Merge pull request #8 from auth0/a0cli-4

[A0CLI-4] feat: initial implementation of try-login

internal/auth/auth.go

@@ -33,7 +33,7 @@ const (
 	deviceCodeEndpoint = "https://auth0.auth0.com/oauth/device/code"
 	oauthTokenEndpoint = "https://auth0.auth0.com/oauth/token"
 	// TODO(jfatta) extend the scope as we extend the CLI:
-	scope        = "openid create:actions create:clients create:resource_servers create:connections create:hooks create:rules delete:actions delete:clients delete:connections delete:hooks delete:rules read:actions read:clients read:resource_servers read:connections read:hooks read:logs read:rules update:actions update:clients update:resource_servers update:connections update:hooks update:rules"
+	scope        = "openid create:actions create:clients create:resource_servers create:connections create:hooks create:rules delete:actions delete:clients delete:connections delete:hooks delete:rules read:actions read:clients read:client_keys read:resource_servers read:connections read:hooks read:logs read:rules update:actions update:clients update:resource_servers update:connections update:hooks update:rules"
 	audiencePath = "/api/v2/"
 )
 

internal/auth/exchange.go

@@ -0,0 +1,48 @@
+package auth
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+)
+
+// TokenResponse stores token information as retrieved from the /oauth/token
+// endpoint when exchanging a code.
+type TokenResponse struct {
+	AccessToken  string `json:"access_token,omitempty"`
+	RefreshToken string `json:"refresh_token,omitempty"`
+	IDToken      string `json:"id_token,omitempty"`
+	TokenType    string `json:"token_type,omitempty"`
+	ExpiresIn    int64  `json:"expires_in,omitempty"`
+}
+
+// ExchangeCodeForToken fetches an access token for the given client using the provided code.
+func ExchangeCodeForToken(baseDomain, clientID, clientSecret, code, cbURL string) (*TokenResponse, error) {
+	data := url.Values{
+		"grant_type":    {"authorization_code"},
+		"client_id":     {clientID},
+		"client_secret": {clientSecret},
+		"code":          {code},
+		"redirect_uri":  {cbURL},
+	}
+
+	u := url.URL{Scheme: "https", Host: baseDomain, Path: "/oauth/token"}
+	r, err := http.PostForm(u.String(), data)
+	if err != nil {
+		return nil, fmt.Errorf("unable to exchange code for token: %w", err)
+	}
+	defer r.Body.Close()
+
+	if r.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unable to exchange code for token: %s", r.Status)
+	}
+
+	var res *TokenResponse
+	err = json.NewDecoder(r.Body).Decode(&res)
+	if err != nil {
+		return nil, fmt.Errorf("cannot decode response: %w", err)
+	}
+
+	return res, nil
+}

internal/auth/user_info.go

@@ -0,0 +1,61 @@
+package auth
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+// UserInfo contains profile information for a given OIDC user.
+type UserInfo struct {
+	Sub               *string    `json:"sub,omitempty"`
+	Name              *string    `json:"name,omitempty"`
+	GivenName         *string    `json:"given_name,omitempty"`
+	MiddleName        *string    `json:"middle_name,omitempty"`
+	FamilyName        *string    `json:"family_name,omitempty"`
+	Nickname          *string    `json:"nickname,omitempty"`
+	PreferredUsername *string    `json:"preferred_username,omitempty"`
+	Profile           *string    `json:"profile,omitempty"`
+	Picture           *string    `json:"picture,omitempty"`
+	Website           *string    `json:"website,omitempty"`
+	PhoneNumber       *string    `json:"phone_number,omitempty"`
+	PhoneVerified     *bool      `json:"phone_verified,omitempty"`
+	Email             *string    `json:"email,omitempty"`
+	EmailVerified     *bool      `json:"email_verified,omitempty"`
+	Gender            *string    `json:"gender,omitempty"`
+	BirthDate         *string    `json:"birthdate,omitempty"`
+	ZoneInfo          *string    `json:"zoneinfo,omitempty"`
+	Locale            *string    `json:"locale,omitempty"`
+	UpdatedAt         *time.Time `json:"updated_at,omitempty"`
+}
+
+// FetchUserInfo fetches and parses user information with the provided access token.
+func FetchUserInfo(baseDomain, token string) (*UserInfo, error) {
+	endpoint := url.URL{Scheme: "https", Host: baseDomain, Path: "/userinfo"}
+
+	req, err := http.NewRequest("GET", endpoint.String(), nil)
+	if err != nil {
+		return nil, fmt.Errorf("unable to exchange code for token: %w", err)
+	}
+	req.Header.Set("authorization", fmt.Sprintf("Bearer %s", token))
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("unable to exchange code for token: %w", err)
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unable to fetch user info: %s", res.Status)
+	}
+
+	var u *UserInfo
+	err = json.NewDecoder(res.Body).Decode(&u)
+	if err != nil {
+		return nil, fmt.Errorf("cannot decode response: %w", err)
+	}
+
+	return u, nil
+}

