Merge pull request #300 from ral-facilities/feature/icat-to-panosc-da…

…ta-model-conversion-#265

ICAT to PaNOSC Data Model Conversion

datagateway_api/search_api_mapping.json.example

@@ -65,10 +65,10 @@
     "Parameter": {
         "base_icat_entity": ["InvestigationParameter", "DatasetParameter"],
         "id": "id",
-        "name": "name",
+        "name": "type.name",
         "value": ["numericValue", "stringValue", "dateTimeValue"],
         "unit": "type.units",
-        "dataset": {"Dataset": "investigation.investigationInstruments.instrument.datasetInstruments.dataset"},
+        "dataset": {"Dataset": "dataset"},
         "document": {"Document": "investigation"}
     },
     "Person": {

datagateway_api/src/search_api/filters.py

@@ -3,7 +3,6 @@
 import logging
 
 from datagateway_api.src.common.date_handler import DateHandler
-from datagateway_api.src.common.exceptions import FilterError
 from datagateway_api.src.datagateway_api.icat.filters import (
     PythonICATIncludeFilter,
     PythonICATLimitFilter,
@@ -15,9 +14,6 @@
 
 log = logging.getLogger()
 
-# TODO - Implement each of these filters for Search API, inheriting from the Python ICAT
-# versions
-
 
 class SearchAPIWhereFilter(PythonICATWhereFilter):
     def __init__(self, field, value, operation, search_api_query=None):
@@ -42,9 +38,28 @@ def apply_filter(self, query):
 
         # Convert PaNOSC field names to ICAT field names
         for field_name in panosc_field_names:
-            panosc_mapping_name, icat_field_name = self.get_icat_mapping(
+            panosc_mapping_name, icat_field_name = mappings.get_icat_mapping(
                 panosc_mapping_name, field_name,
             )
+
+            # An edge case for ICAT has been somewhat hardcoded here, to deal with
+            # ICAT's different parameter value field names. The following mapping is
+            # assumed (where order matters):
+            # {"Parameter": {"value": ["numericValue", "stringValue", "dateTimeValue"]}}
+            if isinstance(icat_field_name, list):
+                if isinstance(self.value, int) or isinstance(self.value, float):
+                    icat_field_name = icat_field_name[0]
+                elif isinstance(self.value, datetime):
+                    icat_field_name = icat_field_name[2]
+                elif isinstance(self.value, str):
+                    if DateHandler.is_str_a_date(self.value):
+                        icat_field_name = icat_field_name[2]
+                    else:
+                        icat_field_name = icat_field_name[1]
+                else:
+                    self.value = str(self.value)
+                    icat_field_name = icat_field_name[1]
+
             icat_field_names.append(icat_field_name)
 
         log.debug(
@@ -60,68 +75,6 @@ def apply_filter(self, query):
 
         return super().apply_filter(query.icat_query.query)
 
-    def get_icat_mapping(self, panosc_entity_name, field_name):
-        """
-        This function searches the PaNOSC mappings (from `search_api_mapping.json`,
-        maintained/stored by :class:`PaNOSCMappings`) and retrieves the ICAT translation
-        from the PaNOSC input. Fields in the same entity can be found, as well as fields
-        from related entities (e.g. Dataset.files.path) via recursion inside this
-        function.
-
-        An edge case for ICAT has been somewhat hardcoded into this function to dea
-        with ICAT's different parameter value field names. The following mapping is
-        assumed (where order matters):
-        {"Parameter": {"value": ["numericValue", "stringValue", "dateTimeValue"]}}
-
-        :param panosc_entity_name: A PaNOSC entity name e.g. "Dataset"
-        :type panosc_entity_name: :class:`str`
-        :param field_name: PaNOSC field name to fetch the ICAT version of e.g. "name"
-        :type field_name: :class:`str`
-        :return: Tuple containing the PaNOSC entity name (which will change from the
-            input if a related entity is found) and the ICAT field name
-            mapping/translation from the PaNOSC data model
-        :raises FilterError: If a valid mapping cannot be found
-        """
-
-        log.info(
-            "Searching mapping file to find ICAT translation for %s",
-            f"{panosc_entity_name}.{field_name}",
-        )
-
-        try:
-            icat_mapping = mappings.mappings[panosc_entity_name][field_name]
-            log.debug("ICAT mapping/translation found: %s", icat_mapping)
-        except KeyError as e:
-            raise FilterError(f"Bad PaNOSC to ICAT mapping: {e.args}")
-
-        if isinstance(icat_mapping, str):
-            # Field name
-            icat_field_name = icat_mapping
-        elif isinstance(icat_mapping, dict):
-            # Relation - JSON format: {PaNOSC entity name: ICAT related field name}
-            panosc_entity_name = list(icat_mapping.keys())[0]
-            icat_field_name = icat_mapping[panosc_entity_name]
-        elif isinstance(icat_mapping, list):
-            # Edge case for ICAT's different parameter value field names
-            if isinstance(self.value, int) or isinstance(self.value, float):
-                icat_field_name = icat_mapping[0]
-            elif isinstance(self.value, datetime):
-                icat_field_name = icat_mapping[2]
-            elif isinstance(self.value, str):
-                if DateHandler.is_str_a_date(self.value):
-                    icat_field_name = icat_mapping[2]
-                else:
-                    icat_field_name = icat_mapping[1]
-            else:
-                self.value = str(self.value)
-                icat_field_name = icat_mapping[1]
-
-        log.debug(
-            "Output of get_icat_mapping(): %s, %s", panosc_entity_name, icat_field_name,
-        )
-
-        return panosc_entity_name, icat_field_name
-
     def __str__(self):
         """
         String representation which is also used to apply WHERE filters that are inside
@@ -179,8 +132,33 @@ def apply_filter(self, query):
 
 
 class SearchAPIIncludeFilter(PythonICATIncludeFilter):
-    def __init__(self, included_filters):
+    def __init__(self, included_filters, panosc_entity_name):
+        self.included_filters = included_filters
+        self.panosc_entity_name = panosc_entity_name
         super().__init__(included_filters)
 
     def apply_filter(self, query):
+        icat_field_names = []
+
+        for panosc_field_name in self.included_filters:
+            # Need an empty list at start of each iteration to clear field names from
+            # previous iterations
+            split_icat_field_name = []
+
+            panosc_entity_name = self.panosc_entity_name
+            split_panosc_fields = panosc_field_name.split(".")
+
+            for split_field in split_panosc_fields:
+                panosc_entity_name, icat_field_name = mappings.get_icat_mapping(
+                    panosc_entity_name, split_field,
+                )
+                split_icat_field_name.append(icat_field_name)
+
+            icat_field_names.append(".".join(split_icat_field_name))
+
+        # All PaNOSC field names translated to ICAT, so we can overwrite the PaNOSC
+        # versions with the ICAT mappings so they can be used to apply the filter via
+        # `super().apply_filter()`
+        self.included_filters = icat_field_names
+
         return super().apply_filter(query.icat_query.query)