feat: implemented many commands

- added register command
- added reset command
- added users command
- added agg command
- added feeds command

internal/rss/rss.go

@@ -0,0 +1,61 @@
+package rss
+
+import (
+	"context"
+	"encoding/xml"
+	"html"
+	"net/http"
+)
+
+type RSSItem struct {
+	Title       string `xml:"title"`
+	Link        string `xml:"link"`
+	Description string `xml:"description"`
+	PubDate     string `xml:"pubDate"`
+}
+
+type RSSChannel struct {
+	Title       string    `xml:"title"`
+	Link        string    `xml:"link"`
+	Description string    `xml:"description"`
+	Item        []RSSItem `xml:"item"`
+}
+
+type RSSFeed struct {
+	Channel RSSChannel `xml:"channel"`
+}
+
+func FetchFeed(ctx context.Context, feedURL string) (*RSSFeed, error) {
+	var rssFeed RSSFeed
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, feedURL, nil)
+	req.Header.Set("User-Agent", "gator")
+
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := http.DefaultClient.Do(req)
+
+	if err != nil {
+		return nil, err
+	}
+
+	defer res.Body.Close()
+
+	err = xml.NewDecoder(res.Body).Decode(&rssFeed)
+
+	if err != nil {
+		return nil, err
+	}
+
+	rssFeed.Channel.Title = html.UnescapeString(rssFeed.Channel.Title)
+	rssFeed.Channel.Description = html.UnescapeString(rssFeed.Channel.Description)
+
+	for _, item := range rssFeed.Channel.Item {
+		item.Title = html.UnescapeString(item.Title)
+		item.Description = html.UnescapeString(item.Description)
+	}
+
+	return &rssFeed, nil
+}