Add filters to listing different resources in the go sdk. (#957)

internal/api/genapi/templates.go

@@ -657,6 +657,7 @@ type options struct {
 	queryMap map[string]string
 	withAutomaticVersioning bool
 	withSkipCurlOutput bool
+	withFilter string
 	{{ if .RecursiveListing }} withRecursive bool {{ end }}
 }
 
@@ -675,7 +676,10 @@ func getOpts(opt ...Option) (options, []api.Option) {
 	var apiOpts []api.Option
 	if opts.withSkipCurlOutput {
 		apiOpts = append(apiOpts, api.WithSkipCurlOutput(true))
-	} {{ if .RecursiveListing }}
+	}
+	if opts.withFilter != "" {
+		opts.queryMap["filter"] = opts.withFilter
+	}{{ if .RecursiveListing }}
 	if opts.withRecursive {
 		opts.queryMap["recursive"] = strconv.FormatBool(opts.withRecursive)
 	} {{ end }}
@@ -699,6 +703,15 @@ func WithSkipCurlOutput(skip bool) Option {
 		o.withSkipCurlOutput = true
 	}
 }
+
+// WithFilter tells the API to filter the items returned using the provided
+// filter term.  The filter should be in a format supported by
+// hashicorp/go-bexpr.
+func WithFilter(filter string) Option {
+	return func(o *options) {
+		o.withFilter = strings.TrimSpace(filter)
+	}
+}
 {{ if .RecursiveListing }}
 // WithRecursive tells the API to use recursion for listing operations on this
 // resource