chore: init repository

internal/storage/dao/database_error.go

@@ -0,0 +1,32 @@
+package dao
+
+import (
+	"fmt"
+)
+
+type Type int
+
+const (
+	ErrTypeNotFound Type = iota
+	ErrTypeDuplicate
+	ErrTypeForeignKeyViolation
+)
+
+type Error struct {
+	Cause error
+	Type  Type
+}
+
+func NewDAOError(t Type, cause error) error {
+	return &Error{
+		Type:  t,
+		Cause: cause,
+	}
+}
+
+func (e *Error) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("Type %d: %s", e.Type, e.Cause.Error())
+	}
+	return fmt.Sprintf("Type %d: no cause given", e.Type)
+}

internal/storage/dao/postgresql/database_postgresql.go

@@ -0,0 +1,43 @@
+package postgresql
+
+import (
+	"database/sql"
+	"fmt"
+	"john/internal/storage/dao"
+	"john/internal/utils"
+
+	"github.com/lib/pq"
+)
+
+const (
+	pgCodeUniqueViolation     = "23505"
+	pgCodeForeingKeyViolation = "23503"
+)
+
+func HandlePgError(e *pq.Error) error {
+	if e.Code == pgCodeUniqueViolation {
+		return dao.NewDAOError(dao.ErrTypeDuplicate, e)
+	}
+
+	if e.Code == pgCodeForeingKeyViolation {
+		return dao.NewDAOError(dao.ErrTypeForeignKeyViolation, e)
+	}
+	return e
+}
+
+type DatabasePostgreSQL struct {
+	Session *sql.DB
+}
+
+func NewDatabasePostgreSQL(connectionURI string) *DatabasePostgreSQL {
+	db, err := sql.Open("postgres", connectionURI)
+	if err != nil {
+		utils.GetLogger().WithError(err).Fatal("Unable to get a connection to the postgres db")
+	}
+	err = db.Ping()
+	if err != nil {
+		fmt.Println(err)
+		utils.GetLogger().WithError(err).Fatal("Unable to ping the postgres db")
+	}
+	return &DatabasePostgreSQL{Session: db}
+}

internal/storage/model/error.go

@@ -0,0 +1,68 @@
+package model
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/lib/pq"
+)
+
+var (
+	// 400
+	ErrBadRequestFormat = APIError{
+		Type:        "bad_format",
+		HTTPCode:    http.StatusBadRequest,
+		Description: "unable to read request body, please check that the json is valid",
+	}
+	ErrDataValidation = APIError{
+		Type:        "data_validation",
+		HTTPCode:    http.StatusBadRequest,
+		Description: "the data are not valid",
+	}
+
+	// 404
+	ErrNotFound = APIError{
+		Type:     "not_found",
+		HTTPCode: http.StatusNotFound,
+	}
+
+	// 40x
+	ErrAlreadyExists = APIError{
+		Type:     "already_exists",
+		HTTPCode: http.StatusConflict,
+	}
+
+	// 50x
+	ErrInternalServer = APIError{
+		Type:     "internal_server_error",
+		HTTPCode: http.StatusInternalServerError,
+	}
+)
+
+type APIError struct {
+	HTTPCode    int                 `json:"-"`
+	Type        string              `json:"error"`
+	Description string              `json:"error_description"`
+	Details     []FieldError        `json:"error_details,omitempty"`
+	Headers     map[string][]string `json:"-"`
+}
+
+type FieldError struct {
+	Field       string `json:"field"`
+	Constraint  string `json:"constraint"`
+	Description string `json:"description"`
+}
+
+func (e *APIError) Error() string {
+	return fmt.Sprintf("error : %d, %s, %s, %v", e.HTTPCode, e.Type, e.Description, e.Details)
+}
+
+func FromPostgresError(err *pq.Error) *APIError {
+	return &APIError{
+		HTTPCode:    0,
+		Type:        "",
+		Description: "",
+		Details:     nil,
+		Headers:     nil,
+	}
+}

