Lots of features, first version that reliably crawls Geminispace.

- [x] Concurrent downloading with workers
- [x] Concurrent connection limit per host
- [x] URL Blacklist
- [x] Save image/* and text/* files
- [x] Configuration via environment variables
- [x] Storing snapshots in PostgreSQL
- [x] Proper response header & body UTF-8 and format validation
.

.
This commit is contained in:
2024-10-21 20:03:28 +03:00
parent 212345764b
commit fee7d3e01c
37 changed files with 1231 additions and 319 deletions

139
main.go
View File

@@ -1,137 +1,56 @@
package main
import (
"gemini-grc/config"
"gemini-grc/gemini"
"gemini-grc/logging"
"os"
"strings"
"os/signal"
"sync"
"time"
"syscall"
"github.com/jmoiron/sqlx"
"github.com/rs/zerolog"
zlog "github.com/rs/zerolog/log"
)
var CONFIG Config
var wg sync.WaitGroup
func main() {
wg.Add(1)
CONFIG = *getConfig()
config.CONFIG = *config.GetConfig()
zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
zerolog.SetGlobalLevel(CONFIG.logLevel)
zerolog.SetGlobalLevel(config.CONFIG.LogLevel)
zlog.Logger = zlog.Output(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: "[2006-01-02 15:04:05]"})
if err := runApp(); err != nil {
LogError("Application error: %w", err)
logging.LogError("Application error: %w", err)
os.Exit(1)
}
}
func runApp() error {
// urls := []string{"gemini://smol.gr"}
// urls := []string{"gemini://gemini.circumlunar.space/users/solderpunk/gemlog/orphans-of-netscape.gmi"} // Test 31 redirect
// urls := []string{"gemini://zaibatsu.circumlunar.space/~solderpunk/gemlog/orphans-of-netscape.gmi"}
// urls := []string{"gemini://farcaster.net/berlin/dared.jpg"}
// urls := []string{"gemini://smol.gr/media/amstrad_cpc_6128.jpg", "https://go.dev/blog/go-brand/Go-Logo/PNG/Go-Logo_Blue.png"}
urls := []string{"gemini://tlgs.one/", "gemini://gmi.noulin.net/", "gemini://warmedal.se/~antenna/"}
logging.LogInfo("Starting up. Press Ctrl+C to exit")
sigs := make(chan os.Signal, 1)
signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
queue := make(chan string, 1000)
results := make(chan Snapshot, 100)
done := make(chan struct{})
db := gemini.ConnectToDB()
go spawnStatsReport(queue, results)
go resultsHandler(queue, results)
spawnWorkers(CONFIG.numOfWorkers, queue, results)
// !!! DANGER !!!
// Removes all rows and adds some seed URLs.
// populateDB(db)
for _, url := range urls {
queue <- url
}
<-done
defer func(db *sqlx.DB) {
err := db.Close()
if err != nil {
// TODO properly log & hangle error
panic(err)
}
}(db)
go gemini.SpawnWorkers(config.CONFIG.NumOfWorkers, db)
<-sigs
logging.LogInfo("Received SIGINT or SIGTERM signal, exiting")
return nil
}
func spawnStatsReport(queue chan string, results chan Snapshot) {
ticker := time.NewTicker(time.Duration(time.Second * 10))
defer ticker.Stop()
for range ticker.C {
LogInfo("Queue length: %d", len(queue))
LogInfo("Results length: %d", len(results))
}
}
func spawnWorkers(numOfWorkers int, queue <-chan string, results chan Snapshot) {
LogInfo("Spawning %d workers", numOfWorkers)
for i := 0; i < numOfWorkers; i++ {
go func(i int) {
worker(i, queue, results)
}(i)
}
}
func resultsHandler(queue chan string, results <-chan Snapshot) {
for result := range results {
if result.Error != nil {
LogError("[%s] %w", result.URL, result.Error)
} else {
LogDebug("[%s] Done", result.URL)
for _, link := range result.Links {
if strings.HasPrefix(link.Full, "gemini://") {
go func(link GeminiUrl) {
queue <- link.Full
// fmt.Printf("Sent %s to queue\n", link.Full)
}(link)
}
}
// if result.MimeType == "text/gemini" {
// result.Data = ""
// fmt.Printf(SnapshotToJSON(result))
// }
}
}
}
func worker(id int, queue <-chan string, results chan Snapshot) {
for url := range queue {
if !shouldVisit(url) {
LogInfo("Skipping %s", url)
continue
}
LogInfo("Worker %d visiting %s", id, url)
result, err := Visit(url)
if err != nil {
LogError("[%s] %w", url, err)
continue
}
// If we encountered an error when
// visiting, skip processing
if result.Error != nil {
results <- *result
continue
}
LogDebug("Worker %d processing %s", id, url)
if result.MimeType == "text/gemini" {
result = ProcessGemini(result)
}
if shouldPersist(result) {
LogDebug("Worker %d saving %s", id, url)
SaveSnapshot(CONFIG.rootPath, result)
}
results <- *result
// time.Sleep(time.Duration(rand.IntN(5)) * time.Second)
}
}
func shouldVisit(url string) bool {
if !strings.HasPrefix(url, "gemini://") {
return false
}
return true
}
func shouldPersist(result *Snapshot) bool {
if result.MimeType == "text/gemini" ||
strings.HasPrefix(result.MimeType, "image/") ||
strings.HasPrefix(result.MimeType, "text/") {
return true
}
return false
}