WIP query

README.md

@@ -69,12 +69,12 @@ As specified in step 3 of the _Getting started_ section, Dart's _build\_runner_
 import "../lib/objectbox.dart";
 part "basics_test.g.dart";
 
-@Entity(id: 1, uid: 1)
+@Entity()
 class Note {
-    @Id(id: 1, uid: 1001)       // automatically always 'int' in Dart code and 'Long' in ObjectBox
+    @Id()       // automatically always 'int' in Dart code and 'Long' in ObjectBox
     int id;
 
-    @Property(id: 2, uid: 1002)
+    @Property(uid: 1002)
     String text;
 
     Note();             // empty default constructor needed
@@ -98,6 +98,44 @@ print("refetched note: ${box.get(note.id)}");
 store.close();
 ```
 
+Query and QueryBuilder
+----------------------
+
+Basic querying can be done with e.g.:
+
+```dart
+// var store ...
+// var box ...
+
+box.putMany([Note(), Note(), Note()]);
+box.put(Note.construct("Hello world!"));
+
+final text = Note_.text;
+final queryNullText = box.query(text.isNull()).build();
+
+assert (queryNullText.count() == 3);
+
+queryNullText.close(); // We have to manually close queries and query builders.
+```
+
+More complex queries can be constructed using `and/or` operators.
+Also there is basic operator overloading support for `equal`, `greater`, `less`, `and` and `or`,
+respectively `==`, `>`, `<`, `&`, `|`.
+
+```dart
+final anyGroup = <QueryCondition>[text.equals("meh"), text.equals("bleh"), text.contains("Hello")];
+final queryAny = box.queryAny(anyGroup).build();
+
+// equivalent to
+
+box.query(text.equal("meh").or(text.equal("bleh")).or(text.contains("Hello"))).build();
+
+// equivalent to
+
+final overloaded = ((text == "meh") | (text == "bleh")) | text.contains("Hello");
+box.query(overloaded as QueryCondition).build(); // the cast is necessary due to the type analyzer
+```
+
 Basic technical approach
 ------------------------
 ObjectBox offers a [C API](https://github.com/objectbox/objectbox-c) which can be called by [Dart FFI](https://dart.dev/server/c-interop).

bin/objectbox_model_generator/lib/src/code_chunks.dart

@@ -1,4 +1,7 @@
 import "package:objectbox/src/modelinfo/index.dart";
+import "package:analyzer/dart/element/element.dart";
+import "package:objectbox/src/bindings/constants.dart" show OBXPropertyType;
+import "package:source_gen/source_gen.dart" show InvalidGenerationSourceError;
 
 class CodeChunks {
   static String modelInfoLoader(String allModelsJsonFilename) => """
@@ -43,4 +46,59 @@ class CodeChunks {
         const ${name}_OBXDefs = EntityDefinition<${name}>(_${name}_OBXModelGetter, _${name}_OBXReader, _${name}_OBXBuilder);
       """;
   }
+
+  static String _queryConditionBuilder(ModelEntity readEntity) {
+    final ret = <String>[];
+    for (var f in readEntity.properties) {
+
+      final name = f.name;
+
+      // see OBXPropertyType
+      String fieldType;
+      switch(f.type) {
+        case OBXPropertyType.Bool:
+          fieldType = "Boolean";
+          break;
+        case OBXPropertyType.String:
+          fieldType = "String";
+          break;
+        float:
+        case OBXPropertyType.Double:
+          fieldType = "Double";
+          break;
+        case OBXPropertyType.Float:
+          continue float;
+        integer:
