HW09 is completed

hw09_generator_of_validators/go-validate/generate.go

@@ -0,0 +1,115 @@
+package main
+
+import (
+	"bytes"
+	"go/format"
+	"text/template"
+)
+
+var goValidateTemplate = template.Must(template.New("go-validate").Parse(`
+// generated by go-validate; DO NOT EDIT
+package models
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type ValidationError struct {
+	Field string
+	Err   error
+}
+
+func ContainsInt(toFind int, searchingString string) bool {
+	for _, strValue := range strings.Split(searchingString, ",") {
+		invValue, err := strconv.Atoi(strValue)
+		if err != nil {
+			return false
+		}
+		if toFind == invValue {
+			return true
+		}
+	}
+	return false
+}
+
+func ContainsStr(toFind string, searchingString string) bool {
+	for _, value := range strings.Split(searchingString, ",") {
+		if toFind == value {
+			return true
+		}
+	}
+	return false
+}
+
+{{range $index, $struct := .}}
+{{if $struct.Fields}}
+func (structName {{$struct.Name}}) Validate() ([]ValidationError, error) {
+	errors := make([]ValidationError, 0)
+
+	{{range $index, $field := $struct.Fields}}
+
+		{{/* begin loop for slices */}}
+		{{$variableName := $field.Name | printf "%s.%s" "structName"}}
+		{{if $field.IsSlice}}
+			for _, value := range structName.{{$field.Name}} {
+			{{$variableName = "value"}}			
+		{{end}}
+
+		{{range $index, $condition := $field.Conditions}}
+			{{if eq $condition.Name "len"}}
+				if len({{$variableName}}) != {{$condition.Value}} {
+					errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} length")})
+				}
+			{{else if eq $condition.Name "min"}}
+				if {{$variableName}} < {{$condition.Value}} {
+					errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} length")})
+				}
+			{{else if eq $condition.Name "max"}}
+				if {{$variableName}} > {{$condition.Value}} {
+					errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} length")})
+				}
+			{{else if eq $condition.Name "regexp"}}
+				if re := regexp.MustCompile({{$condition.Value | printf "%q"}}); re.FindString({{$field.Type}}({{$variableName}})) == "" {
+					errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} field, empty regexp")})
+				}
+			{{else if eq $condition.Name "in"}}
+				{{if eq $field.Type "int"}}
+					if !ContainsInt({{$field.Type}}({{$variableName}}), "{{$condition.Value}}") {
+						errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} value in range")})
+					}
+				{{else if eq $field.Type "string"}}
+					if !ContainsStr({{$field.Type}}({{$variableName}}), "{{$condition.Value}}") {
+						errors = append(errors, ValidationError{Field: "{{$field.Name}}", Err: fmt.Errorf("invalid {{$field.Name}} value in range")})
+					}
+				{{end}}
+			{{end}}
+		{{end}}
+
+		{{/* end loop for slices */}}
+		{{if $field.IsSlice}}
+			}
+		{{end}}
+	{{end}}
+	return errors, nil
+}
+{{end}}
+{{end}}
+`))
+
+func GenerateDocument(recvStruct []ParsedStruct) ([]byte, error) {
+	var buf bytes.Buffer
+	err := goValidateTemplate.Execute(&buf, recvStruct)
+	if err != nil {
+		return nil, err
+	}
+
+	document, err := format.Source(buf.Bytes())
+	if err != nil {
+		return nil, err
+	}
+
+	return document, nil
+}

hw09_generator_of_validators/go-validate/generate_test.go

@@ -0,0 +1,103 @@
+package main
+
+import (
+	"io/ioutil"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGenerate(t *testing.T) {
+	t.Run("generate document and compare with file", func(t *testing.T) {
+		defaultStruct := []ParsedStruct{
+			ParsedStruct{
+				Name: "User",
+				Fields: []Field{
+					Field{
+						Name:    "ID",
+						Type:    "string",
+						IsSlice: false,
+						Conditions: []Condition{
+							Condition{
+								Name:  "len",
+								Value: "36",
+							},
+						},
+					},
+					Field{
+						Name:    "Age",
+						Type:    "int",
+						IsSlice: false,
+						Conditions: []Condition{
+							Condition{
+								Name:  "min",
+								Value: "18",
+							},
+							Condition{
+								Name:  "max",
+								Value: "50",
+							},
+						},
+					},
+					Field{
+						Name:    "Email",
+						Type:    "string",
+						IsSlice: false,
+						Conditions: []Condition{
+							Condition{
+								Name:  "regexp",
+								Value: "^\\w+@\\w+\\.\\w+$",
+							},
+						},
+					},
+					Field{
+						Name:    "Role",
+						Type:    "UserRole",
+						IsSlice: false,
+						Conditions: []Condition{
+							Condition{
+								Name:  "in",
+								Value: "admin,stuff",
+							},
+						},
+					},
+					Field{
+						Name:    "Phones",
+						Type:    "string",
+						IsSlice: true,
+						Conditions: []Condition{
+							Condition{
+								Name:  "len",
+								Value: "11",
+							},
+						},
+					},
+				},
+			},
+			ParsedStruct{
+				Name: "App",
+				Fields: []Field{
+					Field{
+						Name:    "Version",
+						Type:    "string",
+						IsSlice: false,
+						Conditions: []Condition{
+							Condition{
+								Name:  "len",
+								Value: "5",
+							},
+						},
+					},
+				},
+			},
+		}
+
+		document, err := GenerateDocument(defaultStruct)
+		require.Nil(t, err)
+
+		fileBytes, err := ioutil.ReadFile("testdata/test_models_validation_generated.go")
+		require.Nil(t, err)
+
+		require.Equal(t, fileBytes, document)
+	})
+}

hw09_generator_of_validators/go-validate/main.go

@@ -1,5 +1,66 @@
 package main
 
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+type ParsedDocument struct {
+	Structs []ParsedStruct
+	Aliases AliasedStructs
+}
+
+type ParsedStruct struct {
+	Name   string
+	Fields []Field
+}
+
+type Field struct {
+	Name       string
+	Type       string
+	IsSlice    bool
+	Conditions []Condition
+}
+
+type Condition struct {
+	Name  string
+	Value string
+}
+
+type AliasedStructs map[string]string
+
 func main() {
-	// Place your code here
+	if len(os.Args) < 2 {
+		fmt.Println("Usage: go-validate [module path]")
+		os.Exit(1)
+	}
+
+	filename := os.Args[1]
+	parsedStruct, err := ParseStruct(filename)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	validatedStruct := ValidateStruct(parsedStruct)
+	document, err := GenerateDocument(validatedStruct)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	savedFilename := strings.TrimSuffix(filename, ".go")
+	f, err := os.Create(fmt.Sprintf("%s_validation_generated.go", savedFilename))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	defer f.Close()
+
+	_, err = f.Write(document)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
 }