move bundle files only on success (#12)

Author: tomkralidis

pywis_topics/bundle.py

@@ -22,7 +22,9 @@
 import io
 import logging
 import os
+from pathlib import Path
 import shutil
+import tempfile
 import zipfile
 
 import click
@@ -34,7 +36,11 @@
 
 USERDIR = get_userdir()
 
+TEMPDIR = tempfile.TemporaryDirectory()
+TEMPDIR2 = Path(tempfile.TemporaryDirectory().name)
+
 WIS2_TOPIC_HIERARCHY_DIR = get_userdir() / 'wis2-topic-hierarchy'
+WIS2_TOPIC_HIERARCHY_DIR_TEMP = TEMPDIR2 / 'wis2-topic-hierarchy'
 
 
 @click.group()
@@ -56,7 +62,7 @@ def sync_bundle() -> None:
         shutil.rmtree(USERDIR)
 
     LOGGER.debug('Downloading WIS2 topic hierarchy')
-    WIS2_TOPIC_HIERARCHY_DIR.mkdir(parents=True, exist_ok=True)
+    WIS2_TOPIC_HIERARCHY_DIR_TEMP.mkdir(parents=True, exist_ok=True)
 
     ZIPFILE_URL = 'https://wmo-im.github.io/wis2-topic-hierarchy/wth-bundle.zip'  # noqa
     FH = io.BytesIO(urlopen_(ZIPFILE_URL).read())
@@ -66,17 +72,27 @@ def sync_bundle() -> None:
             LOGGER.debug(f'Processing entry "{name}"')
             filename = os.path.basename(name)
 
-            dest_file = WIS2_TOPIC_HIERARCHY_DIR / filename
+            dest_file = WIS2_TOPIC_HIERARCHY_DIR_TEMP / filename
             LOGGER.debug(f'Creating "{dest_file}"')
             with z.open(name) as src, dest_file.open('wb') as dest:
                 shutil.copyfileobj(src, dest)
 
     LOGGER.debug('Downloading IANA TLDs')
     IANA_URL = 'https://data.iana.org/TLD/tlds-alpha-by-domain.txt'
-    iana_file = WIS2_TOPIC_HIERARCHY_DIR / 'tlds-alpha-by-domain.txt'
+    iana_file = WIS2_TOPIC_HIERARCHY_DIR_TEMP / 'tlds-alpha-by-domain.txt'
     with iana_file.open('wb') as fh:
         fh.write(urlopen_(f'{IANA_URL}').read())
 
+    LOGGER.debug(f'Removing {USERDIR}')
+    if USERDIR.exists():
+        shutil.rmtree(USERDIR)
+
+    LOGGER.debug(f'Moving files from {TEMPDIR2} to {USERDIR}')
+    shutil.move(TEMPDIR2, USERDIR)
+
+    LOGGER.debug(f'Cleaning up {TEMPDIR}')
+    TEMPDIR.cleanup()
+
 
 @click.command()
 @get_cli_common_options