globus_gram_protocol(3) 				       globus gram protocol					   globus_gram_protocol(3)

NAME

       globus_gram_protocol - GRAM Protocol Definition The GRAM Protocol is used to handle communication between the Gatekeeper, Job Manager, and
       GRAM Clients.

       The protocol is based on a subset of the HTTP/1.1 protocol, with a small set of message types and responses sent as the body of the HTTP
       requests and responses. This document describes GRAM Protocol version 2.

   Framing
       GRAM messages are framed in HTTP/1.1 messages. However, only a small subset of the HTTP specification is used or understood by the GRAM
       system. All GRAM requests are HTTP POST messages. Only the following HTTP headers are understood:

       o Host

       o Content-Type (set to 'application/x-globus-gram' in all cases)

       o Content-Length

       o Connection (set to 'close' in all HTTP responses)

       Only the following status codes are supported in response's HTTP Status-Lines:

       o 200 OK

       o 403 Forbidden

       o 404 Not Found

       o 500 Internal Server Error

       o 400 Bad Request

   Message Format
       All messages use the carriage return (ASCII value 13) followed by line feed (ASCII value 10) sequence to delimit lines. In all cases, a
       blank line separates the HTTP header from the message body. All application/x-globus-gram message bodies consist of attribute names
       followed by a colon, a space, and then the value of the attribute. When the value may contain a newline or double-quote character, a
       special escaping rule is used to encapsulate the complete string. This encapsulation consists of surrounding the string with double-quotes,
       and escaping all double-quote and backslash characters within the string with a backslash. All other characters are sent without
       modification. For example, the string

       rsl: &( executable = '/bin/echo' )
	( arguments = 'hello' )

	becomes

       rsl: '&( executable = 'bin/echo' )
	 (arguments = 'hello' )'

       This is the only form of quoting which application/x-globus-gram messages support. Use of % HEX HEX escapes (such as seen in URL encodings)
       is not meaningful for this protocol.

   Message Types
   Ping Request
       A ping request is used to verify that the gatekeeper is configured properly to handle a named service. The ping request consists of the
       following:

	   POST ping/job-manager-name HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version

       The values of the message-specific strings are

       job-manager-name
	   The name of the service to have the gatekeeper check. The service name corresponds to one of the gatekeeper's configured grid-services,
	   and is usually of the form 'jobmanager-<em>scheduler-type</em>'.

       host-name
	   The name of the host on which the gatekeeper is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

   Job Request
       A job request is used to scheduler a job remotely using GRAM. The ping request consists of the HTTP framing described above with the
       request-URI consisting of job-manager-name, where job-manager name is the name of the service to use to schedule the job. The format of a
       job request message consists of the following:

	   POST job-manager-name[@user-name] HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   job-state-mask: mask
	   callback-url: callback-contact
	   rsl: rsl-description

       The values of the emphasized text items are as below:

       job-manager-name
	   The name of the service to submit the job request to. The service name corresponds to one of the gatekeeper's configured grid-services,
	   and is usually of the form 'jobmanager-<em>scheduler-type</em>'.

       user-name
	   Starting with GT4.0, a client may request that a certain account by used by the gatekeeper to start the job manager. This is done
	   optionally by appending the @ symbol and the local user name that the job should be run as to the job-manager-name. If the @ and
	   username are not present, then the first grid map entry will be used. If the client credential is not authorized in the grid map to use
	   the specified account, an authorization error will occur in the gatekeeper.

       host-name
	   The name of the host on which the gatekeeper is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

       mask
	   An integer representation of the job state mask. This value is obtained from a bitwise-OR of the job state values which the client
	   wishes to receive job status callbacks about. These meanings of the various job state values are defined in the GRAM Protocol API
	   documentation.

       callback-contact
	   A https URL which defines a GRAM protocol listener which will receive job state updates. The from a bitwise-OR of the job state values
	   which the client wishes to receive job status callbacks about. The job status update messages are defined below.

       rsl-description
	   A quoted string containing the RSL description of the job request.

