Add data layer

This includes config changes, collections, posts, some post rendering
funcs, and actual database connection when the server starts up.

postrender.go

@@ -0,0 +1,135 @@
+package writefreely
+
+import (
+	"bytes"
+	"github.com/microcosm-cc/bluemonday"
+	stripmd "github.com/writeas/go-strip-markdown"
+	"github.com/writeas/saturday"
+	"html"
+	"html/template"
+	"regexp"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+var (
+	blockReg        = regexp.MustCompile("<(ul|ol|blockquote)>\n")
+	endBlockReg     = regexp.MustCompile("</([a-z]+)>\n</(ul|ol|blockquote)>")
+	youtubeReg      = regexp.MustCompile("(https?://www.youtube.com/embed/[a-zA-Z0-9\\-_]+)(\\?[^\t\n\f\r \"']+)?")
+	titleElementReg = regexp.MustCompile("</?h[1-6]>")
+	hashtagReg      = regexp.MustCompile(`#([\p{L}\p{M}\d]+)`)
+	markeddownReg   = regexp.MustCompile("<p>(.+)</p>")
+)
+
+func (p *Post) formatContent(c *Collection, isOwner bool) {
+	baseURL := c.CanonicalURL()
+	if isOwner {
+		baseURL = "/" + c.Alias + "/"
+	}
+	newCon := hashtagReg.ReplaceAllFunc([]byte(p.Content), func(b []byte) []byte {
+		// Ensure we only replace "hashtags" that have already been extracted.
+		// `hashtagReg` catches everything, including any hash on the end of a
+		// URL, so we rely on p.Tags as the final word on whether or not to link
+		// a tag.
+		for _, t := range p.Tags {
+			if string(b) == "#"+t {
+				return bytes.Replace(b, []byte("#"+t), []byte("<a href=\""+baseURL+"tag:"+t+"\" class=\"hashtag\"><span>#</span><span class=\"p-category\">"+t+"</span></a>"), -1)
+			}
+		}
+		return b
+	})
+	p.HTMLTitle = template.HTML(applyBasicMarkdown([]byte(p.Title.String)))
+	p.HTMLContent = template.HTML(applyMarkdown([]byte(newCon)))
+	if exc := strings.Index(string(newCon), "<!--more-->"); exc > -1 {
+		p.HTMLExcerpt = template.HTML(applyMarkdown([]byte(newCon[:exc])))
+	}
+}
+
+func (p *PublicPost) formatContent(isOwner bool) {
+	p.Post.formatContent(&p.Collection.Collection, isOwner)
+}
+
+func applyMarkdown(data []byte) string {
+	return applyMarkdownSpecial(data, false)
+}
+
+func applyMarkdownSpecial(data []byte, skipNoFollow bool) string {
+	mdExtensions := 0 |
+		blackfriday.EXTENSION_TABLES |
+		blackfriday.EXTENSION_FENCED_CODE |
+		blackfriday.EXTENSION_AUTOLINK |
+		blackfriday.EXTENSION_STRIKETHROUGH |
+		blackfriday.EXTENSION_SPACE_HEADERS |
+		blackfriday.EXTENSION_AUTO_HEADER_IDS
+	htmlFlags := 0 |
+		blackfriday.HTML_USE_SMARTYPANTS |
+		blackfriday.HTML_SMARTYPANTS_DASHES
+
+	// Generate Markdown
+	md := blackfriday.Markdown([]byte(data), blackfriday.HtmlRenderer(htmlFlags, "", ""), mdExtensions)
+	// Strip out bad HTML
+	policy := getSanitizationPolicy()
+	policy.RequireNoFollowOnLinks(!skipNoFollow)
+	outHTML := string(policy.SanitizeBytes(md))
+	// Strip newlines on certain block elements that render with them
+	outHTML = blockReg.ReplaceAllString(outHTML, "<$1>")
+	outHTML = endBlockReg.ReplaceAllString(outHTML, "</$1></$2>")
+	// Remove all query parameters on YouTube embed links
+	// TODO: make this more specific. Taking the nuclear approach here to strip ?autoplay=1
+	outHTML = youtubeReg.ReplaceAllString(outHTML, "$1")
+
+	return outHTML
+}
+
+func applyBasicMarkdown(data []byte) string {
+	mdExtensions := 0 |
+		blackfriday.EXTENSION_STRIKETHROUGH |
+		blackfriday.EXTENSION_SPACE_HEADERS |
+		blackfriday.EXTENSION_HEADER_IDS
+	htmlFlags := 0 |
+		blackfriday.HTML_SKIP_HTML |
+		blackfriday.HTML_USE_SMARTYPANTS |
+		blackfriday.HTML_SMARTYPANTS_DASHES
+
+	// Generate Markdown
+	md := blackfriday.Markdown([]byte(data), blackfriday.HtmlRenderer(htmlFlags, "", ""), mdExtensions)
+	// Strip out bad HTML
+	policy := bluemonday.UGCPolicy()
+	policy.AllowAttrs("class", "id").Globally()
+	outHTML := string(policy.SanitizeBytes(md))
+	outHTML = markeddownReg.ReplaceAllString(outHTML, "$1")
+	outHTML = strings.TrimRightFunc(outHTML, unicode.IsSpace)
+
+	return outHTML
+}
+
+func postTitle(content, friendlyId string) string {
+	const maxTitleLen = 80
+
+	// Strip HTML tags with bluemonday's StrictPolicy, then unescape the HTML
+	// entities added in by sanitizing the content.
+	content = html.UnescapeString(bluemonday.StrictPolicy().Sanitize(content))
+
+	content = strings.TrimLeftFunc(stripmd.Strip(content), unicode.IsSpace)
+	eol := strings.IndexRune(content, '\n')
+	blankLine := strings.Index(content, "\n\n")
+	if blankLine != -1 && blankLine <= eol && blankLine <= assumedTitleLen {
+		return strings.TrimSpace(content[:blankLine])
+	} else if utf8.RuneCountInString(content) <= maxTitleLen {
+		return content
+	}
+	return friendlyId
+}
+
+func getSanitizationPolicy() *bluemonday.Policy {
+	policy := bluemonday.UGCPolicy()
+	policy.AllowAttrs("src", "style").OnElements("iframe", "video")
+	policy.AllowAttrs("frameborder", "width", "height").Matching(bluemonday.Integer).OnElements("iframe")
+	policy.AllowAttrs("allowfullscreen").OnElements("iframe")
+	policy.AllowAttrs("controls", "loop", "muted", "autoplay").OnElements("video")
+	policy.AllowAttrs("target").OnElements("a")
+	policy.AllowAttrs("style", "class", "id").Globally()
+	policy.AllowURLSchemes("http", "https", "mailto", "xmpp")
+	return policy
+}