voicera/gooseberry

// This program generates URN helper functions.
package main

import (
    "flag"
    "fmt"
    "os"
    "strings"
    "text/template"
)

const sourceFileTemplateText = `package %s // auto-generated using make - DO NOT EDIT!

import (
    "strings"

    "github.com/voicera/gooseberry/urn"
)
{{range $funcName, $namespaceID := .}}
// New{{$funcName}}URN creates a new URN with the "{{$namespaceID}}"
// namespace ID.
func New{{$funcName}}URN(namespaceSpecificString string) *urn.URN {
    return urn.NewURN("{{$namespaceID}}", namespaceSpecificString)
}

// Is{{$funcName}}URN determines whether the specified URN uses
// "{{$namespaceID}}" as its namespace ID.
func Is{{$funcName}}URN(u *urn.URN) bool {
    return strings.EqualFold(u.GetNamespaceID(), "{{$namespaceID}}")
}

// Is{{$funcName}}URNWithValue determines whether the specified URN uses
// "{{$namespaceID}}" as its namespace ID and the specified
// namespaceSpecificString as its namespace-specific string.
func Is{{$funcName}}URNWithValue(u *urn.URN, namespaceSpecificString string) bool {
    return Is{{$funcName}}URN(u) && strings.EqualFold(u.GetNamespaceSpecificString(), namespaceSpecificString)
}
{{end}}`

var (
    sourceFileTemplate *template.Template
    // We autogenerate URN functions from the map below; add a new namespace ID
    // here and map it to a function name suffix.
    funcNameSuffixToNamespaceID = map[string]string{}
)

func init() {
    packageName := flag.String("p", "urns", "name of auto-generated package.")
    mapping := flag.String("m", "", "func names suffixes to namespace IDs; e.g., 'User=user Email=email'")
    flag.Parse()
    if *mapping == "" {
        flag.Usage()
        fmt.Println(`Example: go run scripts/urns/main.go -p urns -m "User=user Email=email"`)
        os.Exit(1)
    }
    sourceFileTemplate = template.Must(template.New("").Parse(fmt.Sprintf(sourceFileTemplateText, *packageName)))
    for _, m := range strings.Split(*mapping, " ") {
        indexOfMapper := strings.IndexRune(m, '=')
        funcNameSuffixToNamespaceID[m[:indexOfMapper]] = m[indexOfMapper+1:]
    }
}

func main() {
    if err := sourceFileTemplate.Execute(os.Stdout, funcNameSuffixToNamespaceID); err != nil {
        panic(err)
    }
}