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main-extractor.go
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main-extractor.go
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package trafilatura
import (
"strings"
"unicode/utf8"
"github.com/go-shiori/dom"
"github.com/markusmobius/go-trafilatura/internal/etree"
"github.com/markusmobius/go-trafilatura/internal/lru"
"github.com/markusmobius/go-trafilatura/internal/selector"
"golang.org/x/net/html"
)
// handleTitles process head elements (titles).
func handleTitles(element *html.Node, cache *lru.Cache, opts Options) *html.Node {
// In original trafilatura, summary is treated as heading.
// However, in XML, <h1> to <h6> is treated simply as <head>,
// which means heading level is not important in XML. Since
// we work mainly in HTML, we can't simply change the summary
// into heading because heading level is important here. So,
// here we just mark the summary as bold to show that it's an
// important text.
if dom.TagName(element) == "summary" {
element.Data = "b"
}
var title *html.Node
if children := dom.Children(element); len(children) == 0 {
// TODO: maybe needs attention?
// tail := etree.Tail(element)
// if tail != "" && rxWords.MatchString(tail) {
// logWarn(opts, "tail in title, stripping: %s", tail)
// }
// etree.SetTail(element, "")
title = processNode(element, cache, opts)
} else {
title = dom.Clone(element, false)
for _, child := range dom.ChildNodes(element) {
clonedChild := dom.Clone(child, true)
processedChild := handleTextNode(clonedChild, cache, false, false, opts)
if processedChild != nil {
dom.AppendChild(title, processedChild)
} else {
dom.AppendChild(title, clonedChild)
}
child.Data = "done"
}
}
if title != nil && textCharsTest(etree.IterText(title, "")) {
return title
}
return nil
}
// handleFormatting process formatting elements (b, i, etc) found
// outside of paragraphs.
func handleFormatting(element *html.Node, cache *lru.Cache, opts Options) *html.Node {
formatting := processNode(element, cache, opts)
if len(dom.Children(element)) == 0 && formatting == nil {
return nil
}
// Repair orphan elements
parent := element.Parent
if parent == nil {
parent = element.PrevSibling
}
var processedElement *html.Node
if parentTag := dom.TagName(parent); parent == nil ||
(!inMap(parentTag, mapXmlCellTags) &&
!inMap(parentTag, mapXmlHeadTags) &&
!inMap(parentTag, mapXmlHiTags) &&
!inMap(parentTag, mapXmlItemTags) &&
!inMap(parentTag, mapXmlQuoteTags) &&
parentTag != "p") {
processedElement = etree.Element("p")
etree.Append(processedElement, formatting)
} else {
processedElement = formatting
}
return processedElement
}
func addSubElement(newChildElement, subElement, processedSubChild *html.Node) *html.Node {
subChildElement := etree.SubElement(newChildElement, dom.TagName(processedSubChild))
etree.SetText(subChildElement, etree.Text(processedSubChild))
etree.SetTail(subChildElement, etree.Tail(processedSubChild))
subChildElement.Attr = append(subChildElement.Attr, subElement.Attr...)
return subChildElement
}
func processNestedElement(child, newChildElement *html.Node, cache *lru.Cache, opts Options) {
etree.SetText(newChildElement, etree.Text(child))
for _, subElement := range etree.IterDescendants(child) {
if inMap(dom.TagName(subElement), mapXmlListTags) {
processedSubChild := handleLists(subElement, cache, opts)
if processedSubChild != nil {
dom.AppendChild(newChildElement, processedSubChild)
}
} else {
processedSubChild := handleTextNode(subElement, cache, false, false, opts)
if processedSubChild != nil {
addSubElement(newChildElement, subElement, processedSubChild)
}
}
subElement.Data = "done"
}
}
func isTextElement(element *html.Node) bool {
return element != nil && textCharsTest(etree.IterText(element, ""))
}
func defineNewElement(processedElement, originalElement *html.Node) {
if processedElement != nil {
childElement := etree.SubElement(originalElement, dom.TagName(processedElement))
etree.SetText(childElement, etree.Text(processedElement))
etree.SetTail(childElement, etree.Tail(processedElement))
}
}
// handleLists process lists elements including their descendants.