internal/storage/validators/error.go

@@ -0,0 +1,43 @@
+package validators
+
+import (
+	"fmt"
+	"gopkg.in/go-playground/validator.v9"
+	"john/internal/storage/model"
+	"john/internal/utils"
+	"regexp"
+	"strings"
+)
+
+var regexpValidatorNamespacePrefix = regexp.MustCompile(`^\w+\.`)
+
+func NewDataValidationAPIError(err error) model.APIError {
+	apiErr := model.ErrDataValidation
+	if err != nil {
+		if _, ok := err.(*validator.InvalidValidationError); ok {
+			utils.GetLogger().WithError(err).WithField("templateAPIErr", apiErr).Error("InvalidValidationError")
+		} else {
+			for _, e := range err.(validator.ValidationErrors) {
+				reason := e.Tag()
+				if _, ok := CustomValidators[e.Tag()]; ok {
+					reason = truncatingSprintf(CustomValidators[e.Tag()].Message, e.Param())
+				}
+
+				namespaceWithoutStructName := regexpValidatorNamespacePrefix.ReplaceAllString(e.Namespace(), "")
+				fe := model.FieldError{
+					Field:       namespaceWithoutStructName,
+					Constraint:  e.Tag(),
+					Description: reason,
+				}
+				apiErr.Details = append(apiErr.Details, fe)
+			}
+		}
+	}
+	return apiErr
+}
+
+// truncatingSprintf is used as fmt.Sprintf but allow to truncate the additional parameters given when there is more parameters than %v in str
+func truncatingSprintf(str string, args ...interface{}) string {
+	n := strings.Count(str, "%v")
+	return fmt.Sprintf(str, args[:n]...)
+}

internal/storage/validators/validators.go

@@ -0,0 +1,34 @@
+package validators
+
+import (
+	"context"
+	"strings"
+
+	"gopkg.in/go-playground/validator.v9"
+)
+
+var (
+	CustomValidators = map[string]customValidator{
+		"enum": {
+			Message:   "This field should be in: %v",
+			Validator: validateEnum,
+		},
+		"required": {
+			Message: "This field is required and cannot be empty",
+		},
+	}
+)
+
+type customValidator struct {
+	Message   string
+	Validator validator.FuncCtx
+}
+
+func validateEnum(ctx context.Context, fl validator.FieldLevel) bool {
+	for _, v := range strings.Split(fl.Param(), " ") {
+		if v == fl.Field().String() {
+			return true
+		}
+	}
+	return false
+}

internal/user/database.go

@@ -0,0 +1,113 @@
+package user
+
+import (
+	"database/sql"
+	"john/internal/storage/dao"
+	"john/internal/storage/dao/postgresql"
+
+	"github.com/lib/pq"
+)
+
+type Database struct {
+	*postgresql.DatabasePostgreSQL
+}
+
+func NewDatabase(db *postgresql.DatabasePostgreSQL) *Database {
+	return &Database{db}
+}
+
+func (db *Database) GetAllUsers() ([]*User, error) {
+	q := `
+		SELECT u.id, u.created_at, u.updated_at, u.email
+		FROM public.user u
+	`
+	rows, err := db.Session.Query(q)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	us := make([]*User, 0)
+	for rows.Next() {
+		u := User{}
+		err := rows.Scan(&u.ID, &u.CreatedAt, &u.UpdatedAt, &u.Email)
+		if err != nil {
+			return nil, err
+		}
+		us = append(us, &u)
+	}
+	return us, nil
+}
+
+func (db *Database) GetUsersByID(id string) (*User, error) {
+	q := `
+		SELECT u.id, u.created_at, u.updated_at, u.email
+		FROM public.user u
+		WHERE u.id = $1
+	`
+	row := db.Session.QueryRow(q, id)
+
+	u := User{}
+	err := row.Scan(&u.ID, &u.CreatedAt, &u.UpdatedAt, &u.Email)
+	if errPq, ok := err.(*pq.Error); ok {
+		return nil, postgresql.HandlePgError(errPq)
+	}
+	if err == sql.ErrNoRows {
+		return nil, dao.NewDAOError(dao.ErrTypeNotFound, err)
+	}
+	return &u, err
+}
+
+func (db *Database) CreateUser(user *User) error {
+	q := `
+		INSERT INTO public.user
+			(email, google_id)
+		VALUES
+			($1, $2)
+		RETURNING id, created_at
+	`
+
+	err := db.Session.
+		QueryRow(q, user.Email, user.GoogleID).
+		Scan(&user.ID, &user.CreatedAt)
+	if errPq, ok := err.(*pq.Error); ok {
+		return postgresql.HandlePgError(errPq)
+	}
+	return err
+}
+
+func (db *Database) DeleteUser(id string) error {
+	q := `
+		DELETE FROM public.user
+		WHERE id = $1
+	`
+
+	_, err := db.Session.Exec(q, id)
+	if errPq, ok := err.(*pq.Error); ok {
+		return postgresql.HandlePgError(errPq)
+	}
+	return err
+}
+
+func (db *Database) UpdateUser(user *User) error {
+	return nil
+}
+
+func (db *Database) GetUsersByGoogleID(id string) (*User, error) {
+	q := `
+		SELECT u.id, u.created_at, u.updated_at, u.email, u.google_id
+		FROM public.user u
+		WHERE u.google_id = $1
+	`
+	row := db.Session.QueryRow(q, id)
+
+	u := User{}
+	err := row.Scan(&u.ID, &u.CreatedAt, &u.UpdatedAt, &u.Email, &u.GoogleID)
+	if errPq, ok := err.(*pq.Error); ok {
+		return nil, postgresql.HandlePgError(errPq)
+	}
+	if err == sql.ErrNoRows {
+		return nil, dao.NewDAOError(dao.ErrTypeNotFound, err)
+	}
+	return &u, err
+}

