Adds a registry based mechanism for registering Custom GraphQL scalars (

#1131) * Added support for OffsetDateTimeScalar scalar and refactored GraphQLConversionUtils implementation to support runtime detection and registration of GraphQl Scalars * Added ElideCoercing Interface which has method to allow implementations to return Serde for a given Scalar Added usesSerdeOfType field in ElideScalarType annotation to give user flexibility to specify Type for which Serde is written * Adding test cases for OffsetDateTime scalar and GraphQLConversionUtils * Applied style check suggestion * Applied Codacy suggestion * Update OffsetDateTimeSerde.java Fixing checkstyles. * Elide Annotaion now supports subtypes Elide Annotaion now registers Serde instead of ElideCoercing Auto-scan happens on Elide initialization * Applied PR Review Suggestions 1. Fixed typos 2. Removed unused method from ClassScanner 3. Added suggested refactored Serde scanning code 4. CoerceUtil now returns Immutable Serde map * Fixing checkstyle (extra space) Co-authored-by: Aaron Klish <[email protected]>
yahoo · Jan 16, 2020 · cd2a159 · cd2a159
1 parent 5c43ee8
commit cd2a159
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Showing 11 changed files with 340 additions and 3 deletions.
diff --git a/elide-core/src/main/java/com/yahoo/elide/Elide.java b/elide-core/src/main/java/com/yahoo/elide/Elide.java
@@ -20,6 +20,7 @@
 import com.yahoo.elide.core.exceptions.InvalidURLException;
 import com.yahoo.elide.core.exceptions.JsonPatchExtensionException;
 import com.yahoo.elide.core.exceptions.TransactionException;
+import com.yahoo.elide.core.exceptions.UnableToAddSerdeException;
 import com.yahoo.elide.extensions.JsonApiPatch;
 import com.yahoo.elide.extensions.PatchRequestScope;
 import com.yahoo.elide.jsonapi.JsonApiMapper;
@@ -31,10 +32,18 @@
 import com.yahoo.elide.parsers.PatchVisitor;
 import com.yahoo.elide.parsers.PostVisitor;
 import com.yahoo.elide.security.User;
+import com.yahoo.elide.utils.ClassScanner;
 import com.yahoo.elide.utils.coerce.CoerceUtil;
+import com.yahoo.elide.utils.coerce.converters.ElideTypeConverter;
+import com.yahoo.elide.utils.coerce.converters.Serde;
 
+import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.module.SimpleModule;
 
 import org.antlr.v4.runtime.misc.ParseCancellationException;
 import org.apache.commons.lang3.StringUtils;
@@ -45,6 +54,8 @@
 import lombok.extern.slf4j.Slf4j;
 
 import java.io.IOException;
+import java.lang.reflect.InvocationTargetException;
+import java.util.Set;
 import java.util.function.Supplier;
 
