feed-to-muc/vendor/github.com/mmcdole/gofeed/rss/parser.go
2020-05-14 16:07:09 +02:00

770 lines
16 KiB
Go

package rss
import (
"fmt"
"io"
"strings"
ext "github.com/mmcdole/gofeed/extensions"
"github.com/mmcdole/gofeed/internal/shared"
xpp "github.com/mmcdole/goxpp"
)
// Parser is a RSS Parser
type Parser struct {
base *shared.XMLBase
}
// Parse parses an xml feed into an rss.Feed
func (rp *Parser) Parse(feed io.Reader) (*Feed, error) {
p := xpp.NewXMLPullParser(feed, false, shared.NewReaderLabel)
rp.base = &shared.XMLBase{}
_, err := rp.base.FindRoot(p)
if err != nil {
return nil, err
}
return rp.parseRoot(p)
}
func (rp *Parser) parseRoot(p *xpp.XMLPullParser) (*Feed, error) {
rssErr := p.Expect(xpp.StartTag, "rss")
rdfErr := p.Expect(xpp.StartTag, "rdf")
if rssErr != nil && rdfErr != nil {
return nil, fmt.Errorf("%s or %s", rssErr.Error(), rdfErr.Error())
}
// Items found in feed root
var channel *Feed
var textinput *TextInput
var image *Image
items := []*Item{}
ver := rp.parseVersion(p)
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
// Skip any extensions found in the feed root.
if shared.IsExtension(p) {
p.Skip()
continue
}
name := strings.ToLower(p.Name)
if name == "channel" {
channel, err = rp.parseChannel(p)
if err != nil {
return nil, err
}
} else if name == "item" {
item, err := rp.parseItem(p)
if err != nil {
return nil, err
}
items = append(items, item)
} else if name == "textinput" {
textinput, err = rp.parseTextInput(p)
if err != nil {
return nil, err
}
} else if name == "image" {
image, err = rp.parseImage(p)
if err != nil {
return nil, err
}
} else {
p.Skip()
}
}
}
rssErr = p.Expect(xpp.EndTag, "rss")
rdfErr = p.Expect(xpp.EndTag, "rdf")
if rssErr != nil && rdfErr != nil {
return nil, fmt.Errorf("%s or %s", rssErr.Error(), rdfErr.Error())
}
if channel == nil {
channel = &Feed{}
channel.Items = []*Item{}
}
if len(items) > 0 {
channel.Items = append(channel.Items, items...)
}
if textinput != nil {
channel.TextInput = textinput
}
if image != nil {
channel.Image = image
}
channel.Version = ver
return channel, nil
}
func (rp *Parser) parseChannel(p *xpp.XMLPullParser) (rss *Feed, err error) {
if err = p.Expect(xpp.StartTag, "channel"); err != nil {
return nil, err
}
rss = &Feed{}
rss.Items = []*Item{}
extensions := ext.Extensions{}
categories := []*Category{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if shared.IsExtension(p) {
ext, err := shared.ParseExtension(extensions, p)
if err != nil {
return nil, err
}
extensions = ext
} else if name == "title" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Title = result
} else if name == "description" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Description = result
} else if name == "link" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Link = result
} else if name == "language" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Language = result
} else if name == "copyright" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Copyright = result
} else if name == "managingeditor" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.ManagingEditor = result
} else if name == "webmaster" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.WebMaster = result
} else if name == "pubdate" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.PubDate = result
date, err := shared.ParseDate(result)
if err == nil {
utcDate := date.UTC()
rss.PubDateParsed = &utcDate
}
} else if name == "lastbuilddate" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.LastBuildDate = result
date, err := shared.ParseDate(result)
if err == nil {
utcDate := date.UTC()
rss.LastBuildDateParsed = &utcDate
}
} else if name == "generator" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Generator = result
} else if name == "docs" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Docs = result
} else if name == "ttl" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.TTL = result
} else if name == "rating" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
rss.Rating = result
} else if name == "skiphours" {
result, err := rp.parseSkipHours(p)
if err != nil {
return nil, err
}
rss.SkipHours = result
} else if name == "skipdays" {
result, err := rp.parseSkipDays(p)
if err != nil {
return nil, err
}
rss.SkipDays = result
} else if name == "item" {
