@@ -623,6 +623,11 @@ func (b *Builder) getParameters() (names, values []string, err error) {
623623return nil ,nil ,BuildError {http .StatusBadRequest ,"Unable to build workspace with unsupported parameters" ,err }
624624}
625625
626+ lastBuildParameterValues := db2sdk .WorkspaceBuildParameters (lastBuildParameters )
627+ resolver := codersdk.ParameterResolver {
628+ Rich :lastBuildParameterValues ,
629+ }
630+
626631// Dynamic parameters skip all parameter validation.
627632// Deleting a workspace also should skip parameter validation.
628633// Pass the user's input as is.
@@ -632,19 +637,33 @@ func (b *Builder) getParameters() (names, values []string, err error) {
632637// conditional parameter existence, the static frame of reference
633638// is not sufficient. So assume the user is correct, or pull in the
634639// dynamic param code to find the actual parameters.
640+ latestValues := make (map [string ]string )
641+ for _ ,latest := range b .richParameterValues {
642+ latestValues [latest .Name ]= latest .Value
643+ }
644+
645+ // Merge the inputs with values from the previous build.
646+ for _ ,last := range lastBuildParameterValues {
647+ // TODO: Ideally we use the resolver here and look at parameter
648+ // fields such as 'ephemeral'. This requires loading the terraform
649+ // files. For now, just send the previous inputs as is.
650+ if _ ,exists := latestValues [last .Name ];exists {
651+ continue
652+ }
653+ names = append (names ,last .Name )
654+ values = append (values ,last .Value )
655+ }
656+
635657for _ ,value := range b .richParameterValues {
636658names = append (names ,value .Name )
637659values = append (values ,value .Value )
638660}
661+
639662b .parameterNames = & names
640663b .parameterValues = & values
641664return names ,values ,nil
642665}
643666
644- resolver := codersdk.ParameterResolver {
645- Rich :db2sdk .WorkspaceBuildParameters (lastBuildParameters ),
646- }
647-
648667for _ ,templateVersionParameter := range templateVersionParameters {
649668tvp ,err := db2sdk .TemplateVersionParameter (templateVersionParameter )
650669if err != nil {