hugo/helpers/general.go
Anthony Fok 563a6302a0 Very experimental support for mmark
Either name the content files as `*.mmark`,
or add `markup = "mmark"` in the front matter
of your `*.md` content files.
2015-05-08 22:05:41 -04:00

412 lines
9.6 KiB
Go

// Copyright © 2014 Steve Francia <spf@spf13.com>.
//
// Licensed under the Simple Public 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://opensource.org/licenses/Simple-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 helpers
import (
"bytes"
"crypto/md5"
"encoding/hex"
"errors"
"fmt"
"io"
"net"
"path/filepath"
"reflect"
"strings"
"sync"
"github.com/spf13/cast"
bp "github.com/spf13/hugo/bufferpool"
jww "github.com/spf13/jwalterweatherman"
"github.com/spf13/viper"
)
// Filepath separator defined by os.Separator.
const FilePathSeparator = string(filepath.Separator)
// FindAvailablePort returns an available and valid TCP port.
func FindAvailablePort() (*net.TCPAddr, error) {
l, err := net.Listen("tcp", ":0")
if err == nil {
defer l.Close()
addr := l.Addr()
if a, ok := addr.(*net.TCPAddr); ok {
return a, nil
}
return nil, fmt.Errorf("Unable to obtain a valid tcp port. %v", addr)
}
return nil, err
}
// InStringArray checks if a string is an element of a slice of strings
// and returns a boolean value.
func InStringArray(arr []string, el string) bool {
for _, v := range arr {
if v == el {
return true
}
}
return false
}
// GuessType attempts to guess the type of file from a given string.
func GuessType(in string) string {
switch strings.ToLower(in) {
case "md", "markdown", "mdown":
return "markdown"
case "asciidoc", "adoc", "ad":
return "asciidoc"
case "mmark":
return "mmark"
case "rst":
return "rst"
case "html", "htm":
return "html"
}
return "unknown"
}
// ReaderToBytes takes an io.Reader argument, reads from it
// and returns bytes.
func ReaderToBytes(lines io.Reader) []byte {
if lines == nil {
return []byte{}
}
b := bp.GetBuffer()
defer bp.PutBuffer(b)
b.ReadFrom(lines)
bc := make([]byte, b.Len(), b.Len())
copy(bc, b.Bytes())
return bc
}
// ReaderToString is the same as ReaderToBytes, but returns a string.
func ReaderToString(lines io.Reader) string {
if lines == nil {
return ""
}
b := bp.GetBuffer()
defer bp.PutBuffer(b)
b.ReadFrom(lines)
return b.String()
}
// StringToReader does the opposite of ReaderToString.
func StringToReader(in string) io.Reader {
return strings.NewReader(in)
}
// BytesToReader does the opposite of ReaderToBytes.
func BytesToReader(in []byte) io.Reader {
return bytes.NewReader(in)
}
// ReaderContains reports whether subslice is within r.
func ReaderContains(r io.Reader, subslice []byte) bool {
if r == nil || len(subslice) == 0 {
return false
}
bufflen := len(subslice) * 4
halflen := bufflen / 2
buff := make([]byte, bufflen)
var err error
var n, i int
for {
i++
if i == 1 {
n, err = io.ReadAtLeast(r, buff[:halflen], halflen)
} else {
if i != 2 {
// shift left to catch overlapping matches
copy(buff[:], buff[halflen:])
}
n, err = io.ReadAtLeast(r, buff[halflen:], halflen)
}
if n > 0 && bytes.Contains(buff, subslice) {
return true
}
if err != nil {
break
}
}
return false
}
// ThemeSet checks whether a theme is in use or not.
func ThemeSet() bool {
return viper.GetString("theme") != ""
}
// DistinctErrorLogger ignores duplicate log statements.
type DistinctErrorLogger struct {
sync.RWMutex
m map[string]bool
}
// Printf will ERROR log the string returned from fmt.Sprintf given the arguments,
// but not if it has been logged before.
func (l *DistinctErrorLogger) Printf(format string, v ...interface{}) {
logStatement := fmt.Sprintf(format, v...)
l.RLock()
if l.m[logStatement] {
l.RUnlock()
return
}
l.RUnlock()
l.Lock()
if !l.m[logStatement] {
jww.ERROR.Print(logStatement)
l.m[logStatement] = true
}
l.Unlock()
}
// NewDistinctErrorLogger creates a new DistinctErrorLogger
func NewDistinctErrorLogger() *DistinctErrorLogger {
return &DistinctErrorLogger{m: make(map[string]bool)}
}
// Avoid spamming the logs with errors
var deprecatedLogger = NewDistinctErrorLogger()
// Deprecated logs ERROR logs about a deprecation, but only once for a given set of arguments' values.
func Deprecated(object, item, alternative string) {
deprecatedLogger.Printf("%s's %s is deprecated and will be removed in Hugo %s. Use %s instead.", object, item, NextHugoReleaseVersion(), alternative)
}
// SliceToLower goes through the source slice and lowers all values.
func SliceToLower(s []string) []string {
if s == nil {
return nil
}
l := make([]string, len(s))
for i, v := range s {
l[i] = strings.ToLower(v)
}
return l
}
// Md5String takes a string and returns its MD5 hash.
func Md5String(f string) string {
h := md5.New()
h.Write([]byte(f))
return hex.EncodeToString(h.Sum([]byte{}))
}
// Seq creates a sequence of integers.
