added usage

paperless.sh

@@ -10,6 +10,23 @@ load_env () {
     [ -z "$BASE_URL" ] && { echo "Parameter BASE_URL is not present in env file, please fill it with the URL of your paperless server." >&2; exit 1; }
 }
 
+print_usage () {
+    cat << END_OF_COMMENT
+    $(basename "$0") get_tasks | put_document <file>
+
+      commands:
+        get_tasks       Get the list of tasks. This is not formatted, i.e. you'll
+                        have to pipe it yourself through a formatter.
+        put_document    Uploads the document under <file> to your paperless
+                        instance.
+
+      return values:
+        If everything went alright, $(basename "$0") returns 0. Every other return
+        value indicates an error.
+
+END_OF_COMMENT
+}
+
 AUTH_PARM="Authorization: Token $TOKEN"
 
 case "$1" in
@@ -22,4 +39,8 @@ case "$1" in
         [ ! -r "$2" ] && { echo "file not readable." >&2; exit 1; }
         curl -H "$AUTH_PARM" -X "POST" "${BASE_URL}/api/documents/post_document/" -H 'Accept: application/json' --form "document=@${2}"
     ;;
+    *)
+        print_usage
+        exit 1
+    ;;
 esac