irt-service/app/services/loft_service.py

201 lines
8.5 KiB
Python

import os, json, random, io, logging
from pulp import LpProblem, LpVariable, LpMinimize, LpMaximize, LpAffineExpression, LpConstraint, LpStatus, lpSum
from helpers import aws_helper, tar_helper, csv_helper, service_helper, solver_helper
from lib.errors.item_generation_error import ItemGenerationError
from models.solver_run import SolverRun
from models.solution import Solution
from models.form import Form
from models.item import Item
from services.base import Base
class LoftService(Base):
def process(self):
try:
self.solver_run = self.create_solver_run_from_attributes()
self.solver_run.generate_bundles()
self.solution = self.generate_solution()
self.result = self.stream_to_s3_bucket()
except ItemGenerationError as error:
self.result = self.stream_to_s3_bucket(error)
except TypeError as error:
logging.error(error)
self.result = self.stream_to_s3_bucket(
ItemGenerationError(
"Provided params causing error in calculation results"))
def create_solver_run_from_attributes(self) -> SolverRun:
logging.info('Retrieving attributes from message...')
# get s3 object
self.key = aws_helper.get_key_from_message(self.source)
s3_object = aws_helper.get_object(
self.key, aws_helper.get_bucket_from_message(self.source))
# convert to tar
self.tar = tar_helper.raw_to_tar(s3_object)
# get attributes file and convert to dict
attributes = json.loads(
tar_helper.extract_file_from_tar(
self.tar, 'solver_run_attributes.json').read())
# create solver run
solver_run = SolverRun.parse_obj(attributes)
# get items file and convert to dict
items_csv = tar_helper.extract_file_from_tar(self.tar, 'items.csv')
items_csv_reader = csv_helper.file_stream_reader(items_csv)
# add items to solver run
for item in service_helper.items_csv_to_dict(items_csv_reader,
solver_run):
solver_run.items.append(Item.parse_obj(item))
logging.info('Processed Attributes...')
return solver_run
def generate_solution(self) -> Solution:
logging.info('Generating Solution...')
solution = Solution(response_id=random.randint(100, 5000), forms=[]) # unsolved solution
# setup common Solver variables
items = LpVariable.dicts("Item", [item.id for item in self.solver_run.items], cat='Binary')
bundles = LpVariable.dicts("Bundle", [bundle.id for bundle in self.solver_run.bundles], cat='Binary')
form_count = 0 # counter for number of forms
# iterate for number of forms that require creation
while form_count < self.solver_run.total_forms:
form_number = form_count + 1
logging.info('Generating Solution for Form %s...', form_number)
# create problem
problem = LpProblem("ata-form-generate", LpMinimize)
problem_objective_functions = []
# dummy objective function, because it just makes things easier™
problem += lpSum([items[item.id] for item in self.solver_run.items])
# constraints
problem += lpSum([items[item.id]
for item in self.solver_run.items]) == self.solver_run.total_form_items, f'Total form items for form {form_number}'
problem += lpSum(
[
bundle.count * bundles[bundle.id]
for bundle in self.solver_run.bundles
] + [
1 * items[item.id]
for item in self.solver_run.unbundled_items()
]
) == self.solver_run.total_form_items, f'Total bundle form items for form {form_number}'
# Dynamic constraints.. currently we only support Metadata and Bundles(Cases/Passages)
problem = solver_helper.build_constraints(self.solver_run, problem, items, bundles)
# multi-objective constraints
logging.info('Creating TIF and TCC constraints')
for target in self.solver_run.objective_function.tif_targets:
tif = lpSum([
bundle.tif(self.solver_run.irt_model, target.theta) *
bundles[bundle.id] for bundle in self.solver_run.bundles
] + [
item.iif(self.solver_run, target.theta) * items[item.id]
for item in self.solver_run.items
]) <= target.value, f'min tif theta {target.theta} target for form {form_number}'
problem += tif
problem_objective_functions.append(tif)
e = LpAffineExpression(
[(bundles[bundle.id],
bundle.tif(self.solver_run.irt_model, target.theta))
for bundle in self.solver_run.bundles] +
[(items[item.id], item.iif(self.solver_run, target.theta))
for item in self.solver_run.items])
constraint = LpConstraint(
e=e,
sense=0,
name=f'tif theta ({target.theta}) @{target.value}',
rhs=target.value)
elasticized_constraint = solver_helper.elasticize_constraint(constraint)
problem.extend(elasticized_constraint)
# if int(target.value) == 20: print(elasticized_constraint)
for target in self.solver_run.objective_function.tcc_targets:
tcc = lpSum([
bundle.trf(self.solver_run.irt_model, target.theta) *
bundles[bundle.id] for bundle in self.solver_run.bundles
] + [
item.irf(self.solver_run, target.theta) * items[item.id]
for item in self.solver_run.items
]) <= target.value, f'min tcc theta {target.theta} target for form {form_number}'
problem += tcc
problem_objective_functions.append(tcc)
e = LpAffineExpression(
[(bundles[bundle.id],
bundle.trf(self.solver_run.irt_model, target.theta))
for bundle in self.solver_run.bundles] +
[(items[item.id], item.irf(self.solver_run, target.theta))
for item in self.solver_run.items])
constraint = LpConstraint(
e=e,
sense=-1,
name=f'tcc theta ({target.theta}) @{target.value} for form {form_number}',
rhs=target.value)
elasticized_constraint = solver_helper.elasticize_constraint(constraint)
# problem.extend(elasticized_constraint)
# solve problem
logging.info('Solving for Form %s...', form_number)
print(problem)
problem.solve()
# problem.sequentialSolve(problem_objective_functions)
logging.info(f'Solved for Form {form_number}...generating form and adding to solution')
# add return items and create as a form
form_items = service_helper.solution_items(problem.variables(), self.solver_run)
# add form to solution
solution.forms.append(Form.create(form_items, self.solver_run, LpStatus[problem.status]))
logging.info('Form generated and added to solution...')
# successfull form, increment
form_count += 1
logging.info('Solution Generated.')
# print(problem)
return solution
def stream_to_s3_bucket(self, error=None):
self.file_name = f'{service_helper.key_to_uuid(self.key)}.csv'
solution_file = None
# setup writer buffer and write processed forms to file
buffer = io.StringIO()
if error:
logging.info('Streaming %s error response to s3 bucket - %s',
self.file_name, os.environ['S3_PROCESSED_BUCKET'])
solution_file = service_helper.error_to_file(buffer, error)
else:
logging.info('Streaming %s to s3 bucket - %s', self.file_name,
os.environ['S3_PROCESSED_BUCKET'])
solution_file = service_helper.solution_to_file(
buffer, self.solver_run.total_form_items, self.solution.forms)
# upload generated file to s3 and return result
return aws_helper.file_stream_upload(solution_file, self.file_name,
os.environ['S3_PROCESSED_BUCKET'])