Allow simulation customization in web API

CHANGELOG.md

@@ -1,5 +1,20 @@
 # Changelog
 
+## 41.6.0 [#1204](https://github.com/openfisca/openfisca-core/pull/1204)
+
+#### New feature
+
+- Introduce `simulation_configurator`
+  - Allow simulation customization in web API
+
+```python
+def simulation_configurator(simulation):
+    simulation.max_spiral_loops = 4
+
+application = create_app(tax_benefit_system,
+    simulation_configurator=simulation_configurator)
+```
+
 ## 41.5.0 [#1205](https://github.com/openfisca/openfisca-core/pull/1205)
 
 #### New feature

openfisca_web_api/app.py

@@ -5,7 +5,7 @@
 import traceback
 
 from openfisca_core.errors import PeriodMismatchError, SituationParsingError
-from openfisca_web_api import handlers
+from openfisca_web_api.handlers import Handler
 from openfisca_web_api.errors import handle_import_error
 from openfisca_web_api.loader import build_data
 
@@ -49,6 +49,7 @@ def init_tracker(url, idsite, tracker_token):
 
 def create_app(
     tax_benefit_system,
+    simulation_configurator=None,
     tracker_url=None,
     tracker_idsite=None,
     tracker_token=None,
@@ -60,6 +61,8 @@ def create_app(
         tracker = init_tracker(tracker_url, tracker_idsite, tracker_token)
 
     app = Flask(__name__)
+    handlers = Handler(simulation_configurator)
+
     # Fix request.remote_addr to get the real client IP address
     app.wsgi_app = ProxyFix(app.wsgi_app, x_for=1, x_host=1)
     CORS(app, origins="*")

openfisca_web_api/handlers.py

@@ -6,84 +6,94 @@
 from openfisca_core.simulation_builder import SimulationBuilder
 
 
-def calculate(tax_benefit_system, input_data: dict) -> dict:
-    """
-    Returns the input_data where the None values are replaced by the calculated values.
-    """
-    simulation = SimulationBuilder().build_from_entities(tax_benefit_system, input_data)
-    requested_computations = dpath.util.search(
-        input_data, "*/*/*/*", afilter=lambda t: t is None, yielded=True
-    )
-    computation_results: dict = {}
-    for computation in requested_computations:
-        path = computation[
-            0
-        ]  # format: entity_plural/entity_instance_id/openfisca_variable_name/period
-        entity_plural, entity_id, variable_name, period = path.split("/")
-        variable = tax_benefit_system.get_variable(variable_name)
-        result = simulation.calculate(variable_name, period)
-        population = simulation.get_population(entity_plural)
-        entity_index = population.get_index(entity_id)
-
-        if variable.value_type == Enum:
-            entity_result = result.decode()[entity_index].name
-        elif variable.value_type == float:
-            entity_result = float(
-                str(result[entity_index])
-            )  # To turn the float32 into a regular float without adding confusing extra decimals. There must be a better way.
-        elif variable.value_type == str:
-            entity_result = str(result[entity_index])
-        else:
-            entity_result = result.tolist()[entity_index]
-        # Don't use dpath.util.new, because there is a problem with dpath>=2.0
-        # when we have a key that is numeric, like the year.
-        # See https://github.com/dpath-maintainers/dpath-python/issues/160
-        if computation_results == {}:
-            computation_results = {
-                entity_plural: {entity_id: {variable_name: {period: entity_result}}}
-            }
+class Handler(object):
+    def __init__(self, simulation_configurator=None):
+        super(Handler, self).__init__()
+        if simulation_configurator:
+            self.simulation_configurator = simulation_configurator
         else:
-            if entity_plural in computation_results:
-                if entity_id in computation_results[entity_plural]:
-                    if variable_name in computation_results[entity_plural][entity_id]:
-                        computation_results[entity_plural][entity_id][variable_name][
-                            period
-                        ] = entity_result
+            self.simulation_configurator = lambda x: x
+
+    def calculate(self, tax_benefit_system, input_data: dict) -> dict:
+        """
+        Returns the input_data where the None values are replaced by the calculated values.
+        """
+        simulation = SimulationBuilder().build_from_entities(tax_benefit_system, input_data)
+        self.simulation_configurator(simulation)
+
+        requested_computations = dpath.util.search(
+            input_data, "*/*/*/*", afilter=lambda t: t is None, yielded=True
+        )
+        computation_results: dict = {}
+        for computation in requested_computations:
+            path = computation[
+                0
+            ]  # format: entity_plural/entity_instance_id/openfisca_variable_name/period
+            entity_plural, entity_id, variable_name, period = path.split("/")
+            variable = tax_benefit_system.get_variable(variable_name)
+            result = simulation.calculate(variable_name, period)
+            population = simulation.get_population(entity_plural)
+            entity_index = population.get_index(entity_id)
+
+            if variable.value_type == Enum:
+                entity_result = result.decode()[entity_index].name
+            elif variable.value_type == float:
+                entity_result = float(
+                    str(result[entity_index])
+                )  # To turn the float32 into a regular float without adding confusing extra decimals. There must be a better way.
+            elif variable.value_type == str:
+                entity_result = str(result[entity_index])
+            else:
+                entity_result = result.tolist()[entity_index]
+            # Don't use dpath.util.new, because there is a problem with dpath>=2.0
+            # when we have a key that is numeric, like the year.
+            # See https://github.com/dpath-maintainers/dpath-python/issues/160
+            if computation_results == {}:
+                computation_results = {
+                    entity_plural: {entity_id: {variable_name: {period: entity_result}}}
+                }
+            else:
+                if entity_plural in computation_results:
+                    if entity_id in computation_results[entity_plural]:
+                        if variable_name in computation_results[entity_plural][entity_id]:
+                            computation_results[entity_plural][entity_id][variable_name][
+                                period
+                            ] = entity_result
+                        else:
+                            computation_results[entity_plural][entity_id][variable_name] = {
+                                period: entity_result
+                            }
                     else:
-                        computation_results[entity_plural][entity_id][variable_name] = {
-                            period: entity_result
+                        computation_results[entity_plural][entity_id] = {
+                            variable_name: {period: entity_result}
                         }
                 else:
-                    computation_results[entity_plural][entity_id] = {
-                        variable_name: {period: entity_result}
+                    computation_results[entity_plural] = {
+                        entity_id: {variable_name: {period: entity_result}}
                     }
-            else:
-                computation_results[entity_plural] = {
-                    entity_id: {variable_name: {period: entity_result}}
-                }
-    dpath.util.merge(input_data, computation_results)
-
-    return input_data
+        dpath.util.merge(input_data, computation_results)
 
