source: server/lib/gutenbach/server/requests.py @ cad7502

from gutenbach.server.printer import GutenbachPrinter
import gutenbach.ipp as ipp
import gutenbach.ipp.constants as const
from gutenbach.ipp.constants import job_attribute_value_tags, printer_attribute_value_tags
import logging

# initialize logger
logger = logging.getLogger(__name__)

def handler_for(operation):
    """A decorator method to mark a function with the operation id
    that it handles.  This value will be stored in
    'func.ipp_operation'.

    """
    
    def f(func):
        func.ipp_operation = operation
        return func
    return f

class GutenbachRequestHandler(object):

    def __init__(self):
        self.printers = {
            "test": GutenbachPrinter(name="test")
            }
        self.default = "test"
    
    def handle(self, request, response):
        # look up the handler
        handler = None
        handler_name = None
        for d in dir(self):
            if getattr(getattr(self, d), "ipp_operation", None) == request.operation_id:
                handler_name = d
                break
        # we couldn't find a handler, so default to unknown operation
        if handler_name is None:
            handler_name = "unknown_operation"
        # call the handler
        handler = getattr(self, handler_name)
        logger.info("Handling request of type '%s'" % handler_name)
        handler(request, response)

    def unknown_operation(self, request, response):
        logger.warning("Received unknown operation 0x%x" % request.operation_id)
        response.operation_id = const.StatusCodes.OPERATION_NOT_SUPPORTED

    ##### Helper functions

    def _get_printer_attributes(self, printer, request, response):
        attrs = printer.get_printer_attributes(request)
        ipp_attrs = []
        for attr, vals in attrs:
            ipp_vals = [ipp.Value(
                tag=printer_attribute_value_tags[attr],
                value=val) for val in vals]
            ipp_attrs.append(ipp.Attribute(name=attr, values=ipp_vals))
        response.attribute_groups.append(ipp.AttributeGroup(
            const.AttributeTags.PRINTER, ipp_attrs))

    def _get_job_attributes(self, job, request, response):
        attrs = job.get_job_attributes(request)
        ipp_attrs = []
        for attr, vals in attrs:
            ipp_vals = [ipp.Value(
                tag=job_attribute_value_tags[attr],
                value=val) for val in vals]
            ipp_attrs.append(ipp.Attribute(name=attr, values=ipp_vals))
        response.attribute_groups.append(ipp.AttributeGroup(
            const.AttributeTags.JOB, ipp_attrs))

    def _get_job_id(self, request):
        pass
        
    ##### Printer Commands

    def print_job(self, request, response):
        pass

    def validate_job(self, request, response):
        pass

    @handler_for(const.Operations.GET_JOBS)
    def get_jobs(self, request, response):
        """RFC 2911: 3.2.6 Get-Jobs Operation
        
        This REQUIRED operation allows a client to retrieve the list
        of Job objects belonging to the target Printer object. The
        client may also supply a list of Job attribute names and/or
        attribute group names. A group of Job object attributes will
        be returned for each Job object that is returned.

        This operation is similar to the Get-Job-Attributes operation,
        except that this Get-Jobs operation returns attributes from
        possibly more than one object.

        """
        
        reqdict = ipp.ops.verify_get_jobs_request(request)
        printer_name = reqdict['printer-uri']
        if printer_name not in self.printers:
            raise ipp.errors.Attributes(
                "Invalid printer uri: %s" % printer_name,
                [request.attribute_groups[0].attributes[2]])

        # Each job will append a new job attribute group.
        # XXX: we need to honor the things that the request actually asks for
        for job in self.printers[printer_name].get_jobs():
            self._get_job_attributes(job, request, response)

    def print_uri(self, request, response):
        pass

    def create_job(self, request, response):
        pass

    def pause_printer(self, request, response):
        pass

    def resume_printer(self, request, response):
        pass

    @handler_for(const.Operations.GET_PRINTER_ATTRIBUTES)
    def get_printer_attributes(self, request, response):
        """RFC 2911: 3.2.5 Get-Printer-Attributes Operation

        This REQUIRED operation allows a client to request the values
        of the attributes of a Printer object.
        
        In the request, the client supplies the set of Printer
        attribute names and/or attribute group names in which the
        requester is interested. In the response, the Printer object
        returns a corresponding attribute set with the appropriate
        attribute values filled in.

