source: fedd/federation/ns2topdl.py @ f24fc8d

#!/usr/local/bin/python

import os,sys
import subprocess
import tempfile
import logging
from deter import topdl

import os.path

from util import *
from deter import fedid
from remote_service import xmlrpc_handler, soap_handler
from service_error import *
from authorizer import authorizer, abac_authorizer


class nullHandler(logging.Handler):
    def emit(self, record): pass

fl = logging.getLogger("fedd.splitter")
fl.addHandler(nullHandler())

class ns2topdl_local:
    def __init__(self, config=None, auth=None):
        """
        Intialize the various attributes, most from the config object
        """
        self.debug = config.getboolean("ns2topdl", "debug")
        self.muxmax = config.getint("ns2topdl", "muxmax", 3)
        self.tclsh = config.get("ns2topdl", "tclsh", 
                "/usr/local/bin/otclsh")
        self.tcl_splitter = config.get("ns2topdl", "tcl_splitter",
                "/usr/testbed/lib/ns2ir/parse.tcl")
        self.auth_type = config.get('ns2topdl', 'auth_type') or 'legacy'
        access_db = config.get("ns2topdl", "accessdb", None)
        self.allow_any = config.getboolean("ns2topdl", "allow_any", False)
        auth_dir = config.get('ns2topdl', 'auth_dir')

        self.log = logging.getLogger("fedd.ns2topdl")
        set_log_level(config, "ns2topdl", self.log)
        self.trace_file = sys.stderr

        set_log_level(config, "ns2topdl", self.log)

        if auth:
            self.auth= auth
        else:
            self.auth = authorizer()
            self.log.warning("[ns2topdl] No authorizer passed in, " +\
                    "using local one")


        if self.auth_type == 'legacy':
            if access_db and self.allow_any: 
                raise service_error(service_error.internal, 
                        "Cannot specify both an access database and " + 
                        "allow_any for ns2topdl")
            
            if access_db:
                try:
                    read_simple_accessdb(access_db, self.auth, 'ns2topdl')
                except EnvironmentError, e:
                    raise service_error(service_error.internal,
                            "Error reading accessDB %s: %s" % (access_db, e))
                except ValueError:
                    raise service_error(service_error.internal, "%s" % e)
            elif self.allow_any:
                auth.set_global_attribute("ns2topdl")
        elif self.auth_type == 'abac':
            self.auth = abac_authorizer(load=auth_dir)
        else:
            raise service_error(service_error.internal, 
                    "Unknown auth_type: %s" % self.auth_type)


        # Dispatch tables
        self.soap_services = {\
                'Ns2Topdl': soap_handler("Ns2Topdl", self.run_ns2topdl),
        }

        self.xmlrpc_services = {\
                'Ns2Topdl': xmlrpc_handler('Ns2Topdl', self.run_ns2topdl),
        }

    def run_ns2topdl(self, req, fid):
        """
        The external interface to tcl to topdl translation.

        Creates a working directory, translates the incoming description using
        the tcl script.
        """

        if self.allow_any:
            self.auth.set_attribute(fid, 'ns2topdl')

        access_ok, proof = self.auth.check_attribute(fid, 'ns2topdl',
            with_proof=True)

        if not access_ok:
            raise service_error(service_error.access, "Access Denied", 
                proof=proof)

        try:
            tmpdir = tempfile.mkdtemp(prefix="ns2topdl-")
        except EnvironmentError:
            raise service_error(service_error.internal, "Cannot create tmp dir")

        tclfile = os.path.join(tmpdir, "experiment.tcl")
        # save error output in case the parse fails.
        errfile = os.path.join(tmpdir, "errfile")
        pid = "dummy"
        gid = "dummy"
        eid = "dummy"
        master = "dummy"

        req = req.get('Ns2TopdlRequestBody', None)
        if not req:
            raise service_error(service_error.req,
                    "Bad request format (no Ns2TopdlRequestBody)")
        # The tcl parser needs to read a file so put the content into that file
        descr=req.get('description', None)
        if descr:
            file_content=descr.get('ns2description', None)
            if file_content:
                try:
                    f = open(tclfile, 'w')
                    f.write(file_content)
                    f.close()
                    ef = open(errfile, 'w')
                except EnvironmentError:
                    raise service_error(service_error.internal,
                            "Cannot write temp experiment description")
            else:
                raise service_error(service_error.req, 
                        "Only ns2descriptions supported")
        else:
            raise service_error(service_error.req, "No description")

        
        tclcmd = [self.tclsh, self.tcl_splitter, '-t', '-x', 
            str(self.muxmax), '-m', master]
        tclcmd.extend([pid, gid, eid, tclfile])
        self.log.debug("Calling splitter %s" % " ".join(tclcmd))
        # This is just fantastic.  As a side effect the parser copies
        # tb_compat.tcl into the current directory, so that directory
        # must be writable by the fedd user.  Doing this in the
        # temporary subdir ensures this is the case.
        tclparser = subprocess.Popen(tclcmd, stdout=subprocess.PIPE, 
                stderr=ef, cwd=tmpdir)

        try:
            top = topdl.topology_from_xml(file=tclparser.stdout, 
                    top="experiment")
        except:
            top = None

        if top is None:
            # There was an ns parsing error, gather up the error from the
            # errfile and raise a service_error containing the error text
            try:
                ef = open(errfile, 'r')
                parse_err = ef.read()
                ef.close()
            except EnvironmentError:
                raise service_error(service_error.internal,
                        "Cannot read error string")

            raise service_error(service_error.req, 
                    "Cannot parse ns file: %s" % parse_err)

        # Walk up tmpdir, deleting as we go
        for path, dirs, files in os.walk(tmpdir, topdown=False):
            for f in files:
                os.remove(os.path.join(path, f))
            for d in dirs:
                os.rmdir(os.path.join(path, d))
        os.rmdir(tmpdir)

        resp = { 
                'experimentdescription':  { 
                    'topdldescription': top.to_dict(),
                    },
                'proof': proof.to_dict(),
                }

        return resp