+        return input_data
 
-def trace(tax_benefit_system, input_data):
-    simulation = SimulationBuilder().build_from_entities(tax_benefit_system, input_data)
-    simulation.trace = True
+    def trace(self, tax_benefit_system, input_data):
+        simulation = SimulationBuilder().build_from_entities(tax_benefit_system, input_data)
+        self.simulation_configurator(simulation)
+        simulation.trace = True
 
-    requested_calculations = []
-    requested_computations = dpath.util.search(
-        input_data, "*/*/*/*", afilter=lambda t: t is None, yielded=True
-    )
-    for computation in requested_computations:
-        path = computation[0]
-        entity_plural, entity_id, variable_name, period = path.split("/")
-        requested_calculations.append(f"{variable_name}<{str(period)}>")
-        simulation.calculate(variable_name, period)
+        requested_calculations = []
+        requested_computations = dpath.util.search(
+            input_data, "*/*/*/*", afilter=lambda t: t is None, yielded=True
+        )
+        for computation in requested_computations:
+            path = computation[0]
+            entity_plural, entity_id, variable_name, period = path.split("/")
+            requested_calculations.append(f"{variable_name}<{str(period)}>")
+            simulation.calculate(variable_name, period)
 
-    trace = simulation.tracer.get_serialized_flat_trace()
+        trace = simulation.tracer.get_serialized_flat_trace()
 
-    return {
-        "trace": trace,
-        "entitiesDescription": simulation.describe_entities(),
-        "requestedCalculations": requested_calculations,
-    }
+        return {
+            "trace": trace,
+            "entitiesDescription": simulation.describe_entities(),
+            "requestedCalculations": requested_calculations,
+        }

openfisca_web_api/loader/spec.py

@@ -7,12 +7,14 @@
 import yaml
 
 from openfisca_core.indexed_enums import Enum
-from openfisca_web_api import handlers
+from openfisca_web_api.handlers import Handler
 
 OPEN_API_CONFIG_FILE = os.path.join(
     os.path.dirname(os.path.abspath(__file__)), os.path.pardir, "openAPI.yml"
 )
 
+handlers = Handler()
+
 
 def build_openAPI_specification(api_data):
     tax_benefit_system = api_data["tax_benefit_system"]

setup.py

@@ -67,7 +67,7 @@
 
 setup(
     name="OpenFisca-Core",
-    version="41.5.0",
+    version="41.6.0",
     author="OpenFisca Team",
     author_email="contact@openfisca.org",
     classifiers=[