initial

hnblogs.go

@@ -0,0 +1,102 @@
+package hnblogs
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/rand"
+	"net/http"
+	"sync"
+)
+
+const BlogsURL = "https://raw.githubusercontent.com/surprisetalk/blogs.hn/main/blogs.json"
+
+// Blog represents a single blog entry.
+type Blog struct {
+	URL   string `json:"url"`
+	Title string `json:"title"`
+	About string `json:"about"`
+	Now   string `json:"now"`
+	Feed  string `json:"feed"`
+	Desc  string `json:"desc"`
+}
+
+var (
+	blogs       []Blog
+	fetchError  error
+	once        sync.Once
+)
+
+// FetchBlogs fetches the list of blogs and memoizes it in RAM.
+func FetchBlogs() ([]Blog, error) {
+	once.Do(func() {
+		resp, err := http.Get(BlogsURL)
+		if err != nil {
+			fetchError = fmt.Errorf("failed to fetch blogs: %v", err)
+			return
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			fetchError = fmt.Errorf("failed to fetch blogs: status code %d", resp.StatusCode)
+			return
+		}
+
+		var fetchedBlogs []Blog
+		if err := json.NewDecoder(resp.Body).Decode(&fetchedBlogs); err != nil {
+			fetchError = fmt.Errorf("failed to decode blogs JSON: %v", err)
+			return
+		}
+
+		blogs = fetchedBlogs
+	})
+
+	return blogs, fetchError
+}
+
+// GetBlogs returns the memoized list of blogs.
+func GetBlogs() ([]Blog, error) {
+	return FetchBlogs()
+}
+
+// RandomBlog returns a random blog from the list of blogs.
+func RandomBlog() (Blog, error) {
+	blogs, err := GetBlogs()
+	if err != nil {
+		return Blog{}, err
+	}
+
+	return blogs[rand.Intn(len(blogs))], nil
+}
+
+// RandomBlogs returns n random blogs from the list of blogs.
+func RandomBlogs(n int) ([]Blog, error) {
+	blogs, err := GetBlogs()
+	if err != nil {
+		return nil, err
+	}
+
+	if n <= 0 || n > len(blogs) {
+		return nil, fmt.Errorf("invalid number of blogs requested")
+	}
+
+	selected := make([]Blog, n)
+	for i := range selected {
+		selected[i] = blogs[rand.Intn(len(blogs))]
+	}
+
+	return selected, nil
+}
+
+// NthBlog returns the nth blog from the list of blogs.
+func NthBlog(n int) (Blog, error) {
+	blogs, err := GetBlogs()
+	if err != nil {
+		return Blog{}, err
+	}
+
+	if n < 0 || n >= len(blogs) {
+		return Blog{}, fmt.Errorf("index out of range")
+	}
+
+	return blogs[n], nil
+}