[MM-39597] Implement ConfigDiffs.Sanitize() (#18855)

* Implement ConfigDiffs.Sanitize()

* Remove possibly sensitive info from logs

model/config.go

@@ -3746,9 +3746,11 @@ func (o *Config) Sanitize() {
 		*o.LdapSettings.BindPassword = FakeSetting
 	}
 
-	*o.FileSettings.PublicLinkSalt = FakeSetting
+	if o.FileSettings.PublicLinkSalt != nil {
+		*o.FileSettings.PublicLinkSalt = FakeSetting
+	}
 
-	if *o.FileSettings.AmazonS3SecretAccessKey != "" {
+	if o.FileSettings.AmazonS3SecretAccessKey != nil && *o.FileSettings.AmazonS3SecretAccessKey != "" {
 		*o.FileSettings.AmazonS3SecretAccessKey = FakeSetting
 	}
 
@@ -3756,7 +3758,7 @@ func (o *Config) Sanitize() {
 		*o.EmailSettings.SMTPPassword = FakeSetting
 	}
 
-	if *o.GitLabSettings.Secret != "" {
+	if o.GitLabSettings.Secret != nil && *o.GitLabSettings.Secret != "" {
 		*o.GitLabSettings.Secret = FakeSetting
 	}
 
@@ -3772,10 +3774,17 @@ func (o *Config) Sanitize() {
 		*o.OpenIdSettings.Secret = FakeSetting
 	}
 
-	*o.SqlSettings.DataSource = FakeSetting
-	*o.SqlSettings.AtRestEncryptKey = FakeSetting
+	if o.SqlSettings.DataSource != nil {
+		*o.SqlSettings.DataSource = FakeSetting
+	}
 
-	*o.ElasticsearchSettings.Password = FakeSetting
+	if o.SqlSettings.AtRestEncryptKey != nil {
+		*o.SqlSettings.AtRestEncryptKey = FakeSetting
+	}
+
+	if o.ElasticsearchSettings.Password != nil {
+		*o.ElasticsearchSettings.Password = FakeSetting
+	}
 
 	for i := range o.SqlSettings.DataSourceReplicas {
 		o.SqlSettings.DataSourceReplicas[i] = FakeSetting
@@ -3785,7 +3794,9 @@ func (o *Config) Sanitize() {
 		o.SqlSettings.DataSourceSearchReplicas[i] = FakeSetting
 	}
 
-	if o.MessageExportSettings.GlobalRelaySettings.SMTPPassword != nil && *o.MessageExportSettings.GlobalRelaySettings.SMTPPassword != "" {
+	if o.MessageExportSettings.GlobalRelaySettings != nil &&
+		o.MessageExportSettings.GlobalRelaySettings.SMTPPassword != nil &&
+		*o.MessageExportSettings.GlobalRelaySettings.SMTPPassword != "" {
 		*o.MessageExportSettings.GlobalRelaySettings.SMTPPassword = FakeSetting
 	}
 
@@ -3793,7 +3804,9 @@ func (o *Config) Sanitize() {
 		*o.ServiceSettings.GfycatAPISecret = FakeSetting
 	}
 
-	*o.ServiceSettings.SplitKey = FakeSetting
+	if o.ServiceSettings.SplitKey != nil {
+		*o.ServiceSettings.SplitKey = FakeSetting
+	}
 }
 
 // structToMapFilteredByTag converts a struct into a map removing those fields that has the tag passed