bag.interface.server

This class defines SkillOceanServer, a server that handles skill/ocean requests.

The SkillOceanServer listens for skill/ocean requests from bag. Skill commands will be forwarded to Virtuoso for execution, and Ocean simulation requests will be handled by starting an Ocean subprocess. It also provides utility for bag to query simulation progress and allows parallel simulation.

Client-side communication:

the client will always send a request object, which is a python dictionary. This script processes the request and sends the appropriate commands to Virtuoso.

Virtuoso side communication:

To ensure this process receive all the data from Virtuoso properly, Virtuoso will print a single line of integer indicating the number of bytes to read. Then, virtuoso will print out exactly that many bytes of data, followed by a newline (to flush the standard input). This script handles that protcol and will strip the newline before sending result back to client.

Module Contents

Classes

SkillServer

A server that handles skill commands.

Functions

_object_to_skill_file_helper(py_obj, file_obj)	Recursive helper function for object_to_skill_file
object_to_skill_file(py_obj, file_obj)	Write the given python object to a file readable by Skill.

Attributes

bag_proc_prompt

bag.interface.server._object_to_skill_file_helper(py_obj, file_obj)

Recursive helper function for object_to_skill_file

Parameters:

• py_obj (any) – the object to convert.

• file_obj (file) – the file object to write to. Must be created with bag.io package so that encodings are handled correctly.

bag.interface.server.object_to_skill_file(py_obj, file_obj)

Write the given python object to a file readable by Skill.

Write a Python object to file that can be parsed into equivalent skill object by Virtuoso. Currently only strings, lists, and dictionaries are supported.

Parameters:

• py_obj (any) – the object to convert.

• file_obj (file) – the file object to write to. Must be created with bag.io package so that encodings are handled correctly.

bag.interface.server.bag_proc_prompt = 'BAG_PROMPT>>> '

class bag.interface.server.SkillServer(router, virt_in, virt_out, tmpdir=None)

Bases: object

A server that handles skill commands.

This server is started and ran by virtuoso. It listens for commands from bag from a ZMQ socket, then pass the command to virtuoso. It then gather the result and send it back to bag.

Parameters:

• router (bag.interface.ZMQRouter) – the ZMQRouter object used for socket communication.

• virt_in (file) – the virtuoso input file. Must be created with bag.io package so that encodings are handled correctly.

• virt_out (file) – the virtuoso output file. Must be created with bag.io package so that encodings are handled correctly.

• tmpdir (str or None) – if given, will save all temporary files to this folder.

run()

Starts this server.

send_skill(expr)

Sends expr to virtuoso for evaluation.

Parameters:

expr (string) – the skill expression.

recv_skill()

Receive response from virtuoso

close()

Close this server.

process_skill_request(request)

Process the given skill request.

Based on the given request object, returns the skill expression to be evaluated by Virtuoso. This method creates temporary files for long input arguments and long output.

Parameters:

request (dict) – the request object.

Returns:

• expr (str or None) – expression to be evaluated by Virtuoso. If None, an error occurred and nothing needs to be evaluated

• out_file (str or None) – if not None, the result will be written to this file.

process_skill_result(msg, out_file=None)

Process the given skill output, then send result to socket.

Parameters:

• msg (str) – skill expression evaluation output.

• out_file (str or None) – if not None, read result from this file.