+        case OBXPropertyType.Int:
+          fieldType = "Integer";
+          break;
+        case OBXPropertyType.Byte:
+          continue integer;
+        case OBXPropertyType.Short:
+          continue integer;
+        case OBXPropertyType.Char:
+          continue integer;
+        case OBXPropertyType.Long:
+          continue integer;
+        default:
+          throw InvalidGenerationSourceError("Unsupported property type (${f.type}): ${readEntity.name}.${name}");
+      }
+
+      ret.add("""
+        static final ${name}PropertyType = ${f.type};
+        static final ${name}PropertyId = ${f.id.id};
+        static final ${name} = Query${fieldType}Property(entityId, ${name}PropertyId, ${name}PropertyType);
+        """);
+    }
+    return ret.join();
+  }
+
+  static String queryConditionClasses(ModelEntity readEntity) {
+    // TODO add entity.id check to throw an error Box if the wrong entity.property is used
+    return """
+    class ${readEntity.name}_ {
+      static final entityId = ${readEntity.id.id};
+      ${_queryConditionBuilder(readEntity)}
+    }""";
+  }
 }

bin/objectbox_model_generator/lib/src/generator.dart

@@ -78,7 +78,8 @@ class EntityGenerator extends GeneratorForAnnotation<obx.Entity> {
             flags |= OBXPropertyFlag.ID;
             hasIdProperty = true;
           } else if (annotType == "Property") {
-            // nothing special
+            fieldType = annotVal.getField("type")?.toIntValue();
+            flags |= annotVal.getField("flag")?.toIntValue();
           } else {
             // skip unknown annotations
             print(
@@ -93,6 +94,10 @@ class EntityGenerator extends GeneratorForAnnotation<obx.Entity> {
             fieldType = OBXPropertyType.Int;
           else if (fieldTypeStr == "String")
             fieldType = OBXPropertyType.String;
+          else if (fieldTypeStr == "bool")
+            fieldType = OBXPropertyType.Bool;
+          else if (fieldTypeStr == "double")
+            fieldType = OBXPropertyType.Double;
           else {
             print(
                 "warning: skipping field '${f.name}' in entity '${element.name}', as it has the unsupported type '$fieldTypeStr'");
@@ -119,6 +124,9 @@ class EntityGenerator extends GeneratorForAnnotation<obx.Entity> {
       // main code for instance builders and readers
       ret += CodeChunks.instanceBuildersReaders(readEntity);
 
+      // for building queries
+      ret += CodeChunks.queryConditionClasses(readEntity);
+
       return ret;
     } catch (e, s) {
       print(s);

lib/objectbox.dart

@@ -9,3 +9,4 @@ export "src/model.dart";
 export "src/store.dart";
 export "src/box.dart";
 export "src/modelinfo/index.dart";
+export "src/query/index.dart";

lib/src/annotations.dart

@@ -3,9 +3,19 @@ class Entity {
   const Entity({this.uid = null});
 }
 
+/**
+ * A dart int value can map to different OBXPropertyTypes,
+ * e.g. Short (Int16), Int (Int32), Long (Int64), all signed values.
+ * Also a dart double can also map to e.g. Float and Double
+ *
+ * Property allows the mapping to be specific. The defaults are
+ * e.g. Int -> Int64, double -> Float64, bool -> Bool.
+ *
+ * Use OBXPropertyType and OBXPropertyFlag values, resp. for type and flag.
