memorable download codes

src/store.rs

@@ -1,6 +1,7 @@
 use std::{collections::HashMap, io::ErrorKind, path::PathBuf, str::FromStr};
 
 use log::{debug, error, info, warn};
+use rand::{distributions::{Alphanumeric, DistString}, thread_rng, Rng};
 use serde::{Deserialize, Serialize};
 use time::OffsetDateTime;
 use tokio::{
@@ -15,6 +16,17 @@ const GIGA: u64 = 1024*1024*1024;
 const DEFAULT_MAX_UPLOAD_SIZE: u64 = 16*GIGA;
 const DEFAULT_MAX_STORAGE_SIZE: u64 = 64*GIGA;
 
+pub fn gen_storage_code() -> String {
+    if std::env::var("TRANSBEAM_MNEMONIC_CODES").as_deref() == Ok("false") {
+        Alphanumeric.sample_string(&mut thread_rng(), 8)
+    } else {
+        mnemonic::to_string(thread_rng().gen::<[u8; 4]>())
+    }
+}
+
+pub fn is_valid_storage_code(s: &str) -> bool {
+    s.as_bytes().iter().all(|c| c.is_ascii_alphanumeric() || c == &b'-')
+}
 
 pub(crate) fn storage_dir() -> PathBuf {
     PathBuf::from(std::env::var("TRANSBEAM_STORAGE_DIR").unwrap_or_else(|_| String::from(DEFAULT_STORAGE_DIR)))
@@ -133,7 +145,7 @@ impl FileStore {
                     // Handle this case separately, because we don't
                     // want to try to delete it if it's not the sort
                     // of path we're expecting
-                    if !crate::util::is_ascii_alphanumeric(&key) {
+                    if !is_valid_storage_code(&key) {
                         error!("Invalid key in persistent storage: {}", key);
                         continue;
                     }