Add html builtin module

internal/builtins/html.go

@@ -0,0 +1,229 @@
+package builtins
+
+import (
+	"io"
+	"strings"
+
+	"github.com/PuerkitoBio/goquery"
+	"go.starlark.net/starlark"
+	"go.starlark.net/starlarkstruct"
+)
+
+var (
+	_ starlark.Iterable  = (*starlarkSelection)(nil)
+	_ starlark.Sliceable = (*starlarkSelection)(nil)
+	_ starlark.Sequence  = (*starlarkSelection)(nil)
+	_ starlark.Value     = (*starlarkSelection)(nil)
+)
+
+var htmlModule = &starlarkstruct.Module{
+	Name: "html",
+	Members: starlark.StringDict{
+		"parse": starlark.NewBuiltin("html.parse", htmlParse),
+	},
+}
+
+func htmlParse(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var val starlark.Value
+	err := starlark.UnpackArgs("html.selection.find", args, kwargs, "from", &val)
+	if err != nil {
+		return nil, err
+	}
+
+	var r io.ReadCloser
+	switch val := val.(type) {
+	case starlark.String:
+		r = io.NopCloser(strings.NewReader(string(val)))
+	case starlark.Bytes:
+		r = io.NopCloser(strings.NewReader(string(val)))
+	case starlarkReader:
+		r = val
+	}
+	defer r.Close()
+
+	doc, err := goquery.NewDocumentFromReader(r)
+	if err != nil {
+		return nil, err
+	}
+
+	return newStarlarkSelection(doc.Selection), nil
+}
+
+type starlarkSelection struct {
+	sel *goquery.Selection
+	*starlarkstruct.Struct
+}
+
+func newStarlarkSelection(sel *goquery.Selection) starlarkSelection {
+	ss := starlarkSelection{sel: sel}
+	ss.Struct = starlarkstruct.FromStringDict(starlark.String("html.selection"), starlark.StringDict{
+		"text":           starlark.NewBuiltin("html.selection.text", ss.text),
+		"html":           starlark.NewBuiltin("html.selection.html", ss.html),
+		"children":       starlark.NewBuiltin("html.selection.children", ss.children),
+		"parent":         starlark.NewBuiltin("html.selection.parent", ss.parent),
+		"find":           starlark.NewBuiltin("html.selection.find", ss.find),
+		"add":            starlark.NewBuiltin("html.selection.add", ss.add),
+		"attr":           starlark.NewBuiltin("html.selection.attr", ss.attr),
+		"has_class":      starlark.NewBuiltin("html.selection.has_class", ss.hasClass),
+		"index_selector": starlark.NewBuiltin("html.selection.index_selector", ss.indexSelector),
+		"and_self":       starlark.NewBuiltin("html.selection.and_self", ss.andSelf),
+		"first":          starlark.NewBuiltin("html.selection.first", ss.first),
+		"last":           starlark.NewBuiltin("html.selection.last", ss.last),
+		"next":           starlark.NewBuiltin("html.selection.last", ss.next),
+		"next_all":       starlark.NewBuiltin("html.selection.next_all", ss.nextAll),
+		"next_until":     starlark.NewBuiltin("html.selection.next_until", ss.nextUntil),
+		"prev":           starlark.NewBuiltin("html.selection.prev", ss.prev),
+		"prev_all":       starlark.NewBuiltin("html.selection.prev_all", ss.prevAll),
+		"prev_until":     starlark.NewBuiltin("html.selection.prev_until", ss.prevUntil),
+	})
+	return ss
+}
+
+func (ss starlarkSelection) Truth() starlark.Bool {
+	return len(ss.sel.Nodes) > 0
+}
+
+func (ss starlarkSelection) Len() int {
+	return ss.sel.Length()
+}
+
+func (ss starlarkSelection) Index(i int) starlark.Value {
+	return newStarlarkSelection(ss.sel.Slice(i, i+1))
+}
+
+func (ss starlarkSelection) Slice(start, end, _ int) starlark.Value {
+	return newStarlarkSelection(ss.sel.Slice(start, end))
+}
+
+func (ss starlarkSelection) Iterate() starlark.Iterator {
+	return newSelectionIterator(ss.sel)
+}
+
+func (ss starlarkSelection) text(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return starlark.String(ss.sel.Text()), nil
+}
+
+func (ss starlarkSelection) html(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	s, err := ss.sel.Html()
+	return starlark.String(s), err
+}
+
+func (ss starlarkSelection) children(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.Children()), nil
+}
+
+func (ss starlarkSelection) parent(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.Parent()), nil
+}
+
+func (ss starlarkSelection) find(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var selector string
