Merge pull request 'Implement Parsing of Multiple Articles on one Page' (#5) from multiple-articles-2 into master

Reviewed-on: #5

feed/feed.go

@@ -1,13 +1,16 @@
 package feed
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
+	"path"
 	"strings"
 	"time"
 
 	"golang.org/x/net/html"
+	"golang.org/x/net/html/atom"
 )
 
 const feedfmtopen = `<?xml version="1.0" encoding="utf-8"?>
@@ -47,6 +50,14 @@ type FeedItem struct {
     RawText     string
 }
 
+type SitePage struct {
+    Url     string
+    Title   string
+    Root    *html.Node
+    Errors  []error
+    ErrStr  string
+}
+
 func fetchPage(url string) (string, error) {
     resp, err := http.Get(url)
     if err != nil {
@@ -85,7 +96,7 @@ func parseTime(timestr string) (time.Time, error) {
             return pagetime, err
         }
     }
-    return pagetime, fmt.Errorf("Error parsing time: invalid format")
+    return pagetime, fmt.Errorf("%s is in an invalid format", timestr)
 }
 
 func getHtmlElement(doc *html.Node, tag string) (*html.Node, error) {
@@ -107,29 +118,72 @@ func getHtmlElement(doc *html.Node, tag string) (*html.Node, error) {
     return element, nil
 }
 
-func (f *FeedItem) ParseContent(content string) error {
-    doc, err := html.Parse(strings.NewReader(content))
-    if err != nil {
-        return fmt.Errorf("Error parsing HTML: %w", err)
+func getAllElements(doc *html.Node, tag string) ([]*html.Node, error) {
+    var f func(*html.Node, string)
+    elements := make([]*html.Node, 0)
+    f = func(n *html.Node, s string) {
+        if n.Type == html.ElementNode && n.Data == s{
+            elements = append(elements, n)
+            return
         }
-    earticle, err := getHtmlElement(doc, "article")
-    if err != nil {
-        return err
+        for c := n.FirstChild; c != nil; c = c.NextSibling {
+            f(c, tag)
         }
-    etitle, err := getHtmlElement(doc, "title")
-    if err != nil {
-        f.Title = ""
-    } else {
-        f.Title = etitle.FirstChild.Data
+    }
+    f(doc, tag)
+    if len(elements) == 0 {
+        return nil, fmt.Errorf("no &lt;%s&gt; element found", tag)
+    }
+    return elements, nil
 }
 
+func getTitleAndUrl(article *html.Node) (string, string, error) {
+    var title string
+    var url string
+    var header *html.Node
+    h1s, _ := getAllElements(article, "h1")
+    h2s, _ := getAllElements(article, "h2")
+    h3s, _ := getAllElements(article, "h3")
+    if len(h1s) > 0 {
+        header = h1s[0]
+    } else if len(h2s) > 0 {
+        header = h2s[0]
+    } else if len(h3s) > 0 {
+        header = h3s[0]
+    }
+    if header == nil {
+        return "", "", nil
+    }
+    if header.FirstChild.Type != html.ElementNode {
+        title = header.FirstChild.Data
+    } else if header.FirstChild.DataAtom == atom.A {
+        title = header.FirstChild.FirstChild.Data
+        for _, d := range header.FirstChild.Attr {
+            if d.Key == "href" {
+                url = d.Val
+            }
+        }
+    } 
+    if url == "" && header.Parent.DataAtom == atom.A {
+        for _, d := range header.FirstChild.Attr {
+            if d.Key == "href" {
+                url = d.Val
+            }
+        }
+    }
+    return title, url, nil
+}
+
+func NewFeedItem(url string, article *html.Node) (*FeedItem, error) {
     var articleBuilder strings.Builder
-    html.Render(&articleBuilder, earticle)
-    f.RawText = articleBuilder.String()
-
-    etime, err := getHtmlElement(earticle, "time")
+    html.Render(&articleBuilder, article)
+    item := FeedItem{
+        Url: url,
+        RawText: articleBuilder.String(),
+    }
+    etime, err := getHtmlElement(article, "time")
     if err != nil {
-        return err
+        return nil, err
     }
     var pubTime time.Time
     for _, d := range etime.Attr {
@@ -137,26 +191,70 @@ func (f *FeedItem) ParseContent(content string) error {
             pubTime, err = parseTime(d.Val)
         }
         if err != nil {
-            return  fmt.Errorf("Error parsing time: %w", err)
+            return nil, fmt.Errorf("Error parsing time: %w", err)
         }
-        f.PubTime = pubTime
+        item.PubTime = pubTime
     }
-    return nil 
+    title, itemurl, _ := getTitleAndUrl(article)
+    if title == "" {
+        title = pubTime.Format("Jan 02 2006")
+    }
+    if itemurl == "" {
+        itemurl = url
+    }
+    if itemurl != "" && !strings.HasPrefix(itemurl, "http://") && !strings.HasPrefix(itemurl, "https://") {
+        itemurl = path.Join(url, itemurl)
+    }
+    item.Title = title
+    item.Url = itemurl
+    return &item, nil 
 }
 
