refactor: modularize code, optimize performance, and improve output f…

…ormatting

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.17 AS builder
+FROM golang:1.20 AS builder
 
 WORKDIR /app
 

README.md

@@ -1,27 +1,41 @@
 # hacker_news
+
 A command line tool that shows the top stories from [Hacker News](https://news.ycombinator.com/) using the [Hacker News API from Firebase](https://github.com/HackerNews/API).
 
 This is a port of an dotnet version, [hn-top](https://github.com/amscotti/hn-top) which I used to learn about Go and understand how to keep the order of the stories when using Goroutines with help of Mutex and WaitGroup.
 
-![hacker_news Output](https://github.com/amscotti/hacker_news/blob/main/hacker_news.png?raw=true)
+![hacker_news Output](hacker_news.png)
 
 ## Building and Running
 
 ### With Go
-* Build with `go build`
-* Then run with `./hacker_news`
+To build and run the application, follow these steps:
+
+1. Clone the repository.
+2. Navigate to the root directory of the project.
+3. Build the binary with `go build`.
+4. Run the binary with `./hacker_news`.
 
 ### With Docker
-* Build with `docker build -t hacker_news . `
-* Then run with `docker run hacker_news`
+To build and run the application with Docker, follow these steps:
+
+1. Clone the repository.
+2. Navigate to the root directory of the project.
+3. Build the Docker image with `docker build -t hacker_news .`.
+4. Run the Docker container with `docker run hacker_news`.
 
-### With pre-build Docker image from [ghcr.io](https://github.com/amscotti/hacker_news/pkgs/container/hacker_news)
-* To download and run, use `docker run ghcr.io/amscotti/hacker_news:main`
+### With pre-built Docker image from [ghcr.io](https://github.com/amscotti/hacker_news/pkgs/container/hacker_news)
+To download and run the pre-built Docker image, follow these steps:
+
+1. Install Docker.
+2. Run the command `docker run ghcr.io/amscotti/hacker_news:main`.
 
 ### Command Line Arguments
+The following command line arguments are available:
+
 ```
 Usage of ./hacker_news:
   -n int
-        Number of top news to show. (default 5)
-  -u    Show source urls.
+        Specify the number of top stories to display (default: 5). (default 5)
+  -u    Include the source URLs of the stories in the output.
 ```

go.mod

@@ -1,3 +1,17 @@
 module github.com/amscotti/hacker_news
 
-go 1.17
+go 1.20
+
+require github.com/charmbracelet/lipgloss v0.7.1
+
+require (
+	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mattn/go-isatty v0.0.17 // indirect
+	github.com/mattn/go-runewidth v0.0.14 // indirect
+	github.com/muesli/reflow v0.3.0 // indirect
+	github.com/muesli/termenv v0.15.1 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
+	github.com/valyala/fastjson v1.6.4
+	golang.org/x/sys v0.6.0 // indirect
+)

go.sum

@@ -0,0 +1,23 @@
+github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
+github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
+github.com/charmbracelet/lipgloss v0.7.1 h1:17WMwi7N1b1rVWOjMT+rCh7sQkvDU75B2hbZpc5Kc1E=
+github.com/charmbracelet/lipgloss v0.7.1/go.mod h1:yG0k3giv8Qj8edTCbbg6AlQ5e8KNWpFujkNawKNhE2c=
+github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
+github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
+github.com/mattn/go-isatty v0.0.17 h1:BTarxUcIeDqL27Mc+vyvdWYSL28zpIhv3RoTdsLMPng=
+github.com/mattn/go-isatty v0.0.17/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
+github.com/mattn/go-runewidth v0.0.14 h1:+xnbZSEeDbOIg5/mE6JF0w6n9duR1l3/WmbinWVwUuU=
+github.com/mattn/go-runewidth v0.0.14/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
+github.com/muesli/reflow v0.3.0 h1:IFsN6K9NfGtjeggFP+68I4chLZV2yIKsXJFNZ+eWh6s=
+github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
+github.com/muesli/termenv v0.15.1 h1:UzuTb/+hhlBugQz28rpzey4ZuKcZ03MeKsoG7IJZIxs=
+github.com/muesli/termenv v0.15.1/go.mod h1:HeAQPTzpfs016yGtA4g00CsdYnVLJvxsS4ANqrZs2sQ=
+github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
+github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/valyala/fastjson v1.6.4 h1:uAUNq9Z6ymTgGhcm0UynUAB6tlbakBrz6CQFax3BXVQ=
+github.com/valyala/fastjson v1.6.4/go.mod h1:CLCAqky6SMuOcxStkYQvblddUtoRxhYMGLrsQns1aXY=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