        For Printer objects, the possible names of attribute groups are:
        
        - 'job-template': the subset of the Job Template attributes
          that apply to a Printer object (the last two columns of the
          table in Section 4.2) that the implementation supports for
          Printer objects.

        - 'printer-description': the subset of the attributes
          specified in Section 4.4 that the implementation supports
          for Printer objects.

        - 'all': the special group 'all' that includes all attributes
          that the implementation supports for Printer objects.
        
        Since a client MAY request specific attributes or named
        groups, there is a potential that there is some overlap. For
        example, if a client requests, 'printer-name' and 'all', the
        client is actually requesting the 'printer-name' attribute
        twice: once by naming it explicitly, and once by inclusion in
        the 'all' group. In such cases, the Printer object NEED NOT
        return each attribute only once in the response even if it is
        requested multiple times. The client SHOULD NOT request the
        same attribute in multiple ways.

        It is NOT REQUIRED that a Printer object support all
        attributes belonging to a group (since some attributes are
        OPTIONAL). However, it is REQUIRED that each Printer object
        support all group names.

        """

        # this is just like cups_get_default, except the printer name
        # is given
        reqdict = ipp.ops.verify_get_printer_attributes_request(request)
        printer_name = reqdict['printer-uri']
        if printer_name not in self.printers:
            raise ipp.errors.Attributes(
                "Invalid printer uri: %s" % printer_name,
                [request.attribute_groups[0].attributes[2]])
        
        self._get_printer_attributes(self.printers[printer_name], request, response)

    def set_printer_attributes(self, request, response):
        pass

    ##### Job Commands

    def cancel_job(self, request, response):
        pass

    def send_document(self, request, response):
        pass

    def send_uri(self, request, response):
        pass

    def get_job_attributes(self, request, response):
        reqdict = ipp.ops.verify_get_jobs_request(request)
        printer_name = reqdict['printer-uri']
        job_id = reqdict['job-id']
        
        if printer_name not in self.printers:
            raise ipp.errors.Attributes(
                "Invalid printer uri: %s" % printer_name,
                [request.attribute_groups[0].attributes[2]])
        try:
            job = self.printers[printer_name].get_job(job_id)
        except InvalidJobException:
            raise ipp.errors.Attributes(
                "Invalid job id: %d" % job_id,
                [request.attribute_groups[0].attributes[2]]) # XXX: this is wrong

        # Each job will append a new job attribute group.
        # XXX: we need to honor the things that the request actually asks for
        self._get_job_attributes(job, request, response)

    def set_job_attributes(self, request, response):
        pass

    def cups_get_document(self, request, response):
        pass

    def restart_job(self, request, response):
        pass

    def promote_job(self, request, response):
        pass

    ##### CUPS Specific Commands

    @handler_for(const.Operations.CUPS_GET_DEFAULT)
    def cups_get_default(self, request, response):
        """The CUPS-Get-Default operation (0x4001) returns the default
        printer URI and attributes.

        CUPS-Get-Default Request
        ------------------------

        The following groups of attributes are supplied as part of the
        CUPS-Get-Default request:

        Group 1: Operation Attributes
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.1 of the IPP Model and Semantics
                document.
            'requested-attributes' (1setOf keyword):
                The client OPTIONALLY supplies a set of attribute
                names and/or attribute group names in whose values the
                requester is interested. If the client omits this
                attribute, the server responds as if this attribute
                had been supplied with a value of 'all'.
        
        CUPS-Get-Default Response
        -------------------------

        The following groups of attributes are send as part of the
        CUPS-Get-Default Response:

        Group 1: Operation Attributes
            Status Message:
                The standard response status message.
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.2 of the IPP Model and Semantics
                document.

        Group 2: Printer Object Attributes
            The set of requested attributes and their current values.

        (Source: http://www.cups.org/documentation.php/spec-ipp.html#CUPS_GET_DEFAULT )

        """
            
        self._get_printer_attributes(self.printers[self.default], request, response)

    @handler_for(const.Operations.CUPS_GET_PRINTERS)
    def cups_get_printers(self, request, response):
        """
        The CUPS-Get-Printers operation (0x4002) returns the printer
        attributes for every printer known to the system. This may
        include printers that are not served directly by the server.

