V2 alpha - initial version (#172)

Initial alpha codebase for version 2 of WireGuard Portal.
This version is considered unstable and incomplete (for example, no public REST API)! 
Use with care!


Fixes/Implements the following issues:
 - OAuth support #154, #1 
 - New Web UI with internationalisation support #98, #107, #89, #62
 - Postgres Support #49 
 - Improved Email handling #47, #119 
 - DNS Search Domain support #46 
 - Bugfixes #94, #48 

---------

Co-authored-by: Fabian Wechselberger <wechselbergerf@hotmail.com>

internal/app/auth/auth_oauth.go

@@ -0,0 +1,149 @@
+package auth
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/h44z/wg-portal/internal"
+	"github.com/h44z/wg-portal/internal/config"
+	"github.com/h44z/wg-portal/internal/domain"
+	"golang.org/x/oauth2"
+)
+
+type PlainOauthAuthenticator struct {
+	name                string
+	cfg                 *oauth2.Config
+	userInfoEndpoint    string
+	client              *http.Client
+	userInfoMapping     config.OauthFields
+	registrationEnabled bool
+}
+
+func newPlainOauthAuthenticator(_ context.Context, callbackUrl string, cfg *config.OAuthProvider) (*PlainOauthAuthenticator, error) {
+	var provider = &PlainOauthAuthenticator{}
+
+	provider.name = cfg.ProviderName
+	provider.client = &http.Client{
+		Timeout: time.Second * 10,
+	}
+	provider.cfg = &oauth2.Config{
+		ClientID:     cfg.ClientID,
+		ClientSecret: cfg.ClientSecret,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:   cfg.AuthURL,
+			TokenURL:  cfg.TokenURL,
+			AuthStyle: oauth2.AuthStyleAutoDetect,
+		},
+		RedirectURL: callbackUrl,
+		Scopes:      cfg.Scopes,
+	}
+	provider.userInfoEndpoint = cfg.UserInfoURL
+	provider.userInfoMapping = getOauthFieldMapping(cfg.FieldMap)
+	provider.registrationEnabled = cfg.RegistrationEnabled
+
+	return provider, nil
+}
+
+func (p PlainOauthAuthenticator) GetName() string {
+	return p.name
+}
+
+func (p PlainOauthAuthenticator) RegistrationEnabled() bool {
+	return p.registrationEnabled
+}
+
+func (p PlainOauthAuthenticator) GetType() domain.AuthenticatorType {
+	return domain.AuthenticatorTypeOAuth
+}
+
+func (p PlainOauthAuthenticator) AuthCodeURL(state string, opts ...oauth2.AuthCodeOption) string {
+	return p.cfg.AuthCodeURL(state, opts...)
+}
+
+func (p PlainOauthAuthenticator) Exchange(ctx context.Context, code string, opts ...oauth2.AuthCodeOption) (*oauth2.Token, error) {
+	return p.cfg.Exchange(ctx, code, opts...)
+}
+
+func (p PlainOauthAuthenticator) GetUserInfo(ctx context.Context, token *oauth2.Token, _ string) (map[string]interface{}, error) {
+	req, err := http.NewRequest("GET", p.userInfoEndpoint, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create user info get request: %w", err)
+	}
+	req.Header.Add("Authorization", "Bearer "+token.AccessToken)
+	req.WithContext(ctx)
+
+	response, err := p.client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get user info: %w", err)
+	}
+	defer response.Body.Close()
+	contents, err := io.ReadAll(response.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response body: %w", err)
+	}
+
+	var userFields map[string]interface{}
+	err = json.Unmarshal(contents, &userFields)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse user info: %w", err)
+	}
+
+	return userFields, nil
+}
+
+func (p PlainOauthAuthenticator) ParseUserInfo(raw map[string]interface{}) (*domain.AuthenticatorUserInfo, error) {
+	isAdmin, _ := strconv.ParseBool(internal.MapDefaultString(raw, p.userInfoMapping.IsAdmin, ""))
+	userInfo := &domain.AuthenticatorUserInfo{
+		Identifier: domain.UserIdentifier(internal.MapDefaultString(raw, p.userInfoMapping.UserIdentifier, "")),
+		Email:      internal.MapDefaultString(raw, p.userInfoMapping.Email, ""),
+		Firstname:  internal.MapDefaultString(raw, p.userInfoMapping.Firstname, ""),
+		Lastname:   internal.MapDefaultString(raw, p.userInfoMapping.Lastname, ""),
+		Phone:      internal.MapDefaultString(raw, p.userInfoMapping.Phone, ""),
+		Department: internal.MapDefaultString(raw, p.userInfoMapping.Department, ""),
+		IsAdmin:    isAdmin,
+	}
+
+	return userInfo, nil
+}
+
+func getOauthFieldMapping(f config.OauthFields) config.OauthFields {
+	defaultMap := config.OauthFields{
+		BaseFields: config.BaseFields{
+			UserIdentifier: "sub",
+			Email:          "email",
+			Firstname:      "given_name",
+			Lastname:       "family_name",
+			Phone:          "phone",
+			Department:     "department",
+		},
+		IsAdmin: "admin_flag",
+	}
+	if f.UserIdentifier != "" {
+		defaultMap.UserIdentifier = f.UserIdentifier
+	}
+	if f.Email != "" {
+		defaultMap.Email = f.Email
+	}
+	if f.Firstname != "" {
+		defaultMap.Firstname = f.Firstname
+	}
+	if f.Lastname != "" {
+		defaultMap.Lastname = f.Lastname
+	}
+	if f.Phone != "" {
+		defaultMap.Phone = f.Phone
+	}
+	if f.Department != "" {
+		defaultMap.Department = f.Department
+	}
+	if f.IsAdmin != "" {
+		defaultMap.IsAdmin = f.IsAdmin
+	}
+
+	return defaultMap
+}