hackernews/api.go

@@ -0,0 +1,118 @@
+package hackernews
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"sync"
+	"time"
+
+	"github.com/valyala/fastjson"
+)
+
+const (
+	STORIES_URL   = "https://hacker-news.firebaseio.com/v0/topstories.json"
+	ITEM_URL_BASE = "https://hacker-news.firebaseio.com/v0/item"
+)
+
+func createClient() *http.Client {
+	transport := &http.Transport{
+		MaxIdleConns:    100,
+		IdleConnTimeout: 30 * time.Second,
+	}
+	return &http.Client{
+		Transport: transport,
+		Timeout:   time.Duration(10 * time.Second),
+	}
+}
+
+func fetchJSON(url string) (*fastjson.Value, error) {
+	client := createClient()
+	resp, err := client.Get(url)
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch %s: %w", url, err)
+	}
+	defer resp.Body.Close()
+
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response body: %w", err)
+	}
+
+	value, err := fastjson.ParseBytes(data)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse JSON: %w", err)
+	}
+
+	return value, nil
+}
+
+func downloadStory(id int, wg *sync.WaitGroup, m *sync.Mutex, stories map[int]Story) {
+	defer wg.Done()
+
+	url := fmt.Sprintf("%s/%d.json", ITEM_URL_BASE, id)
+
+	value, err := fetchJSON(url)
+	if err != nil {
+		log.Printf("Error fetching story with id %d: %v", id, err)
+		return
+	}
+
+	story := Story{
+		Title:       string(value.GetStringBytes("title")),
+		By:          string(value.GetStringBytes("by")),
+		Descendants: int(value.GetInt("descendants")),
+		Id:          int(value.GetInt("id")),
+		Score:       int(value.GetInt("score")),
+		Time:        int(value.GetInt("time")),
+		Type:        string(value.GetStringBytes("type")),
+		URL:         string(value.GetStringBytes("url")),
+	}
+
+	kids := value.GetArray("kids")
+	for i := range kids {
+		story.Kids = append(story.Kids, int(kids[i].GetInt()))
+	}
+
+	m.Lock()
+	stories[id] = story
+	m.Unlock()
+}
+
+func FetchTopStories(number int, showSourceUrls bool) {
+	value, err := fetchJSON(STORIES_URL)
+	if err != nil {
+		log.Printf("Error fetching top stories: %v", err)
+		return
+	}
+
+	var ids []int
+	valueArray := value.GetArray()
+	for i := 0; i < len(valueArray); i++ {
+		id := int(valueArray[i].GetInt())
+		ids = append(ids, id)
+	}
+
+	if len(ids) > number {
+		ids = ids[:number]
+	}
+
+	storyDetails := make(map[int]Story)
+
+	var m sync.Mutex
+	var wg sync.WaitGroup
+
+	wg.Add(len(ids))
+
+	for _, id := range ids {
+		go downloadStory(id, &wg, &m, storyDetails)
+	}
+
+	wg.Wait()
+
+	for _, id := range ids {
+		story := storyDetails[id]
+		fmt.Print(story.PrintStyling(showSourceUrls))
+	}
+}