internal/cli/root.go

@@ -57,10 +57,7 @@ func Execute() {
 	rootCmd.AddCommand(actionsCmd(cli))
 	rootCmd.AddCommand(rulesCmd(cli))
 	rootCmd.AddCommand(connectionsCmd(cli))
-
-	// TODO(cyx): backport this later on using latest auth0/v5.
-	// rootCmd.AddCommand(actionsCmd(cli))
-	// rootCmd.AddCommand(triggersCmd(cli))
+	rootCmd.AddCommand(tryLoginCmd(cli))
 
 	if err := rootCmd.ExecuteContext(context.TODO()); err != nil {
 		cli.renderer.Errorf(err.Error())

internal/cli/try_login.go

@@ -0,0 +1,206 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/auth0/auth0-cli/internal/auth"
+	"github.com/auth0/auth0-cli/internal/open"
+	"github.com/spf13/cobra"
+	"gopkg.in/auth0.v5"
+	"gopkg.in/auth0.v5/management"
+)
+
+const (
+	cliLoginTestingClientName        string = "CLI Login Testing"
+	cliLoginTestingClientDescription string = "A client used for testing logins using the Auth0 CLI."
+	cliLoginTestingCallbackAddr      string = "localhost:8484"
+	cliLoginTestingCallbackURL       string = "http://localhost:8484"
+	cliLoginTestingInitiateLoginURI  string = "https://cli.auth0.com"
+	cliLoginTestingScopes            string = "openid profile"
+)
+
+func tryLoginCmd(cli *cli) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "try-login",
+		Short: "Try out your universal login box",
+		Long: `$ auth0 try-login
+Launch a browser to try out your universal login box for the given client.
+`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			tenant, err := cli.getTenant()
+			if err != nil {
+				return err
+			}
+
+			// use the client ID as passed in by the user, or default to the
+			// "CLI Login Testing" client if none passed. This client is only
+			// used for testing login from the CLI and will be created if it
+			// does not exist.
+			clientID, _ := cmd.Flags().GetString("client-id")
+			if clientID == "" {
+				client, err := getOrCreateCLITesterClient(cli.api.Client)
+				if err != nil {
+					return err
+				}
+				clientID = client.GetClientID()
+			}
+
+			client, err := cli.api.Client.Read(clientID)
+			if err != nil {
+				return err
+			}
+
+			// check if the client's initiate_login_uri matches the one for our
+			// "CLI Login Testing" app. If so, then initiate the login via the
+			// `/authorize` endpoint, if not, open a browser at the client's
+			// configured URL. If none is specified, return an error to the
+			// caller explaining the problem.
+			if client.GetInitiateLoginURI() == "" {
+				return fmt.Errorf(
+					"client %s does not specify a URL with which to initiate login",
+					client.GetClientID(),
+				)
+			}
+
+			if client.GetInitiateLoginURI() != cliLoginTestingInitiateLoginURI {
+				return open.URL(client.GetInitiateLoginURI())
+			}
+
+			// Build a login URL and initiate login in a browser window.
+			loginURL, err := buildInitiateLoginURL(tenant.Domain, client.GetClientID())
+			if err != nil {
+				return err
+			}
+
+			if err := open.URL(loginURL); err != nil {
+				return err
+			}
+
+			// launch a HTTP server to wait for the callback to capture the auth
+			// code.
+			authCode, err := waitForBrowserCallback()
+			if err != nil {
+				return err
+			}
+
+			// once the callback is received, exchange the code for an access
+			// token.
+			tokenResponse, err := auth.ExchangeCodeForToken(
+				tenant.Domain,
+				client.GetClientID(),
