%PDF-
%PDF-
Mini Shell
Mini Shell
package namespace
// Enables you do define clauses that will be added to separate namespaces.
// By default anything in an undefined namespace is added to the global namespace.
// A namespace is defined by:
// namespace := "[" + token "]"
// token := [^/](ie not "/") + ("/" + token)*
// ie (non "/" character) + (optionally "/" + non "/" character)
//
// For example:
// [global]
// [pull/push]
//
// Empty spaces are skipped over and not
import (
"fmt"
"io"
"strings"
"github.com/odeke-em/go-utils/fread"
)
const (
commonCommandDelim = "/"
lBrace = "["
rBrace = "]"
GlobalNamespaceKey = "global"
)
type type_ uint
const (
tUnknown type_ = iota
tNamespace
tClause
)
func classify(line string) type_ {
line = strings.TrimSpace(line)
if strings.HasPrefix(line, lBrace) {
return tNamespace
}
return tClause
}
type Namespace map[string][]string
func Parse(r io.Reader) (Namespace, error) {
// Expecting the form
// [command]
// key=value
lines := fread.Fread(r)
return ParseCh(lines)
}
func ParseCh(lines <-chan string) (Namespace, error) {
type nsSetter func(values ...string)
ns := make(Namespace)
makeNSSetter := func(nsKeys ...string) nsSetter {
return func(values ...string) {
for _, nsKey := range nsKeys {
if nsKey == "" {
nsKey = GlobalNamespaceKey
}
ns[nsKey] = append(ns[nsKey], values...)
}
}
}
globalNSSetter := makeNSSetter(GlobalNamespaceKey)
var lastNSSetter nsSetter = globalNSSetter
lineno := uint64(0)
for line := range lines {
typ := classify(line)
lineno += 1
switch typ {
case tNamespace:
namespaceKeys, err := parseOutNamespaceHeaders(line)
if err != nil {
return nil, err
}
lastNSSetter = makeNSSetter(namespaceKeys...)
case tClause:
clause, err := parseOutClause(line)
if err != nil {
return nil, err
}
if clause != "" {
lastNSSetter(clause)
}
}
}
return ns, nil
}
func parseOutClause(line string) (string, error) {
line = strings.TrimSpace(line)
return line, nil
}
func parseOutNamespaceHeaders(line string) ([]string, error) {
line = strings.TrimSpace(line)
lbc, rbc := strings.Count(line, lBrace), strings.Count(line, rBrace)
if lbc != 1 {
return nil, fmt.Errorf("expecting exactly 1 %q got %s", lBrace, line)
}
if rbc != 1 {
return nil, fmt.Errorf("expecting exactly 1 %q", rBrace)
}
lbi, rbi := strings.Index(line, lBrace), strings.Index(line, rBrace)
if lbi >= rbi {
return nil, fmt.Errorf("%q must be before %q", lBrace, rBrace)
}
namespaceName := line[lbi+1 : rbi]
splits := strings.Split(namespaceName, commonCommandDelim)
return prepareNamespaceKeys(splits), nil
}
func prepareNamespaceKeys(keys []string) []string {
var cleaned []string
for _, key := range keys {
key = strings.TrimSpace(key)
if key != "" {
cleaned = append(cleaned, key)
}
}
if len(keys) >= 1 && len(cleaned) < 1 {
// They wanted the global namespace but due to our strict policy
// of ignoring empty keys, we'll just reset to the globalNamespace
cleaned = []string{GlobalNamespaceKey}
}
return cleaned
}
Zerion Mini Shell 1.0