refactor: split handlers into smaller purpose specific files

internal/handlers/oauth.go

@@ -0,0 +1,223 @@
+package handlers
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+	"tinyauth/internal/types"
+	"tinyauth/internal/utils"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/go-querystring/query"
+	"github.com/rs/zerolog/log"
+)
+
+func (h *Handlers) OAuthURLHandler(c *gin.Context) {
+	var request types.OAuthRequest
+
+	err := c.BindUri(&request)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to bind URI")
+		c.JSON(400, gin.H{
+			"status":  400,
+			"message": "Bad Request",
+		})
+		return
+	}
+
+	log.Debug().Msg("Got OAuth request")
+
+	// Check if provider exists
+	provider := h.Providers.GetProvider(request.Provider)
+
+	if provider == nil {
+		c.JSON(404, gin.H{
+			"status":  404,
+			"message": "Not Found",
+		})
+		return
+	}
+
+	log.Debug().Str("provider", request.Provider).Msg("Got provider")
+
+	// Create state
+	state := provider.GenerateState()
+
+	// Get auth URL
+	authURL := provider.GetAuthURL(state)
+
+	log.Debug().Msg("Got auth URL")
+
+	// Set CSRF cookie
+	c.SetCookie(h.Config.CsrfCookieName, state, int(time.Hour.Seconds()), "/", "", h.Config.CookieSecure, true)
+
+	// Get redirect URI
+	redirectURI := c.Query("redirect_uri")
+
+	// Set redirect cookie if redirect URI is provided
+	if redirectURI != "" {
+		log.Debug().Str("redirectURI", redirectURI).Msg("Setting redirect cookie")
+		c.SetCookie(h.Config.RedirectCookieName, redirectURI, int(time.Hour.Seconds()), "/", "", h.Config.CookieSecure, true)
+	}
+
+	// Return auth URL
+	c.JSON(200, gin.H{
+		"status":  200,
+		"message": "OK",
+		"url":     authURL,
+	})
+}
+
+func (h *Handlers) OAuthCallbackHandler(c *gin.Context) {
+	var providerName types.OAuthRequest
+
+	err := c.BindUri(&providerName)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to bind URI")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	log.Debug().Interface("provider", providerName.Provider).Msg("Got provider name")
+
+	// Get state
+	state := c.Query("state")
+
+	// Get CSRF cookie
+	csrfCookie, err := c.Cookie(h.Config.CsrfCookieName)
+
+	if err != nil {
+		log.Debug().Msg("No CSRF cookie")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	log.Debug().Str("csrfCookie", csrfCookie).Msg("Got CSRF cookie")
+
+	// Check if CSRF cookie is valid
+	if csrfCookie != state {
+		log.Warn().Msg("Invalid CSRF cookie or CSRF cookie does not match with the state")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	// Clean up CSRF cookie
+	c.SetCookie(h.Config.CsrfCookieName, "", -1, "/", "", h.Config.CookieSecure, true)
+
+	// Get code
+	code := c.Query("code")
+
+	log.Debug().Msg("Got code")
+
+	// Get provider
+	provider := h.Providers.GetProvider(providerName.Provider)
+
+	if provider == nil {
+		c.Redirect(http.StatusTemporaryRedirect, "/not-found")
+		return
+	}
+
+	log.Debug().Str("provider", providerName.Provider).Msg("Got provider")
+
+	// Exchange token (authenticates user)
+	_, err = provider.ExchangeToken(code)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to exchange token")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	log.Debug().Msg("Got token")
+
+	// Get user
+	user, err := h.Providers.GetUser(providerName.Provider)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to get user")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	log.Debug().Msg("Got user")
+
+	// Check that email is not empty
+	if user.Email == "" {
+		log.Error().Msg("Email is empty")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	// Email is not whitelisted
+	if !h.Auth.EmailWhitelisted(user.Email) {
+		log.Warn().Str("email", user.Email).Msg("Email not whitelisted")
+		queries, err := query.Values(types.UnauthorizedQuery{
+			Username: user.Email,
+		})
+
+		if err != nil {
+			log.Error().Err(err).Msg("Failed to build queries")
+			c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+			return
+		}
+
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/unauthorized?%s", h.Config.AppURL, queries.Encode()))
+	}
+
+	log.Debug().Msg("Email whitelisted")
+
+	// Get username
+	var username string
+
+	if user.PreferredUsername != "" {
+		username = user.PreferredUsername
+	} else {
+		username = fmt.Sprintf("%s_%s", strings.Split(user.Email, "@")[0], strings.Split(user.Email, "@")[1])
+	}
+
+	// Get name
+	var name string
+
+	if user.Name != "" {
+		name = user.Name
+	} else {
+		name = fmt.Sprintf("%s (%s)", utils.Capitalize(strings.Split(user.Email, "@")[0]), strings.Split(user.Email, "@")[1])
+	}
+
+	// Create session cookie
+	h.Auth.CreateSessionCookie(c, &types.SessionCookie{
+		Username:    username,
+		Name:        name,
+		Email:       user.Email,
+		Provider:    providerName.Provider,
+		OAuthGroups: strings.Join(user.Groups, ","),
+	})
+
+	// Check if we have a redirect URI
+	redirectCookie, err := c.Cookie(h.Config.RedirectCookieName)
+
+	if err != nil {
+		log.Debug().Msg("No redirect cookie")
+		c.Redirect(http.StatusTemporaryRedirect, h.Config.AppURL)
+		return
+	}
+
+	log.Debug().Str("redirectURI", redirectCookie).Msg("Got redirect URI")
+
+	queries, err := query.Values(types.LoginQuery{
+		RedirectURI: redirectCookie,
+	})
+
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to build queries")
+		c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/error", h.Config.AppURL))
+		return
+	}
+
+	log.Debug().Msg("Got redirect query")
+
+	// Clean up redirect cookie
+	c.SetCookie(h.Config.RedirectCookieName, "", -1, "/", "", h.Config.CookieSecure, true)
+
+	// Redirect to continue with the redirect URI
+	c.Redirect(http.StatusTemporaryRedirect, fmt.Sprintf("%s/continue?%s", h.Config.AppURL, queries.Encode()))
+}