Allow Logging to stdout with separate Error Log Channel (#718)

* Add dedicated error logging writer

* Document new errors to stdout flag

* Update changelog

* Thread-safe the log buffer

* Address feedback

* Remove duplication by adding log level

* Clean up error formatting

* Apply suggestions from code review

Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>

providers/azure.go

@@ -202,12 +202,12 @@ func (p *AzureProvider) GetEmailAddress(ctx context.Context, s *sessions.Session
 
 	email, err = json.Get("userPrincipalName").String()
 	if err != nil {
-		logger.Printf("failed making request %s", err)
+		logger.Errorf("failed making request %s", err)
 		return "", err
 	}
 
 	if email == "" {
-		logger.Printf("failed to get email address")
+		logger.Errorf("failed to get email address")
 		return "", err
 	}
 

providers/bitbucket.go

@@ -107,7 +107,7 @@ func (p *BitbucketProvider) GetEmailAddress(ctx context.Context, s *sessions.Ses
 		Do().
 		UnmarshalInto(&emails)
 	if err != nil {
-		logger.Printf("failed making request: %v", err)
+		logger.Errorf("failed making request: %v", err)
 		return "", err
 	}
 
@@ -123,7 +123,7 @@ func (p *BitbucketProvider) GetEmailAddress(ctx context.Context, s *sessions.Ses
 			Do().
 			UnmarshalInto(&teams)
 		if err != nil {
-			logger.Printf("failed requesting teams membership: %v", err)
+			logger.Errorf("failed requesting teams membership: %v", err)
 			return "", err
 		}
 		var found = false
@@ -134,7 +134,7 @@ func (p *BitbucketProvider) GetEmailAddress(ctx context.Context, s *sessions.Ses
 			}
 		}
 		if !found {
-			logger.Print("team membership test failed, access denied")
+			logger.Error("team membership test failed, access denied")
 			return "", nil
 		}
 	}
@@ -153,7 +153,7 @@ func (p *BitbucketProvider) GetEmailAddress(ctx context.Context, s *sessions.Ses
 			Do().
 			UnmarshalInto(&repositories)
 		if err != nil {
-			logger.Printf("failed checking repository access: %v", err)
+			logger.Errorf("failed checking repository access: %v", err)
 			return "", err
 		}
 
@@ -165,7 +165,7 @@ func (p *BitbucketProvider) GetEmailAddress(ctx context.Context, s *sessions.Ses
 			}
 		}
 		if !found {
-			logger.Print("repository access test failed, access denied")
+			logger.Error("repository access test failed, access denied")
 			return "", nil
 		}
 	}

providers/google.go

@@ -212,7 +212,7 @@ func userInGroup(service *admin.Service, groups []string, email string) bool {
 			gerr, ok := err.(*googleapi.Error)
 			switch {
 			case ok && gerr.Code == 404:
-				logger.Printf("error checking membership in group %s: group does not exist", group)
+				logger.Errorf("error checking membership in group %s: group does not exist", group)
 			case ok && gerr.Code == 400:
 				// It is possible for Members.HasMember to return false even if the email is a group member.
 				// One case that can cause this is if the user email is from a different domain than the group,
@@ -222,7 +222,7 @@ func userInGroup(service *admin.Service, groups []string, email string) bool {
 				r, err := req.Do()
 
 				if err != nil {
-					logger.Printf("error using get API to check member %s of google group %s: user not in the group", email, group)
+					logger.Errorf("error using get API to check member %s of google group %s: user not in the group", email, group)
 					continue
 				}
 
@@ -232,7 +232,7 @@ func userInGroup(service *admin.Service, groups []string, email string) bool {
 					return true
 				}
 			default:
-				logger.Printf("error checking group membership: %v", err)
+				logger.Errorf("error checking group membership: %v", err)
 			}
 			continue
 		}

providers/internal_util.go

@@ -24,14 +24,14 @@ func stripToken(endpoint string) string {
 func stripParam(param, endpoint string) string {
 	u, err := url.Parse(endpoint)
 	if err != nil {
-		logger.Printf("error attempting to strip %s: %s", param, err)
+		logger.Errorf("error attempting to strip %s: %s", param, err)
 		return endpoint
 	}
 
 	if u.RawQuery != "" {
 		values, err := url.ParseQuery(u.RawQuery)
 		if err != nil {
-			logger.Printf("error attempting to strip %s: %s", param, err)
+			logger.Errorf("error attempting to strip %s: %s", param, err)
 			return u.String()
 		}
 
@@ -61,8 +61,8 @@ func validateToken(ctx context.Context, p Provider, accessToken string, header h
 		WithHeaders(header).
 		Do()
 	if result.Error() != nil {
-		logger.Printf("GET %s", stripToken(endpoint))
-		logger.Printf("token validation request failed: %s", result.Error())
+		logger.Errorf("GET %s", stripToken(endpoint))
+		logger.Errorf("token validation request failed: %s", result.Error())
 		return false
 	}
 
@@ -71,6 +71,6 @@ func validateToken(ctx context.Context, p Provider, accessToken string, header h
 	if result.StatusCode() == 200 {
 		return true
 	}
-	logger.Printf("token validation request failed: status %d - %s", result.StatusCode(), result.Body())
+	logger.Errorf("token validation request failed: status %d - %s", result.StatusCode(), result.Body())
 	return false
 }

providers/keycloak.go

@@ -70,7 +70,7 @@ func (p *KeycloakProvider) GetEmailAddress(ctx context.Context, s *sessions.Sess
 		Do().
 		UnmarshalJSON()
 	if err != nil {
-		logger.Printf("failed making request %s", err)
+		logger.Errorf("failed making request %s", err)
 		return "", err
 	}
 

providers/provider_data.go

@@ -39,7 +39,7 @@ func (p *ProviderData) GetClientSecret() (clientSecret string, err error) {
 	// Getting ClientSecret can fail in runtime so we need to report it without returning the file name to the user
 	fileClientSecret, err := ioutil.ReadFile(p.ClientSecretFile)
 	if err != nil {
-		logger.Printf("error reading client secret file %s: %s", p.ClientSecretFile, err)
+		logger.Errorf("error reading client secret file %s: %s", p.ClientSecretFile, err)
 		return "", errors.New("could not read client secret file")
 	}
 	return string(fileClientSecret), nil