func handleLists(element *html.Node, cache *lru.Cache, opts Options) *html.Node {
var newChildElem *html.Node
processedElement := etree.Element(dom.TagName(element))
if text := strings.TrimSpace(etree.Text(element)); text != "" {
newChildElem = etree.SubElement(processedElement, "li")
etree.SetText(newChildElem, text)
}
for _, child := range etree.IterDescendants(element, listXmlItemTags...) {
newChildElem = dom.CreateElement(dom.TagName(child))
if len(dom.Children(child)) == 0 {
processedChild := processNode(child, cache, opts)
if processedChild != nil {
newText := etree.Text(processedChild)
if tail := strings.TrimSpace(etree.Tail(processedChild)); tail != "" {
newText += " " + tail
}
etree.SetText(newChildElem, newText)
etree.Append(processedElement, newChildElem)
}
} else {
processNestedElement(child, newChildElem, cache, opts)
if tail := etree.Tail(child); strings.TrimSpace(tail) != "" {
var newChildElemChildren []*html.Node
for _, el := range dom.Children(newChildElem) {
if dom.TagName(el) != "done" {
newChildElemChildren = append(newChildElemChildren, el)
}
}
if nNewChildElemChildren := len(newChildElemChildren); nNewChildElemChildren > 0 {
lastSubChild := newChildElemChildren[nNewChildElemChildren-1]
if lastTail := etree.Tail(lastSubChild); strings.TrimSpace(lastTail) == "" {
etree.SetTail(lastSubChild, etree.Tail(child))
} else {
newTail := lastTail + " " + etree.Tail(child)
etree.SetTail(lastSubChild, newTail)
}
}
}
}
if etree.Text(newChildElem) != "" || len(dom.Children(newChildElem)) > 0 {
etree.Append(processedElement, newChildElem)
}
child.Data = "done"
}
element.Data = "done"
// Test if it has children and text. Avoid double tags??
if isTextElement(processedElement) {
return processedElement
}
return nil
}
// isCodeBlockElement check if it is a code element according to common structural markers.
func isCodeBlockElement(element *html.Node) bool {
// Pip
if dom.GetAttribute(element, "lang") != "" || dom.TagName(element) == "code" {
return true
}
// GitHub
parent := element.Parent
if parent != nil && strings.Contains(dom.ClassName(parent), "highlight") {
return true
}
// Highlight.js
code := dom.QuerySelector(element, "code")
if code != nil && len(dom.Children(element)) == 1 {
return true
}
return false
}
// handleCodeBlocks turn element into a properly tagged code block.
func handleCodeBlocks(element *html.Node) *html.Node {
processedElement := dom.Clone(element, true)
for _, child := range etree.Iter(element) {
child.Data = "done"
}
processedElement.Data = "code"
for _, child := range etree.Iter(processedElement) {
child.Attr = nil
}
return processedElement
}
// handleQuotes process quotes elements.
func handleQuotes(element *html.Node, cache *lru.Cache, opts Options) *html.Node {
// Handle code block first
if isCodeBlockElement(element) {
return handleCodeBlocks(element)
}
processedElement := etree.Element(dom.TagName(element))
for _, child := range etree.Iter(element) {
processedChild := processNode(child, cache, opts)
defineNewElement(processedChild, processedElement)
child.Data = "done"
}
if isTextElement(processedElement) {
etree.StripTags(processedElement, listXmlQuoteTags...)
return processedElement
}
return nil
}
// handleOtherElements handle diverse or unknown elements in the scope of relevant tags.
func handleOtherElements(element *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) *html.Node {
// Handle W3Schools Code
tagName := dom.TagName(element)
if tagName == "div" && strings.Contains(dom.ClassName(element), "w3-code") {
return handleCodeBlocks(element)
}
// Delete non potential element
if _, exist := potentialTags[tagName]; !exist {
if tagName != "done" {
logDebug(opts, "discarding element: %s %q", tagName, dom.TextContent(element))
}
return nil
}
// TODO: make a copy and prune it in case it contains sub-elements handled on their own?
if tagName == "div" || tagName == "details" {
processedElement := handleTextNode(element, cache, false, true, opts)
if processedElement != nil && textCharsTest(etree.Text(processedElement)) {
processedElement.Attr = nil
if dom.TagName(processedElement) == "div" {
processedElement.Data = "p"
}
return processedElement
}
}
logDebug(opts, "unexpected element seen: %s %q", tagName, etree.Text(element))
return nil
}
// handleParagraphs process paragraphs (p) elements along with their children, trim and clean the content.
