Fix: attempt db rename during reset (#1801)

.gitignore

@@ -10,3 +10,4 @@ benefits/static/sha.txt
 __pycache__/
 .coverage
 .DS_Store
+.venv

bin/init.sh

@@ -1,15 +1,18 @@
 #!/usr/bin/env bash
 set -eux
 
-# remove existing (old) database file
-
-if [[ ${DJANGO_DB_RESET:-true} = true ]]; then
-    # construct the path to the database file from environment or default
-    DB_DIR="${DJANGO_DB_DIR:-.}"
-    DB_FILE="${DB_DIR}/django.db"
+# make the path to the database file from environment or default
+DB_DIR="${DJANGO_DB_DIR:-.}"
+DB_FILE="${DB_DIR}/django.db"
+DB_RESET="${DJANGO_DB_RESET:-true}"
 
-    # -f forces the delete (and avoids an error when the file doesn't exist)
-    rm -f "${DB_FILE}"
+# remove existing (old) database file
+if [[ $DB_RESET = true && -f $DB_FILE ]]; then
+    # rename then delete the new file
+    # trying to avoid a file lock on the existing file
+    # after marking it for deletion
+    mv "${DB_FILE}" "${DB_FILE}.old"
+    rm "${DB_FILE}.old"
 fi
 
 # run database migrations