Fix crontab on systems with crontab

intake/crontab.py

@@ -1,5 +1,6 @@
 from pathlib import Path
 import os
+import shutil
 import subprocess
 import sys
 
@@ -28,15 +29,13 @@ def update_crontab_entries(data_path: Path):
     Update the intake-managed section of the user's crontab.
     """
     # If there is no crontab command available, quit early.
-    cmd = ("command", "-v", "crontab")
-    print("Executing", *cmd, file=sys.stderr)
-    crontab_exists = subprocess.run(cmd, shell=True, stdout=subprocess.PIPE)
-    if not crontab_exists.stdout:
-        print("Could not update crontab", file=sys.stderr)
+    crontab = shutil.which("crontab")
+    if not crontab:
+        print("No crontab found, skipping", file=sys.stderr)
         return
 
     # Get the current crontab
-    cmd = ["crontab", "-e"]
+    cmd = [crontab, "-e"]
     print("Executing", *cmd, file=sys.stderr)
     get_crontab = subprocess.run(
         cmd,
@@ -77,7 +76,7 @@ def update_crontab_entries(data_path: Path):
     print("Updating", len(new_crontab_lines) - 2, "crontab entries", file=sys.stderr)
 
     # Save the updated crontab
-    cmd = ["crontab", "-"]
+    cmd = [crontab, "-"]
     print("Executing", *cmd, file=sys.stderr)
     new_crontab: bytes = "\n".join(new_crontab_lines).encode("utf8")
     save_crontab = subprocess.Popen(