
+
+type DB interface {
+	GetTechnologies() ([]*model.Technology, error)
+}
+
+type PostgresDB struct {
+	db *sql.DB
+}
+
+func NewDB(db *sql.DB) DB {
+	return PostgresDB{db: db}
+}
+
+func (d PostgresDB) GetTechnologies() ([]*model.Technology, error) {
+	rows, err := d.db.Query("select name, details from technologies")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var tech []*model.Technology
+	for rows.Next() {
+		t := new(model.Technology)
+		err = rows.Scan(&t.Name, &t.Details)
+		if err != nil {
+			return nil, err
+		}
+		tech = append(tech, t)
+	}
+	return tech, nil
+}

simple-blog/server/go.mod

@@ -0,0 +1,5 @@
+module simple-blog
+
+go 1.22
+
+require github.com/lib/pq v1.10.9

simple-blog/server/go.sum

@@ -0,0 +1,2 @@
+github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
+github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=

simple-blog/server/model/technology.go

@@ -0,0 +1,6 @@
+package model
+
+type Technology struct {
+	Name    string `json:"name"`
+	Details string `json:"details"`
+}

simple-blog/server/server.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"database/sql"
+	"log"
+	"os"
+	"simple-blog/db"
+	"simple-blog/web"
+
+	_ "github.com/lib/pq"
+)
+
+func main() {
+	d, err := sql.Open("postgres", dataSource())
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer d.Close()
+	// CORS is enabled only in prod profile
+	cors := os.Getenv("profile") == "prod"
+	app := web.NewApp(db.NewDB(d), cors)
+	err = app.Serve()
+	log.Println("Error", err)
+}
+
+func dataSource() string {
+	host := "localhost"
+	pass := "pass"
+	if os.Getenv("profile") == "prod" {
+		host = "db"
+		pass = os.Getenv("db_pass")
+	}
+	return "postgresql://" + host + ":5432/goxygen" +
+		"?user=goxygen&sslmode=disable&password=" + pass
+}

simple-blog/server/web/app.go

@@ -0,0 +1,63 @@
+package web
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"simple-blog/db"
+)
+
+type App struct {
+	d        db.DB
+	handlers map[string]http.HandlerFunc
+}
+
+func NewApp(d db.DB, cors bool) App {
+	app := App{
+		d:        d,
+		handlers: make(map[string]http.HandlerFunc),
+	}
+	techHandler := app.GetTechnologies
+	if !cors {
+		techHandler = disableCors(techHandler)
+	}
+	app.handlers["/api/technologies"] = techHandler
+	app.handlers["/"] = http.FileServer(http.Dir("/webapp")).ServeHTTP
+	return app
+}
+
+func (a *App) Serve() error {
+	for path, handler := range a.handlers {
+		http.Handle(path, handler)
+	}
+	log.Println("Web server is available on port 8080")
+	return http.ListenAndServe(":8080", nil)
+}
+
+func (a *App) GetTechnologies(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	technologies, err := a.d.GetTechnologies()
+	if err != nil {
+		sendErr(w, http.StatusInternalServerError, err.Error())
+		return
+	}
+	err = json.NewEncoder(w).Encode(technologies)
+	if err != nil {
+		sendErr(w, http.StatusInternalServerError, err.Error())
+	}
+}
+
+func sendErr(w http.ResponseWriter, code int, message string) {
+	resp, _ := json.Marshal(map[string]string{"error": message})
+	http.Error(w, string(resp), code)
+}
+
+// Needed in order to disable CORS for local development
+func disableCors(h http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Access-Control-Allow-Methods", "*")
+		w.Header().Set("Access-Control-Allow-Headers", "*")
+		h(w, r)
+	}
+}

simple-blog/server/web/app_test.go

@@ -0,0 +1,57 @@
+package web
+
+import (
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"simple-blog/model"
+	"testing"
+)
+
+type MockDb struct {
+	tech []*model.Technology
+	err  error
+}
+
+func (m *MockDb) GetTechnologies() ([]*model.Technology, error) {
+	return m.tech, m.err
+}
+
+func TestApp_GetTechnologies(t *testing.T) {
+	app := App{d: &MockDb{
+		tech: []*model.Technology{
+			{"Tech1", "Details1"},
+			{"Tech2", "Details2"},
+		},
+	}}
+
+	r, _ := http.NewRequest("GET", "/api/technologies", nil)
+	w := httptest.NewRecorder()
+
+	app.GetTechnologies(w, r)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("handler returned wrong status code: got %v want %v", w.Code, http.StatusOK)
+	}
+
+	want := `[{"name":"Tech1","details":"Details1"},{"name":"Tech2","details":"Details2"}]` + "\n"
+	if got := w.Body.String(); got != want {
+		t.Errorf("handler returned unexpected body: got %v want %v", got, want)
+	}
+}
+
+func TestApp_GetTechnologies_WithDBError(t *testing.T) {
+	app := App{d: &MockDb{
+		tech: nil,
+		err:  errors.New("unknown error"),
+	}}
+
+	r, _ := http.NewRequest("GET", "/api/technologies", nil)
+	w := httptest.NewRecorder()
+
+	app.GetTechnologies(w, r)
+
+	if w.Code != http.StatusInternalServerError {
+		t.Errorf("handler returned wrong status code: got %v want %v", w.Code, http.StatusOK)
+	}
+}