systematic use of context managers for dealing with files instead of open()/close...

[nepi.git] / src / nepi / util / sshfuncs.py

diff --git a/src/nepi/util/sshfuncs.py b/src/nepi/util/sshfuncs.py
index 83e2d7e..cfb9908 100644 (file)
--- a/src/nepi/util/sshfuncs.py
+++ b/src/nepi/util/sshfuncs.py
@@ -38,13 +38,11 @@ _re_inet = re.compile("\d+:\s+(?P<name>[a-z0-9_-]+)\s+inet6?\s+(?P<inet>[a-f0-9.
 
 logger = logging.getLogger("sshfuncs")
 
 
 logger = logging.getLogger("sshfuncs")
 

-def log(msg, level, out = None, err = None):
+def log(msg, level = logging.DEBUG, out = None, err = None):

     if out:
         msg += " - OUT: %s " % out
     if out:
         msg += " - OUT: %s " % out

-

     if err:
         msg += " - ERROR: %s " % err
     if err:
         msg += " - ERROR: %s " % err

-

     logger.log(level, msg)
 
 if hasattr(os, "devnull"):
     logger.log(level, msg)
 
 if hasattr(os, "devnull"):


@@ -59,6 +57,7 @@ class STDOUT:
     Special value that when given to rspawn in stderr causes stderr to 
     redirect to whatever stdout was redirected to.
     """
     Special value that when given to rspawn in stderr causes stderr to 
     redirect to whatever stdout was redirected to.
     """

+    pass

 
 class ProcStatus:
     """
 
 class ProcStatus:
     """


@@ -80,8 +79,12 @@ def resolve_hostname(host):
     ip = None
 
     if host in ["localhost", "127.0.0.1", "::1"]:
     ip = None
 
     if host in ["localhost", "127.0.0.1", "::1"]:

-        p = subprocess.Popen("ip -o addr list", shell=True,
-                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        p = subprocess.Popen(
+            "ip -o addr list",
+            shell=True,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+        )

         stdout, stderr = p.communicate()
         m = _re_inet.findall(stdout)
         ip = m[0][1].split("/")[0]
         stdout, stderr = p.communicate()
         m = _re_inet.findall(stdout)
         ip = m[0][1].split("/")[0]


@@ -117,12 +120,15 @@ def openssh_has_persist():
     """
     global OPENSSH_HAS_PERSIST
     if OPENSSH_HAS_PERSIST is None:
     """
     global OPENSSH_HAS_PERSIST
     if OPENSSH_HAS_PERSIST is None:

-        proc = subprocess.Popen(["ssh","-v"],
-            stdout = subprocess.PIPE,
-            stderr = subprocess.STDOUT,
-            stdin = open("/dev/null","r") )
-        out,err = proc.communicate()
-        proc.wait()
+        with open("/dev/null") as null:
+            proc = subprocess.Popen(
+                ["ssh", "-v"],
+                stdout = subprocess.PIPE,
+                stderr = subprocess.STDOUT,
+                stdin = null,
+            )
+            out,err = proc.communicate()
+            proc.wait()

         
         vre = re.compile(r'OpenSSH_(?:[6-9]|5[.][8-9]|5[.][1-9][0-9]|[1-9][0-9]).*', re.I)
         OPENSSH_HAS_PERSIST = bool(vre.match(out))
         
         vre = re.compile(r'OpenSSH_(?:[6-9]|5[.][8-9]|5[.][1-9][0-9]|[1-9][0-9]).*', re.I)
         OPENSSH_HAS_PERSIST = bool(vre.match(out))


@@ -160,9 +166,8 @@ def make_server_key_args(server_key, host, port):
     if os.environ.get('NEPI_STRICT_AUTH_MODE',"").lower() not in ('1','true','on'):
         user_hosts_path = '%s/.ssh/known_hosts' % (os.environ.get('HOME',""),)
         if os.access(user_hosts_path, os.R_OK):
     if os.environ.get('NEPI_STRICT_AUTH_MODE',"").lower() not in ('1','true','on'):
         user_hosts_path = '%s/.ssh/known_hosts' % (os.environ.get('HOME',""),)
         if os.access(user_hosts_path, os.R_OK):

-            f = open(user_hosts_path, "r")
-            tmp_known_hosts.write(f.read())
-            f.close()
+            with open(user_hosts_path, "r") as f:
+                tmp_known_hosts.write(f.read())

         
     tmp_known_hosts.flush()
     
         
     tmp_known_hosts.flush()
     


@@ -189,12 +194,12 @@ def shell_escape(s):
         return s
     else:
         # unsafe string - escape
         return s
     else:
         # unsafe string - escape

-        def escp(c):
+        def escape(c):

             if (32 <= ord(c) < 127 or c in ('\r','\n','\t')) and c not in ("'",'"'):
                 return c
             else:
                 return "'$'\\x%02x''" % (ord(c),)
             if (32 <= ord(c) < 127 or c in ('\r','\n','\t')) and c not in ("'",'"'):
                 return c
             else:
                 return "'$'\\x%02x''" % (ord(c),)

-        s = ''.join(map(escp,s))
+        s = ''.join(map(escape, s))

         return "'%s'" % (s,)
 
 def eintr_retry(func):
         return "'%s'" % (s,)
 
 def eintr_retry(func):


