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lfc2_python

lfc2_python

Section: Python Reference (3) Updated: $Date: 2010-04-23 09:16:40 +0200 (Fri, 23 Apr 2010) $
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NAME

lfc2 - New python interface to the LFC client API
lfc2thr - Thread enabled version of Python interface to the LFC  

SYNOPSIS

import lfc2 as lfc


import lfc2thr as lfc
lfc.init()

 

DESCRIPTION

The lfc module permits you to access the LFC client interface from python programs. The lfc module is a swig wrapping of the standard C interface. For detailed descriptions of each function see the individual man page of each function.

The lfcthr module is a version of the lfc module supporting multi-threaded Python clients. Its usage is similar to the usage of the lfc module except the obligatory initialisation call lfcthr.init() in the main program before threads are started.
   

FUNCTIONS

lfc_aborttrans ( )

lfc_access ( string path, int amode ) -> bool access

lfc_accessr ( string sfn, int amode ) -> bool access

lfc_addreplica ( string guid, struct lfc_fileid *file_uniqueid, string server, string sfn, char status, char f_type, string poolname, string fs )

lfc_addreplicax ( string guid, struct lfc_fileid *file_uniqueid, string server, string sfn, char status, char f_type, string poolname, string fs, char r_type, string setname )

lfc_chdir ( string path )

lfc_chmod ( string path, mode_t mode )

lfc_chown ( string path, uid_t new_uid, gid_t new_gid )

lfc_client_setAuthorizationId ( uid_t uid, gid_t gid, string mech, string id )

lfc_client_setVOMS_data ( string voname, stringlist vomsdata )

lfc_closedir ( lfc_DIR dirp )

lfc_creatg ( string path, string guid, mode_t mode )

lfc_delcomment ( string path )

lfc_delete ( string path )

lfc_delfilesbyguid ( ListOfString guids, int force ) -> ListOfInt result

lfc_delfilesbyname ( ListOfString names, intforce ) -> ListOfInt results

lfc_delfilesbypattern ( string path, string pattern, int force ) -> ListOf struct lfc_filestatus results

lfc_delreplica ( string guid, struct lfc_fileid *file_uniqueid, string sfn )

lfc_delreplicas ( ListOfString sfns, string se ) -> ListOfInt results

lfc_delreplicasbysfn ( ListOfString sfns, ListOfString guids ) -> ListOfInt results

lfc_endsess ( )

lfc_endtrans ( )

lfc_getacl ( string path, ) -> ListOf struct lfc_acl acls

lfc_getcomment ( string path ) -> string comment

lfc_getcwd ( ) -> string dir

lfc_getifcevers ( ) -> string version

lfc_getlinks ( string path, string guid ) -> ListOf struct lfc_linkinfo links

lfc_getreplica ( string path, string guid, string se ) -> ListOf struct lfc_filereplica replicas

lfc_getreplicas ( ListOfString guids, string se ) -> ListOf struct lfc_filereplicas replicas

lfc_getreplicasl ( ListOfString paths, string se ) -> ListOf struct lfc_filereplicas replicas

lfc_getreplicass ( ListOfString paths, ) -> ListOf struct lfc_filereplicas replicas

lfc_getreplicax ( string path, string guid, string se ) -> ListOf struct lfc_filereplicax replicas

lfc_lchown ( string path, uid_t new_uid, gid_t new_gid )

lfc_listlinks ( string path, string guid, int flags, lfc_list *listp ) -> struct lfc_linkinfo link

lfc_listreplica ( string path, string guid, int flags, lfc_list *listp ) -> struct lfc_filereplica replica

lfc_listreplicax ( string poolname, string server, string fs, int flags, lfc_list * listp ) -> struct lfc_filereplica replica

lfc_listrepset ( string setname, int flags, lfc_list *listp ) -> struct lfc_filereplicax replica

lfc_lstat ( string path ) -> struct lfc_filestat statbuf

lfc_mkdir ( string path, mode_t mode )

lfc_mkdirg ( string path, string guid, mode_t mode )

lfc_modreplica ( string sfn, string setname, string poolname, string server )

lfc_modreplicax ( string sfn, string setname, string poolname, string server, string fs, char r_type )

lfc_opendir ( string path ) -> lfc_DIR dir

lfc_opendirg ( string path, string guid ) -> lfc_DIR dir

lfc_opendirxg ( string server, string path, string guid ) -> lfc_DIR dir

lfc_ping ( string server ) -> string info

lfc_readdir ( lfc_DIR dirp ) -> struct dirent dirent

lfc_readdirc ( lfc_DIR dirp ) -> struct lfc_direncomm dirent

lfc_readdirg ( lfc_DIR dirp ) -> struct lfc_direnstatg dirent

lfc_readdirx ( lfc_DIR dirp ) -> struct lfc_direnstat dirent

lfc_readdirxc ( lfc_DIR dirp ) -> struct lfc_direnstatc dirent

lfc_readdirxp ( lfc_DIR dirp, string pattern, string se = None ) -> struct lfc_direnrep dirent

