Add first party Objective-C to Swift SDK RPC migration shim. (#350)

stone/backends/obj_c_helpers.py

@@ -151,6 +151,9 @@
     'id',
     'delete',
     'hash',
+    'boolvalue',
+    'floatvalue',
+    'intvalue',
 }
 
 _reserved_prefixes = {

stone/backends/swift_client.py

@@ -31,6 +31,10 @@
     datatype_has_subtypes,
 )
 
+from stone.backends.obj_c_helpers import (
+    fmt_class_prefix
+)
+
 _MYPY = False
 if _MYPY:
     import typing  # noqa: F401 # pylint: disable=import-error,unused-import,useless-suppression
@@ -93,6 +97,11 @@
     action='store_true',
     help='Generate the Objective-C compatibile files.',
 )
+_cmdline_parser.add_argument(
+    '--objc-shim',
+    action='store_true',
+    help='Generate the Objective-C to Swift migration files.',
+)
 
 
 class SwiftBackend(SwiftBaseBackend):
@@ -137,14 +146,23 @@ class SwiftBackend(SwiftBaseBackend):
 
     def generate(self, api):
         for namespace in api.namespaces.values():
-            if namespace.routes:
+            if self._namespace_contains_valid_routes_for_auth_type(namespace):
                 self._generate_routes(namespace)
 
         self._generate_client(api)
         self._generate_request_boxes(api)
-        if not self.args.objc:
+        if not self.args.objc and not self.args.objc_shim:
             self._generate_reconnection_helpers(api)
 
+    # Argument cast when mapping a legacy objc route to an objc route
+    # ', let args = args as? DBUSERSGetAccountBatchArg'
+    def shim_rpc_function_argument_if_necessary(self, data_type):
+        if is_user_defined_type(data_type) and len(data_type.fields) > 0:
+            class_name = fmt_class_prefix(data_type)
+            return ', let args = args as? {}'.format(class_name)
+        else:
+            return ''
+
     def _generate_client(self, api):
         template_globals = {}
         template_globals['class_name'] = self.args.class_name
@@ -158,6 +176,9 @@ def _generate_client(self, api):
 
             self._write_output_in_target_folder(template.render(),
                                                 'DBX{}.swift'.format(self.args.module_name))
+
+        elif self.args.objc_shim:
+            self._generate_sdk_migration_shim(api)
         else:
             template = self._jinja_template("SwiftClient.jinja")
             template.globals = template_globals
@@ -220,6 +241,8 @@ def _generate_routes(self, namespace):
 
             self._write_output_in_target_folder(output_from_parsed_template,
                                                 'DBX{}Routes.swift'.format(ns_class))
+        elif self.args.objc_shim:
+            return
         else:
             template = self._jinja_template("SwiftRoutes.jinja")
             template.globals = template_globals
@@ -258,6 +281,8 @@ def _generate_request_boxes(self, api):
             file_name = 'DBX{}RequestBox.swift'.format(self.args.class_name)
             self._write_output_in_target_folder(output,
                                                 file_name)
+        elif self.args.objc_shim:
+            return
         else:
             template = self._jinja_template("SwiftRequestBox.jinja")
             template.globals = template_globals
@@ -296,6 +321,32 @@ def _generate_reconnection_helpers(self, api):
             output_from_parsed_template, '{}.swift'.format(class_name)
         )
 
+    def _generate_sdk_migration_shim(self, api):
+        template = self._jinja_template("SwiftObjcShimHelpers.jinja")
+        template_globals = {}
+        template_globals['namespaces'] = api.namespaces.values()
+        template_globals['route_client_args'] = self._route_client_args
+        template_globals['fmt_route_objc_class'] = self._fmt_route_objc_class
+        template_globals['fmt_func'] = fmt_func
+        template_globals['fmt_objc_type'] = fmt_objc_type
+        template_globals['objc_to_legacy_objc_mapper'] = self._shim_objc_to_legacy_objc_type_mapper
+        template_globals['fmt_route_name_namespace'] = fmt_route_name_namespace
+        template_globals['shim_rpc_function_arg'] = self.shim_rpc_function_argument_if_necessary
+        template_globals['route_args'] = self._route_args
+        template_globals['is_struct_type'] = is_struct_type
+        template_globals['is_union_type'] = is_union_type
+        template_globals['fmt_var'] = fmt_var
+        objc_init_key = 'shim_legacy_objc_init_args_to_objc'
+        template_globals[objc_init_key] = self._shim_legacy_objc_init_args_to_objc
+        template_globals['fmt_class_prefix'] = fmt_class_prefix
+
+        template.globals = template_globals
+
+        output_from_parsed_template = template.render()
+
+        self._write_output_in_target_folder(output_from_parsed_template,
+                                        'ShimSwiftObjcHelpers.swift')
+
     def _background_compatible_namespace_route_pairs(self, api):
         namespaces = api.namespaces.values()
         background_compatible_routes = []
@@ -557,6 +608,23 @@ def _route_objc_result_type(self, route, args_data):
             result_type = '{}, {}'.format(result_type, error_type)
             return result_type
 