@@ -303,13 +308,13 @@ def rexec(command, host, user,
         stdout = stderr = stdin = None
 
     return _retry_rexec(args, log_msg, 
         stdout = stderr = stdin = None
 
     return _retry_rexec(args, log_msg, 

-            stderr = stderr,
-            stdin = stdin,
-            stdout = stdout,
-            env = env, 
-            retry = retry, 
-            tmp_known_hosts = tmp_known_hosts,
-            blocking = blocking)
+                        stderr = stderr,
+                        stdin = stdin,
+                        stdout = stdout,
+                        env = env, 
+                        retry = retry, 
+                        tmp_known_hosts = tmp_known_hosts,
+                        blocking = blocking)

 
 def rcopy(source, dest,
         port = None,
 
 def rcopy(source, dest,
         port = None,


@@ -344,9 +349,13 @@ def rcopy(source, dest,
     tmp_known_hosts = None
 
     args = ['scp', '-q', '-p', '-C',
     tmp_known_hosts = None
 
     args = ['scp', '-q', '-p', '-C',

+            # 2015-06-01 Thierry: I am commenting off blowfish
+            # as this is not available on a plain ubuntu 15.04 install
+            # this IMHO is too fragile, shoud be something the user
+            # decides explicitly (so he is at least aware of that dependency)

             # Speed up transfer using blowfish cypher specification which is 
             # faster than the default one (3des)
             # Speed up transfer using blowfish cypher specification which is 
             # faster than the default one (3des)

-            '-c', 'blowfish',
+            # '-c', 'blowfish',

             # Don't bother with localhost. Makes test easier
             '-o', 'NoHostAuthenticationForLocalhost=yes',
             '-o', 'ConnectTimeout=60',
             # Don't bother with localhost. Makes test easier
             '-o', 'NoHostAuthenticationForLocalhost=yes',
             '-o', 'ConnectTimeout=60',


@@ -399,22 +408,22 @@ def rcopy(source, dest,
             blocking = True)
 
 def rspawn(command, pidfile, 
             blocking = True)
 
 def rspawn(command, pidfile, 

-        stdout = '/dev/null', 
-        stderr = STDOUT, 
-        stdin = '/dev/null',
-        home = None, 
-        create_home = False, 
-        sudo = False,
-        host = None, 
-        port = None, 
-        user = None, 
-        gwuser = None,
-        gw = None,
-        agent = None, 
-        identity = None, 
-        server_key = None,
-        tty = False,
-        strict_host_checking = True):
+           stdout = '/dev/null', 
+           stderr = STDOUT, 
+           stdin = '/dev/null',
+           home = None, 
+           create_home = False, 
+           sudo = False,
+           host = None, 
+           port = None, 
+           user = None, 
+           gwuser = None,
+           gw = None,
+           agent = None, 
+           identity = None, 
+           server_key = None,
+           tty = False,
+           strict_host_checking = True):

     """
     Spawn a remote command such that it will continue working asynchronously in 
     background. 
     """
     Spawn a remote command such that it will continue working asynchronously in 
     background. 


@@ -500,15 +509,15 @@ def rspawn(command, pidfile,
 
 @eintr_retry
 def rgetpid(pidfile,
 
 @eintr_retry
 def rgetpid(pidfile,

-        host = None, 
-        port = None, 
-        user = None, 
-        gwuser = None,
-        gw = None,
-        agent = None, 
-        identity = None,
-        server_key = None,
-        strict_host_checking = True):
+            host = None, 
+            port = None, 
+            user = None, 
+            gwuser = None,
+            gw = None,
+            agent = None, 
+            identity = None,
+            server_key = None,
+            strict_host_checking = True):

     """
     Returns the pid and ppid of a process from a remote file where the 
     information was stored.
     """
     Returns the pid and ppid of a process from a remote file where the 
     information was stored.


@@ -679,23 +688,27 @@ fi
     return (out, err), proc
 
 def _retry_rexec(args,
     return (out, err), proc
 
 def _retry_rexec(args,

-        log_msg,
-        stdout = subprocess.PIPE,
-        stdin = subprocess.PIPE, 
-        stderr = subprocess.PIPE,
-        env = None,
-        retry = 3,
-        tmp_known_hosts = None,
-        blocking = True):
+                 log_msg,
+                 stdout = subprocess.PIPE,
+                 stdin = subprocess.PIPE, 
+                 stderr = subprocess.PIPE,
+                 env = None,
+                 retry = 3,
+                 tmp_known_hosts = None,
+                 blocking = True):

 
     for x in xrange(retry):
 
     for x in xrange(retry):

+        # display command actually invoked when debug is turned on
+        message = " ".join( [ "'{}'".format(arg) for arg in args ] )
+        log("sshfuncs: invoking {}".format(message), logging.DEBUG)

         # connects to the remote host and starts a remote connection
         # connects to the remote host and starts a remote connection

-        proc = subprocess.Popen(args,
-                env = env,
-                stdout = stdout,
-                stdin = stdin, 
-                stderr = stderr)
-        
+        proc = subprocess.Popen(
+            args,
+            env = env,
+            stdout = stdout,
+            stdin = stdin, 
+            stderr = stderr,
+        )        

         # attach tempfile object to the process, to make sure the file stays
         # alive until the process is finished with it
         proc._known_hosts = tmp_known_hosts
         # attach tempfile object to the process, to make sure the file stays
         # alive until the process is finished with it
         proc._known_hosts = tmp_known_hosts