switch to config file and implement src path filter

config.yaml

@@ -0,0 +1,40 @@
+server:
+# listen addr:port for default http interface
+  http:
+    addr: "127.0.0.1:8080"
+# listen addr:port for webdav
+  #webdav:
+  #  addr: ""
+# listen addr:port for cache only
+  #cache:
+  #  addr: ""
+# listen addr:port for plain directory listings over http
+  #plain:
+  #  addr: ""
+
+# regex whitelist for allowed filesystem paths
+#path: ""
+
+cache:
+# path to metadata file
+  metadata: "/path/to/metadata.json"
+  src:
+# url path to source files
+    path: "file:///mnt/nfs"
+    #path: "sftp://user@src-host:/home/user"
+# optional hex encoded encryption key (32 bytes)
+    #key: ""
+  dst:
+# url path to cache files
+    path: "file:///mnt/cache"
+    #path: "sftp://user@dst-host:/home/user"
+# optional hex encoded encryption key (32 bytes)
+    #key: ""
+# max parallel preloads
+  #preloads: 1
+# preload buffer size in bytes
+  #buffer: 8192
+# max disk usage quota for the dst cache in GiB
+  #quota: 1
+# block until sftp is connected
+  #blockSFTP: true