 import javax.validation.ConstraintViolationException;
@@ -77,6 +88,60 @@ public Elide(ElideSettings elideSettings) {
         elideSettings.getSerdes().forEach((targetType, serde) -> {
             CoerceUtil.register(targetType, serde);
         });
+
+        registerCustomSerde();
+    }
+
+    private void registerCustomSerde() {
+        Set<Class<?>> classes = ClassScanner.getAnnotatedClasses(ElideTypeConverter.class);
+
+        for (Class<?> clazz : classes) {
+            if (!Serde.class.isAssignableFrom(clazz)) {
+                log.warn("Skipping Serde registration (not a Serde!): {}", clazz);
+                continue;
+            }
+            Serde serde;
+            try {
+                serde = (Serde) clazz
+                        .getDeclaredConstructor()
+                        .newInstance();
+            } catch (InstantiationException | IllegalAccessException
+                    | NoSuchMethodException | InvocationTargetException e) {
+                String errorMsg = String.format("Error while registering custom Serde: %s", e.getLocalizedMessage());
+                log.error(errorMsg);
+                throw new UnableToAddSerdeException(errorMsg);
+            }
+            ElideTypeConverter converter = clazz.getAnnotation(ElideTypeConverter.class);
+            Class baseType = converter.type();
+            registerCustomSerde(baseType, serde, converter.name());
+
+            for (Class type : converter.subTypes()) {
+                if (!baseType.isAssignableFrom(type)) {
+                    throw new IllegalArgumentException("Mentioned type " + type
+                            + " not subtype of " + baseType);
+                }
+                registerCustomSerde(type, serde, converter.name());
+            }
+        }
+    }
+
+    private void registerCustomSerde(Class<?> type, Serde serde, String name) {
+        log.info("Registering serde for type : {}", type);
+        CoerceUtil.register(type, serde);
+        registerCustomSerdeInObjectMapper(type, serde, name);
+    }
+
+    private void registerCustomSerdeInObjectMapper(Class<?> type, Serde serde, String name) {
+        ObjectMapper objectMapper = mapper.getObjectMapper();
+        objectMapper.registerModule(new SimpleModule(name)
+                .addSerializer(type, new JsonSerializer<Object>() {
+                    @Override
+                    public void serialize(Object obj, JsonGenerator jsonGenerator,
+                                          SerializerProvider serializerProvider)
+                            throws IOException, JsonProcessingException {
+                        jsonGenerator.writeObject(serde.serialize(obj));
+                    }
+                }));
     }
 
     /**

diff --git a/elide-core/src/main/java/com/yahoo/elide/core/exceptions/UnableToAddSerdeException.java b/elide-core/src/main/java/com/yahoo/elide/core/exceptions/UnableToAddSerdeException.java
@@ -0,0 +1,12 @@
+/*
+ * Copyright 2020, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.core.exceptions;
+
+public class UnableToAddSerdeException extends RuntimeException {
+    public UnableToAddSerdeException(String message) {
+        super(message);
+    }
+}
diff --git a/elide-core/src/main/java/com/yahoo/elide/utils/coerce/CoerceUtil.java b/elide-core/src/main/java/com/yahoo/elide/utils/coerce/CoerceUtil.java
@@ -78,6 +78,10 @@ public static <S, T> Serde<S, T> lookup(Class<T> targetType) {
         return (Serde<S, T>) SERDES.getOrDefault(targetType, null);
     }
 
+    public static Map<Class<?>, Serde<?, ?>> getSerdes() {
+        return Collections.unmodifiableMap(SERDES);
+    }
+
     /**
      * Perform CoerceUtil setup.
      */