+	err := starlark.UnpackArgs("html.selection.find", args, kwargs, "selector", &selector)
+	if err != nil {
+		return nil, err
+	}
+
+	return newStarlarkSelection(ss.sel.Find(selector)), nil
+}
+
+func (ss starlarkSelection) add(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var selector string
+	err := starlark.UnpackArgs("html.selection.add", args, kwargs, "selector", &selector)
+	if err != nil {
+		return nil, err
+	}
+	return newStarlarkSelection(ss.sel.Add(selector)), nil
+}
+
+func (ss starlarkSelection) indexSelector(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var selector string
+	err := starlark.UnpackArgs("html.selection.index_selector", args, kwargs, "selector", &selector)
+	if err != nil {
+		return nil, err
+	}
+	return starlark.MakeInt(ss.sel.IndexSelector(selector)), nil
+}
+
+func (ss starlarkSelection) attr(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var name, def string
+	err := starlark.UnpackArgs("html.selection.find", args, kwargs, "name", &name, "default??", &def)
+	if err != nil {
+		return nil, err
+	}
+	return starlark.String(ss.sel.AttrOr(name, def)), nil
+}
+
+func (ss starlarkSelection) hasClass(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var name string
+	err := starlark.UnpackArgs("html.selection.has_class", args, kwargs, "name", &name)
+	if err != nil {
+		return nil, err
+	}
+	return starlark.Bool(ss.sel.HasClass(name)), nil
+}
+
+func (ss starlarkSelection) andSelf(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.AndSelf()), nil
+}
+
+func (ss starlarkSelection) first(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.First()), nil
+}
+
+func (ss starlarkSelection) last(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.Last()), nil
+}
+
+func (ss starlarkSelection) next(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.Next()), nil
+}
+
+func (ss starlarkSelection) nextAll(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.NextAll()), nil
+}
+
+func (ss starlarkSelection) nextUntil(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var selector string
+	err := starlark.UnpackArgs("html.selection.next_until", args, kwargs, "selector", &selector)
+	if err != nil {
+		return nil, err
+	}
+	return newStarlarkSelection(ss.sel.NextUntil(selector)), nil
+}
+
+func (ss starlarkSelection) prev(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.Prev()), nil
+}
+
+func (ss starlarkSelection) prevAll(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	return newStarlarkSelection(ss.sel.PrevAll()), nil
+}
+
+func (ss starlarkSelection) prevUntil(thread *starlark.Thread, fn *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	var selector string
+	err := starlark.UnpackArgs("html.selection.prev_until", args, kwargs, "selector", &selector)
+	if err != nil {
+		return nil, err
+	}
+	return newStarlarkSelection(ss.sel.PrevUntil(selector)), nil
+}
+
+type starlarkSelectionIterator struct {
+	sel   *goquery.Selection
+	index int
+}
+
+func newSelectionIterator(sel *goquery.Selection) *starlarkSelectionIterator {
+	return &starlarkSelectionIterator{sel: sel}
+}
+
+func (ssi *starlarkSelectionIterator) Next(v *starlark.Value) bool {
+	if ssi.index == ssi.sel.Length() {
+		return false
+	}
+	*v = newStarlarkSelection(ssi.sel.Slice(ssi.index, ssi.index+1))
+	ssi.index++
+	return true
+}
+
+func (ssi *starlarkSelectionIterator) Done() {}

internal/builtins/reader.go

@@ -200,3 +200,16 @@ func (sr starlarkReader) closeReader(thread *starlark.Thread, b *starlark.Builti
 	}
 	return starlark.None, nil
 }
+
+// Read implements the io.ReadCloser interface
+func (sr starlarkReader) Read(b []byte) (int, error) {
+	return sr.br.Read(b)
+}
+
+// Close implements the io.ReadCloser interface
+func (sr starlarkReader) Close() error {
+	if sr.closeFunc != nil {
+		return sr.closeFunc()
+	}
+	return nil
+}

internal/builtins/register.go

@@ -44,5 +44,6 @@ func Register(sd starlark.StringDict, opts *Options) {
 	sd["log"] = logModule(opts.Name)
 	sd["json"] = starlarkjson.Module
 	sd["utils"] = utilsModule
+	sd["html"] = htmlModule
 	sd["register_webhook"] = registerWebhook(opts.Mux, opts.Config, opts.Name)
 }