fix attachments download dirpath
diff --git a/migration/README.md b/migration/README.md
index 593a887..0e25a67 100644
--- a/migration/README.md
+++ b/migration/README.md
@@ -38,13 +38,19 @@
 
 ```
 (.venv) migration $ python src/download_jira.py --min 10500 --max 10510
-[2022-07-06 15:43:00,864] INFO:download_jira: Downloading Jira issues in /mnt/hdd/repo/lucene-jira-archive/migration/jira-dump. Attachments are saved in ..
-[2022-07-06 15:43:16,247] INFO:download_jira: Done.
+[2022-07-06 16:22:01,994] INFO:download_jira: Downloading Jira issues in /mnt/hdd/repo/lucene-jira-archive/migration/jira-dump. Attachments are saved in /tmp/attachments.
+[2022-07-06 16:22:17,172] INFO:download_jira: Done.
 
-(.venv) migration $ ls jira-dump/
+(.venv) migration $ ls -1 jira-dump/
 LUCENE-10500.json
 LUCENE-10501.json
 LUCENE-10502.json
+
+(.venv) migration $ ls -1 /tmp/attachments/
+LUCENE-10500
+LUCENE-10501
+LUCENE-10502
+...
 ...
 ```
 
diff --git a/migration/src/common.py b/migration/src/common.py
index 7032489..e4d4727 100644
--- a/migration/src/common.py
+++ b/migration/src/common.py
@@ -9,7 +9,7 @@
 LOG_DIRNAME = "log"
 
 JIRA_DUMP_DIRNAME = "jira-dump"
-JIRA_ATTACHMENTS_DIRPATH = os.getenv("ATTACHMENTS_DL_DIR", str(Path(tempfile.gettempdir()).joinpath("attachments")))
+JIRA_ATTACHMENTS_DIRPATH = os.getenv("ATTACHMENTS_DL_DIR")
 GITHUB_IMPORT_DATA_DIRNAME = "github-import-data"
 GITHUB_REMAPPED_DATA_DIRNAME = "github-remapped-data"
 MAPPINGS_DATA_DIRNAME = "mappings-data"
diff --git a/migration/src/download_jira.py b/migration/src/download_jira.py
index 3db3e80..21c6c20 100644
--- a/migration/src/download_jira.py
+++ b/migration/src/download_jira.py
@@ -10,6 +10,7 @@
 import json
 import time
 from dataclasses import dataclass
+import tempfile
 
 import requests
 
@@ -94,7 +95,7 @@
         dump_dir.mkdir()
     assert dump_dir.exists()
 
-    att_data_dir = Path(JIRA_ATTACHMENTS_DIRPATH)
+    att_data_dir = Path(JIRA_ATTACHMENTS_DIRPATH) if JIRA_ATTACHMENTS_DIRPATH else Path(tempfile.gettempdir()).joinpath("attachments")
     if not att_data_dir.exists():
         att_data_dir.mkdir()
     assert att_data_dir.exists()