lfc_readdirxr ( lfc_DIR dirp, string se = None ) -> struct lfc_direnrep dirent

lfc_readlink ( string path ) -> string link

lfc_registerfiles ( ListOf struct lfc_filereg files ) -> ListOfInt results

lfc_rename ( string oldpath, string newpath )

lfc_rewinddir ( lfc_DIR dirp )

lfc_rmdir ( string path )

lfc_setacl ( string path, ListOf struct lfc_acl acls )

lfc_setatime ( string path, struct lfc_fileid file_uniqueid )

lfc_setcomment ( string path, string comment )

lfc_setfsize ( string path, struct lfc_fileid file_uniqueid, long filesize )

lfc_setfsizec ( string path, struct lfc_fileid file_uniqueid, long filesize, string csumtype, string csumvalue )

lfc_setfsizeg ( string guid, long filesize, string csumtype, string csumvalue )

lfc_setptime ( string sfn, long ptime )

lfc_setratime ( string sfn )

lfc_setrltime ( string sfn, long ltime )

lfc_setrstatus ( string sfn, char status )

lfc_setrtype ( string sfn, char type )

lfc_startsess ( string server, string comment )

lfc_starttrans ( string server, string comment )

lfc_stat ( string path ) -> struct lfc_filestat statbuf

lfc_statg ( string path, string guid ) -> struct lfc_filestatg statbuf

lfc_statr ( string sfn) ) -> struct lfc_filestatg statbuf

lfc_symlink ( string target, string linkname )

lfc_umask ( mode_t cmask ) -> mode_t oldmask

lfc_undelete ( string path )

lfc_unlink ( string path )

lfc_utime ( string path, struct utimbuf times )

lfc_entergrpmap ( gid_t gid, string groupname )

lfc_enterusrmap ( uid_t uid, string username )

lfc_getgrpbygid ( gid_t gid ) -> string group

lfc_getgrpbygids ( ListOfgid_t gids ) -> ListOfString groups

lfc_getgrpbynam ( string groupname ) -> gid_t gid

lfc_getgrpmap ( ) -> ListOf struct lfc_groupinfo infos

lfc_getidmap ( string username, ListOfString vo_roles ) -> uid_t uid, ListOf gid_t gids

lfc_getusrbynam ( string username ) -> uid_t uid

lfc_getusrbyuid ( uid_t uid ) -> string user

lfc_getusrmap ( ) -> ListOf struct lfc_userinfo userinfo

lfc_modifygrpmap ( gid_t gid, string newname )

lfc_modifyusrmap ( uid_t uid, string newname )

lfc_rmgrpmap ( gid_t gid, string groupname )

lfc_rmusrmap ( uid_t uid, string username )

 

STRUCTURES

Sometimes you need to specify a structure as an input argument (eg. struct lfc_acl, struct lfc_list, etc.). For that purpose, the module includes structure constructors, named exactly as the structure.

Thus, to create struct lfc_acl or struct lfc_list, you have to do the following:

    lfcacl = lfc.lfc_acl()
    lfclist = lfc.lfc_list()

If you want to see how to use it in a real case, please have a look at examples.

 

ERRORS

As you can see, no error code is returned. When an error occurs, an exception is raised with a description of the error.

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# stat an existing entry in the LFC and print the GUID
"""

name = "/grid/dteam/my.test"

try:
   stat = lfc.lfc_statg(name,"")
except Exception:
   traceback.print_exc()
   sys.exit(1)

guid = stat.guid
print "The GUID for " + name + " is " + guid

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# list the replicas of a given entry, starting from the GUID
"""

guid = "6a3164e0-a4d7-4abe-9f76-e3b8882735d1"

listp = lfc.lfc_list()
flag = lfc.CNS_LIST_BEGIN

print "Listing replicas for GUID " + guid

num_replicas=0

try:
   while(1):
      res = lfc.lfc_listreplica("",guid,flag,listp)
      flag = lfc.CNS_LIST_CONTINUE

      if res == None:
         break
      else:
         rep_name = res.sfn
         print "Replica: " + rep_name
         num_replicas = num_replicas + 1

   lfc.lfc_listreplica("",guid,lfc.CNS_LIST_END,listp)
   print "Found " + str(num_replicas) + " replica(s)"
except Exception:
   traceback.print_exc()
   sys.exit(1)