result, err := rp.parseItem(p)
if err != nil {
return nil, err
}
rss.Items = append(rss.Items, result)
} else if name == "cloud" {
result, err := rp.parseCloud(p)
if err != nil {
return nil, err
}
rss.Cloud = result
} else if name == "category" {
result, err := rp.parseCategory(p)
if err != nil {
return nil, err
}
categories = append(categories, result)
} else if name == "image" {
result, err := rp.parseImage(p)
if err != nil {
return nil, err
}
rss.Image = result
} else if name == "textinput" {
result, err := rp.parseTextInput(p)
if err != nil {
return nil, err
}
rss.TextInput = result
} else {
// Skip element as it isn't an extension and not
// part of the spec
p.Skip()
}
}
}
if err = p.Expect(xpp.EndTag, "channel"); err != nil {
return nil, err
}
if len(categories) > 0 {
rss.Categories = categories
}
if len(extensions) > 0 {
rss.Extensions = extensions
if itunes, ok := rss.Extensions["itunes"]; ok {
rss.ITunesExt = ext.NewITunesFeedExtension(itunes)
}
if dc, ok := rss.Extensions["dc"]; ok {
rss.DublinCoreExt = ext.NewDublinCoreExtension(dc)
}
}
return rss, nil
}
func (rp *Parser) parseItem(p *xpp.XMLPullParser) (item *Item, err error) {
if err = p.Expect(xpp.StartTag, "item"); err != nil {
return nil, err
}
item = &Item{}
extensions := ext.Extensions{}
categories := []*Category{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if shared.IsExtension(p) {
ext, err := shared.ParseExtension(extensions, p)
if err != nil {
return nil, err
}
item.Extensions = ext
} else if name == "title" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Title = result
} else if name == "description" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Description = result
} else if name == "encoded" {
space := strings.TrimSpace(p.Space)
if prefix, ok := p.Spaces[space]; ok && prefix == "content" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Content = result
}
} else if name == "link" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Link = result
} else if name == "author" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Author = result
} else if name == "comments" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.Comments = result
} else if name == "pubdate" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
item.PubDate = result
date, err := shared.ParseDate(result)
if err == nil {
utcDate := date.UTC()
item.PubDateParsed = &utcDate
}
} else if name == "source" {
result, err := rp.parseSource(p)
if err != nil {
return nil, err
}
item.Source = result
} else if name == "enclosure" {
result, err := rp.parseEnclosure(p)
if err != nil {
return nil, err
}
item.Enclosure = result
} else if name == "guid" {
result, err := rp.parseGUID(p)
if err != nil {
return nil, err
}
item.GUID = result
} else if name == "category" {
result, err := rp.parseCategory(p)
if err != nil {
return nil, err
}
categories = append(categories, result)
} else {
// Skip any elements not part of the item spec
p.Skip()
}
}
}
if len(categories) > 0 {
item.Categories = categories
}
if len(extensions) > 0 {
item.Extensions = extensions
if itunes, ok := item.Extensions["itunes"]; ok {
item.ITunesExt = ext.NewITunesItemExtension(itunes)
}
if dc, ok := item.Extensions["dc"]; ok {
item.DublinCoreExt = ext.NewDublinCoreExtension(dc)
}
}
if err = p.Expect(xpp.EndTag, "item"); err != nil {
return nil, err
}
return item, nil
}
func (rp *Parser) parseSource(p *xpp.XMLPullParser) (source *Source, err error) {
if err = p.Expect(xpp.StartTag, "source"); err != nil {
return nil, err
}
source = &Source{}
source.URL = p.Attribute("url")
result, err := shared.ParseText(p)
if err != nil {
return source, err
}
source.Title = result
if err = p.Expect(xpp.EndTag, "source"); err != nil {
return nil, err
}
return source, nil
}
func (rp *Parser) parseEnclosure(p *xpp.XMLPullParser) (enclosure *Enclosure, err error) {
if err = p.Expect(xpp.StartTag, "enclosure"); err != nil {
return nil, err
}
enclosure = &Enclosure{}
enclosure.URL = p.Attribute("url")
enclosure.Length = p.Attribute("length")
enclosure.Type = p.Attribute("type")
// Ignore any enclosure text
_, err = p.NextText()
if err != nil {
return enclosure, err
}
if err = p.Expect(xpp.EndTag, "enclosure"); err != nil {
return nil, err
}
return enclosure, nil
}
func (rp *Parser) parseImage(p *xpp.XMLPullParser) (image *Image, err error) {