+    # Used in objc to legacy objc type RPC completion mapping, optionals only.
+    # 'mapDBXCameraUploadsMobileCommitCameraUploadResultToDBOptional(object: result)'
+    # 'mapDBXCameraUploadsMobileCommitCameraUploadErrorToDBOptional(object: routeError)'
+    def _shim_objc_to_legacy_objc_type_mapper(self, data_type, mapped_object_name):
+        if data_type.name == 'Void':
+            return 'nil'
+        elif is_list_type(data_type):
+            if is_user_defined_type(data_type.data_type):
+                list_data_type = fmt_objc_type(data_type.data_type)
+                return '{}?.map {{ map{}ToDBOptional(object: $0) }}'.format(mapped_object_name,
+                                                                            list_data_type)
+            else:
+                return '{}'.format(mapped_object_name)
+        else:
+            return 'map{}ToDBOptional(object: {})'.format(fmt_objc_type(data_type),
+                                                        mapped_object_name)
+
     def _background_compatible_routes_for_objc_requests(self, api):
         namespaces = api.namespaces.values()
         objc_class_to_route = {}

stone/backends/swift_helpers.py

@@ -138,7 +138,6 @@ def fmt_func(name, version):
     name = _format_camelcase(name)
     return name
 
-
 def fmt_type(data_type):
     data_type, nullable = unwrap_nullable(data_type)
 
@@ -175,6 +174,11 @@ def fmt_objc_type(data_type, allow_nullable=True):
 def fmt_var(name):
     return _format_camelcase(name)
 
+# Type check component when mapping an objc union to a legacy objc union
+# e.g.: `asPricePlanTypePremium`
+def fmt_shim_union_psuedo_cast(name):
+    arg = _format_camelcase(name, lower_first=False)
+    return 'as{}'.format(arg)
 
 def fmt_default_value(field):
     if is_tag_ref(field.default):
@@ -267,6 +271,17 @@ def field_is_user_defined_list(field):
 # List[typing.Tuple[let_name: str, swift_type: str, objc_type: str]]
 def objc_datatype_value_type_tuples(data_type):
     ret = []
+    for d_type in datatype_subtype_value_types(data_type):
+        case_let_name = fmt_var(d_type.name)
+        swift_type = fmt_type(d_type)
+        objc_type = fmt_objc_type(d_type)
+        ret.append((case_let_name, swift_type, objc_type))
+
+    return ret
+
+# List[typing.Tuple[let_name: str, type: DataType]]
+def datatype_subtype_value_types(data_type):
+    ret = []
 
     # if list type get the data type of the item
     if is_list_type(data_type):
@@ -282,15 +297,8 @@ def objc_datatype_value_type_tuples(data_type):
 
         for subtype in all_subtypes:
             # subtype[0] is the tag name and subtype[1] is the subtype struct itself
-            struct = subtype[1]
-            case_let_name = fmt_var(struct.name)
-            swift_type = fmt_type(struct)
-            objc_type = fmt_objc_type(struct)
-            ret.append((case_let_name, swift_type, objc_type))
+            ret.append((subtype[1]))
     return ret
 
-def field_datatype_has_subtypes(field) -> bool:
-    return datatype_has_subtypes(field.data_type)
-
 def datatype_has_subtypes(data_type) -> bool:
     return len(objc_datatype_value_type_tuples(data_type)) > 0

stone/backends/swift_rsrc/ObjCRoutes.jinja

@@ -104,20 +104,41 @@ public class {{ fmt_route_objc_class(namespace, route, args_data) }}: NSObject,
         self.response(queue: nil, completionHandler: completionHandler)
     }
 
