feat: add locally syncing and watchdog

internal/utility/environment.go

@@ -1,8 +1,10 @@
 package utility
 
 import (
+	"log/slog"
 	"os"
 	"path/filepath"
+	"slices"
 	"strconv"
 )
 
@@ -13,14 +15,24 @@ type Environment struct {
 	ContentDirectory string
 	Hostname         string
 	Port             int
-	WatchInterval    int
+	WatchdogInterval int
+	WatchdogSyncMode string
 }
 
+var (
+	validSyncModes = []string{
+		"sync",
+		"strict",
+		"dry",
+	}
+)
+
 // part of environment checking
 func safeStringGrab(key, fallback string) string {
 	if v, ok := os.LookupEnv(key); ok {
 		return v
 	}
+	slog.Debug("using fallback", "key", key, "fallback", fallback)
 	return fallback
 }
 
@@ -30,6 +42,17 @@ func safeIntGrab(key string, fallback int) int {
 			return i
 		}
 	}
+	slog.Debug("using fallback", "key", key, "fallback", fallback)
+	return fallback
+}
+
+func safeSyncModeGrab(key, fallback string) string {
+	if v, ok := os.LookupEnv(key); ok {
+		if slices.Contains(validSyncModes, v) {
+			return v
+		}
+	}
+	slog.Debug("using fallback", "key", key, "fallback", fallback)
 	return fallback
 }
 
@@ -48,8 +71,11 @@ func GrabEnvironment() Environment {
 		DataDirectory:    safeStringGrab("DATA_DIR", fbBase),
 		ContentDirectory: safeStringGrab("CONTENT_DIR", fbContent),
 		Hostname:         safeStringGrab("HOSTNAME", "0.0.0.0"),
-
-		Port:          safeIntGrab("PORT", 8080),
-		WatchInterval: safeIntGrab("WATCHDOG_INTERVAL", 60),
+		Port:             safeIntGrab("PORT", 8080),
+		WatchdogInterval: safeIntGrab("WATCHDOG_INTERVAL", 60),
+		// sync: sync local files to the database, for example when you want to allow local inserting files which then get added to the database
+		// strict: make the database leading, this is when you only allow API uploads to be registered, and remove orphaned filesystem files
+		// dry: do nothing
+		WatchdogSyncMode: safeStringGrab("WATCHDOG_SYNC_MODE", "strict"),
 	}
 }

internal/utility/hash.go

@@ -0,0 +1,41 @@
+package utility
+
+import (
+	"crypto/sha512"
+	"encoding/hex"
+	"io"
+	"mime/multipart"
+	"os"
+)
+
+func HashReader(r io.Reader) (string, error) {
+	h := sha512.New()
+	if _, err := io.Copy(h, r); err != nil {
+		return "", err
+	}
+
+	// return the sha checksum in hex
+	return hex.EncodeToString(h.Sum(nil)), nil
+	// alternatively return in base64
+	//return base64.StdEncoding.EncodeToString(h.Sum(nil)), nil
+}
+
+func HashUpload(fileHeader *multipart.FileHeader) (string, error) {
+	stream, err := fileHeader.Open()
+	if err != nil {
+		return "", err
+	}
+	defer stream.Close()
+
+	return HashReader(stream)
+}
+
+func HashFile(path string) (string, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	return HashReader(file)
+}