new paged approach for data handling

data/src/entity_manager/system.py

@@ -2338,24 +2338,12 @@ def count(self, entity_class, options = None, lock = False, **kwargs):
         return result
 
     def find(self, entity_class, options = {}, lock = False, **kwargs):
-        # retrieves the start record and the number of records so that
-        # it's possible to infer if the current request is going to be
-        # paged or if a typical (eager) retrieval should be performed
-        start_record = options.get("start_record", 0)
-        number_records = options.get("number_records", 0)
-        allow_paged = options.get("paged", False)
-
-        # calculates the total number of records to be retrieved and
-        # then used the target page size calculates the number of pages
-        # and verifies if the requested should be paged or not
-        record_count = number_records - start_record
-        page_count = int(math.ceil(record_count / float(PAGE_SIZE)))
-        is_paged = page_count > 1 and allow_paged
-
-        # in case this is a paging situation the proper paging handler
+        # verifies if the current find operation is meant to be paged
+        # in case that's the request approach the proper paging handler
         # must be used so that the values are properly yielded allowing
         # a lazy base evaluation of the values from the entity manager
-        if is_paged: return self.page(
+        paged = options.get("paged", False)
+        if paged: return self.page(
             entity_class,
             options = options,
             lock = lock,
@@ -2422,6 +2410,7 @@ def page(self, entity_class, options = {}, lock = False, **kwargs):
         # that is going to be changed for each iteration and then
         # initializes the current record value with the start record
         _options = dict(options)
+        _options["paged"] = False
         current_record = start_record
 
         # iterates over the complete set of pages for the data set

mvc/src/mvc_utils/entity_model.py

@@ -739,6 +739,7 @@ def _class_create_filter(cls, data, defaults = {}, entity_manager = None):
     name = defaults.get("name", None)
     type_s = defaults.get("type", "both")
     order_by = defaults.get("order_by", None)
+    paged = defaults.get("paged", False)
     eager = defaults.get("eager", ())
     allowed = defaults.get("allowed", ())
     filters = defaults.get("filters", [])
@@ -748,6 +749,7 @@ def _class_create_filter(cls, data, defaults = {}, entity_manager = None):
     # defaulting to the pre-defined default values
     filter_string = data.get("filter_string", "")
     sort = data.get("sort", None)
+    paged_s = data.get("paged", "0")
     eager_s = data.get("eager", [])
     filters_s = data.get("filters", [])
     start_record = data.get("start_record", 0)
@@ -769,6 +771,10 @@ def _class_create_filter(cls, data, defaults = {}, entity_manager = None):
     sort_value, sort_order = sort and sort.split(":", 1) or ("default", None)
     order_by = not sort_value == "default" and ((sort_value, sort_order),) or order_by
 
+    # tries to retrieve the proper value for the paged element
+    # taking into account a possible boolean approach
+    paged = True if paged_s == "1" else False
+
     def eager_r(eager_s):
         # in case the eager sequence is not valid or empty
         # or if the data type of the eager structure is not
@@ -933,6 +939,7 @@ def resolve_s(attribute):
     filter = dict(
         range = (start_record, number_records),
         order_by = order_by or (),
+        paged = paged,
         eager = eager,
         filters = filters,
         map = map