Homework final 2

lesson_5/.gitignore

@@ -0,0 +1 @@
+.idea

lesson_5/cmd/go.mod

@@ -0,0 +1,3 @@
+module main.go
+
+go 1.16

lesson_5/cmd/main.go

@@ -0,0 +1,93 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"math"
+)
+
+type Shape interface {
+	Area() (float64, error)
+	Perimeter() (float64, error)
+}
+
+type Circle struct {
+	radius float64
+}
+
+type Rectangle struct {
+	height float64
+	width  float64
+}
+
+func (c Circle) String() string {
+	return fmt.Sprintf("Circle: radius=%.2f", c.radius)
+}
+
+func (r Rectangle) String() string {
+	return fmt.Sprintf("Rectangle: width=%.2f height=%.2f", r.width, r.height)
+}
+
+func (c Circle) Area() (float64, error) {
+	if c.radius <= 0 {
+		return 0, errors.New("Negative radius\n")
+	} else {
+		return math.Pi * c.radius * c.radius, nil
+	}
+}
+
+func (c Circle) Perimeter() (float64, error) {
+	if c.radius <= 0 {
+		return 0, errors.New("Negative radius\n")
+	} else {
+		return 2 * math.Pi * c.radius, nil
+	}
+
+}
+
+func (r Rectangle) Area() (float64, error) {
+	if r.width <= 0 {
+		return 0, errors.New("Negative width\n")
+	} else if r.height <= 0 {
+		return 0, errors.New("Negative height\n")
+	} else {
+		return r.width * r.height, nil
+	}
+}
+
+func (r Rectangle) Perimeter() (float64, error) {
+	if r.width <= 0 {
+		return 0, errors.New("Negative width\n")
+	} else if r.height <= 0 {
+		return 0, errors.New("Negative height\n")
+	} else {
+		return (r.width + r.height) * 2, nil
+	}
+}
+
+func DescribeShape(s Shape) {
+	fmt.Println(s)
+	resArea, err := s.Area()
+	if err == nil {
+		fmt.Println(err)
+	} else {
+		fmt.Printf("Area: %.2f\n", resArea)
+	}
+
+	resPerimeter, err := s.Perimeter()
+	if err != nil {
+		fmt.Println(err)
+	} else {
+		fmt.Printf("Perimeter: %.2f\n", resPerimeter)
+	}
+
+}
+func main() {
+	c := Circle{radius: 8}
+	r := Rectangle{
+		height: 9,
+		width:  3,
+	}
+	DescribeShape(c)
+	DescribeShape(r)
+}

lesson_5/cmd/main_test.go

@@ -0,0 +1,177 @@
+package main
+
+import "testing"
+
+func TestCircle_Area(t *testing.T) {
+	type fields struct {
+		radius float64
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		want    float64
+		wantErr bool
+	}{
+		{name: "return err if negative value",
+			fields:  fields{radius: -10},
+			want:    0,
+			wantErr: true,
+		},
+		{name: "return 201.06192982974676",
+			fields:  fields{radius: 8},
+			want:    201.06192982974676,
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c := Circle{
+				radius: tt.fields.radius,
+			}
+			got, err := c.Area()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Area() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("Area() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestCircle_Perimeter(t *testing.T) {
+	type fields struct {
+		radius float64
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		want    float64
+		wantErr bool
+	}{
+		{
+			name:    "negative value",
+			fields:  fields{radius: -10},
+			want:    0,
+			wantErr: true,
+		},
+		{
+			name:    "want to 50.26548245743669 value",
+			fields:  fields{radius: 8},
+			want:    50.26548245743669,
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c := Circle{
+				radius: tt.fields.radius,
+			}
+			got, err := c.Perimeter()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Perimeter() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("Perimeter() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestRectangle_Area(t *testing.T) {
+	type fields struct {
+		height float64
+		width  float64
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		want    float64
+		wantErr bool
+	}{
+		{
+			name:    "want to 27.0 value",
+			fields:  fields{width: 3, height: 9},
+			want:    27.0,
+			wantErr: false,
+		},
+		{
+			name:    "err negative width",
+			fields:  fields{width: -3, height: 9},
+			want:    0,
+			wantErr: true,
+		},
+		{
+			name:    "err negative height",
+			fields:  fields{width: 3, height: -9},
+			want:    0,
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			r := Rectangle{
+				height: tt.fields.height,
+				width:  tt.fields.width,
+			}
+			got, err := r.Area()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Area() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("Area() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestRectangle_Perimeter(t *testing.T) {
+	type fields struct {
+		height float64
+		width  float64
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		want    float64
+		wantErr bool
+	}{
+		{
+			name:    "want to 27 value",
+			fields:  fields{width: 3, height: 9},
+			want:    24,
+			wantErr: false,
+		},
+		{
+			name:    "err negative width",
+			fields:  fields{width: -3, height: 9},
+			want:    0,
+			wantErr: true,
+		},
+		{
+			name:    "err negative height",
+			fields:  fields{width: 3, height: -9},
+			want:    0,
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			r := Rectangle{
+				height: tt.fields.height,
+				width:  tt.fields.width,
+			}
+			got, err := r.Perimeter()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Perimeter() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("Perimeter() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

