MM-15422: Adds new parameters for retrieving pages of channels. (#10903)

* MM-15422: Adds new parameters for retrieving pages of channels and searching channels.

* MM-15422: Appends excluded channel names with defaults. Adds separate struct for data-tier option parameter.

web/params.go

@@ -66,6 +66,8 @@ type Params struct {
 	NotAssociatedToChannel string
 	Paginate               *bool
 	IncludeMemberCount     bool
+	NotAssociatedToGroup   string
+	ExcludeDefaultChannels bool
 }
 
 func ParamsFromRequest(r *http.Request) *Params {
@@ -260,5 +262,11 @@ func ParamsFromRequest(r *http.Request) *Params {
 		params.IncludeMemberCount = val
 	}
 
+	params.NotAssociatedToGroup = query.Get("not_associated_to_group")
+
+	if val, err := strconv.ParseBool(query.Get("exclude_default_channels")); err == nil {
+		params.ExcludeDefaultChannels = val
+	}
+
 	return params
 }