appview/pages: markup: add @ user-mention parsing in markdown #736

+7 -1

appview/pages/markup/markdown.go

··· 50 50 Files fs.FS 51 51 } 52 52 53 53 - func (rctx *RenderContext) RenderMarkdown(source string) string { 53 53 + func NewMarkdown() goldmark.Markdown { 54 54 md := goldmark.New( 55 55 goldmark.WithExtensions( 56 56 extension.GFM, ··· 66 66 ), 67 67 treeblood.MathML(), 68 68 callout.CalloutExtention, 69 69 + AtExt, 69 70 ), 70 71 goldmark.WithParserOptions( 71 72 parser.WithAutoHeadingID(), 72 73 ), 73 74 goldmark.WithRendererOptions(html.WithUnsafe()), 74 75 ) 76 76 + return md 77 77 + } 78 78 + 79 79 + func (rctx *RenderContext) RenderMarkdown(source string) string { 80 80 + md := NewMarkdown() 75 81 76 82 if rctx != nil { 77 83 var transformers []util.PrioritizedValue

+135

appview/pages/markup/markdown_at_extension.go

··· 1 1 + // heavily inspired by: https://github.com/kaleocheng/goldmark-extensions 2 2 + 3 3 + package markup 4 4 + 5 5 + import ( 6 6 + "regexp" 7 7 + 8 8 + "github.com/yuin/goldmark" 9 9 + "github.com/yuin/goldmark/ast" 10 10 + "github.com/yuin/goldmark/parser" 11 11 + "github.com/yuin/goldmark/renderer" 12 12 + "github.com/yuin/goldmark/renderer/html" 13 13 + "github.com/yuin/goldmark/text" 14 14 + "github.com/yuin/goldmark/util" 15 15 + ) 16 16 + 17 17 + // An AtNode struct represents an AtNode 18 18 + type AtNode struct { 19 19 + handle string 20 20 + ast.BaseInline 21 21 + } 22 22 + 23 23 + var _ ast.Node = &AtNode{} 24 24 + 25 25 + // Dump implements Node.Dump. 26 26 + func (n *AtNode) Dump(source []byte, level int) { 27 27 + ast.DumpHelper(n, source, level, nil, nil) 28 28 + } 29 29 + 30 30 + // KindAt is a NodeKind of the At node. 31 31 + var KindAt = ast.NewNodeKind("At") 32 32 + 33 33 + // Kind implements Node.Kind. 34 34 + func (n *AtNode) Kind() ast.NodeKind { 35 35 + return KindAt 36 36 + } 37 37 + 38 38 + var atRegexp = regexp.MustCompile(`(^|\s|\()(@)([a-zA-Z0-9.-]+)(\b)`) 39 39 + 40 40 + type atParser struct{} 41 41 + 42 42 + // NewAtParser return a new InlineParser that parses 43 43 + // at expressions. 44 44 + func NewAtParser() parser.InlineParser { 45 45 + return &atParser{} 46 46 + } 47 47 + 48 48 + func (s *atParser) Trigger() []byte { 49 49 + return []byte{'@'} 50 50 + } 51 51 + 52 52 + func (s *atParser) Parse(parent ast.Node, block text.Reader, pc parser.Context) ast.Node { 53 53 + line, segment := block.PeekLine() 54 54 + m := atRegexp.FindSubmatchIndex(line) 55 55 + if m == nil { 56 56 + return nil 57 57 + } 58 58 + atSegment := text.NewSegment(segment.Start, segment.Start+m[1]) 59 59 + block.Advance(m[1]) 60 60 + node := &AtNode{} 61 61 + node.AppendChild(node, ast.NewTextSegment(atSegment)) 62 62 + node.handle = string(atSegment.Value(block.Source())[1:]) 63 63 + return node 64 64 + } 65 65 + 66 66 + // atHtmlRenderer is a renderer.NodeRenderer implementation that 67 67 + // renders At nodes. 68 68 + type atHtmlRenderer struct { 69 69 + html.Config 70 70 + } 71 71 + 72 72 + // NewAtHTMLRenderer returns a new AtHTMLRenderer. 