Move subp into its own module. (#416)

This was painful, but it finishes a TODO from cloudinit/subp.py.

It moves the following from util to subp:
  ProcessExecutionError
  subp
  which
  target_path

I moved subp_blob_in_tempfile into cc_chef, which is its only caller.
That saved us from having to deal with it using write_file
and temp_utils from subp (which does not import any cloudinit things now).

It is arguable that 'target_path' could be moved to a 'path_utils' or
something, but in order to use it from subp and also from utils,
we had to get it out of utils.

1 files changed, 11 insertions, 10 deletions

diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py
index 01d9adf2..89312b9e 100755
--- a/cloudinit/sources/DataSourceAzure.py
+++ b/cloudinit/sources/DataSourceAzure.py
@@ -22,6 +22,7 @@ from cloudinit.event import EventType
 from cloudinit.net.dhcp import EphemeralDHCPv4
 from cloudinit import sources
 from cloudinit.sources.helpers import netlink
+from cloudinit import subp
 from cloudinit.url_helper import UrlError, readurl, retry_on_url_exc
 from cloudinit import util
 from cloudinit.reporting import events
@@ -139,8 +140,8 @@ def find_dev_from_busdev(camcontrol_out, busdev):
 
 def execute_or_debug(cmd, fail_ret=None):
     try:
-        return util.subp(cmd)[0]
-    except util.ProcessExecutionError:
+        return subp.subp(cmd)[0]
+    except subp.ProcessExecutionError:
         LOG.debug("Failed to execute: %s", ' '.join(cmd))
         return fail_ret
 
@@ -252,11 +253,11 @@ DEF_PASSWD_REDACTION = 'REDACTED'
 def get_hostname(hostname_command='hostname'):
     if not isinstance(hostname_command, (list, tuple)):
         hostname_command = (hostname_command,)
-    return util.subp(hostname_command, capture=True)[0].strip()
+    return subp.subp(hostname_command, capture=True)[0].strip()
 
 
 def set_hostname(hostname, hostname_command='hostname'):
-    util.subp([hostname_command, hostname])
+    subp.subp([hostname_command, hostname])
 
 
 @azure_ds_telemetry_reporter
@@ -343,7 +344,7 @@ class DataSourceAzure(sources.DataSource):
 
         try:
             invoke_agent(agent_cmd)
-        except util.ProcessExecutionError:
+        except subp.ProcessExecutionError:
             # claim the datasource even if the command failed
             util.logexc(LOG, "agent command '%s' failed.",
                         self.ds_cfg['agent_command'])
@@ -982,7 +983,7 @@ def perform_hostname_bounce(hostname, cfg, prev_hostname):
     if command == "builtin":
         if util.is_FreeBSD():
             command = BOUNCE_COMMAND_FREEBSD
-        elif util.which('ifup'):
+        elif subp.which('ifup'):
             command = BOUNCE_COMMAND_IFUP
         else:
             LOG.debug(
@@ -993,7 +994,7 @@ def perform_hostname_bounce(hostname, cfg, prev_hostname):
     shell = not isinstance(command, (list, tuple))
     # capture=False, see comments in bug 1202758 and bug 1206164.
     util.log_time(logfunc=LOG.debug, msg="publishing hostname",
-                  get_uptime=True, func=util.subp,
+                  get_uptime=True, func=subp.subp,
                   kwargs={'args': command, 'shell': shell, 'capture': False,
                           'env': env})
     return True
@@ -1003,7 +1004,7 @@ def perform_hostname_bounce(hostname, cfg, prev_hostname):
 def crtfile_to_pubkey(fname, data=None):
     pipeline = ('openssl x509 -noout -pubkey < "$0" |'
                 'ssh-keygen -i -m PKCS8 -f /dev/stdin')
-    (out, _err) = util.subp(['sh', '-c', pipeline, fname],
+    (out, _err) = subp.subp(['sh', '-c', pipeline, fname],
                             capture=True, data=data)
     return out.rstrip()
 
@@ -1015,7 +1016,7 @@ def pubkeys_from_crt_files(flist):
     for fname in flist:
         try:
             pubkeys.append(crtfile_to_pubkey(fname))
-        except util.ProcessExecutionError:
+        except subp.ProcessExecutionError:
             errors.append(fname)
 
     if errors:
@@ -1057,7 +1058,7 @@ def invoke_agent(cmd):
     # this is a function itself to simplify patching it for test
     if cmd:
         LOG.debug("invoking agent: %s", cmd)
-        util.subp(cmd, shell=(not isinstance(cmd, list)))
+        subp.subp(cmd, shell=(not isinstance(cmd, list)))
     else:
         LOG.debug("not invoking agent")