-func NewFeedItem(url string) (*FeedItem, error) {
+func (p *SitePage) Parse() ([]*FeedItem, error) {
+    items := make([]*FeedItem, 0)
+    articles, err := getAllElements(p.Root, "article")
+    if err != nil {
+        return nil, errors.New("No article elements found")
+    }
+    for _, article := range articles {
+        item, parseErr := NewFeedItem(p.Url, article)
+        if parseErr != nil {
+            p.Errors = append(p.Errors, parseErr)
+        } else {
+            items = append(items, item)
+        }
+    }
+    if len(p.Errors) > 0 {
+        errorStrs := make([]string, 0)
+        for _, perr := range p.Errors {
+            errorStrs = append(errorStrs, perr.Error())
+        }
+        p.ErrStr = errors.New(strings.Join(errorStrs, "\n")).Error()
+    }
+    return items, nil
+}
+
+func NewSitePage(url string) (*SitePage, error) {
     rawhtml, err := fetchPage(url)
     if err != nil {
         return nil, fmt.Errorf("Could not fetch page '%s': %w", url, err)
     }
-    item := FeedItem{
-        Url: url,
-    }
-    err = item.ParseContent(rawhtml);
+    nodeRoot, err := html.Parse(strings.NewReader(rawhtml))
     if err != nil {
-        return nil, fmt.Errorf("Could not parse feed item: %w", err)
+        return nil, fmt.Errorf("Error parsing HTML: %w", err)
     }
-    return &item, nil
+    page := SitePage{
+        Url: url,
+        Root: nodeRoot,
+        Errors: make([]error, 0),
+    }
+    nodeTitle, err := getHtmlElement(nodeRoot, "title")
+    if err != nil {
+        page.Title = url
+    } else {
+        page.Title = nodeTitle.FirstChild.Data
+    }
+    return &page, nil
 }
 
 func NewFeedInfo(name, base_url, desc, author string, page_urls...string) (*FeedInfo, error) {
@@ -168,11 +266,16 @@ func NewFeedInfo(name, base_url, desc, author string, page_urls...string) (*Feed
         Errors: make(map[string]string, 10),
     }
     for _,url := range info.PageUrls {
-        item, err := NewFeedItem(url)
+        page, err := NewSitePage(url)
+        if err != nil {
+            info.Errors[url] = err.Error()
+        }
+        pageItems, err := page.Parse()
         if err != nil {
             info.Errors[url] = err.Error()
         } else {
-            info.Items = append(info.Items, item)
+            info.Items = append(info.Items, pageItems...)
+            info.Errors[url] = page.ErrStr
         }
     }
     return &info, nil

feed/feed_test.go

@@ -1,12 +1,15 @@
 package feed_test
 
 import (
+	"strings"
 	"testing"
 	"time"
+
 	"git.32bit.cafe/yequari/webweav.ing/feed"
+	"golang.org/x/net/html"
 )
 