+    {% if route.attrs.get('style') == 'rpc' and ('user' in route.attrs.get('auth') or 'noauth' in route.attrs.get('auth')) and not route.deprecated %}
     @objc
     @discardableResult public func response(
         queue: DispatchQueue?,
         completionHandler: @escaping ({{ result_type }}) -> Void
     ) -> Self {
+        self.response(queue: nil, analyticsBlock: nil, completionHandler: completionHandler)
+    }
+    {% endif %}
+
+    @objc
+    @discardableResult public func response(
+        queue: DispatchQueue? = nil,
+        {% if route.attrs.get('style') == 'rpc' and ('user' in route.attrs.get('auth') or 'noauth' in route.attrs.get('auth')) and not route.deprecated %}
+        analyticsBlock: AnalyticsBlock? = nil,
+        {% endif %}
+        completionHandler: @escaping ({{ result_type }}) -> Void
+    ) -> Self {
+        {% if route.attrs.get('style') == 'rpc' and ('user' in route.attrs.get('auth') or 'noauth' in route.attrs.get('auth')) and not route.deprecated %}
+        swift.response(queue: queue, analyticsBlock: analyticsBlock) { result, error in
+        {% else %}
         swift.response(queue: queue) { result, error in
+        {% endif %}
             {% if route.error_data_type.name != 'Void' %}
             {% set error_type = 'DBX' + fmt_class(route.error_data_type.namespace.name) + fmt_class(route.error_data_type.name) %}
             {% set error_call = 'routeError, callError' %}
             var routeError: {{ error_type }}?
             var callError: DBXCallError?
             switch error {
             case .routeError(let box, _, _, _):
+                {% if is_union_type(route.error_data_type) %}
+                routeError = {{ error_type }}.factory(swift: box.unboxed)
+                {% else %}
                 routeError = {{ error_type }}(swift: box.unboxed)
+                {% endif %}
                 callError = nil
             default:
                 routeError = nil

stone/backends/swift_rsrc/ObjcTypes.jinja

@@ -22,23 +22,7 @@ public class DBX{{ namespace_class_name }}{{ data_type_class_name }}: {{ 'NSObje
     {% for field in data_type.fields %}
     {{ struct_field_doc(field, '    ') }}
     @objc
-    {% if field_datatype_has_subtypes(field) %}
-    public var {{ fmt_var(field.name) }}: {{ fmt_objc_type(field.data_type) }} {
-        {% if (field_is_user_defined(field)) or (field_is_user_defined_optional(field)) %}
-        {% if field_is_user_defined_optional(field) %}
-        return {{ swift_var_name }}.{{ fmt_var(field.name) }}.flatMap { {{ fmt_objc_type(field.data_type, False) }}.wrapPreservingSubtypes(swift: $0) }
-        {% else %}
-        return {{ fmt_objc_type(field.data_type) }}.wrapPreservingSubtypes(swift: {{ swift_var_name }}.{{ fmt_var(field.name) }})
-        {% endif %}
-        {% elif (field_is_user_defined_map(field)) or (field_is_user_defined_list(field)) %}
-        {{ swift_var_name }}.{{ fmt_var(field.name) }}.{{ 'mapValues' if field_is_user_defined_map(field) else 'map' }} {
-            return {{ fmt_objc_type(field.data_type.data_type) }}.wrapPreservingSubtypes(swift: $0)
-        }
-        {% endif %}
-    }
-    {% else %}
     public var {{ fmt_var(field.name) }}: {{ fmt_objc_type(field.data_type) }} { {{ objc_return_field_value_oneliner(data_type, field) }} }
-    {% endif %}
     {% endfor %}
     {% if data_type.fields %}
 
@@ -52,11 +36,24 @@ public class DBX{{ namespace_class_name }}{{ data_type_class_name }}: {{ 'NSObje
         self.{{ swift_var_name }} = {{ swift_type }}({{ objc_init_args_to_swift(data_type) }})
         {% endif %}
     }
+    {% elif data_type.parent_type.fields %}
+
+    @objc
+    public override init({{ func_args(objc_init_args(data_type.parent_type)) }}) {
+        let swift = {{ swift_type }}({{ objc_init_args_to_swift(data_type.parent_type) }})
+        self.{{ swift_var_name }} = swift
+        super.init(swift: swift)
+    }
+    {% elif not data_type.parent_type %}
+    public override init() {
+        self.{{ swift_var_name }} = {{ swift_type }}()
+        super.init()
+    }
     {% endif %}
 
