Implement property conversion

Author: jakhog

Source/projections/Builders/Copies/MongoDBConversionDecoratedProperty.ts

@@ -0,0 +1,23 @@
+// Copyright (c) Dolittle. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+import { Constructor } from '@dolittle/types';
+import { ProjectionField } from '../../Copies/ProjectionField';
+import { Conversion } from '../../Copies/MongoDB/Conversion';
+
+/**
+ * Represents a projection property decorated with a 'covertToMongoDB' decorator.
+ */
+export class MongoDBConversionDecoratedProperty {
+    /**
+     * Initialises a new instance of the {@link MongoDBConversionDecoratedProperty} class.
+     * @param {ProjectionField} field - The projection field to be converted.
+     * @param {Conversion} conversion - The conversion to apply.
+     * @param {Constructor<any>} type - The decorated type.
+     */
+    constructor(
+        readonly field: ProjectionField,
+        readonly conversion: Conversion,
+        readonly type: Constructor<any>
+    ) { }
+}

Source/projections/Builders/Copies/_exports.ts

@@ -1,8 +1,10 @@
 // Copyright (c) Dolittle. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+export { convertToMongoDB, getConvertToMongoDBDecoratedProperties } from './convertToMongoDBDecorator';
 export { CopyProjectionToMongoDBDecoratedType } from './CopyProjectionToMongoDBDecoratedType';
 export { copyProjectionToMongoDB, isDecoratedCopyProjectionToMongoDB, getDecoratedCopyProjectionToMongoDB } from './copyProjectionToMongoDBDecorator';
 export { CopyToMongoDBBuilder } from './CopyToMongoDBBuilder';
 export { CopyToMongoDBCallback } from './CopyToMongoDBCallback';
 export { ICopyToMongoDBBuilder } from './ICopyToMongoDBBuilder';
+export { MongoDBConversionDecoratedProperty } from './MongoDBConversionDecoratedProperty';

Source/projections/Builders/Copies/convertToMongoDBDecorator.ts

@@ -0,0 +1,38 @@
+// Copyright (c) Dolittle. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+import { Decorators } from '@dolittle/sdk.common';
+import { Constructor } from '@dolittle/types';
+
+import { ProjectionField } from '../../Copies/ProjectionField';
+import { Conversion } from '../../Copies/MongoDB/Conversion';
+import { MongoDBConversionDecoratedProperty } from './MongoDBConversionDecoratedProperty';
+
+const [decorator, getMetadata] = Decorators.createMetadataDecorator<MongoDBConversionDecoratedProperty[]>('projection-copy-to-mongodb-conversions', 'convertToMongoDB', Decorators.DecoratorTarget.Property);
+
+/**
+ * Decorator for specifying conversions to be applied when producing read model copies to MongoDB.
+ * @param {Conversion} conversion - The conversion to apply for the decorated property.
+ * @returns {Decorators.Decorator} The decorator.
+ */
+export function convertToMongoDB(conversion: Conversion): Decorators.Decorator {
+    return decorator((target, type, propertyKey, _ , mongoDBConversionDecoratedProperties) => {
+        const properties = mongoDBConversionDecoratedProperties || [];
+
+        properties.push(new MongoDBConversionDecoratedProperty(
+            ProjectionField.from(propertyKey as string),
+            conversion,
+            type));
+
+        return properties;
+    });
+}
+
+/**
+ * Gets the MongoDB conversion decorated projection properties of the specified class.
+ * @param {Constructor<any>} type - The class to get the MongoDB conversion decorated projection properties for.
+ * @returns {MongoDBConversionDecoratedProperty[]} The MongoDB conversion decorated projection properties.
+ */
+export function getConvertToMongoDBDecoratedProperties(type: Constructor<any>): MongoDBConversionDecoratedProperty[] {
+    return getMetadata(type) || [];
+}

Source/projections/Builders/Copies/copyProjectionToMongoDBDecorator.ts

@@ -7,7 +7,7 @@ import { CollectionName, CollectionNameLike } from '../../Copies/MongoDB/Collect
 
 import { CopyProjectionToMongoDBDecoratedType } from './CopyProjectionToMongoDBDecoratedType';
 