+ */
 class Property {
-  final int uid;
-  const Property({this.uid = null});
+  final int uid, type, flag;
+  const Property({this.type = null, this.flag = null, this.uid = null});
 }
 
 class Id {

lib/src/bindings/bindings.dart

@@ -10,7 +10,11 @@ class _ObjectBoxBindings {
   // common functions
   void Function(Pointer<Int32> major, Pointer<Int32> minor, Pointer<Int32> patch) obx_version;
   Pointer<Uint8> Function() obx_version_string;
-  void Function(Pointer<Uint64> array) obx_bytes_array_free;
+  void Function(Pointer<Uint64> structPtr)
+    obx_bytes_array_free, obx_id_array_free, obx_string_array_free,
+    obx_int64_array_free, obx_int32_array_free,
+    obx_int16_array_free, obx_int8_array_free,
+    obx_double_array_free, obx_float_array_free;
 
   // error info
   int Function() obx_last_error_code;
@@ -59,6 +63,57 @@ class _ObjectBoxBindings {
   int Function(Pointer<Void> box, Pointer<Uint64> objects, Pointer<Uint64> ids, int mode) obx_box_put_many;
   int Function(Pointer<Void> box, int id) obx_box_remove;
 
+  // query builder
+  obx_query_builder_dart_t obx_qb_create;
+  obx_qb_close_dart_t obx_qb_close;
+  obx_qb_close_dart_t obx_qb_error_code;
+  obx_qb_error_message_t obx_qb_error_message;
+
+  obx_qb_cond_operator_0_dart_t obx_qb_null, obx_qb_not_null;
+
+  obx_qb_cond_operator_1_dart_t<int>
+    obx_qb_int_equal, obx_qb_int_not_equal,
+    obx_qb_int_greater, obx_qb_int_less;
+
+  obx_qb_cond_operator_2_dart_t<int> obx_qb_int_between;
+
+  obx_qb_cond_operator_in_dart_t<Int64> obx_qb_int64_in, obx_qb_int64_not_in;
+  obx_qb_cond_operator_in_dart_t<Int32> obx_qb_int32_in, obx_qb_int32_not_in;
+
+  obx_qb_cond_string_op_1_dart_t
+    obx_qb_string_equal,
+    obx_qb_string_not_equal,
+    obx_qb_string_contains,
+    obx_qb_string_starts_with,
+    obx_qb_string_ends_with;
+
+  obx_qb_cond_operator_1_dart_t<double> obx_qb_double_greater, obx_qb_double_less;
+  obx_qb_cond_operator_2_dart_t<double> obx_qb_double_between;
+
+  obx_qb_string_lt_gt_op_dart_t obx_qb_string_greater, obx_qb_string_less;
+  obx_qb_string_in_dart_t obx_qb_string_in;
+
+  obx_qb_bytes_eq_dart_t obx_qb_bytes_equal;
+  obx_qb_bytes_lt_gt_dart_t obx_qb_bytes_greater, obx_qb_bytes_less;
+
+  obx_qb_join_op_dart_t obx_qb_all, obx_qb_any;
+
+  obx_qb_param_alias_dart_t obx_qb_param_alias;
+
+  obx_qb_order_dart_t obx_qb_order;
+
+  // query
+  obx_query_t obx_query_create;
+  obx_query_close_dart_t obx_query_close;
+  obx_query_find_t<int> obx_query_find;
+  obx_query_find_t<int> obx_query_find_ids;
+
+  obx_query_count_dart_t obx_query_count, obx_query_remove;
+
+  obx_query_describe_t obx_query_describe, obx_query_describe_params;
+
+  obx_query_visit_dart_t obx_query_visit;
+
   // TODO return .asFunction() -> requires properly determined static return type
   Pointer<NativeFunction<T>> _fn<T extends Function>(String name) {
     return objectbox.lookup<NativeFunction<T>>(name);
@@ -79,7 +134,15 @@ class _ObjectBoxBindings {
     // common functions
     obx_version = _fn<obx_version_native_t>("obx_version").asFunction();
     obx_version_string = _fn<obx_version_string_native_t>("obx_version_string").asFunction();
-    obx_bytes_array_free = _fn<obx_bytes_array_free_native_t>("obx_bytes_array_free").asFunction();
+    obx_bytes_array_free = _fn<obx_free_struct_native_t>("obx_bytes_array_free").asFunction();
+    obx_id_array_free = _fn<obx_free_struct_native_t>("obx_id_array_free").asFunction();
+    obx_string_array_free = _fn<obx_free_struct_native_t>("obx_string_array_free").asFunction();