-    let {{ swift_var_name }}: {{ swift_type }}
+    public let {{ swift_var_name }}: {{ swift_type }}
 
-    public init(swift: {{ swift_type }}) {
+    {{ "fileprivate" if (objc_datatype_value_type_tuples(data_type)|length > 0) else "public" }} init(swift: {{ swift_type }}) {
         self.{{ swift_var_name }} = swift
         {% if data_type.parent_type %}
         super.init(swift: swift)
@@ -74,6 +71,7 @@ public class DBX{{ namespace_class_name }}{{ data_type_class_name }}: {{ 'NSObje
             return DBX{{ namespace_class_name }}{{ data_type_class_name }}(swift: swift)
         }
     }
+    {% else %}
     {% endif %}
 
     @objc
@@ -85,9 +83,9 @@ public class DBX{{ namespace_class_name }}{{ data_type_class_name }}: {{ 'NSObje
 {% set swift_enum = namespace_class_name + '.' + fmt_class(data_type.name) %}
 @objc
 public class {{ union_class_name }}: NSObject {
-    let swift: {{ swift_enum }}
+    public let swift: {{ swift_enum }}
 
-    public init(swift: {{ swift_enum }}) {
+    fileprivate init(swift: {{ swift_enum }}) {
         self.swift = swift
     }
 

stone/backends/swift_rsrc/SwiftObjcArgTypeMappings.jinja

@@ -0,0 +1,51 @@
+///
+/// Copyright (c) 2024 Dropbox, Inc. All rights reserved.
+///
+/// Auto-generated by Stone, do not modify.
+///
+
+import Foundation
+import stone_sdk_objc
+import stone_sdk_swift
+import stone_sdk_swift_objc
+
+{% for data_type in namespace.linearize_data_types() %}
+{% set dbx_data_type_class_name = fmt_objc_type(data_type) %}
+{% set db_data_type_class_name = fmt_class_prefix(data_type) %}
+func map{{ db_data_type_class_name }}ToDBXOptional(object: {{ db_data_type_class_name}}?) -> {{ dbx_data_type_class_name }}? {
+    guard let object = object else { return nil }
+    return map{{ db_data_type_class_name }}ToDBX(object: object)
+}
+
+func map{{ db_data_type_class_name }}ToDBX(object: {{ db_data_type_class_name}}) -> {{ dbx_data_type_class_name }} {
+    {% if is_struct_type(data_type) %}
+    {% if datatype_subtype_value_types(data_type)|length > 0 %}
+    switch object {
+    {% for type in datatype_subtype_value_types(data_type) %}
+    case let object as {{ fmt_class_prefix(type) }}:
+        return {{ fmt_objc_type(type) }}({{ shim_legacy_objc_init_args_to_objc(type, 'object') }})
+    {% endfor %}
+    default:
+        return {{ dbx_data_type_class_name }}({{ shim_legacy_objc_init_args_to_objc(data_type, 'object') }})
+    }
+    {% else %}
+    return {{ dbx_data_type_class_name }}({{ shim_legacy_objc_init_args_to_objc(data_type, 'object') }})
+    {% endif %}
+    {% elif is_union_type(data_type) %}
+    {% for field in data_type.all_fields %}
+    {% set case_class = dbx_data_type_class_name + fmt_class(field.name) %}
+    {% set case_var_name = fmt_var(field.name) %}
+    if object.{{ fmt_legacy_objc_union_case_check(field.name, data_type) }}() {
+        {% if not is_void_type(field.data_type) %}
+        let {{ case_var_name }} = {{ shim_legacy_objc_union_associated_type(field, data_type) }}
+        return {{ dbx_data_type_class_name }}.factory(swift: {{ shim_legacy_objc_union_associated_type_init(field) }})
+        {% else %}
+        return {{ case_class }}()
+        {% endif %}
+    }
+    {% endfor %}
+    fatalError("codegen error")
+    {% endif %}
+}
+
+{% endfor %}