diff --git a/elide-core/src/main/java/com/yahoo/elide/utils/coerce/converters/ElideTypeConverter.java b/elide-core/src/main/java/com/yahoo/elide/utils/coerce/converters/ElideTypeConverter.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2020, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.utils.coerce.converters;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface ElideTypeConverter {
+    Class<?> type();
+    String name();
+    String description() default "Custom Elide type";
+    Class<?> [] subTypes() default {};
+}
diff --git a/elide-core/src/main/java/com/yahoo/elide/utils/coerce/converters/OffsetDateTimeSerde.java b/elide-core/src/main/java/com/yahoo/elide/utils/coerce/converters/OffsetDateTimeSerde.java
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2020, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.utils.coerce.converters;
+
+import java.time.OffsetDateTime;
+import java.time.format.DateTimeFormatter;
+
+@ElideTypeConverter(type = OffsetDateTime.class, name = "OffsetDateTime")
+public class OffsetDateTimeSerde implements Serde<String, OffsetDateTime> {
+
+    @Override
+    public OffsetDateTime deserialize(String val) {
+        return OffsetDateTime.parse(val, DateTimeFormatter.ISO_OFFSET_DATE_TIME);
+    }
+
+    @Override
+    public String serialize(OffsetDateTime val) {
+        return val.format(DateTimeFormatter.ISO_OFFSET_DATE_TIME);
+    }
+}
diff --git a/elide-core/src/test/java/com/yahoo/elide/ElideCustomSerdeRegistrationTest.java b/elide-core/src/test/java/com/yahoo/elide/ElideCustomSerdeRegistrationTest.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2018, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import com.yahoo.elide.core.datastore.inmemory.HashMapDataStore;
+import com.yahoo.elide.core.datastore.inmemory.InMemoryDataStore;
+import com.yahoo.elide.utils.coerce.CoerceUtil;
+import com.yahoo.elide.utils.coerce.converters.ElideTypeConverter;
+import com.yahoo.elide.utils.coerce.converters.Serde;
+
+import org.junit.jupiter.api.Test;
+
+class Dummy {
+}
+
+class DummyTwo extends Dummy {
+}
+
+class DummyThree extends Dummy {
+}
+
+@ElideTypeConverter(type = Dummy.class, name = "Dummy", subTypes = {DummyThree.class, DummyTwo.class})
+class DummySerde implements Serde<String, Dummy> {
+
+    @Override
+    public Dummy deserialize(String val) {
+        return null;
+    }
+
+    @Override
+    public String serialize(Dummy val) {
+        return null;
+    }
+}
+
+public class ElideCustomSerdeRegistrationTest {
+    @Test
+    public void testRegisterCustomSerde() {
+        HashMapDataStore wrapped = new HashMapDataStore(Dummy.class.getPackage());
+        InMemoryDataStore store = new InMemoryDataStore(wrapped);
+        ElideSettings elideSettings = new ElideSettingsBuilder(store).build();
+        new Elide(elideSettings);
+        assertNotNull(CoerceUtil.lookup(Dummy.class));
+        assertNotNull(CoerceUtil.lookup(DummyTwo.class));
+        assertNotNull(CoerceUtil.lookup(DummyThree.class));
+    }
+}
diff --git a/elide-core/src/test/java/com/yahoo/elide/utils/coerce/converters/OffsetDateTimeTest.java b/elide-core/src/test/java/com/yahoo/elide/utils/coerce/converters/OffsetDateTimeTest.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2018, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.utils.coerce.converters;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.OffsetDateTime;
+import java.time.ZoneOffset;
+
+public class OffsetDateTimeTest {
+
+    @Test
+    public void testGraphQLOffsetDateTimeSerialize() {
+        OffsetDateTime offsetDateTime =
+                OffsetDateTime.of(1995, 11, 2,
+                        16, 45, 4, 56,
+                        ZoneOffset.ofHoursMinutes(5, 30));
+        String expected = "1995-11-02T16:45:04.000000056+05:30";
+        OffsetDateTimeSerde offsetDateTimeScalar = new OffsetDateTimeSerde();
+        Object actualDate = offsetDateTimeScalar.serialize(offsetDateTime);
+        assertEquals(expected, actualDate);
+    }
+
+    @Test
+    public void testGraphQLOffsetDateTimeDeserialize() {
+        OffsetDateTime actualDate =
+                OffsetDateTime.of(1995, 11, 2,
+                        16, 45, 4, 56,
+                        ZoneOffset.ofHoursMinutes(5, 30));
+        String actual = "1995-11-02T16:45:04.000000056+05:30";
+        OffsetDateTimeSerde offsetDateTimeScalar = new OffsetDateTimeSerde();
+        Object expected = offsetDateTimeScalar.deserialize(actual);
+        assertEquals(expected, actualDate);
+    }
+}
diff --git a/elide-graphql/src/main/java/com/yahoo/elide/graphql/GraphQLConversionUtils.java b/elide-graphql/src/main/java/com/yahoo/elide/graphql/GraphQLConversionUtils.java
@@ -13,6 +13,9 @@
 import static graphql.schema.GraphQLObjectType.newObject;
 