func handleParagraphs(element *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) *html.Node {
// Clear attributes
element.Attr = nil
// Handle paragraph without children
if len(dom.Children(element)) == 0 {
return processNode(element, cache, opts)
}
// Handle with children
var unwantedChildren []*html.Node
processedElements := make(map[*html.Node]struct{})
for _, child := range dom.GetElementsByTagName(element, "*") {
childTag := dom.TagName(child)
// Make sure child is potential element
if _, exist := potentialTags[childTag]; !exist && childTag != "done" {
logDebug(opts, "unexpected in p: %s %q %q", childTag, etree.Text(child), etree.Tail(child))
unwantedChildren = append(unwantedChildren, child)
continue
}
// If necessary remove duplicate child
if opts.Deduplicate && cache != nil && duplicateTest(child, cache, opts) {
unwantedChildren = append(unwantedChildren, child)
continue
}
switch childTag {
case "p": // nested <p>
logWarn(opts, "extra p within p: %s %q %q", childTag, etree.Text(child), etree.Tail(child))
childText := etree.Text(child)
parentText := etree.Text(child.Parent)
if parentText != "" && childText != "" {
etree.SetText(child, " "+etree.Text(child))
}
etree.Strip(child)
case "a": // links
childHref := trim(dom.GetAttribute(child, "href"))
childTarget := trim(dom.GetAttribute(child, "target"))
child.Attr = nil
if childHref != "" {
dom.SetAttribute(child, "href", childHref)
}
if childTarget != "" {
dom.SetAttribute(child, "target", childTarget)
}
}
processedElements[child] = struct{}{}
}
// Remove unwanted child
for i := len(unwantedChildren) - 1; i >= 0; i-- {
etree.Remove(unwantedChildren[i])
}
// Remove empty elements. Do it backward, to make sure all children
// is removed before its parent.
children := dom.GetElementsByTagName(element, "*")
for i := len(children) - 1; i >= 0; i-- {
isEmpty := !textCharsTest(etree.Text(children[i]))
isVoidElement := dom.IsVoidElement(children[i])
if isEmpty && !isVoidElement {
etree.Strip(children[i])
}
}
// Clean trailing line break
lineBreaks := dom.QuerySelectorAll(element, "br,hr")
for i := len(lineBreaks) - 1; i >= 0; i-- {
br := lineBreaks[i]
if br.NextSibling == nil || etree.Tail(br) == "" {
etree.Remove(br)
}
}
// Clone the element to return
processedElement := dom.Clone(element, true)
etree.SetTail(processedElement, etree.Tail(element))
// Mark processed elements as done
for elem := range processedElements {
elem.Data = "done"
}
// Finish
elementText := etree.Text(processedElement)
elementChildren := dom.Children(processedElement)
if len(elementChildren) > 0 || elementText != "" {
return processedElement
}
logDebug(opts, "discarding p-child: %s", trim(etree.ToString(processedElement)))
return nil
}
// handleTable process single table element.
func handleTable(tableElement *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) *html.Node {
newTable := etree.Element(("table"))
newRow := etree.Element("tr")
// Prepare potential tags with div
potentialTagsWithDiv := duplicateMap(potentialTags)
potentialTagsWithDiv["div"] = struct{}{}
// TODO: we are supposed to strip structural elements here, but I'm not so sure.
// Check it again later, I guess.