lesson_6/.gitignore

@@ -0,0 +1 @@
+.idea

lesson_6/task_1/go.mod

@@ -0,0 +1,3 @@
+module main.go
+
+go 1.16

lesson_6/task_1/main.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+)
+
+type User struct {
+	Host       string              `json:"host: "`
+	UserAgent  string              `json:"user_agent: "`
+	RequestUri string              `json:"request_uri: "`
+	Headers    map[string][]string `json:"headers: "`
+}
+
+func (u User) String() string {
+	j, _ := json.MarshalIndent(u, "", "  ")
+	return string(j)
+}
+
+func currentUser(r *http.Request) User {
+	var u User
+	u.Headers = make(map[string][]string)
+	u.Host = r.Host
+	u.UserAgent = r.UserAgent()
+	u.RequestUri = r.RequestURI
+	u.Headers["Accept"] = r.Header["Accept"]
+	u.Headers["User-Agent"] = r.Header["User-Agent"]
+
+	return u
+}
+
+func root(w http.ResponseWriter, r *http.Request) {
+	u := currentUser(r)
+	fmt.Fprintf(w, u.String())
+}
+
+func main() {
+	fmt.Println("Start to port 8080...")
+	http.HandleFunc("/", root)
+	if err := http.ListenAndServe(":8080", nil); err != nil {
+		log.Fatal(err)
+	}
+}

lesson_6/task_2/client.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"os"
+)
+
+func main() {
+	conn, _ := net.Dial("tcp", "127.0.0.1:8080")
+	defer conn.Close()
+	for {
+		reader := bufio.NewReader(os.Stdin)
+		fmt.Print("Text to send: ")
+		text, _ := reader.ReadString('\n')
+		fmt.Fprintf(conn, text)
+		message, _ := bufio.NewReader(conn).ReadString('\n')
+		fmt.Print("Message from server: " + message)
+
+		r := []rune(message)
+		r = r[:len(r)-2]
+		text = string(r)
+		if text == "EXIT" {
+			break
+		}
+	}
+}

lesson_6/task_2/server.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+)
+
+func main() {
+
+	fmt.Println("Launching server...")
+	ln, _ := net.Listen("tcp", ":8080")
+	conn, _ := ln.Accept()
+
+	for {
+		message, _ := bufio.NewReader(conn).ReadString('\n')
+		fmt.Print("Message Received:", message)
+		r := []rune(message)
+		r = r[:len(r)-2]
+
+		var newMessage string
+		i, err := strconv.Atoi(string(r))
+		if err == nil {
+			newMessage = strconv.Itoa(i * 2)
+		} else {
+			newMessage = strings.ToUpper(message)
+		}
+		conn.Write([]byte(newMessage + "\n"))
+	}
+}