Implement table extension

Signed-off-by: Jack Baldry <jack.baldry@grafana.com>

tools/transformer/goldmark/extension/table.go

@@ -0,0 +1,101 @@
+// Package extension implements Goldmark extensions.
+package extension
+
+import (
+	"github.com/yuin/goldmark"
+	gast "github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/extension"
+	"github.com/yuin/goldmark/extension/ast"
+	"github.com/yuin/goldmark/renderer"
+	"github.com/yuin/goldmark/util"
+)
+
+// TableMarkdownRenderer is a renderer.NodeRenderer implementation that
+// renders Table nodes.
+type TableMarkdownRenderer struct {
+	extension.TableConfig
+}
+
+// NewTableMarkdownRenderer returns a new TableMarkdownRenderer.
+func NewTableMarkdownRenderer(opts ...extension.TableOption) renderer.NodeRenderer {
+	r := &TableMarkdownRenderer{
+		TableConfig: extension.NewTableConfig(),
+	}
+	for _, opt := range opts {
+		opt.SetTableOption(&r.TableConfig)
+	}
+	return r
+}
+
+// RegisterFuncs implements renderer.NodeRenderer.RegisterFuncs.
+func (r *TableMarkdownRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
+	reg.Register(ast.KindTable, r.renderTable)
+	reg.Register(ast.KindTableHeader, r.renderTableHeader)
+	reg.Register(ast.KindTableRow, r.renderTableRow)
+	reg.Register(ast.KindTableCell, r.renderTableCell)
+}
+
+func (r *TableMarkdownRenderer) renderTable(w util.BufWriter, source []byte, n gast.Node, entering bool) (gast.WalkStatus, error) {
+	if !entering {
+		_, _ = w.WriteString("\n")
+	}
+
+	return gast.WalkContinue, nil
+}
+
+func (r *TableMarkdownRenderer) renderTableHeader(w util.BufWriter, source []byte, n gast.Node, entering bool) (gast.WalkStatus, error) {
+	if !entering {
+		_, _ = w.WriteString("\n")
+
+		// Add a separator line after the header row.
+		_, _ = w.WriteString("|")
+		for i := 0; i < n.ChildCount(); i++ {
+			_, _ = w.WriteString(" --- |")
+		}
+		_, _ = w.WriteString("\n")
+	}
+
+	return gast.WalkContinue, nil
+}
+
+func (r *TableMarkdownRenderer) renderTableRow(w util.BufWriter, _ []byte, n gast.Node, entering bool) (gast.WalkStatus, error) {
+	if !entering {
+		_, _ = w.WriteString("\n")
+	}
+
+	return gast.WalkContinue, nil
+}
+
+func (r *TableMarkdownRenderer) renderTableCell(w util.BufWriter, _ []byte, n gast.Node, entering bool) (gast.WalkStatus, error) {
+	if entering {
+		_, _ = w.WriteString("| ")
+	} else if n.NextSibling() != nil {
+		_, _ = w.WriteString(" ")
+	} else {
+		_, _ = w.WriteString(" |")
+	}
+
+	return gast.WalkContinue, nil
+}
+
+type table struct {
+	options []extension.TableOption
+}
+
+// Table is an extension that allow you to use GFM tables .
+var Table = &table{
+	options: []extension.TableOption{},
+}
+
+// NewTable returns a new extension with given options.
+func NewTable(opts ...extension.TableOption) goldmark.Extender {
+	return &table{
+		options: opts,
+	}
+}
+
+func (e *table) Extend(m goldmark.Markdown) {
+	m.Renderer().AddOptions(renderer.WithNodeRenderers(
+		util.Prioritized(NewTableMarkdownRenderer(e.options...), 500),
+	))
+}

tools/transformer/main.go

@@ -12,6 +12,7 @@ import (
 	"path/filepath"
 	"regexp"
 
+	"github.com/grafana/killercoda/tools/transformer/goldmark/extension"
 	"github.com/grafana/killercoda/tools/transformer/killercoda"
 	"github.com/yuin/goldmark"
 	"github.com/yuin/goldmark/text"
@@ -91,7 +92,9 @@ func transform(srcFilePath, dstDirPath string) error {
 	md := goldmark.New(goldmark.WithExtensions(&KillercodaExtension{
 		Transformers:        DefaultKillercodaTransformers,
 		AdditionalExtenders: []goldmark.Extender{},
-	}))
+	},
+		extension.Table,
+	))
 
 	root := md.Parser().Parse(text.NewReader(data))
 
@@ -127,7 +130,9 @@ func transform(srcFilePath, dstDirPath string) error {
 			AdditionalExtenders: []goldmark.Extender{
 				&StepTransformer{StartMarker: pageIntroStartMarker, EndMarker: pageIntroEndMarker},
 			},
-		}))
+		},
+			extension.Table,
+		))
 
 		if err := writeFile(md, dstDirPath, "intro.md", data); err != nil {
 			return err
@@ -142,7 +147,9 @@ func transform(srcFilePath, dstDirPath string) error {
 			AdditionalExtenders: []goldmark.Extender{
 				&StepTransformer{StartMarker: pageFinishStartMarker, EndMarker: pageFinishEndMarker},
 			},
-		}))
+		},
+			extension.Table,
+		))
 
 		if err := writeFile(md, dstDirPath, "finish.md", data); err != nil {
 			return err
@@ -167,7 +174,9 @@ func transform(srcFilePath, dstDirPath string) error {
 				AdditionalExtenders: []goldmark.Extender{
 					&StepTransformer{StartMarker: startMarker, EndMarker: endMarker},
 				},
-			}))
+			},
+				extension.Table,
+			))
 
 			if err := writeFile(md, dstDirPath, fmt.Sprintf("step%d.md", i), data); err != nil {
 				errs = errors.Join(errs, err)