if err = p.Expect(xpp.StartTag, "image"); err != nil {
return nil, err
}
image = &Image{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return image, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if name == "url" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.URL = result
} else if name == "title" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.Title = result
} else if name == "link" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.Link = result
} else if name == "width" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.Width = result
} else if name == "height" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.Height = result
} else if name == "description" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
image.Description = result
} else {
p.Skip()
}
}
}
if err = p.Expect(xpp.EndTag, "image"); err != nil {
return nil, err
}
return image, nil
}
func (rp *Parser) parseGUID(p *xpp.XMLPullParser) (guid *GUID, err error) {
if err = p.Expect(xpp.StartTag, "guid"); err != nil {
return nil, err
}
guid = &GUID{}
guid.IsPermalink = p.Attribute("isPermalink")
result, err := shared.ParseText(p)
if err != nil {
return
}
guid.Value = result
if err = p.Expect(xpp.EndTag, "guid"); err != nil {
return nil, err
}
return guid, nil
}
func (rp *Parser) parseCategory(p *xpp.XMLPullParser) (cat *Category, err error) {
if err = p.Expect(xpp.StartTag, "category"); err != nil {
return nil, err
}
cat = &Category{}
cat.Domain = p.Attribute("domain")
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
cat.Value = result
if err = p.Expect(xpp.EndTag, "category"); err != nil {
return nil, err
}
return cat, nil
}
func (rp *Parser) parseTextInput(p *xpp.XMLPullParser) (*TextInput, error) {
if err := p.Expect(xpp.StartTag, "textinput"); err != nil {
return nil, err
}
ti := &TextInput{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if name == "title" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
ti.Title = result
} else if name == "description" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
ti.Description = result
} else if name == "name" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
ti.Name = result
} else if name == "link" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
ti.Link = result
} else {
p.Skip()
}
}
}
if err := p.Expect(xpp.EndTag, "textinput"); err != nil {
return nil, err
}
return ti, nil
}
func (rp *Parser) parseSkipHours(p *xpp.XMLPullParser) ([]string, error) {
if err := p.Expect(xpp.StartTag, "skiphours"); err != nil {
return nil, err
}
hours := []string{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if name == "hour" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
hours = append(hours, result)
} else {
p.Skip()
}
}
}
if err := p.Expect(xpp.EndTag, "skiphours"); err != nil {
return nil, err
}
return hours, nil
}
func (rp *Parser) parseSkipDays(p *xpp.XMLPullParser) ([]string, error) {
if err := p.Expect(xpp.StartTag, "skipdays"); err != nil {
return nil, err
}
days := []string{}
for {
tok, err := rp.base.NextTag(p)
if err != nil {
return nil, err
}
if tok == xpp.EndTag {
break
}
if tok == xpp.StartTag {
name := strings.ToLower(p.Name)
if name == "day" {
result, err := shared.ParseText(p)
if err != nil {
return nil, err
}
days = append(days, result)
} else {
p.Skip()
}
}
}
if err := p.Expect(xpp.EndTag, "skipdays"); err != nil {
return nil, err
}
return days, nil
}
func (rp *Parser) parseCloud(p *xpp.XMLPullParser) (*Cloud, error) {
if err := p.Expect(xpp.StartTag, "cloud"); err != nil {
return nil, err
}
cloud := &Cloud{}
cloud.Domain = p.Attribute("domain")
cloud.Port = p.Attribute("port")
cloud.Path = p.Attribute("path")
cloud.RegisterProcedure = p.Attribute("registerProcedure")
cloud.Protocol = p.Attribute("protocol")
rp.base.NextTag(p)
if err := p.Expect(xpp.EndTag, "cloud"); err != nil {
return nil, err
}
return cloud, nil
}
func (rp *Parser) parseVersion(p *xpp.XMLPullParser) (ver string) {
name := strings.ToLower(p.Name)
if name == "rss" {
ver = p.Attribute("version")
} else if name == "rdf" {
ns := p.Attribute("xmlns")
if ns == "http://channel.netscape.com/rdf/simple/0.9/" ||
ns == "http://my.netscape.com/rdf/simple/0.9/" {
ver = "0.9"
} else if ns == "http://purl.org/rss/1.0/" {
ver = "1.0"
}
}
return
}