+				client.GetClientSecret(),
+				authCode,
+				cliLoginTestingCallbackURL,
+			)
+			if err != nil {
+				return fmt.Errorf("%w", err)
+			}
+
+			// Use the access token to fetch user information from the /userinfo
+			// endpoint.
+			userInfo, err := auth.FetchUserInfo(tenant.Domain, tokenResponse.AccessToken)
+			if err != nil {
+				return err
+			}
+
+			reveal, _ := cmd.Flags().GetBool("reveal")
+			cli.renderer.TryLogin(userInfo, tokenResponse, reveal)
+			return nil
+		},
+	}
+
+	cmd.SetUsageTemplate(resourceUsageTemplate())
+	cmd.Flags().StringP("client-id", "c", "", "Client ID for which to test login.")
+	cmd.Flags().BoolP("reveal", "r", false, "⚠️  Reveal tokens after successful login.")
+	return cmd
+}
+
+// getOrCreateCLITesterClient uses the manage API to look for an existing client
+// named `cliLoginTestingClientName`, and if it doesn't find one creates it with
+// default settings.
+func getOrCreateCLITesterClient(clientManager *management.ClientManager) (*management.Client, error) {
+	clients, err := clientManager.List()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, client := range clients.Clients {
+		if client.GetName() == cliLoginTestingClientName {
+			return client, nil
+		}
+	}
+
+	// we couldn't find the default client, so let's create it
+	client := &management.Client{
+		Name:             auth0.String(cliLoginTestingClientName),
+		Description:      auth0.String(cliLoginTestingClientDescription),
+		Callbacks:        []interface{}{cliLoginTestingCallbackURL},
+		InitiateLoginURI: auth0.String(cliLoginTestingInitiateLoginURI),
+	}
+	return client, clientManager.Create(client)
+}
+
+// buildInitiateLoginURL constructs a URL + query string that can be used to
+// initiate a login-flow from the CLI.
+func buildInitiateLoginURL(domain, clientID string) (string, error) {
+	var path string = "/authorize"
+
+	q := url.Values{}
+	q.Add("client_id", clientID)
+	q.Add("response_type", "code")
+	q.Add("prompt", "login")
+	q.Add("scope", cliLoginTestingScopes)
+	q.Add("redirect_uri", cliLoginTestingCallbackURL)
+
+	u := &url.URL{
+		Scheme:   "https",
+		Host:     domain,
+		Path:     path,
+		RawQuery: q.Encode(),
+	}
+
+	return u.String(), nil
+}
+
+// waitForBrowserCallback lauches a new HTTP server listening on
+// `cliLoginTestingCallbackAddr` and waits for a request. Once received, the
+// `code` is extracted from the query string (if any), and returns it to the
+// caller.
+func waitForBrowserCallback() (string, error) {
+	codeCh := make(chan string)
+	errCh := make(chan error)
+
+	m := http.NewServeMux()
+	s := http.Server{Addr: cliLoginTestingCallbackAddr, Handler: m}
+
+	m.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		authCode := r.URL.Query().Get("code")
+		if authCode == "" {
+			_, _ = w.Write([]byte("<p>&#10060; Unable to extract code from request, please try authenticating again</p>"))
+		} else {
+			_, _ = w.Write([]byte("<p>&#128075; You can close the window and go back to the CLI to see the user info and tokens</p>"))
+		}
+		codeCh <- authCode
+	})
+
+	go func() {
+		if err := s.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			errCh <- err
+		}
+	}()
+
+	select {
+	case code := <-codeCh:
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+
+		err := s.Shutdown(ctx)
+		return code, err
+	case err := <-errCh:
+		return "", err
+	}
+}