gitea: use custom http request for get tokens

Since the get tokens gitea api is used to do auth by username password we need
to know the api status code to detect if it's an unauthorized error (wrong
username/password) or another error.

Since the gitea client doesn't return the http response to inspect the status
code we'll use our own api call.

internal/gitsources/gitea/gitea.go

@@ -17,6 +17,8 @@ package gitea
 import (
 	"context"
 	"crypto/tls"
+	"encoding/base64"
+	"encoding/json"
 	"fmt"
 	"net"
 	"net/http"
@@ -54,6 +56,7 @@ type Opts struct {
 
 type Client struct {
 	client         *gitea.Client
+	httpClient     *http.Client
 	URL            string
 	oauth2ClientID string
 	oauth2Secret   string
@@ -103,6 +106,7 @@ func New(opts Opts) (*Client, error) {
 
 	return &Client{
 		client:         client,
+		httpClient:     httpClient,
 		URL:            opts.URL,
 		oauth2ClientID: opts.Oauth2ClientID,
 		oauth2Secret:   opts.Oauth2Secret,
@@ -145,16 +149,39 @@ func (c *Client) RefreshOauth2Token(refreshToken string) (*oauth2.Token, error)
 
 func (c *Client) LoginPassword(username, password, tokenName string) (string, error) {
 	// try to get agola access token if it already exists
+	// use custom http call since gitea api client doesn't provide an easy way to
+	// guess if the username/password login failed
 	var accessToken string
-	tokens, err := c.client.ListAccessTokens(username, password)
-	if err == nil {
+
+	tokens := make([]*gitea.AccessToken, 0, 10)
+	req, err := http.NewRequest("GET", c.URL+"/api/v1"+fmt.Sprintf("/users/%s/tokens", username), nil)
+	if err != nil {
+		return "", err
+	}
+	req.Header.Set("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(username+":"+password)))
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return "", err
+	}
+	if resp.StatusCode == http.StatusUnauthorized {
+		return "", gitsource.ErrUnauthorized
+	}
+	if resp.StatusCode/100 != 2 {
+		return "", errors.Errorf("gitea api status code %d", resp.StatusCode)
+	}
+	defer resp.Body.Close()
+
+	dec := json.NewDecoder(resp.Body)
+	if err := dec.Decode(&tokens); err != nil {
+		return "", err
+	}
 	for _, token := range tokens {
 		if token.Name == tokenName {
 			accessToken = token.Sha1
 			break
 		}
 	}
-	}
 
 	// create access token
 	if accessToken == "" {

internal/gitsources/gitsource.go

@@ -15,6 +15,7 @@
 package gitsource
 
 import (
+	"errors"
 	"net/http"
 
 	"github.com/sorintlab/agola/internal/services/types"
@@ -29,6 +30,8 @@ const (
 	CommitStatusFailed  CommitStatus = "failed"
 )
 
+var ErrUnauthorized = errors.New("unauthorized")
+
 type GitSource interface {
 	GetRepoInfo(repopath string) (*RepoInfo, error)
 	GetFile(repopath, commit, file string) ([]byte, error)