etree.StripTags(tableElement, "thead", "tbody", "tfoot")
// Explore sub-elements
for _, subElement := range etree.IterDescendants(tableElement) {
subElementTag := dom.TagName(subElement)
if subElementTag == "tr" {
if len(dom.Children(newRow)) > 0 {
etree.Append(newTable, newRow)
newRow = etree.Element("tr")
}
} else if subElementTag == "td" || subElementTag == "th" {
newChildElem := etree.Element(subElementTag)
// Process childless element
if len(dom.Children(subElement)) == 0 {
processedCell := processNode(subElement, cache, opts)
if processedCell != nil {
etree.SetText(newChildElem, etree.Text(processedCell))
etree.SetTail(newChildElem, etree.Tail(processedCell))
}
} else {
// Proceed with iteration, fix for nested elements
etree.SetText(newChildElem, etree.Text(subElement))
etree.SetTail(newChildElem, etree.Tail(subElement))
subElement.Data = "done"
for _, child := range etree.IterDescendants(subElement) {
childTag := dom.TagName(child)
var processedSubChild *html.Node
if inMap(childTag, mapXmlCellTags) || inMap(childTag, mapXmlHiTags) {
processedSubChild = handleTextNode(child, cache, true, false, opts)
} else if inMap(childTag, mapXmlListTags) && opts.Focus == FavorRecall {
processedSubChild = handleLists(child, cache, opts)
if processedSubChild != nil {
etree.Append(newChildElem, dom.Clone(processedSubChild, true))
processedSubChild = nil
}
} else {
processedSubChild = handleTextElem(child, potentialTagsWithDiv, cache, opts)
}
// Add child element to processed_element
defineNewElement(processedSubChild, newChildElem)
child.Data = "done"
}
}
// Add to tree
if etree.Text(newChildElem) != "" || len(dom.Children(newChildElem)) > 0 {
dom.AppendChild(newRow, newChildElem)
}
} else if subElementTag == "table" {
// beware of nested tables
break
}
// Clean up
subElement.Data = "done"
}
// End of processing
if len(dom.Children(newRow)) > 0 {
etree.Append(newTable, newRow)
}
if len(dom.Children(newTable)) > 0 {
return newTable
}
return nil
}
// handleImage process image element and their relevant attributes.
func handleImage(element *html.Node) *html.Node {
processedElement := etree.Element(dom.TagName(element))
// Handle image source
elementSrc := dom.GetAttribute(element, "src")
elementDataSrc := dom.GetAttribute(element, "data-src")
if isImageFile(elementDataSrc) {
dom.SetAttribute(processedElement, "src", elementDataSrc)
} else if isImageFile(elementSrc) {
dom.SetAttribute(processedElement, "src", elementSrc)
} else {
// Take the first corresponding attribute
for _, attr := range element.Attr {
if strings.HasPrefix(attr.Key, "data-src") && isImageFile(attr.Val) {
dom.SetAttribute(processedElement, "src", attr.Val)
break
}
}
}
// Handle additional data
if elementAlt := dom.GetAttribute(element, "alt"); elementAlt != "" {
dom.SetAttribute(processedElement, "alt", elementAlt)
}
if elementTitle := dom.GetAttribute(element, "title"); elementTitle != "" {
dom.SetAttribute(processedElement, "title", elementTitle)
}
// If image doesn't have any attributes or doesn't have any src, return nil
if len(processedElement.Attr) == 0 || dom.GetAttribute(processedElement, "src") == "" {
return nil
}
// Post process the URL
url := dom.GetAttribute(processedElement, "src")
if url != "" && strings.HasPrefix(url, "//") {
url = "http://" + strings.TrimPrefix(url, "//")
dom.SetAttribute(processedElement, "src", url)
}
return processedElement
}
// handleTextElem process text element and determine how to deal with its content.
func handleTextElem(element *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) *html.Node {
tagName := dom.TagName(element)
if inMap(tagName, mapXmlListTags) {
return handleLists(element, cache, opts)
} else if inMap(tagName, mapXmlQuoteTags) || tagName == "code" {
return handleQuotes(element, cache, opts)
} else if inMap(tagName, mapXmlHeadTags) {
return handleTitles(element, cache, opts)
} else if tagName == "p" {
return handleParagraphs(element, potentialTags, cache, opts)
} else if inMap(tagName, mapXmlLbTags) {
if textCharsTest(etree.Tail(element)) {
if processedLb := processNode(element, cache, opts); processedLb != nil {
newElement := etree.Element("p")
etree.SetText(newElement, etree.Tail(processedLb))
return newElement
}
}
} else if inMap(tagName, mapXmlHiTags) || inMap(tagName, mapXmlRefTags) || tagName == "span" {
return handleFormatting(element, cache, opts)
} else if tagName == "table" {
if _, exist := potentialTags["table"]; exist {
return handleTable(element, potentialTags, cache, opts)
}
} else if inMap(tagName, mapXmlGraphicTags) {
if _, exist := potentialTags["img"]; exist {
return handleImage(element)
}
}
return handleOtherElements(element, potentialTags, cache, opts)
}
// recoverWildText Look for all previously unconsidered wild elements, including
// outside of the determined frame and throughout the document to recover potentially
// missing text parts.
