F dict heuristic

Summary

Part of https://gitlab.indiscale.com/caosdb/customers/3dmmto/management/-/issues/30. Introduce a converter that automatically transforms dictionary entries to property values without having to specify them explicitly. It also also creates referenced Records from object-typed dictionary values. Properties can be blacklisted.

The new converter extends the existing DictElementConverter, so we can still use the existing treatment via records and subtree entries in the converter definition. This allows for the special treatment of blacklisted dictionary keys, but it is not limited to them. We do not change the original create_children method, so all dictionary entries are also available in the subtree if needed elsewhere.

Focus

Mainly the new converter and its documentation.

Test Environment

make doc and check the new documentation. Is it understandable? Is it useful?

For actual testing the new unit test should be sufficient. Can you think of corner cases that they do not cover yet?

Check List for the Author

Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related issues
• Up-to-date CHANGELOG.md (or not necessary)
• Up-to-date JSON schema (or not necessary)
• Appropriate user and developer documentation (or not necessary)
  • How do I use the software? Assume "stupid" users.
  • How do I develop or debug the software? Assume novice developers.
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• Appropriate user and developer documentation (or not necessary)
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?

For further good practices have a look at our review guidelines.

src/caoscrawler/cfood-schema.yml

 cfood:
   type: object
+  properties:
+    Converters:
+      description: Defintiion of custom converters
+      type: object
+      additionalProperties:
+        type: object
+        properties:
+          converter:
+            type: string
+          package:
+            type: string
+        required:
+          - converter
+          - package
+    macros:
+      description: Macro definitions
+      type: array
+    Transformers:
+      description: Variable transformer definition
+      type: object
+      additionalProperties:
+        type: object
+        properties:
+          function:
+            type: string
+          package:
+            type: string
+        required:
+          - package
+          - function
   additionalProperties:
     $ref:
       "#/$defs/converter"
   $defs:
+    parents:
+      description: Parents for this record are given here as a list of names.
+      type: array
+      items:
+        type: string
     converter:
       properties:
         type:
@@ -38,6 +73,7 @@ cfood:
           - H5Dataset
           - H5Group
           - H5Ndarray
+          - PropertiesFromDictElement
           description: Type of this converter node.
         match:
           description: typically a regexp which is matched to a structure element name
@@ -48,15 +84,42 @@ cfood:
         match_value:
           description: a regexp that is matched to the value of a key-value pair
           type: string
-        records:
-          description: This field is used to define new records or to modify records which have been defined on a higher level.
+        record_from_dict:
+          description: Only relevant for PropertiesFromDictElement.  Specify the root record which is generated from the contained dictionary.
           type: object
+          required:
+            - variable_name
           properties:
-            parents:
-              description: Parents for this record are given here as a list of names.
+            variable_name:
+              description: Name of the record by which it can be accessed in the cfood definiton. Can also be the name of an existing record in which case that record will be treated by the PropertiesFromDictConverter.
+              type: string
+            properties_blacklist:
+              description: List of keys to be ignored in the automatic treatment.  They will be ignored on all levels of the dictionary.
               type: array
               items:
                 type: string
+            references:
+              description: List of keys that will be transformed into named reference properties.
+              type: object
+              additionalProperties:
+                type: object
+                properties:
+                  parents:
+                    $ref:
+                      "#/$defs/parents"
+            name:
+              description: Nmae of this record.  If none is given, variable_name is used.
+              type: string
+            parents:
+              $ref:
+                "#/$defs/parents"
+        records:
+          description: This field is used to define new records or to modify records which have been defined on a higher level.
+          type: object
+          properties:
+            parents:
+              $ref:
+                "#/$defs/parents"
             additionalProperties:
               oneOf:
               - type: object
@@ -78,3 +141,15 @@ cfood:
           additionalProperties:
             $ref:
               "#/$defs/converter"
+      if:
+        properties:
+          type:
+            const:
+              "PropertiesFromDictElement"
+      then:
+        required:
+          - type
+          - record_from_dict
+      else:
+        required:
+          - type