// It's named and used as GNU's seq.
// Examples:
// 3 => 1, 2, 3
// 1 2 4 => 1, 3
// -3 => -1, -2, -3
// 1 4 => 1, 2, 3, 4
// 1 -2 => 1, 0, -1, -2
func Seq(args ...interface{}) ([]int, error) {
if len(args) < 1 || len(args) > 3 {
return nil, errors.New("Seq, invalid number of args: 'first' 'increment' (optional) 'last' (optional)")
}
intArgs := cast.ToIntSlice(args)
if len(intArgs) < 1 || len(intArgs) > 3 {
return nil, errors.New("Invalid argument(s) to Seq")
}
var inc = 1
var last int
var first = intArgs[0]
if len(intArgs) == 1 {
last = first
if last == 0 {
return []int{}, nil
} else if last > 0 {
first = 1
} else {
first = -1
inc = -1
}
} else if len(intArgs) == 2 {
last = intArgs[1]
if last < first {
inc = -1
}
} else {
inc = intArgs[1]
last = intArgs[2]
if inc == 0 {
return nil, errors.New("'increment' must not be 0")
}
if first < last && inc < 0 {
return nil, errors.New("'increment' must be > 0")
}
if first > last && inc > 0 {
return nil, errors.New("'increment' must be < 0")
}
}
// sanity check
if last < -100000 {
return nil, errors.New("size of result exeeds limit")
}
size := int(((last - first) / inc) + 1)
// sanity check
if size <= 0 || size > 2000 {
return nil, errors.New("size of result exeeds limit")
}
seq := make([]int, size)
val := first
for i := 0; ; i++ {
seq[i] = val
val += inc
if (inc < 0 && val < last) || (inc > 0 && val > last) {
break
}
}
return seq, nil
}
// DoArithmetic performs arithmetic operations (+,-,*,/) using reflection to
// determine the type of the two terms.
func DoArithmetic(a, b interface{}, op rune) (interface{}, error) {
av := reflect.ValueOf(a)
bv := reflect.ValueOf(b)
var ai, bi int64
var af, bf float64
var au, bu uint64
switch av.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
ai = av.Int()
switch bv.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
bi = bv.Int()
case reflect.Float32, reflect.Float64:
af = float64(ai) // may overflow
ai = 0
bf = bv.Float()
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
bu = bv.Uint()
if ai >= 0 {
au = uint64(ai)
ai = 0
} else {
bi = int64(bu) // may overflow
bu = 0
}
default:
return nil, errors.New("Can't apply the operator to the values")
}
case reflect.Float32, reflect.Float64:
af = av.Float()
switch bv.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
bf = float64(bv.Int()) // may overflow
case reflect.Float32, reflect.Float64:
bf = bv.Float()
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
bf = float64(bv.Uint()) // may overflow
default:
return nil, errors.New("Can't apply the operator to the values")
}
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
au = av.Uint()
switch bv.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
bi = bv.Int()
if bi >= 0 {
bu = uint64(bi)
bi = 0
} else {
ai = int64(au) // may overflow
au = 0
}
case reflect.Float32, reflect.Float64:
af = float64(au) // may overflow
au = 0
bf = bv.Float()
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
bu = bv.Uint()
default:
return nil, errors.New("Can't apply the operator to the values")
}
case reflect.String:
as := av.String()
if bv.Kind() == reflect.String && op == '+' {
bs := bv.String()
return as + bs, nil
}
return nil, errors.New("Can't apply the operator to the values")
default:
return nil, errors.New("Can't apply the operator to the values")
}
switch op {
case '+':
if ai != 0 || bi != 0 {
return ai + bi, nil
} else if af != 0 || bf != 0 {
return af + bf, nil
} else if au != 0 || bu != 0 {
return au + bu, nil
} else {
return 0, nil
}
case '-':
if ai != 0 || bi != 0 {
return ai - bi, nil
} else if af != 0 || bf != 0 {
return af - bf, nil
} else if au != 0 || bu != 0 {
return au - bu, nil
} else {
return 0, nil
}
case '*':
if ai != 0 || bi != 0 {
return ai * bi, nil
} else if af != 0 || bf != 0 {
return af * bf, nil
} else if au != 0 || bu != 0 {
return au * bu, nil
} else {
return 0, nil
}
case '/':
if bi != 0 {
return ai / bi, nil
} else if bf != 0 {
return af / bf, nil
} else if bu != 0 {
return au / bu, nil
} else {
return nil, errors.New("Can't divide the value by 0")
}
default:
return nil, errors.New("There is no such an operation")
}
}