func recoverWildText(doc, resultBody *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) {
logInfo(opts, "recovering wild text elements")
var selectorList []string
selectorList = append(selectorList, listXmlQuoteTags...)
selectorList = append(selectorList, "code", "p", "table", `div[class*="w3-code"]`)
if opts.Focus == FavorRecall {
potentialTags = duplicateMap(potentialTags)
potentialTags["div"] = struct{}{}
for _, t := range listXmlLbTags {
potentialTags[t] = struct{}{}
}
selectorList = append(selectorList, "div")
selectorList = append(selectorList, listXmlLbTags...)
selectorList = append(selectorList, listXmlListTags...)
}
// Prune
searchDoc := pruneUnwantedSections(doc, opts)
// Decide if links are preserved
if _, exist := potentialTags["a"]; !exist {
etree.StripTags(searchDoc, "a", "ref", "span")
} else {
etree.StripTags(searchDoc, "span")
}
var processedElems []*html.Node
selectors := strings.Join(selectorList, ", ")
for _, element := range dom.QuerySelectorAll(searchDoc, selectors) {
processedElement := handleTextElem(element, potentialTags, cache, opts)
if processedElement != nil {
processedElems = append(processedElems, processedElement)
}
}
etree.Extend(resultBody, processedElems...)
}
// pruneUnwantedSections is rule-based deletion of targeted document sections.
func pruneUnwantedSections(subTree *html.Node, opts Options) *html.Node {
// Prune the rest
subTree = pruneUnwantedNodes(subTree, selector.OverallDiscardedContent, true)
subTree = pruneUnwantedNodes(subTree, selector.DiscardedPaywall)
// Prune images
if !opts.IncludeImages {
subTree = pruneUnwantedNodes(subTree, selector.DiscardedImage)
}
// Balance precision / recall
if opts.Focus != FavorRecall {
subTree = pruneUnwantedNodes(subTree, selector.DiscardedTeaser)
if opts.Focus == FavorPrecision {
subTree = pruneUnwantedNodes(subTree, selector.PrecisionDiscardedContent)
}
}
// Remove elements by link density
deleteByLinkDensity(subTree, opts, true, "div")
deleteByLinkDensity(subTree, opts, true, listXmlListTags...)
deleteByLinkDensity(subTree, opts, false, "p")
// Also filter fw/head, table and quote elements?
if opts.Focus == FavorPrecision {
// Delete trailing titles
children := dom.Children(subTree)
for i := len(children) - 1; i >= 0; i-- {
if inMap(dom.TagName(children[i]), mapXmlHeadTags) {
children[i].Parent.RemoveChild(children[i])
continue
}
break
}
deleteByLinkDensity(subTree, opts, false, listXmlHeadTags...)
deleteByLinkDensity(subTree, opts, false, listXmlQuoteTags...)
}
return subTree
}
// extractContent find the main content of a page using a set of selectors, then
// extract relevant elements, strip them of unwanted subparts and convert them.
func extractContent(doc *html.Node, cache *lru.Cache, opts Options) (*html.Node, string) {
backupDoc := dom.Clone(doc, true)
resultBody := dom.CreateElement("body")
// Prepare potential tags
potentialTags := duplicateMap(tagCatalog)
if !opts.ExcludeTables {
potentialTags["table"] = struct{}{}
potentialTags["tr"] = struct{}{}
potentialTags["th"] = struct{}{}
potentialTags["td"] = struct{}{}
}
if opts.IncludeImages {
potentialTags["img"] = struct{}{}
}
if opts.IncludeLinks {
potentialTags["a"] = struct{}{}
}
// Iterate each selector rule
for _, query := range selector.Content {
// Capture first node that matched with the rule
subTree := selector.Query(doc, query)
// If no nodes matched, try next selector rule
if subTree == nil {
continue
}
// Prune the subtree
subTree = pruneUnwantedSections(subTree, opts)
// TODO: second pass?
// deleteByLinkDensity(subTree, opts, false, listXmlListTags...)
