package main
import (
"bufio"
"bytes"
"fmt"
"html/template"
"io"
"io/ioutil"
"os"
"regexp"
"strings"
"github.com/microcosm-cc/bluemonday"
"github.com/russross/blackfriday"
yaml "gopkg.in/yaml.v2"
)
const delimiter = "---"
type post struct {
Title string
Published bool
Description string
Tags []string
CoverImage string
Series string
PostBody template.HTML
}
type index struct {
Pages []Page
}
type Page struct {
FileName string
Title string
}
var indexTempl = `
shindakun's dev site
`
var postTempl = `
{{.Title}}
{{.Title}}
{{.PostBody}}
`
func getContentsOf(r io.Reader) ([]byte, error) {
b, err := ioutil.ReadAll(r)
if err != nil {
return nil, err
}
return b, nil
}
func parseFrontMatter(b []byte) (map[string]interface{}, error) {
fm := make(map[string]interface{})
err := yaml.Unmarshal(b, &fm)
if err != nil {
msg := fmt.Sprintf("error: %v\ninput:\n%s", err, b)
return nil, fmt.Errorf(msg)
}
return fm, nil
}
func splitData(fm []byte) ([][]byte, error) {
b := bytes.Split(fm, []byte(delimiter))
if len(b) < 3 || len(b[0]) != 0 {
return nil, fmt.Errorf("Front matter is damaged")
}
return b, nil
}
// makePost creates the post struct, returns that and the template HTML
func makePost(fm map[string]interface{}, contents []byte, s [][]byte) (*template.Template, *post) {
post := &post{}
titleIntf, ok := fm["title"]
if ok {
title, ok := titleIntf.(string)
if ok {
post.Title = title
} else {
post.Title = ""
}
} else {
post.Title = ""
}
pubIntf, ok := fm["published"]
if ok {
published, ok := pubIntf.(bool)
if ok {
post.Published = published
} else {
post.Published = false
}
} else {
post.Published = false
}
descIntf, ok := fm["description"]
if ok {
description, ok := descIntf.(string)
if ok {
post.Description = description
} else {
post.Description = ""
}
} else {
post.Description = ""
}
tagsIntf, ok := fm["tags"]
if ok {
tags, ok := tagsIntf.(string)
if ok {
post.Tags = strings.Split(tags, ", ")
} else {
post.Tags = []string{}
}
} else {
post.Tags = []string{}
}
covIntf, ok := fm["cover_image"]
if ok {
coverImage, ok := covIntf.(string)
if ok {
post.CoverImage = coverImage
} else {
post.CoverImage = ""
}
} else {
post.CoverImage = ""
}
seriesIntf, ok := fm["series"]
if ok {
series, ok := seriesIntf.(string)
if ok {
post.Series = series
} else {
post.Series = ""
}
} else {
post.Series = ""
}
pBody := contents[len(s[1])+(len(delimiter)*2):]
out := blackfriday.Run(pBody)
bm := bluemonday.UGCPolicy()
bm.AllowAttrs("class").Matching(regexp.MustCompile("^language-[a-zA-Z0-9]+$")).OnElements("code")
post.PostBody = template.HTML(bm.SanitizeBytes(out))
tm := template.Must(template.New("post").Parse(postTempl))
return tm, post
}
func writeIndex(idx index) {
indexFile, err := os.Create("index.html")
if err != nil {
panic(err)
}
defer indexFile.Close()
buffer := bufio.NewWriter(indexFile)
tm := template.Must(template.New("index").Parse(indexTempl))
err = tm.Execute(buffer, idx)
if err != nil {
panic(err)
}
buffer.Flush()
}
func main() {
var idx index
dir, err := ioutil.ReadDir(".")
if err != nil {
panic(err)
}
for _, file := range dir {
if fileName := file.Name(); strings.HasSuffix(fileName, ".md") {
openedFile, err := os.Open(fileName)
if err != nil {
panic(err)
}
contents, err := getContentsOf(openedFile)
if err != nil {
panic(err)
}
s, err := splitData(contents)
if err != nil {
panic(err)
}
fm, err := parseFrontMatter(s[1])
if err != nil {
msg := fmt.Sprintf("error: %v\ninput:\n%s", err, s[1])
panic(msg)
}
template, post := makePost(fm, contents, s)
trimmedName := strings.TrimSuffix(fileName, ".md")
outputFile, err := os.Create(trimmedName + ".html")
if err != nil {
panic(err)
}
defer outputFile.Close()
buffer := bufio.NewWriter(outputFile)
err = template.Execute(buffer, post)
if err != nil {
panic(err)
}
buffer.Flush()
indexLinks := Page{
FileName: trimmedName + ".html",
Title: post.Title,
}
idx.Pages = append(idx.Pages, indexLinks)
}
}
writeIndex(idx)
}