-func TestTimeParsing(t *testing.T) {
+func TestTimeParsingFormat(t *testing.T) {
     testDate, err := time.Parse("2006-Jan-02 15:04:05 -7", "2004-May-14 07:30:55 -7")
     if err != nil {
         t.Errorf("creating test date failed: %s", err)
@@ -19,35 +22,38 @@ func TestTimeParsing(t *testing.T) {
     }{
             {
                 "YYYY-MM-DD",
-                `<html><head></head><body><article><time datetime="2004-05-14">May 14 2004</time>hello world</article></body></html>`,
+                `<article><time datetime="2004-05-14">May 14 2004</time>hello world</article>`,
                 time.DateOnly,
             },
             {
                 "YYYY-MM-DD HH:MM",
-                `<html><head></head><body><article><time datetime="2004-05-14 07:30">May 14 2004</time>hello world</article></body></html>`,
+                `<article><time datetime="2004-05-14 07:30">May 14 2004</time>hello world</article>`,
                 "2006-01-02 15:04",
             },
             {
                 "YYYY-MM-DD HH:MM:SS",
-                `<html><head></head><body><article><time datetime="2004-05-14 07:30:55">May 14 2004</time>hello world</article></body></html>`,
+                `<article><time datetime="2004-05-14 07:30:55">May 14 2004</time>hello world</article>`,
                 "2006-01-02 15:04:05",
             },
             {
                 "YYYY-MM-DDTHH:MM:SS",
-                `<html><head></head><body><article><time datetime="2004-05-14T07:30:55">May 14 2004</time>hello world</article></body></html>`,
+                `<article><time datetime="2004-05-14T07:30:55">May 14 2004</time>hello world</article>`,
                 "2006-01-02T15:04:05",
             },
             {
                 "YYYY-MM-DDTHH:MM",
-                `<html><head></head><body><article><time datetime="2004-05-14T07:30">May 14 2004</time>hello world</article></body></html>`,
+                `<article><time datetime="2004-05-14T07:30">May 14 2004</time>hello world</article>`,
                 "2006-01-02T15:04",
             },
     }
 
     for _, tt := range tests {
         t.Run(tt.name, func (t *testing.T) {
-            item := feed.FeedItem{}
-            err := item.ParseContent(tt.input)
+            html, err := html.Parse(strings.NewReader(tt.input))
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            item, err := feed.NewFeedItem("", html)
             if err != nil {
                 t.Errorf("error: %s", err)
             }
@@ -61,38 +67,231 @@ func TestTimeParsing(t *testing.T) {
     }
 }
 
-
-func TestParseFeedItem(t *testing.T) {
+func TestArticleTimeParsing(t *testing.T) {
     testDate, err := time.Parse("2006-Jan-02", "2004-May-14") 
     if err != nil {
         t.Errorf("creating test date failed: %s", err)
     }
+    testDate2, err := time.Parse("2006-Jan-02", "2004-May-07") 
+    if err != nil {
+        t.Errorf("creating test date failed: %s", err)
+    }
     var tests = []struct {
         name string
         input string
-        want_time *time.Time
-        want_article string
+        want_time []*time.Time
     }{
             {
                 "article and time stripped out of basic HTML",
                 "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article></body></html>", 
-                &testDate, 
-                "<article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article>",
+                []*time.Time{&testDate}, 
+            },
+            {
+                "multiple articles",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article><article><time datetime=\"2004-05-07\">May 7 2004</time>this is a second article</article></body></html>", 
+                []*time.Time{&testDate, &testDate2},
             },
     }
 
