Flow/go/src/flow/registry/describer.go

package registry

// Description of an entry
type Description struct {
	Name string   `json:"name"`
	Desc string   `json:"description"`
	Tags []string `json:"categories"`

	//InputType
	Inputs []DescType `json:"inputs"`
	Output DescType   `json:"output"`

	Extra map[string]interface{} `json:"extra"`
}

//EDescriber helper to batch set properties
type EDescriber []*Entry

// Describer returns a batch of entries for easy manipulation
func Describer(params ...interface{}) EDescriber {
	ret := EDescriber{}
	for _, el := range params {
		switch v := el.(type) {
		case EDescriber:
			ret = append(ret, v...)
		case *Entry:
			ret = append(ret, v)
		}
	}
	return ret
}

// Description set node description
func (d EDescriber) Description(m string) EDescriber {
	for _, e := range d {
		if e.Description == nil {
			continue
		}

		e.Description.Desc = m
	}
	return d

}

//Tags set categories of the group
func (d EDescriber) Tags(tags ...string) EDescriber {
	for _, e := range d {
		if e.Description == nil {
			continue
		}
		e.Description.Tags = tags
	}
	return d
}

// Inputs describe inputs
func (d EDescriber) Inputs(inputs ...string) EDescriber {
	for _, e := range d {
		if e.Description == nil {
			continue
		}

		for i, dstr := range inputs {
			if i >= len(e.Description.Inputs) { // do nothing
				break // next entry
			}
			curDesc := e.Description.Inputs[i]
			e.Description.Inputs[i] = DescType{curDesc.Type, dstr}
		}
	}
	return d
}

// Output describe the output
func (d EDescriber) Output(output string) EDescriber {
	for _, e := range d {
		if e.Description == nil {
			continue
		}
		e.Description.Output = DescType{e.Description.Output.Type, output}
	}
	return d
}

// Extra set extras of the group
func (d EDescriber) Extra(name string, value interface{}) EDescriber {
	for _, e := range d {
		if e.Description == nil {
			continue
		}
		e.Description.Extra[name] = value
	}
	return d
}