internal/user/handler.go

@@ -0,0 +1,133 @@
+package user
+
+import (
+	"john/handler"
+	"john/internal/storage/dao/postgresql"
+	"john/internal/storage/model"
+	"john/internal/utils"
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+
+	"google.golang.org/api/oauth2/v2"
+)
+
+type Context struct {
+	service *Service
+	db      *Database
+	*handler.Context
+}
+
+func NewHandler(ctx *handler.Context, db *postgresql.DatabasePostgreSQL) *Context {
+	database := NewDatabase(db)
+	service := NewService(database)
+	return &Context{service: service, db: database, Context: ctx}
+}
+
+func (uc *Context) GetAllUsers(c *gin.Context) {
+	users, err := uc.db.GetAllUsers()
+	if err != nil {
+		utils.GetLoggerFromCtx(c).WithError(err).Error("error while getting users")
+		utils.JSONErrorWithMessage(c.Writer, model.ErrInternalServer, "Error while getting users")
+		return
+	}
+	utils.JSON(c.Writer, http.StatusOK, users)
+}
+
+func (hc *Context) ConnectUser(c *gin.Context) {
+	authorizationHeader := c.GetHeader("Authorization")
+	authorizationHeaderSplitted := strings.Split(authorizationHeader, " ")
+	if len(authorizationHeaderSplitted) != 2 {
+		utils.JSONError(c.Writer, model.ErrBadRequestFormat)
+		return
+	}
+
+	oauth2Service, err := oauth2.New(&http.Client{})
+	if oauth2Service == nil {
+		utils.GetLoggerFromCtx(c).WithError(err).Error(err)
+		utils.JSONError(c.Writer, model.ErrInternalServer)
+		return
+	}
+	tokenInfoCall := oauth2Service.Tokeninfo()
+	tokenInfoCall.IdToken(authorizationHeaderSplitted[1])
+	tokenInfo, err := tokenInfoCall.Do()
+	if err != nil {
+		utils.GetLoggerFromCtx(c).WithError(err).Error(err)
+		utils.JSONError(c.Writer, model.ErrBadRequestFormat)
+		return
+	}
+	user, err := hc.service.GetUserFromGoogleID(tokenInfo.UserId)
+	if err != nil {
+		if castedError, ok := err.(*model.APIError); ok {
+			if castedError.Type == model.ErrNotFound.Type {
+				user, err := hc.service.CreateUserFromGoogleToken(tokenInfo.UserId, tokenInfo.Email)
+				if err != nil {
+					utils.GetLoggerFromCtx(c).WithError(err).Error(err)
+					utils.JSONError(c.Writer, model.ErrInternalServer)
+					return
+				}
+				utils.JSON(c.Writer, 200, user)
+				return
+			}
+			utils.JSONError(c.Writer, *castedError)
+			return
+		}
+		utils.GetLoggerFromCtx(c).WithError(err).Error(err)
+		utils.JSONError(c.Writer, model.ErrInternalServer)
+		return
+	}
+	utils.JSON(c.Writer, 200, user)
+}
+
+func (hc *Context) CreateUser(c *gin.Context) {
+	authorizationHeader := c.GetHeader("Authorization")
+	authorizationHeaderSplitted := strings.Split(authorizationHeader, " ")
+	if len(authorizationHeaderSplitted) != 2 {
+		utils.JSONError(c.Writer, model.ErrBadRequestFormat)
+		return
+	}
+
+	oauth2Service, err := oauth2.New(&http.Client{})
+	if oauth2Service == nil {
+		utils.GetLogger().WithError(err).Error(err)
+		utils.JSONError(c.Writer, model.ErrInternalServer)
+		return
+	}
+	tokenInfoCall := oauth2Service.Tokeninfo()
+	tokenInfoCall.IdToken(authorizationHeaderSplitted[1])
+	tokenInfo, err := tokenInfoCall.Do()
+	if err != nil {
+		utils.GetLogger().WithError(err).Error(err)
+		utils.JSONError(c.Writer, model.ErrBadRequestFormat)
+		return
+	}
+	user, err := hc.service.GetUserFromGoogleID(tokenInfo.UserId)
+	if err != nil {
+		utils.GetLogger().WithError(err).Error(err)
+		if castedError, ok := err.(*model.APIError); ok {
+			if castedError.Type == model.ErrNotFound.Type {
+				user, err := hc.service.CreateUserFromGoogleToken(tokenInfo.UserId, tokenInfo.Email)
+				if err != nil {
+					utils.GetLogger().WithError(err).Error(err)
+					utils.JSONError(c.Writer, model.ErrInternalServer)
+					return
+				}
+				utils.JSON(c.Writer, http.StatusCreated, user)
+				return
+			}
+			utils.JSONError(c.Writer, *castedError)
+			return
+		}
+		utils.GetLogger().Info(err)
+		utils.JSONError(c.Writer, model.ErrInternalServer)
+		return
+	}
+	utils.JSON(c.Writer, http.StatusOK, user)
+}
+
+func (hc *Context) GetUser(c *gin.Context) {
+	userID := c.Param("userId")
+	user, _ := hc.service.GetUserById(userID)
+	utils.JSON(c.Writer, http.StatusOK, user)
+}