-const [decorator, getMetadata] = Decorators.createMetadataDecorator<CopyProjectionToMongoDBDecoratedType>('copy-projection-to-mongodb', 'copyProjectionToMongoDB', Decorators.DecoratorTarget.Class);
+const [decorator, getMetadata] = Decorators.createMetadataDecorator<CopyProjectionToMongoDBDecoratedType>('projection-copy-to-mongodb', 'copyProjectionToMongoDB', Decorators.DecoratorTarget.Class);
 
 /**
  * Decorator to mark a Projection class to copy the read models to a MongoDB collection.

Source/projections/Builders/ProjectionClassBuilder.ts

@@ -4,7 +4,7 @@
 import { Guid, IEquatable } from '@dolittle/rudiments';
 import { Constructor } from '@dolittle/types';
 
-import { Generation } from '@dolittle/sdk.artifacts';
+import { ComplexValueMap, Generation } from '@dolittle/sdk.artifacts';
 import { IClientBuildResults } from '@dolittle/sdk.common';
 import { EventType, EventTypeId, EventTypeIdLike, EventTypeMap,  IEventTypes } from '@dolittle/sdk.events';
 
@@ -13,12 +13,15 @@ import { IProjection } from '../IProjection';
 import { KeySelector } from '../KeySelector';
 import { Projection } from '../Projection';
 import { ProjectionCallback } from '../ProjectionCallback';
-import { OnDecoratedProjectionMethod } from './OnDecoratedProjectionMethod';
-import { getOnDecoratedMethods } from './onDecorator';
-import { ProjectionDecoratedType } from './ProjectionDecoratedType';
 import { ProjectionCopies } from '../Copies/ProjectionCopies';
+import { ProjectionField } from '../Copies/ProjectionField';
+import { Conversion } from '../Copies/MongoDB/Conversion';
 import { MongoDBCopies } from '../Copies/MongoDB/MongoDBCopies';
+import { getConvertToMongoDBDecoratedProperties } from './Copies/convertToMongoDBDecorator';
 import { getDecoratedCopyProjectionToMongoDB, isDecoratedCopyProjectionToMongoDB } from './Copies/copyProjectionToMongoDBDecorator';
+import { OnDecoratedProjectionMethod } from './OnDecoratedProjectionMethod';
+import { getOnDecoratedMethods } from './onDecorator';
+import { ProjectionDecoratedType } from './ProjectionDecoratedType';
 
 /**
  * Represents a builder for building a projection from a class.
@@ -132,9 +135,14 @@ export class ProjectionClassBuilder<T> implements IEquatable {
         }
 
         const decoratedType = getDecoratedCopyProjectionToMongoDB(this.type.type);
+        const collection = decoratedType.collection;
 
-        // TODO: Conversions
+        const decoratedProperties = getConvertToMongoDBDecoratedProperties(this.type.type);
+        const conversions: Map<ProjectionField, Conversion> = new ComplexValueMap(ProjectionField, field => [field.value], 1);
+        for (const decoratedProperty of decoratedProperties) {
+            conversions.set(decoratedProperty.field, decoratedProperty.conversion);
+        }
 
-        return new MongoDBCopies(true, decoratedType.collection, new Map());
+        return new MongoDBCopies(true, collection, conversions);
     }
 }

Source/projections/index.ts

@@ -32,13 +32,16 @@ export {
 } from './Builders/_exports';
 
 export {
+    convertToMongoDB,
+    getConvertToMongoDBDecoratedProperties,
+    CopyProjectionToMongoDBDecoratedType,
     copyProjectionToMongoDB,
     isDecoratedCopyProjectionToMongoDB,
     getDecoratedCopyProjectionToMongoDB,
-    CopyProjectionToMongoDBDecoratedType,
     CopyToMongoDBBuilder,
     CopyToMongoDBCallback,
     ICopyToMongoDBBuilder,
+    MongoDBConversionDecoratedProperty,
 } from './Builders/Copies/_exports';
 
 export {