Structured for download project and processing project. Responsibility split

.gitignore

@@ -0,0 +1,2 @@
+data/
+scratch.txt

.idea/m3u8-downloader.iml

@@ -2,7 +2,9 @@
 <module type="WEB_MODULE" version="4">
   <component name="Go" enabled="true" />
   <component name="NewModuleRootManager">
-    <content url="file://$MODULE_DIR$" />
+    <content url="file://$MODULE_DIR$">
+      <excludeFolder url="file://$MODULE_DIR$/data" />
+    </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
   </component>

CLAUDE.md

@@ -0,0 +1,51 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is a Go-based M3U8 downloader that parses HLS (HTTP Live Streaming) playlists to extract video and audio stream metadata. The end goal of this project is to have a listening REST API take in m3u8 urls, parse them, and eventually send to a conversion service.
+
+## Architecture
+
+The project follows a clean separation of concerns:
+
+- **main.go**: Entry point that demonstrates usage of the media package
+- **media/**: Core package containing M3U8 parsing logic
+  - **types.go**: Contains the main parsing logic and data structures (`StreamSet`, `VideoURL`, `AudioURL`)
+  - **utils.go**: Utility functions for parsing attributes and resolution calculations
+
+The `GetStreamMetadata()` function is the main entry point that:
+1. Fetches the M3U8 master playlist via HTTP
+2. Parses the content line by line
+3. Extracts video streams (`#EXT-X-STREAM-INF`) and audio streams (`#EXT-X-MEDIA`)
+4. Returns a `StreamSet` containing all parsed metadata
+
+## Common Development Commands
+
+```bash
+# Build the project
+go build -o m3u8-downloader
+
+# Run the project
+go run main.go
+
+# Run with module support
+go mod tidy
+
+# Test the project (when tests are added)
+go test ./...
+
+# Format code
+go fmt ./...
+```
+
+## Key Data Structures
+
+- `StreamSet`: Root structure containing playlist URL and all streams
+- `VideoURL`: Represents video stream with bandwidth, codecs, resolution, frame rate
+- `AudioURL`: Represents audio stream with media type, group ID, name, and selection flags
+
+## Error Handling
+
+The current implementation uses `panic()` for error handling. When extending functionality, consider implementing proper error handling with returned error values following Go conventions.

cmd/downloader/main.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"fmt"
+	downloader2 "m3u8-downloader/pkg/downloader"
+)
+
+func main() {
+
+	masterUrl := "https://d17cyqyz9yhmep.cloudfront.net/streams/234945/playlist_1752291107574_1752292056713.m3u8"
+
+	stream, err := downloader2.ParseMasterPlaylist(masterUrl)
+	if err != nil {
+		panic(err)
+	}
+
+	audio, video, err := stream.FetchSegmentPlaylists()
+	if err != nil {
+		panic(err)
+	}
+
+	videoPlaylist := downloader2.ParseMediaPlaylist(video)
+	audioPlaylist := downloader2.ParseMediaPlaylist(audio)
+
+	for _, segment := range videoPlaylist.Segments {
+		fmt.Println(segment.URL)
+	}
+
+	for _, segment := range audioPlaylist.Segments {
+		err := downloader2.DownloadTSFile(stream.BuildSegmentURL(segment.URL), downloader2.OutputDirPath)
+		if err != nil {
+			return
+		}
+	}
+}

cmd/proc/main.go

@@ -0,0 +1 @@
+package proc

main.go

@@ -1,27 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"m3u8-downloader/media"
-)
-
-func main() {
-
-	masterUrl := "https://d17cyqyz9yhmep.cloudfront.net/streams/234945/playlist_1752291107574_1752292056713.m3u8"
-
-	stream, err := media.ParseMasterPlaylist(masterUrl)
-	if err != nil {
-		panic(err)
-	}
-
-	audio, video, err := stream.FetchSegmentPlaylists()
-	if err != nil {
-		panic(err)
-	}
-
-	videoPlaylist := media.ParseMediaPlaylist(video)
-	audioPlaylist := media.ParseMediaPlaylist(audio)
-
-	fmt.Println(videoPlaylist)
-	fmt.Println(audioPlaylist)
-}

pkg/downloader/client.go

@@ -1,4 +1,4 @@
-package media
+package downloader
 
 import (
 	"context"
@@ -6,6 +6,9 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"os"
+	"path"
+	"path/filepath"
 	"time"
 )
 
@@ -86,6 +89,31 @@ func FetchPlaylistContent(url string) (string, error) {
 	return string(data), nil
 }
 
+func DownloadTSFile(url string, outputDir string) error {
+	if err := os.MkdirAll(outputDir, 0755); err != nil {
+		return fmt.Errorf("failed to create directory: %w", err)
+	}
+
+	fileName := path.Base(url)
+	filePath := filepath.Join(outputDir, fileName)
+	data, err := defaultClient.Get(url)
+	if err != nil {
+		return err
+	}
+
+	out, err := os.Create(filePath)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+
+	_, err = out.Write(data)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func FetchPlaylistContentWithContext(ctx context.Context, url string) (string, error) {
 	data, err := defaultClient.GetWithContext(ctx, url)
 	if err != nil {

pkg/downloader/constants.go

@@ -1,4 +1,4 @@
-package media
+package downloader
 
 import "time"
 
@@ -14,4 +14,5 @@ const (
 	ClientDefaultTimeout = 30 * time.Second
 	HTTPUserAgent        = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0"
 	PlaylistTypeVOD      = "VOD"
+	OutputDirPath        = "./data"
 )

pkg/downloader/parser.go

@@ -1,4 +1,4 @@
-package media
+package downloader
 
 import (
 	"strconv"

pkg/downloader/playlist.go

@@ -1,4 +1,4 @@
-package media
+package downloader
 
 import (
 	"fmt"

pkg/downloader/segment.go

@@ -1,7 +1,8 @@
-package media
+package downloader
 
 import (
 	"errors"
+	"fmt"
 	"strconv"
 	"strings"
 )
@@ -44,6 +45,10 @@ func (s *StreamSet) FetchSegmentPlaylists() (videoPlaylist, audioPlaylist string
 	return videoContent, audioContent, nil
 }
 
+func (s *StreamSet) BuildSegmentURL(filename string) string {
+	return fmt.Sprintf("%s%s", HTTPSPrefix, s.Metadata.Domain+"/streams/"+s.Metadata.StreamID+"/a/5000/"+filename)
+}
+
 func ParseMediaPlaylist(content string) *MediaPlaylist {
 	lines := strings.Split(content, "\n")
 	var segments []Segment

pkg/downloader/stream.go

@@ -1,4 +1,4 @@
-package media
+package downloader
 
 import (
 	"errors"
@@ -54,7 +54,7 @@ type AudioStream struct {
 
 func NewAudioStream(mediaInfo string) (*AudioStream, error) {
 	if !strings.HasPrefix(mediaInfo, ExtXMedia) {
-		return nil, errors.New("invalid media info line")
+		return nil, errors.New("invalid downloader info line")
 	}
 
 	attributes := parseMediaAttributes(mediaInfo)