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// Copyright 2017 Frank Schroeder. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package properties
import (
"fmt"
"io/ioutil"
"net/http"
"os"
"strings"
)
// Encoding specifies encoding of the input data.
type Encoding uint
const (
// UTF8 interprets the input data as UTF-8.
UTF8 Encoding = 1 << iota
// ISO_8859_1 interprets the input data as ISO-8859-1.
ISO_8859_1
)
// Load reads a buffer into a Properties struct.
func Load(buf []byte, enc Encoding) (*Properties, error) {
return loadBuf(buf, enc)
}
// LoadString reads an UTF8 string into a properties struct.
func LoadString(s string) (*Properties, error) {
return loadBuf([]byte(s), UTF8)
}
// LoadMap creates a new Properties struct from a string map.
func LoadMap(m map[string]string) *Properties {
p := NewProperties()
for k, v := range m {
p.Set(k, v)
}
return p
}
// LoadFile reads a file into a Properties struct.
func LoadFile(filename string, enc Encoding) (*Properties, error) {
return loadAll([]string{filename}, enc, false)
}
// LoadFiles reads multiple files in the given order into
// a Properties struct. If 'ignoreMissing' is true then
// non-existent files will not be reported as error.
func LoadFiles(filenames []string, enc Encoding, ignoreMissing bool) (*Properties, error) {
return loadAll(filenames, enc, ignoreMissing)
}
// LoadURL reads the content of the URL into a Properties struct.
//
// The encoding is determined via the Content-Type header which
// should be set to 'text/plain'. If the 'charset' parameter is
// missing, 'iso-8859-1' or 'latin1' the encoding is set to
// ISO-8859-1. If the 'charset' parameter is set to 'utf-8' the
// encoding is set to UTF-8. A missing content type header is
// interpreted as 'text/plain; charset=utf-8'.
func LoadURL(url string) (*Properties, error) {
return loadAll([]string{url}, UTF8, false)
}
// LoadURLs reads the content of multiple URLs in the given order into a
// Properties struct. If 'ignoreMissing' is true then a 404 status code will
// not be reported as error. See LoadURL for the Content-Type header
// and the encoding.
func LoadURLs(urls []string, ignoreMissing bool) (*Properties, error) {
return loadAll(urls, UTF8, ignoreMissing)
}
// LoadAll reads the content of multiple URLs or files in the given order into a
// Properties struct. If 'ignoreMissing' is true then a 404 status code or missing file will
// not be reported as error. Encoding sets the encoding for files. For the URLs please see
// LoadURL for the Content-Type header and the encoding.
func LoadAll(names []string, enc Encoding, ignoreMissing bool) (*Properties, error) {
return loadAll(names, enc, ignoreMissing)
}
// MustLoadString reads an UTF8 string into a Properties struct and
// panics on error.
func MustLoadString(s string) *Properties {
return must(LoadString(s))
}
// MustLoadFile reads a file into a Properties struct and
// panics on error.
func MustLoadFile(filename string, enc Encoding) *Properties {
return must(LoadFile(filename, enc))
}
// MustLoadFiles reads multiple files in the given order into
// a Properties struct and panics on error. If 'ignoreMissing'
// is true then non-existent files will not be reported as error.
func MustLoadFiles(filenames []string, enc Encoding, ignoreMissing bool) *Properties {
return must(LoadFiles(filenames, enc, ignoreMissing))
}
// MustLoadURL reads the content of a URL into a Properties struct and
// panics on error.
func MustLoadURL(url string) *Properties {
return must(LoadURL(url))
}
// MustLoadURLs reads the content of multiple URLs in the given order into a
// Properties struct and panics on error. If 'ignoreMissing' is true then a 404
// status code will not be reported as error.
func MustLoadURLs(urls []string, ignoreMissing bool) *Properties {
return must(LoadURLs(urls, ignoreMissing))
}
// MustLoadAll reads the content of multiple URLs or files in the given order into a
// Properties struct. If 'ignoreMissing' is true then a 404 status code or missing file will
// not be reported as error. Encoding sets the encoding for files. For the URLs please see
// LoadURL for the Content-Type header and the encoding. It panics on error.
func MustLoadAll(names []string, enc Encoding, ignoreMissing bool) *Properties {
return must(LoadAll(names, enc, ignoreMissing))
}
func loadBuf(buf []byte, enc Encoding) (*Properties, error) {
p, err := parse(convert(buf, enc))
if err != nil {
return nil, err
}
return p, p.check()
}
func loadAll(names []string, enc Encoding, ignoreMissing bool) (*Properties, error) {
result := NewProperties()
for _, name := range names {
n, err := expandName(name)
if err != nil {
return nil, err
}
var p *Properties
if strings.HasPrefix(n, "http://") || strings.HasPrefix(n, "https://") {
p, err = loadURL(n, ignoreMissing)
} else {
p, err = loadFile(n, enc, ignoreMissing)
}
if err != nil {
return nil, err
}
result.Merge(p)
}
return result, result.check()
}
func loadFile(filename string, enc Encoding, ignoreMissing bool) (*Properties, error) {
data, err := ioutil.ReadFile(filename)
if err != nil {
if ignoreMissing && os.IsNotExist(err) {
LogPrintf("properties: %s not found. skipping", filename)
return NewProperties(), nil
}
return nil, err
}
p, err := parse(convert(data, enc))
if err != nil {
return nil, err
}
return p, nil
}
func loadURL(url string, ignoreMissing bool) (*Properties, error) {
resp, err := http.Get(url)
if err != nil {
return nil, fmt.Errorf("properties: error fetching %q. %s", url, err)
}
if resp.StatusCode == 404 && ignoreMissing {
LogPrintf("properties: %s returned %d. skipping", url, resp.StatusCode)
return NewProperties(), nil
}
if resp.StatusCode != 200 {
return nil, fmt.Errorf("properties: %s returned %d", url, resp.StatusCode)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, fmt.Errorf("properties: %s error reading response. %s", url, err)
}
if err = resp.Body.Close(); err != nil {
return nil, fmt.Errorf("properties: %s error reading response. %s", url, err)
}
ct := resp.Header.Get("Content-Type")
var enc Encoding
switch strings.ToLower(ct) {
case "text/plain", "text/plain; charset=iso-8859-1", "text/plain; charset=latin1":
enc = ISO_8859_1
case "", "text/plain; charset=utf-8":
enc = UTF8
default:
return nil, fmt.Errorf("properties: invalid content type %s", ct)
}
p, err := parse(convert(body, enc))
if err != nil {
return nil, err
}
return p, nil
}
func must(p *Properties, err error) *Properties {
if err != nil {
ErrorHandler(err)
}
return p
}
// expandName expands ${ENV_VAR} expressions in a name.
// If the environment variable does not exist then it will be replaced
// with an empty string. Malformed expressions like "${ENV_VAR" will
// be reported as error.
func expandName(name string) (string, error) {
return expand(name, make(map[string]bool), "${", "}", make(map[string]string))
}
// Interprets a byte buffer either as an ISO-8859-1 or UTF-8 encoded string.
// For ISO-8859-1 we can convert each byte straight into a rune since the
// first 256 unicode code points cover ISO-8859-1.
func convert(buf []byte, enc Encoding) string {
switch enc {
case UTF8:
return string(buf)
case ISO_8859_1:
runes := make([]rune, len(buf))
for i, b := range buf {
runes[i] = rune(b)
}
return string(runes)
default:
ErrorHandler(fmt.Errorf("unsupported encoding %v", enc))
}
panic("ErrorHandler should exit")
}