internal/user/model.go

@@ -0,0 +1,17 @@
+package user
+
+import (
+	"time"
+)
+
+type User struct {
+	UserEditable
+	ID        string     `json:"id"`
+	CreatedAt time.Time  `json:"createdAt"`
+	UpdatedAt *time.Time `json:"updatedAt"`
+	GoogleID  string     `json:"-"`
+}
+
+type UserEditable struct {
+	Email string `json:"email" validate:"required"`
+}

internal/user/service.go

@@ -0,0 +1,55 @@
+package user
+
+import (
+	"john/internal/storage/dao"
+	"john/internal/storage/model"
+)
+
+type Service struct {
+	db *Database
+}
+
+func NewService(database *Database) *Service {
+	return &Service{db: database}
+}
+
+func (s *Service) GetUserById(userId string) (*User, error) {
+	user, err := s.db.GetUsersByID(userId)
+	if e, ok := err.(*dao.Error); ok {
+		switch {
+		case e.Type == dao.ErrTypeNotFound:
+			return nil, &model.ErrNotFound
+		default:
+			return nil, &model.ErrInternalServer
+		}
+	} else if err != nil {
+		return nil, &model.ErrInternalServer
+	}
+
+	if user == nil {
+		return nil, &model.ErrNotFound
+	}
+	return user, nil
+}
+
+func (us *Service) GetUserFromGoogleID(googleUserID string) (*User, error) {
+	user, err := us.db.GetUsersByGoogleID(googleUserID)
+	if err != nil {
+		if castedError, ok := err.(*dao.Error); ok {
+			switch castedError.Type {
+			case dao.ErrTypeNotFound:
+				return nil, &model.ErrNotFound
+			default:
+				return nil, &model.ErrInternalServer
+			}
+		}
+		return nil, &model.ErrInternalServer
+	}
+	return user, nil
+}
+
+func (us *Service) CreateUserFromGoogleToken(id string, email string) (*User, error) {
+	user := &User{UserEditable: UserEditable{Email: email}, GoogleID: id}
+	err := us.db.CreateUser(user)
+	return user, err
+}

internal/utils/headers.go

@@ -0,0 +1,8 @@
+package utils
+
+const (
+	HeaderNameContentType   = "content-type"
+	HeaderNameCorrelationID = "correlationID"
+
+	HeaderValueApplicationJSONUTF8 = "application/json; charset=UTF-8"
+)