     for _, tt := range tests {
         t.Run(tt.name, func (t *testing.T) {
-            item := feed.FeedItem{}
-            err := item.ParseContent(tt.input)
+            html, err := html.Parse(strings.NewReader(tt.input))
             if err != nil {
                 t.Errorf("error: %s", err)
             }
-            if item.RawText != tt.want_article {
-                t.Errorf("got %s, want %s", item.RawText, tt.want_article)
+            page := feed.SitePage{
+                Url: "",
+                Title: "",
+                Root: html, 
+                Errors: make([]error, 0),
+            }
+            items, err := page.Parse()
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            for i, item := range items {
+                if tt.want_time[i] != nil && !item.PubTime.Equal(*tt.want_time[i]) {
+                    t.Errorf("got %s, want %s", item.PubTime, *tt.want_time[i])
+                }
+            }
+        })
+    }
+}
+
+func TestArticleUrls(t *testing.T) {
+    var tests = []struct {
+        name string
+        input string
+        want_url []string
+    }{
+            {
+                "article without url",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article></body></html>", 
+                []string{""},
+            },
+            {
+                "one article with one url",
+                "<html><head></head><body><article><h1><a href=\"https://example.com\">Title</a></h1><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article></body></html>", 
+                []string{"https://example.com"},
+            },
+            {
+                "multiple articles",
+                "<html><head></head><body><article><h1><a href=\"https://example.com/example1\">Title</a></h1><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article><article><h1><a href=\"https://example.com/example2\">Title</a></h1><time datetime=\"2004-05-07\">May 7 2004</time>this is a second article</article></body></html>", 
+                []string{"https://example.com/example1", "https://example.com/example2"},
+            },
+            {
+                "one article with multiple urls",
+                "<html><head></head><body><article><h1><a href=\"https://example.com\">Title</a></h1><time datetime=\"2004-05-14\">May 14 2004</time><a href=\"https://google.com\">click me</a><p>hello world</p></article></body></html>", 
+                []string{"https://example.com"},
+            },
+            {
+                "one article with multiple h1 urls",
+                "<html><head></head><body><article><h1><a href=\"https://example.com\">Title</a></h1><time datetime=\"2004-05-14\">May 14 2004</time><h1><a href=\"https://google.com\">click me</a></h1><p>hello world</p></article></body></html>", 
+                []string{"https://example.com"},
+            },
+    }
+
+    for _, tt := range tests {
+        t.Run(tt.name, func (t *testing.T) {
+            html, err := html.Parse(strings.NewReader(tt.input))
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            page := feed.SitePage{
+                Url: "",
+                Title: "",
+                Root: html, 
+                Errors: make([]error, 0),
+            }
+            items, err := page.Parse()
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            for i, item := range items {
+                if item.Url != tt.want_url[i] {
+                    t.Errorf("got %s, want %s", item.Url, tt.want_url[i])
+                }
+            }
+        })
+    }
+}
+
+func TestArticleTitles(t *testing.T) {
+    var tests = []struct {
+        name string
+        input string
+        want_title []string
+    }{
+            {
+                "article and time stripped out of basic HTML",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article></body></html>", 
+                []string{"May 14 2004"},
+            },
+            {
+                "multiple articles",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article><article><time datetime=\"2004-05-07\">May 7 2004</time>this is a second article</article></body></html>", 
+                []string{"May 14 2004", "May 07 2004"},
+            },
+            {
+                "multiple articles with h1",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h1>Hello</h1>hello world</article><article><time datetime=\"2004-05-07\"><h1>World</h1>May 7 2004</time>this is a second article</article></body></html>", 
+                []string{"Hello", "World"},
+            },
+            {
+                "article with h1",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h1>Hello</h1>hello world</article></body></html>", 
+                []string{"Hello"},
+            },
+            {
+                "article with h2",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h2>Hello</h2>hello world</article></body></html>", 
+                []string{"Hello"},
+            },
+            {
+                "article with h3",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h3>Hello</h3>hello world</article></body></html>", 
+                []string{"Hello"},
+            },
+            {
+                "article with h1 and h2",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h1>Hello</h1><h2>World</h2>hello world</article></body></html>", 
+                []string{"Hello"},
+            },
+            {
+                "article with h2 and h3",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h3>Hello</h3><h2>World</h2>hello world</article></body></html>", 
+                []string{"World"},
+            },
+            {
+                "article with multiple h1",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time><h1>Hello</h1><h1>World</h1>hello world</article></body></html>", 
+                []string{"Hello"},
+            },
+    }
+
+    for _, tt := range tests {
+        t.Run(tt.name, func (t *testing.T) {
+            html, err := html.Parse(strings.NewReader(tt.input))
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            page := feed.SitePage{
+                Url: "",
+                Title: "",
+                Root: html, 
+                Errors: make([]error, 0),
+            }
+            items, err := page.Parse()
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            for i, item := range items {
+                if item.Title != tt.want_title[i] {
+                    t.Errorf("got %s, want %s", item.Title, tt.want_title[i])
+                }
+            }
+        })
+    }
+}
+
+func TestArticleParsing(t *testing.T) {
+    var tests = []struct {
+        name string
+        input string
+        want_article []string
+    }{
+            {
+                "article and time stripped out of basic HTML",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article></body></html>", 
+                []string{"<article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article>"},
+            },
+            {
+                "multiple articles",
+                "<html><head></head><body><article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article><article><time datetime=\"2004-05-07\">May 7 2004</time>this is a second article</article></body></html>", 
+                []string{"<article><time datetime=\"2004-05-14\">May 14 2004</time>hello world</article>", "<article><time datetime=\"2004-05-07\">May 7 2004</time>this is a second article</article>"},
+            },
+    }
+
+    for _, tt := range tests {
+        t.Run(tt.name, func (t *testing.T) {
+            html, err := html.Parse(strings.NewReader(tt.input))
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            page := feed.SitePage{
+                Url: "",
+                Title: "",
+                Root: html, 
+                Errors: make([]error, 0),
+            }
+            items, err := page.Parse()
+            if err != nil {
+                t.Errorf("error: %s", err)
+            }
+            for i, item := range items {
+                if item.RawText != tt.want_article[i] {
+                    t.Errorf("got %s, want %s", item.RawText, tt.want_article[i])
                 }
-            if tt.want_time != nil && !item.PubTime.Equal(*tt.want_time) {
-                t.Errorf("got %s, want %s", item.PubTime, *tt.want_time)
             }
         })
     }