Merge pull request #114 from valeriupredoi/fix_auto_download_permissions

Fix auto download permissions

bgcval2/download_from_mass.py

@@ -37,6 +37,7 @@
 from socket import gethostname
 import shutil
 import os
+from pwd import getpwuid
 import stat
 from glob import glob
 from re import findall
@@ -407,9 +408,20 @@ def download_from_mass(
 
     paths = get_paths(config_user)
     outputFold = folder([paths.ModelFolder_pref,  jobID,] )
-    # make this folder group writeable. 
     st = os.stat(outputFold)
-    os.chmod(outputFold, st.st_mode | stat.S_IWGRP)
+
+    # Check permissions on the output folder 
+    i_can_write_this = os.access(outputFold, os.W_OK)
+    if i_can_write_this:
+        # I created this folder and I own it.
+        # make this folder group writeable.
+        os.chmod(outputFold, st.st_mode | stat.S_IWGRP)
+    else:
+        # Someone else created it and they own it,
+        # so I can't change permissions.
+        uname = getpwuid(st.st_uid).pw_name
+        print('WARNING: someone else (', uname, ') owns this directory, so you may not be able to download files.')
+        print('WARNING: Ask them politely to run "chmod g+w ',outputFold,'"')
 
     deleteBadLinksAndZeroSize(outputFold, jobID)
 
@@ -483,8 +495,25 @@ def download_from_mass(
     if auto_download:
         shared_file_path = os.path.join(paths.shared_mass_scripts, os.path.basename(download_script_path))
         print('writing file in shared path', shared_file_path)
-        shutil.copy(download_script_path, shared_file_path)
 
+        # check destination permissions:
+        i_can_write_this = os.access(shared_file_path, os.W_OK)
+        if i_can_write_this:
+            # I created this file and I own it:
+            # make local copy group writable:
+            os.chmod(download_script_path, st.st_mode | stat.S_IWGRP)
+
+            # copy local to shared folder: 
+            shutil.copy(download_script_path, shared_file_path)
+
+            # make shared copy group writable: (possibly overkill)
+            os.chmod(shared_file_path, st.st_mode | stat.S_IWGRP)
+        else:
+            # I don't have permission to edit this file. Someone else does:
+            uname = getpwuid(os.stat(shared_file_path).st_uid).pw_name
+            print('WARNING: someone else (', shared_file_path, ') owns this directory, so you may not be able to download files.')
+            print('WARNING: Ask them politely to run "chmod g+w ', shared_file_path,'"')
+
     fixFilePaths(outputFold, jobID, debug=False,)
     deleteBadLinksAndZeroSize(outputFold, jobID, debug=False,)
 
@@ -598,13 +627,14 @@ def deleteBadLinksAndZeroSize(outputFold, jobID, debug=True):
     bashCommand1 = "find " + outputFold + "/. -size 0 -print -delete"
     bashCommand2 = "find -L " + outputFold + "/. -type l -delete  -print"
 
-    if debug: print("deleteBadLinksAndZeroSize:\t", bashCommand1)
+    bashCommand1 = bashCommand1.replace('//', '/')
+    bashCommand2 = bashCommand2.replace('//', '/')
 
+    print("deleteBadLinksAndZeroSize:\t", bashCommand1)
     process1 = subprocess.Popen(bashCommand1.split(), stdout=subprocess.PIPE)
     output1 = process1.communicate()[0]
 
-    if debug: print("deleteBadLinksAndZeroSize:\t", bashCommand2)
-
+    print("deleteBadLinksAndZeroSize:\t", bashCommand2)
     process2 = subprocess.Popen(bashCommand2.split(), stdout=subprocess.PIPE)
     output2 = process2.communicate()[0]
 

tests/unit/test_download_from_mass_permissions.py

@@ -0,0 +1,40 @@
+import os
+import shutil
+import stat
+
+from bgcval2.download_from_mass import download_from_mass as dfm
+
+
+def test_allowed_user():
+    user_home = os.path.expanduser('~')
+    output_folder = "bgcval2/local_test/BGC_data/u-xxx/"
+    run_dir = os.path.join(user_home, output_folder)
+    if not os.path.exists(run_dir):
+        os.makedirs(run_dir)
+    dfm(jobID="u-xxx",
+        doMoo=False,
+        auto_download=False,
+        config_user="defaults"
+    )
+    try:
+        assert os.stat(run_dir).st_mode == 16893
+    # when stat mode is 16877 (equivalent to chmod 877)
+    except AssertionError:
+        assert os.stat(run_dir).st_mode == 16877
+
+
+def test_disallowed_user():
+    user_home = os.path.expanduser('~')
+    output_folder = "bgcval2/local_test/BGC_data/u-yyy/"
+    run_dir = os.path.join(user_home, output_folder)
+    if not os.path.exists(run_dir):
+        os.makedirs(run_dir)
+    st = os.stat(run_dir)
+    os.chmod(run_dir, False)
+    dfm(jobID="u-yyy",
+        doMoo=False,
+        auto_download=False,
+        config_user="defaults"
+    )
+    assert os.stat(run_dir).st_mode == 16384
+    shutil.rmtree(run_dir, ignore_errors=True)