internal/utils/logger.go

@@ -0,0 +1,74 @@
+package utils
+
+import (
+	"io"
+	"os"
+
+	"github.com/gin-gonic/gin"
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	LogFormatText = "text"
+	LogFormatJSON = "json"
+
+	ContextKeyLogger = "logger"
+)
+
+var (
+	logLevel                   = logrus.DebugLevel
+	logFormat logrus.Formatter = &logrus.TextFormatter{}
+	logOut    io.Writer
+)
+
+func InitLogger(ll, lf string) {
+	logLevel = parseLogrusLevel(ll)
+	logrus.SetLevel(logLevel)
+
+	logFormat = parseLogrusFormat(lf)
+	logrus.SetFormatter(logFormat)
+
+	logOut = os.Stdout
+	logrus.SetOutput(logOut)
+}
+
+func GetLoggerFromCtx(c *gin.Context) *logrus.Entry {
+	if logger, ok := c.Get(ContextKeyLogger); ok {
+		logEntry, assertionOk := logger.(*logrus.Entry)
+		if assertionOk {
+			return logEntry
+		}
+	}
+	return logrus.NewEntry(GetLogger())
+}
+
+func GetLogger() *logrus.Logger {
+	logger := logrus.New()
+	logger.Formatter = logFormat
+	logger.Level = logLevel
+	logger.Out = logOut
+	return logger
+}
+
+func parseLogrusLevel(logLevelStr string) logrus.Level {
+	logLevel, err := logrus.ParseLevel(logLevelStr)
+	if err != nil {
+		logrus.WithError(err).Errorf("error while parsing log level. %v is set as default.", logLevel)
+		logLevel = logrus.DebugLevel
+	}
+	return logLevel
+}
+
+func parseLogrusFormat(logFormatStr string) logrus.Formatter {
+	var formatter logrus.Formatter
+	switch logFormatStr {
+	case LogFormatText:
+		formatter = &logrus.TextFormatter{ForceColors: true, FullTimestamp: true}
+	case LogFormatJSON:
+		formatter = &logrus.JSONFormatter{}
+	default:
+		logrus.Errorf("error while parsing log format. %v is set as default.", formatter)
+		formatter = &logrus.TextFormatter{ForceColors: true, FullTimestamp: true}
+	}
+	return formatter
+}

internal/utils/randomizer/rand.go

@@ -0,0 +1,45 @@
+package randomizer
+
+import (
+	"fmt"
+	"math/rand"
+)
+
+type Random interface {
+	Int() int
+}
+
+func init() {}
+
+type rndGenerator func(n int) int
+
+type Randomizer struct {
+	fn rndGenerator
+}
+
+func NewRandomizer(fn rndGenerator) *Randomizer {
+	return &Randomizer{fn: fn}
+}
+
+func (r *Randomizer) Int(n int) int {
+	return r.fn(n)
+}
+
+func Rand(rand int) int {
+	return randGen(rand)
+}
+func realRand(n int) int { return int(rand.Intn(n)) }
+func fakeRand(n int) func(numb int) int {
+	return func(numb int) int {
+		if n >= numb {
+			panic(fmt.Sprintf("%d Should not be superior of %d", n, numb))
+		}
+		return n
+	}
+}
+
+var randGen = NewRandomizer(realRand).Int
+
+func FakeRandomizer(n int) {
+	randGen = NewRandomizer(fakeRand(n)).Int
+}

internal/utils/responses.go

@@ -0,0 +1,31 @@
+package utils
+
+import (
+	"encoding/json"
+	"john/internal/storage/model"
+	"net/http"
+)
+
+func JSON(w http.ResponseWriter, status int, data interface{}) {
+	w.Header().Set(HeaderNameContentType, HeaderValueApplicationJSONUTF8)
+	w.WriteHeader(status)
+	if data != nil {
+		json.NewEncoder(w).Encode(data)
+	}
+}
+
+func JSONError(w http.ResponseWriter, e model.APIError) {
+	if e.Headers != nil {
+		for k, headers := range e.Headers {
+			for _, headerValue := range headers {
+				w.Header().Add(k, headerValue)
+			}
+		}
+	}
+	JSON(w, e.HTTPCode, e)
+}
+
+func JSONErrorWithMessage(w http.ResponseWriter, e model.APIError, message string) {
+	e.Description = message
+	JSONError(w, e)
+}