// Define iteration strategy
_, tableIsPotentialTag := potentialTags["table"]
if tableIsPotentialTag || opts.Focus == FavorPrecision {
tables := etree.Iter(subTree, "table")
for i := len(tables) - 1; i >= 0; i-- {
if linkDensityTestTables(tables[i], opts) {
etree.Remove(tables[i])
}
}
}
// If sub tree now empty, try other selector
if len(dom.Children(subTree)) == 0 {
continue
}
// Check if there are enough <p> with text
var paragraphText string
for _, p := range dom.GetElementsByTagName(doc, "p") {
paragraphText += dom.TextContent(p)
}
factor := 3
if opts.Focus == FavorPrecision {
factor = 1
}
if paragraphText == "" ||
utf8.RuneCountInString(paragraphText) < opts.Config.MinExtractedSize*factor {
potentialTags["div"] = struct{}{}
}
// Polish list of potential tags
if _, exist := potentialTags["a"]; !exist {
etree.StripTags(subTree, "a")
}
if _, exist := potentialTags["span"]; !exist {
etree.StripTags(subTree, "span")
}
// Fetch sub elements
subElements := dom.GetElementsByTagName(subTree, "*")
// Check if all sub elements are line break
subTagTracker := map[string]struct{}{}
for _, e := range subElements {
subTagTracker[dom.TagName(e)] = struct{}{}
}
if _, hasLineBreak := subTagTracker["br"]; len(subTagTracker) == 1 && hasLineBreak {
subElements = []*html.Node{subTree}
}
// Populate result body
var processedElems []*html.Node
for _, elem := range subElements {
processed := handleTextElem(elem, potentialTags, cache, opts)
if processed != nil {
processedElems = append(processedElems, processed)
}
}
etree.Extend(resultBody, processedElems...)
// Remove trailing titles
finalChildren := dom.Children(resultBody)
for i := len(finalChildren) - 1; i >= 0; i-- {
tagName := dom.TagName(finalChildren[i])
if inMap(tagName, mapXmlHeadTags) || inMap(tagName, mapXmlRefTags) {
etree.Remove(finalChildren[i])
continue
}
break
}
// Exit the loop if the result has children
if len(dom.Children(resultBody)) > 1 {
break
}
}
// Try parsing wild <p> elements if nothing found or text too short
tmpText := trim(etree.IterText(resultBody, " "))
tmpTextLength := utf8.RuneCountInString(tmpText)
if len(dom.Children(resultBody)) == 0 || tmpTextLength < opts.Config.MinExtractedSize {
resultBody = dom.CreateElement("body")
recoverWildText(backupDoc, resultBody, potentialTags, cache, opts)
tmpText = trim(etree.IterText(resultBody, " "))
}
// Filter output
etree.StripElements(resultBody, false, "done")
etree.StripTags(resultBody, "div")
return resultBody, tmpText
}
// processCommentsNode process and determine how to deal with comment's content.
func processCommentsNode(elem *html.Node, potentialTags map[string]struct{}, cache *lru.Cache, opts Options) *html.Node {
// Make sure node is one of the potential tags
if _, isPotential := potentialTags[dom.TagName(elem)]; !isPotential {
return nil
}
// Make sure node is not empty and not duplicated
processedNode := handleTextNode(elem, cache, true, false, opts)
if processedNode != nil {
processedNode.Attr = nil
return processedNode
}
return nil
}
// extractComments try and extract comments out of potential sections in the HTML.
func extractComments(doc *html.Node, cache *lru.Cache, opts Options) (*html.Node, string) {
// Prepare final container
commentsBody := etree.Element("body")
// Prepare potential tags
potentialTags := duplicateMap(tagCatalog)
// Process each selector rules
for _, query := range selector.Comments {
// Capture first node that matched with the rule
subTree := selector.Query(doc, query)
// If no nodes matched, try next selector rule
if subTree == nil {
continue
}
// Prune
subTree = pruneUnwantedNodes(subTree, selector.DiscardedComments)
etree.StripTags(subTree, "a", "span")
// Extract comments
var processedElems []*html.Node
for _, elem := range dom.GetElementsByTagName(subTree, "*") {
processed := processCommentsNode(elem, potentialTags, cache, opts)
if processed != nil {
processedElems = append(processedElems, processed)
}
}
etree.Extend(commentsBody, processedElems...)
// Control
if len(dom.Children(commentsBody)) > 0 {
etree.Remove(subTree)
break
}
}
tmpComments := etree.IterText(commentsBody, " ")
if tmpComments != "" {
return commentsBody, tmpComments
}
return nil, ""
}