 import com.yahoo.elide.core.EntityDictionary;
+import com.yahoo.elide.utils.coerce.CoerceUtil;
+import com.yahoo.elide.utils.coerce.converters.ElideTypeConverter;
+import com.yahoo.elide.utils.coerce.converters.Serde;
 
 import graphql.Scalars;
 import graphql.schema.DataFetcher;
@@ -41,6 +44,9 @@ public class GraphQLConversionUtils {
     protected static final String MAP = "Map";
     protected static final String KEY = "key";
     protected static final String VALUE = "value";
+    protected static final String ERROR_MESSAGE = "Value should either be integer, String or float";
+
+    private final Map<Class<?>, GraphQLScalarType> scalarMap = new HashMap<>();
 
     protected NonEntityDictionary nonEntityDictionary = new NonEntityDictionary();
     protected EntityDictionary entityDictionary;
@@ -52,6 +58,20 @@ public class GraphQLConversionUtils {
 
     public GraphQLConversionUtils(EntityDictionary dictionary) {
         this.entityDictionary = dictionary;
+        registerCustomScalars();
+    }
+
+    private void registerCustomScalars() {
+        for (Class serdeType : CoerceUtil.getSerdes().keySet()) {
+            Serde serde = CoerceUtil.lookup(serdeType);
+            ElideTypeConverter elideTypeConverter = serde.getClass()
+                    .getAnnotation(ElideTypeConverter.class);
+            if (elideTypeConverter != null) {
+                SerdeCoercing serdeCoercing = new SerdeCoercing(ERROR_MESSAGE, serde);
+                scalarMap.put(elideTypeConverter.type(), new GraphQLScalarType(elideTypeConverter.name(),
+                        elideTypeConverter.description(), serdeCoercing));
+            }
+        }
     }
 
     /**
@@ -74,12 +94,13 @@ public GraphQLScalarType classToScalarType(Class<?> clazz) {
             return Scalars.GraphQLShort;
         } else if (clazz.equals(String.class)) {
             return Scalars.GraphQLString;
-        } else if (Date.class.isAssignableFrom(clazz)) {
-            return GraphQLScalars.GRAPHQL_DATE_TYPE;
         } else if (clazz.equals(BigDecimal.class)) {
             return Scalars.GraphQLBigDecimal;
+        } else if (Date.class.isAssignableFrom(clazz)) {
+            return GraphQLScalars.GRAPHQL_DATE_TYPE;
+        } else if (scalarMap.containsKey(clazz)) {
+            return scalarMap.get(clazz);
         }
-
         return null;
     }
 

diff --git a/elide-graphql/src/main/java/com/yahoo/elide/graphql/SerdeCoercing.java b/elide-graphql/src/main/java/com/yahoo/elide/graphql/SerdeCoercing.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2020, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.graphql;
+
+import com.yahoo.elide.utils.coerce.converters.Serde;
+
+import graphql.language.FloatValue;
+import graphql.language.IntValue;
+import graphql.language.StringValue;
+import graphql.schema.Coercing;
+import graphql.schema.CoercingParseValueException;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+@Data
+@AllArgsConstructor
+public class SerdeCoercing<I, O> implements Coercing<I, O> {
+    private String errorMessage;
+    private Serde<O, I> serde;
+
+    @Override
+    public O serialize(Object dataFetcherResult) {
+        return serde.serialize((I) dataFetcherResult);
+    }
+
+    @Override
+    public I parseValue(Object input) {
+        return serde.deserialize((O) input);
+    }
+
+    public I parseLiteral(Object o) {
+        Object input;
+        if (o instanceof IntValue) {
+            input = ((IntValue) o).getValue().longValue();
+        } else if (o instanceof StringValue) {
+            input = ((StringValue) o).getValue();
+        } else if (o instanceof FloatValue) {
+            input = ((FloatValue) o).getValue().floatValue();
+        } else {
+            throw new CoercingParseValueException(errorMessage);
+        }
+        return parseValue(input);
+    }
+}