73 73 + func NewAtHTMLRenderer(opts ...html.Option) renderer.NodeRenderer { 74 74 + r := &atHtmlRenderer{ 75 75 + Config: html.NewConfig(), 76 76 + } 77 77 + for _, opt := range opts { 78 78 + opt.SetHTMLOption(&r.Config) 79 79 + } 80 80 + return r 81 81 + } 82 82 + 83 83 + // RegisterFuncs implements renderer.NodeRenderer.RegisterFuncs. 84 84 + func (r *atHtmlRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) { 85 85 + reg.Register(KindAt, r.renderAt) 86 86 + } 87 87 + 88 88 + func (r *atHtmlRenderer) renderAt(w util.BufWriter, source []byte, n ast.Node, entering bool) (ast.WalkStatus, error) { 89 89 + if entering { 90 90 + w.WriteString(`<a href="/@`) 91 91 + w.WriteString(n.(*AtNode).handle) 92 92 + w.WriteString(`" class="mention">`) 93 93 + } else { 94 94 + w.WriteString("</a>") 95 95 + } 96 96 + return ast.WalkContinue, nil 97 97 + } 98 98 + 99 99 + type atExt struct{} 100 100 + 101 101 + // At is an extension that allow you to use at expression like '@user.bsky.social' . 102 102 + var AtExt = &atExt{} 103 103 + 104 104 + func (e *atExt) Extend(m goldmark.Markdown) { 105 105 + m.Parser().AddOptions(parser.WithInlineParsers( 106 106 + util.Prioritized(NewAtParser(), 500), 107 107 + )) 108 108 + m.Renderer().AddOptions(renderer.WithNodeRenderers( 109 109 + util.Prioritized(NewAtHTMLRenderer(), 500), 110 110 + )) 111 111 + } 112 112 + 113 113 + // FindUserMentions returns Set of user handles from given markup soruce. 114 114 + // It doesn't guarntee unique DIDs 115 115 + func FindUserMentions(source string) []string { 116 116 + var ( 117 117 + mentions []string 118 118 + mentionsSet = make(map[string]struct{}) 119 119 + md = NewMarkdown() 120 120 + sourceBytes = []byte(source) 121 121 + root = md.Parser().Parse(text.NewReader(sourceBytes)) 122 122 + ) 123 123 + ast.Walk(root, func(n ast.Node, entering bool) (ast.WalkStatus, error) { 124 124 + if entering && n.Kind() == KindAt { 125 125 + handle := n.(*AtNode).handle 126 126 + mentionsSet[handle] = struct{}{} 127 127 + return ast.WalkSkipChildren, nil 128 128 + } 129 129 + return ast.WalkContinue, nil 130 130 + }) 131 131 + for handle := range mentionsSet { 132 132 + mentions = append(mentions, handle) 133 133 + } 134 134 + return mentions 135 135 + }

+3

appview/pages/markup/sanitizer.go

··· 77 77 policy.AllowAttrs("class").Matching(regexp.MustCompile(`heading`)).OnElements("h1", "h2", "h3", "h4", "h5", "h6", "h7", "h8") 78 78 policy.AllowAttrs("class").Matching(regexp.MustCompile(strings.Join(slices.Collect(maps.Values(chroma.StandardTypes)), "|"))).OnElements("span") 79 79 80 80 + // at-mentions 81 81 + policy.AllowAttrs("class").Matching(regexp.MustCompile(`mention`)).OnElements("a") 82 82 + 80 83 // centering content 81 84 policy.AllowElements("center") 82 85

+4

input.css

··· 161 161 @apply no-underline; 162 162 } 163 163 164 164 + .prose a.mention { 165 165 + @apply no-underline hover:underline; 166 166 + } 167 167 + 164 168 .prose li { 165 169 @apply my-0 py-0; 166 170 }