+    obx_int64_array_free = _fn<obx_free_struct_native_t>("obx_int64_array_free").asFunction();
+    obx_int32_array_free = _fn<obx_free_struct_native_t>("obx_int32_array_free").asFunction();
+    obx_int16_array_free = _fn<obx_free_struct_native_t>("obx_int16_array_free").asFunction();
+    obx_int8_array_free = _fn<obx_free_struct_native_t>("obx_int8_array_free").asFunction();
+    obx_double_array_free = _fn<obx_free_struct_native_t>("obx_double_array_free").asFunction();
+    obx_float_array_free = _fn<obx_free_struct_native_t>("obx_float_array_free").asFunction();
 
     // error info
     obx_last_error_code = _fn<obx_last_error_code_native_t>("obx_last_error_code").asFunction();
@@ -126,6 +189,70 @@ class _ObjectBoxBindings {
     obx_box_put = _fn<obx_box_put_native_t>("obx_box_put").asFunction();
     obx_box_put_many = _fn<obx_box_put_many_native_t>("obx_box_put_many").asFunction();
     obx_box_remove = _fn<obx_box_remove_native_t>("obx_box_remove").asFunction();
+
+    // query builder
+    obx_qb_create = _fn<obx_query_builder_native_t>("obx_query_builder").asFunction();
+    obx_qb_close = _fn<obx_qb_close_native_t>("obx_qb_close").asFunction();
+    obx_qb_error_code = _fn<obx_qb_close_native_t>("obx_qb_error_code").asFunction();
+    obx_qb_error_message = _fn<obx_qb_error_message_t>("obx_qb_error_message").asFunction();
+
+    obx_qb_null = _fn<obx_qb_cond_operator_0_native_t>("obx_qb_null").asFunction();
+    obx_qb_not_null = _fn<obx_qb_cond_operator_0_native_t>("obx_qb_not_null").asFunction();
+
+    obx_qb_int_equal = _fn<obx_qb_cond_operator_1_native_t<Int64>>("obx_qb_int_equal").asFunction();
+    obx_qb_int_not_equal = _fn<obx_qb_cond_operator_1_native_t<Int64>>("obx_qb_int_not_equal").asFunction();
+    obx_qb_int_greater = _fn<obx_qb_cond_operator_1_native_t<Int64>>("obx_qb_int_greater").asFunction();
+    obx_qb_int_less = _fn<obx_qb_cond_operator_1_native_t<Int64>>("obx_qb_int_less").asFunction();
+
+    obx_qb_int_between = _fn<obx_qb_cond_operator_2_native_t<Int64>>("obx_qb_int_between").asFunction();
+
+    obx_qb_int64_in = _fn<obx_qb_cond_operator_in_native_t<Int64>>("obx_qb_int64_in").asFunction();
+    obx_qb_int64_not_in = _fn<obx_qb_cond_operator_in_native_t<Int64>>("obx_qb_int64_not_in").asFunction();
+
+    obx_qb_int32_in = _fn<obx_qb_cond_operator_in_native_t<Int32>>("obx_qb_int32_in").asFunction();
+    obx_qb_int32_not_in = _fn<obx_qb_cond_operator_in_native_t<Int32>>("obx_qb_int32_not_in").asFunction();
+
+    obx_qb_string_equal = _fn<obx_qb_cond_string_op_1_native_t>("obx_qb_string_equal").asFunction();
+    obx_qb_string_not_equal = _fn<obx_qb_cond_string_op_1_native_t>("obx_qb_string_not_equal").asFunction();
+    obx_qb_string_contains = _fn<obx_qb_cond_string_op_1_native_t>("obx_qb_string_contains").asFunction();
+
+    obx_qb_string_starts_with = _fn<obx_qb_cond_string_op_1_native_t>("obx_qb_string_starts_with").asFunction();
+    obx_qb_string_ends_with = _fn<obx_qb_cond_string_op_1_native_t>("obx_qb_string_ends_with").asFunction();
+
+    obx_qb_string_greater = _fn<obx_qb_string_lt_gt_op_native_t>("obx_qb_string_greater").asFunction();
+    obx_qb_string_less    = _fn<obx_qb_string_lt_gt_op_native_t>("obx_qb_string_less").asFunction();
+
+    obx_qb_string_in = _fn<obx_qb_string_in_native_t>("obx_qb_string_in").asFunction();
+
+    obx_qb_double_greater = _fn<obx_qb_cond_operator_1_native_t<Double>>("obx_qb_double_greater").asFunction();