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# setting and retrieving a comment on a file
"""

file = "/grid/dteam/my.test"
comment = "MyComment"

try:
   lfc.lfc_setcomment(file,comment)

   comment = lfc.lfc_getcomment(file)
   print "Read back comment " + comment
except Exception:
   traceback.print_exc()
   sys.exit(1)

 

EXAMPLE

#!/usr/bin/python

"""
# Using the lfc_readdirxr method
"""

import sys
import traceback
import lfc2 as lfc

name = "/grid/dteam/my.test"

try:
   dir = lfc.lfc_opendir(name)

   while 1:
      entry = lfc.lfc_readdirxr(dir)
      if entry == None:
         break
      print entry.d_name
      for i in range(entry.nbreplicas):
         print " ==> %s" % entry.rep[i].sfn

   lfc.lfc_closedir(dir)
except TypeError, x:
   print " ==> None"
except Exception:
   traceback.print_exc()
   sys.exit(1)

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getreplica method
"""

file = "/grid/dteam/my.test"

try:
   list = lfc.lfc_getreplica(file, "", "")
except Exception:
   traceback.print_exc()
   sys.exit(1)

for i in list:
   print i.host
   print i.sfn

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getacl and lfc_setacl methods to add a user ACL
"""

file = "/grid/dteam/my.test"

try:
   acls_list = lfc.lfc_getacl(file)
except Exception:
   traceback.print_exc()
   sys.exit(1)

for i in acls_list:
        print i.a_type
        print i.a_id
        print i.a_perm

# When adding a first ACL for a given user, you also need to add the mask
# When adding the second user ACL, it is not necessary anymore

acl_user = lfc.lfc_acl()
acl_mask = lfc.lfc_acl()

acl_user.a_type = lfc.CNS_ACL_USER
acl_user.a_id = 18701           # user id
acl_user.a_perm = lfc.S_IROTH | lfc.S_IXOTH

acl_mask.a_type = lfc.CNS_ACL_MASK
acl_mask.a_id = 0                       # no user id specified
acl_mask.a_perm = lfc.S_IROTH | lfc.S_IXOTH

acls_list.append(acl_user)
acls_list.append(acl_mask)

try:
   lfc.lfc_setacl(file, acls_list)
except Exception:
   traceback.print_exc()
   sys.exit(1)

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getacl and lfc_setacl methods to remove a user ACL
"""

file = "/grid/dteam/my.test"

try:
   acls_list = lfc.lfc_getacl(file)
except Exception:
   traceback.print_exc()
   sys.exit(1)

for i in acls_list:
        print i.a_type
        print i.a_id
        print i.a_perm

del acls_list[1]        # delete a given user ACL from the list of ACLs

try:
   lfc.lfc_setacl(file, acls_list)
except Exception:
   traceback.print_exc()
   sys.exit(1)

 

EXAMPLE

#!/usr/bin/env python
import lfc2thr as lfc
import os
from threading import Thread

class slave(Thread):

   def __init__ (self):
      Thread.__init__(self)
      
   def run(self):
        ....
        result = lfc.lfc_getreplica("", guid, "")
        ....
        return
        
if __name__ == '__main__':

    os.environ['LFC_HOST'] = 'my_lfc.cern.ch'

    #   Threaded library initialisation
    lfc.init()

    ....
    #   Start up of threads
    for i in xrange(totalNumberOfSlaves):
        slv = slave(i)
        slv.start()
        
    ....

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getusrmap method
"""

try:
   list = lfc.lfc_getusrmap()
except Exception:
   traceback.print_exc()
   sys.exit(1)

for i in list:
   print i.userid + " " + i.username

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getgrpmap method
"""

try:
   list = lfc.lfc_getgrpmap()
except Exception:
   traceback.print_exc()
   sys.exit(1)
    
for i in list:
   print i.gid + " " + i.groupname

 

EXAMPLE

#!/usr/bin/python

import sys
import traceback
import lfc2 as lfc

"""
# Using the lfc_getidmap method
"""

userdn = "user certificate DN"
vo_roles = ["dteam"]

try:
   uid, gids = lfc.lfc_getidmap (userdn, vo_roles)
except Exception:
   traceback.print_exc()
   sys.exit(1)

print "uid=", uid
print "gids=", gids

 

SEE ALSO

LFC C interface man pages


 

Index

NAME
SYNOPSIS
DESCRIPTION
FUNCTIONS
STRUCTURES
ERRORS
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
EXAMPLE
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 21:49:14 GMT, April 16, 2011