Added review comments

api.go

@@ -5,15 +5,24 @@ import (
 	"net/http"
 )
 
+// Don't add all functionalities into a single function.
+// Follow the single Responsibility rule.
+// This also helps in writing the test functions easily.
+// Move the code to a seperate package called handlers instead of defining them in main package
 func setupJsonApi() {
+	// The Handlers can be moved to a seperate package
 	http.HandleFunc("/createUser", func(w http.ResponseWriter, r *http.Request) {
 		// create mysql connection
+		// Instead of creating a connection everytime, Create it once and store it in a structure so the same connection can be accessed whenever needed
 		conn := createConnection()
 		name := r.FormValue("name")
 		email := r.FormValue("email")
+		// Passing the Query in this format can cause SQL Injections, You can avoid this by using parameterized queries.
 		query := "INSERT INTO users (name, email) VALUES (" + name + ", " + email + ")"
 		result, err := conn.Exec(query)
+		// Again, Error shouldn't be handled like this as mentioned in utils.go
 		fmt.Println("result ", result, " err ", err.Error())
+		// Use Proper http status codes and set the http headers properly
 		w.Write([]byte("Created user successfully!"))
 	})
 	http.HandleFunc("/updateUser", func(w http.ResponseWriter, r *http.Request) {

main.go

@@ -4,7 +4,32 @@ import (
 	"net/http"
 )
 
+// Proper Comments should be added to the code wherever needed, It Improves the readability and the maintainability of the code.
 func main() {
+
+	// Follow the go naming convention
+	// Use small letters when you don't want to access a function or variable outside the package and Captital letter when you want to access it outside the package
+	// All the Acronyms used should be in Capital letters.
+	// Name of the shouldn't be long enough and should tell you precisely what it does.
 	setupJsonApi()
+
+	// Use Middlewares to add additional functionalities.
+	// Add CSRF Protection using a middleware
+	// Use routing packages to handle the routes
+
+	// Use a logger package to debug the code easily,
+	// You can use the standard log library from go or a third party logging package like zap, logrun or Zerolog Which give you        additional features like setting the log level, etc.
+
+	/*
+	 Do not hard code values.
+	 Hard coding values can make the code less flexible and requires changes in code if the value needs to be modified in future.
+
+	 Instead of Hard coding values use flag package to pass the value as a command line argument.
+	 Ex. var port = flag.Int("p",8080, "Enter the Port Number on which you want to run the application")
+
+	 You can also use environment variables to get the values
+	 Ex. os.Getenv("APP_PORT") to get the port number
+	*/
 	http.ListenAndServe(":80", nil)
+
 }

utils.go

@@ -7,7 +7,40 @@ import (
 
 // createConnection creates a connection to mysql database
 func createConnection() *sql.DB {
+	// Don't Hard code values as mentioned earlier.
+	// The password shouldn't be hardcoded in the connection string as this is not secure.
+	// Create a structure in go and store all the values required to make the db connection.
+	/*
+		type Database struct {
+			username string,
+			password string,
+			port 	 uint32,
+			addr     string,
+			dbname 	 string,
+			SQLcon	 *sql.DB
+		}
+
+		// Additionally Create a Init function to initialize the structure
+		ex.
+		   func  InitDB(usr, pswd, addr string, port uint32) *Database{} {}
+
+		you can pass this structure as a method receiver to all the methods
+		ex.
+			func(db *Database) CreateConnection() error {}
+
+	*/
 	db, err := sql.Open("mysql", "root:password@tcp(127.0.0.1:3306)/test")
+	// Don't print the errors directly
+	/* Errors in golang are handled like this
+	if err != nil {
+		return fmt.Errorf("DB Connection Error:", err)
+	}
+	*/
 	fmt.Println("sql open " + err.Error())
 	return db
 }
+
+// Use a separate package for database related methods.
+// Don't combile all the functinalties into a single package
+// Add Additional functions to add, update and delete data from a table
+// Close the db connection after using it.