+    obx_qb_double_less = _fn<obx_qb_cond_operator_1_native_t<Double>>("obx_qb_double_less").asFunction();
+
+    obx_qb_double_between = _fn<obx_qb_cond_operator_2_native_t<Double>>("obx_qb_double_between").asFunction();
+
+    obx_qb_bytes_equal = _fn<obx_qb_bytes_eq_native_t>("obx_qb_bytes_equal").asFunction();
+    obx_qb_bytes_greater = _fn<obx_qb_bytes_lt_gt_native_t>("obx_qb_bytes_greater").asFunction();
+    obx_qb_bytes_less = _fn<obx_qb_bytes_lt_gt_native_t>("obx_qb_bytes_less").asFunction();
+
+    obx_qb_all = _fn<obx_qb_join_op_native_t>("obx_qb_all").asFunction();
+    obx_qb_any = _fn<obx_qb_join_op_native_t>("obx_qb_any").asFunction();
+
+    obx_qb_param_alias = _fn<obx_qb_param_alias_native_t>("obx_qb_param_alias").asFunction();
+
+    obx_qb_order = _fn<obx_qb_order_native_t>("obx_qb_order").asFunction();
+
+    // query
+    obx_query_create = _fn<obx_query_t>("obx_query").asFunction();
+    obx_query_close = _fn<obx_query_close_native_t>("obx_query_close").asFunction();
+
+    obx_query_find_ids = _fn<obx_query_find_t<Uint64>>("obx_query_find_ids").asFunction();
+    obx_query_find     = _fn<obx_query_find_t<Uint64>>("obx_query_find").asFunction();
+
+    obx_query_count = _fn<obx_query_count_native_t>("obx_query_count").asFunction();
+    obx_query_remove = _fn<obx_query_count_native_t>("obx_query_remove").asFunction();
+    obx_query_describe = _fn<obx_query_describe_t>("obx_query_describe").asFunction();
+    obx_query_describe_params = _fn<obx_query_describe_t>("obx_query_describe_params").asFunction();
+
+    obx_query_visit = _fn<obx_query_visit_native_t>("obx_query_visit").asFunction();
   }
 }
 

lib/src/bindings/constants.dart

@@ -83,3 +83,25 @@ class OBXError {
   /// A requested schema object (e.g. entity or property) was not found in the schema
   static const int OBX_ERROR_SCHEMA_OBJECT_NOT_FOUND = 10503;
 }
+
+// query builder
+
+class OBXOrderFlag {
+  /// Reverts the order from ascending (default) to descending.
+  static final DESCENDING = 1;
+
+  /// Makes upper case letters (e.g. "Z") be sorted before lower case letters (e.g. "a").
+  /// If not specified, the default is case insensitive for ASCII characters.
+  static final CASE_SENSITIVE = 2;
+
+  /// For scalars only: changes the comparison to unsigned (default is signed).
+  static final UNSIGNED = 4;
+
+  /// null values will be put last.
+  /// If not specified, by default null values will be put first.
+  static final NULLS_LAST = 8;
+
+  /// null values should be treated equal to zero (scalars only).
+  static final NULLS_ZERO = 16;
+}
+

lib/src/bindings/flatbuffers.dart

@@ -73,6 +73,12 @@ class OBXFlatbuffersManager<T> {
         case OBXPropertyType.String:
           builder.addOffset(field, offsets[p.name]);
           break;
+        case OBXPropertyType.Float:
+          builder.addFloat32(field, value);
+          break;
+        case OBXPropertyType.Double:
+          builder.addFloat64(field, value);
+          break;
         default:
           throw Exception("unsupported type: ${p.type}"); // TODO: support more types
       }
@@ -111,6 +117,12 @@ class OBXFlatbuffersManager<T> {
         case OBXPropertyType.String:
           propReader = fb.StringReader();
           break;
+        case OBXPropertyType.Float:
+          propReader = fb.Float32Reader();
+          break;
+        case OBXPropertyType.Double:
+          propReader = fb.Float64Reader();
+          break;
         default:
           throw Exception("unsupported type: ${p.type}"); // TODO: support more types
       }