hugo/tpl/os/os.go
2017-06-13 19:12:10 +02:00

98 lines
2.6 KiB
Go

// Copyright 2017 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package os
import (
"errors"
"fmt"
_os "os"
"github.com/gohugoio/hugo/deps"
"github.com/spf13/afero"
"github.com/spf13/cast"
)
// New returns a new instance of the os-namespaced template functions.
func New(deps *deps.Deps) *Namespace {
return &Namespace{
deps: deps,
}
}
// Namespace provides template functions for the "os" namespace.
type Namespace struct {
deps *deps.Deps
}
// Getenv retrieves the value of the environment variable named by the key.
// It returns the value, which will be empty if the variable is not present.
func (ns *Namespace) Getenv(key interface{}) (string, error) {
skey, err := cast.ToStringE(key)
if err != nil {
return "", nil
}
return _os.Getenv(skey), nil
}
// readFile reads the file named by filename relative to the given basepath
// and returns the contents as a string.
// There is a upper size limit set at 1 megabytes.
func readFile(fs *afero.BasePathFs, filename string) (string, error) {
if filename == "" {
return "", errors.New("readFile needs a filename")
}
if info, err := fs.Stat(filename); err == nil {
if info.Size() > 1000000 {
return "", fmt.Errorf("File %q is too big", filename)
}
} else {
return "", err
}
b, err := afero.ReadFile(fs, filename)
if err != nil {
return "", err
}
return string(b), nil
}
// ReadFilereads the file named by filename relative to the configured
// WorkingDir. It returns the contents as a string. There is a upper size
// limit set at 1 megabytes.
func (ns *Namespace) ReadFile(i interface{}) (string, error) {
s, err := cast.ToStringE(i)
if err != nil {
return "", err
}
return readFile(ns.deps.Fs.WorkingDir, s)
}
// ReadDir lists the directory contents relative to the configured WorkingDir.
func (ns *Namespace) ReadDir(i interface{}) ([]_os.FileInfo, error) {
path, err := cast.ToStringE(i)
if err != nil {
return nil, err
}
list, err := afero.ReadDir(ns.deps.Fs.WorkingDir, path)
if err != nil {
return nil, fmt.Errorf("Failed to read Directory %s with error message %s", path, err)
}
return list, nil
}