   Status Request
       A status request is used by a GRAM client to get the current job state of a running job. This type of message can only be sent to a job
       manager's job-contact (as returned in the reply to a job request message). The format of a job request message consists of the following:

	   POST job-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   'status'

       The values of the emphasized text items are as below:

       job-contact
	   The job contact string returned in a response to a job request message, or determined by querying the MDS system.

       host-name
	   The name of the host on which the job manager is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

   Callback Register Request
       A callback register request is used by a GRAM client to register a new callback contact to receive GRAM job state updates. This type of
       message can only be sent to a job manager's job-contact (as returned in the reply to a job request message). The format of a job request
       message consists of the following:

	   POST job-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   'register <em>mask</em> <em>callback-contact</em>'

       The values of the emphasized text items are as below:

       job-contact
	   The job contact string returned in a response to a job request message, or determined by querying the MDS system.

       host-name
	   The name of the host on which the job manager is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

       mask
	   An integer representation of the job state mask. This value is obtained from a bitwise-OR of the job state values which the client
	   wishes to receive job status callbacks about. These meanings of the various job state values are defined in the GRAM Protocol API
	   documentation.

       callback-contact
	   A https URL which defines a GRAM protocol listener which will receive job state updates. The from a bitwise-OR of the job state values
	   which the client wishes to receive job status callbacks about. The job status update messages are defined below.

   Callback Unregister Request
       A callback unregister request is used by a GRAM client to request that the job manager no longer send job state updates to the specified
       callback contact. This type of message can only be sent to a job manager's job-contact (as returned in the reply to a job request message).
       The format of a job request message consists of the following:

	   POST job-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   'unregister <em>callback-contact</em>'

       The values of the emphasized text items are as below:

       job-contact
	   The job contact string returned in a response to a job request message, or determined by querying the MDS system.

       host-name
	   The name of the host on which the job manager is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

       callback-contact
	   A https URL which defines a GRAM protocol listener which should no longer receive job state updates. The from a bitwise-OR of the job
	   state values which the client wishes to receive job status callbacks about. The job status update messages are defined below.

   Job Cancel Request
       A job cancel request is used by a GRAM client to request that the job manager terminate a job. This type of message can only be sent to a
       job manager's job-contact (as returned in the reply to a job request message). The format of a job request message consists of the
       following:

	   POST job-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   'cancel'

       The values of the emphasized text items are as below:

       job-contact
	   The job contact string returned in a response to a job request message, or determined by querying the MDS system.

       host-name
	   The name of the host on which the job manager is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

   Job Signal Request
       A job signal request is used by a GRAM client to request that the job manager process a signal for a job. The arguments to the various
       signals are discussed in the globus_gram_protocol_job_signal_t documentation.

	   POST job-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   '<em>signal</em>'

       The values of the emphasized text items are as below:

       job-contact
	   The job contact string returned in a response to a job request message, or determined by querying the MDS system.

       host-name
	   The name of the host on which the job manager is running. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

       signal
	   A quoted string containing the signal number and it's parameters.

   Job State Updates
       A job status update message is sent by the job manager to all registered callback contacts when the job's status changes. The format of the
       job status update messages is as follows:

	   POST callback-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   job-manager-url: job-contact
	   status: status-code
	   failure-code: failure-code

       The values of the emphasized text items are as below:

       callback-contact
	   The callback contact string registered with the job manager either by being passed as the callback-contact in a job request message or
	   in a callback register message.

       host-name
	   The host part of the callback-contact URL. This exists only for compatibility with the HTTP/1.1 protocol.

       message-size
	   The length of the content of the message, not including the HTTP/1.1 header.

       version
	   The version of the GRAM protocol which is being used. For the protocol defined in this document, the value must be the string '2'.

       job-contact
	   The job contact of the job which has changed states.

   Proxy Delegation
       A proxy delegation message is sent by the client to the job manager to initiate a delegation handshake to generate a new proxy credential
       for the job manager. This credential is used by the job manager or the job when making further secured connections. The format of the
       delegation message is as follows:

	   POST callback-contact HTTP/1.1
	   Host: host-name
	   Content-Type: application/x-globus-gram
	   Content-Length: message-size

	   protocol-version: version
	   'renew'

       If a successful (200) reply is sent in response to this message, then the client will procede with a GSI delegation handshake. The tokens
       in this handshake will be framed with a 4 byte big-endian token length header. The framed tokens will then be wrapped using the
       GLOBUS_IO_SECURE_CHANNEL_MODE_SSL_WRAP wrapping mode. The job manager will frame response tokens in the same manner. After the job manager
       receives its final delegation token, it will respond with another response message that indicates whether the delegation was processed or
       not. This response message is a standard GRAM response message.

   Note on Security Attributes
       The following security attributes are needed to communicate with the Gatekeeper:

       o Authentication must be done using GSSAPI mutual authentication

       o Messages must be wrapped with support for the delegation message. When using Globus I/O, this is accomplished by using the the
	 GLOBUS_IO_SECURE_CHANNEL_MODE_GSI_WRAP wrapping mode.

   Changes
       2004-08-11 Added information about gridmap choosing

Version 11.3							  Mon Apr 30 2012					   globus_gram_protocol(3)