        CUPS-Get-Printers Request
        -------------------------
        
        The following groups of attributes are supplied as part of the
        CUPS-Get-Printers request:

        Group 1: Operation Attributes
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.1 of the IPP Model and Semantics
                document.
            'first-printer-name' (name(127)):CUPS 1.2/Mac OS X 10.5
                The client OPTIONALLY supplies this attribute to
                select the first printer that is returned.
            'limit' (integer (1:MAX)):
                The client OPTIONALLY supplies this attribute limiting
                the number of printers that are returned.
            'printer-location' (text(127)): CUPS 1.1.7
                The client OPTIONALLY supplies this attribute to
                select which printers are returned.
            'printer-type' (type2 enum): CUPS 1.1.7
                The client OPTIONALLY supplies a printer type
                enumeration to select which printers are returned.
            'printer-type-mask' (type2 enum): CUPS 1.1.7
                The client OPTIONALLY supplies a printer type mask
                enumeration to select which bits are used in the
                'printer-type' attribute.
            'requested-attributes' (1setOf keyword) :
                The client OPTIONALLY supplies a set of attribute
                names and/or attribute group names in whose values the
                requester is interested. If the client omits this
                attribute, the server responds as if this attribute
                had been supplied with a value of 'all'.
            'requested-user-name' (name(127)) : CUPS 1.2/Mac OS X 10.5
                The client OPTIONALLY supplies a user name that is
                used to filter the returned printers.

        CUPS-Get-Printers Response
        --------------------------

        The following groups of attributes are send as part of the
        CUPS-Get-Printers Response:

        Group 1: Operation Attributes
            Status Message:
                The standard response status message.
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.2 of the IPP Model and Semantics
                document.
                
        Group 2: Printer Object Attributes
            The set of requested attributes and their current values
            for each printer.

        (Source: http://www.cups.org/documentation.php/spec-ipp.html#CUPS_GET_PRINTERS )
            
        """

        # Each printer will append a new printer attribute group.
        for printer in self.printers:
            self._get_printer_attributes(self.printers[printer], request, response)

    @handler_for(const.Operations.CUPS_GET_CLASSES)
    def cups_get_classes(self, request, response):
        """The CUPS-Get-Classes operation (0x4005) returns the printer
        attributes for every printer class known to the system. This
        may include printer classes that are not served directly by
        the server.

        CUPS-Get-Classes Request
        ------------------------

        The following groups of attributes are supplied as part of the
        CUPS-Get-Classes request:

        Group 1: Operation Attributes
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.1 of the IPP Model and Semantics
                document.
            'first-printer-name' (name(127)):CUPS 1.2/Mac OS X 10.5
                The client OPTIONALLY supplies this attribute to
                select the first printer that is returned.
            'limit' (integer (1:MAX)):
                The client OPTIONALLY supplies this attribute limiting
                the number of printer classes that are returned.
            'printer-location' (text(127)): CUPS 1.1.7
                The client OPTIONALLY supplies this attribute to
                select which printer classes are returned.
            'printer-type' (type2 enum): CUPS 1.1.7
                The client OPTIONALLY supplies a printer type
                enumeration to select which printer classes are
                returned.
            'printer-type-mask' (type2 enum): CUPS 1.1.7
                The client OPTIONALLY supplies a printer type mask
                enumeration to select which bits are used in the
                'printer-type' attribute.
            'requested-attributes' (1setOf keyword) :
                The client OPTIONALLY supplies a set of attribute
                names and/or attribute group names in whose values the
                requester is interested. If the client omits this
                attribute, the server responds as if this attribute
                had been supplied with a value of 'all'.
            'requested-user-name' (name(127)) : CUPS 1.2/Mac OS X 10.5
                The client OPTIONALLY supplies a user name that is
                used to filter the returned printers.
                
        CUPS-Get-Classes Response
        -------------------------

        The following groups of attributes are send as part of the
        CUPS-Get-Classes Response:

        Group 1: Operation Attributes
            Status Message:
                The standard response status message.
            Natural Language and Character Set:
                The 'attributes-charset' and
                'attributes-natural-language' attributes as described
                in section 3.1.4.2 of the IPP Model and Semantics
                document.

        Group 2: Printer Class Object Attributes
            The set of requested attributes and their current values
            for each printer class.

        (Source: http://www.cups.org/documentation.php/spec-ipp.html#CUPS_GET_CLASSES )

        """
        
        # We have no printer classes, so we don't need to do anything
        pass