hackernews/models.go

@@ -0,0 +1,43 @@
+package hackernews
+
+import (
+	"fmt"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+const (
+	HackerNewsURLFormat = "https://news.ycombinator.com/item?id=%d"
+)
+
+type Story struct {
+	Title       string
+	By          string
+	Descendants int
+	Id          int
+	Kids        []int
+	Score       int
+	Time        int
+	Type        string
+	URL         string
+}
+
+func newStyleWithFGColor(color string) lipgloss.Style {
+	return lipgloss.NewStyle().Foreground(lipgloss.Color(color))
+}
+
+func (s *Story) PrintStyling(showSourceUrl bool) string {
+	titleStyle := newStyleWithFGColor("#FAB005").Bold(true)
+	metaStyle := newStyleWithFGColor("#B8B8B8")
+	linkStyle := newStyleWithFGColor("#69C9D0").Underline(true)
+
+	output := titleStyle.Render(s.Title) + "\n"
+	output += metaStyle.Render(fmt.Sprintf("score: %d\tcomments: %d\tuser: %s", s.Score, s.Descendants, s.By)) + "\n"
+	output += "url: " + linkStyle.Render(fmt.Sprintf(HackerNewsURLFormat, s.Id)) + "\n"
+	if showSourceUrl {
+		output += newStyleWithFGColor("#D6749C").Render(s.URL) + "\n"
+	}
+	output += "\n"
+
+	return output
+}

main.go

@@ -1,117 +1,26 @@
 package main
 
 import (
-	"encoding/json"
+	"errors"
 	"flag"
 	"fmt"
-	"io/ioutil"
-	"log"
-	"net/http"
-	"sync"
-)
 
-const (
-	STORIES_URL   = "https://hacker-news.firebaseio.com/v0/topstories.json"
-	ITEM_URL_BASE = "https://hacker-news.firebaseio.com/v0/item"
+	"github.com/amscotti/hacker_news/hackernews"
 )
 
-type Story struct {
-	Title       string
-	By          string
-	Descendants int
-	Id          int
-	Kids        []int
-	Score       int
-	Time        int
-	Type        string
-	URL         string
-}
-
-func (s *Story) Print(showSourceUrl bool) {
-	fmt.Println(s.Title)
-	fmt.Printf("score: %d\tcomments: %d\tuser: %s\n", s.Score, s.Descendants, s.By)
-	fmt.Printf("url: https://news.ycombinator.com/item?id=%d\n", s.Id)
-	if showSourceUrl {
-		fmt.Println(s.URL)
-	}
-	fmt.Println("")
-}
-
-func downloadStory(id int, wg *sync.WaitGroup, m *sync.Mutex, stories map[int]Story) {
-	url := fmt.Sprintf("%s/%d.json", ITEM_URL_BASE, id)
-
-	rsp, err := http.Get(url)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer rsp.Body.Close()
-
-	data, err := ioutil.ReadAll(rsp.Body)
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	var story Story
-	if err := json.Unmarshal(data, &story); err != nil {
-		log.Fatal(err)
-	}
-
-	m.Lock()
-	stories[id] = story
-	m.Unlock()
-
-	wg.Done()
-}
-
-func fetch(number int, showSourceUrls bool) {
-	fmt.Println("Fetching latest stories...")
-
-	rsp, err := http.Get(STORIES_URL)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer rsp.Body.Close()
-
-	data, err := ioutil.ReadAll(rsp.Body)
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	var ids []int
-	if err := json.Unmarshal(data, &ids); err != nil {
-		log.Fatal(err)
-	}
-
-	if len(ids) > number {
-		ids = ids[:number]
-	}
-
-	storyDetails := make(map[int]Story)
-
-	var m sync.Mutex
-	var wg sync.WaitGroup
-
-	wg.Add(len(ids))
-
-	for _, id := range ids {
-		go downloadStory(id, &wg, &m, storyDetails)
-	}
-
-	wg.Wait()
-
-	for _, id := range ids {
-		story := storyDetails[id]
-		story.Print(showSourceUrls)
-	}
-}
-
 func main() {
 	var number int
 	var showSourceUrls bool
 
-	flag.IntVar(&number, "n", 5, "Number of top news to show.")
-	flag.BoolVar(&showSourceUrls, "u", false, "Show source urls.")
+	flag.IntVar(&number, "n", 5, "Specify the number of top stories to display (default: 5).")
+	flag.BoolVar(&showSourceUrls, "u", false, "Include the source URLs of the stories in the output.")
 	flag.Parse()
 
-	fetch(number, showSourceUrls)
+	if number <= 0 {
+		err := errors.New("number of stories must be a positive integer")
+		fmt.Println(err)
+		return
+	}
+
+	hackernews.FetchTopStories(number, showSourceUrls)
 }