ResponseUtils.java

/*
   Copyright (c) 2014 LinkedIn Corp.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package com.linkedin.restli.internal.common;


import com.linkedin.data.DataList;
import com.linkedin.data.DataMap;
import com.linkedin.data.collections.CheckedUtil;
import com.linkedin.data.schema.DataSchema;
import com.linkedin.data.schema.DataSchemaUtil;
import com.linkedin.data.schema.TyperefDataSchema;
import com.linkedin.data.template.DataTemplateUtil;
import com.linkedin.data.template.RecordTemplate;
import com.linkedin.data.template.TyperefInfo;
import com.linkedin.jersey.api.uri.UriComponent;
import com.linkedin.restli.common.ComplexKeySpec;
import com.linkedin.restli.common.ComplexResourceKey;
import com.linkedin.restli.common.CompoundKey;
import com.linkedin.restli.common.ProtocolVersion;
import com.linkedin.restli.common.TypeSpec;
import com.linkedin.util.CustomTypeUtil;

import java.util.List;
import java.util.Map;


/**
 * Utilities for key-typed responses
 */
public class ResponseUtils
{
  public static Object convertKey(String rawKey,
                                 TypeSpec<?> keyType,
                                 Map<String, CompoundKey.TypeInfo> keyParts,
                                 ComplexKeySpec<?, ?> complexKeyType,
                                 ProtocolVersion version)
  {
    Class<?> keyBindingClass = keyType.getType();
    Object result;

    if (TyperefInfo.class.isAssignableFrom(keyType.getType()))
    {
      TyperefDataSchema schema = (TyperefDataSchema)keyType.getSchema();
      if (!schema.getDereferencedDataSchema().isPrimitive())
      {
        throw new IllegalArgumentException("Typeref must reference a primitive type when used as a key type.");
      }

      // Coerce the raw key string to the referenced primitive type.
      DataSchema.Type dereferencedType = schema.getDereferencedType();
      Class<?> primitiveClass = DataSchemaUtil.dataSchemaTypeToPrimitiveDataSchemaClass(dereferencedType);
      result = ValueConverter.coerceString(rawKey, primitiveClass);

      // Identify the binding class for the typeref.
      keyBindingClass = CustomTypeUtil.getJavaCustomTypeClassFromSchema(schema);
      if(keyBindingClass == null)
      {
        keyBindingClass = primitiveClass;
      }
    }
    else if (CompoundKey.class.isAssignableFrom(keyType.getType()))
    {
      DataMap keyDataMap;
      if (version.compareTo(AllProtocolVersions.RESTLI_PROTOCOL_2_0_0.getProtocolVersion()) >= 0)
      {
        try
        {
          keyDataMap = (DataMap) URIElementParser.parse(rawKey);
        }
        catch (PathSegment.PathSegmentSyntaxException e)
        {
          throw new IllegalStateException(rawKey + " is not a valid value for the resource key", e);
        }
      }
      else
      {
        keyDataMap = parseKey(rawKey);
      }

      result = CompoundKey.fromValues(keyDataMap, keyParts);
    }
    else if (ComplexResourceKey.class.isAssignableFrom(keyType.getType()))
    {
      try
      {
        ComplexResourceKey<RecordTemplate, RecordTemplate> complexResourceKey =
                ComplexResourceKey.parseString(rawKey, complexKeyType, version);
        result = QueryParamsDataMap.fixUpComplexKeySingletonArray(complexResourceKey);
      }
      catch (PathSegment.PathSegmentSyntaxException e)
      {
        throw new IllegalStateException(rawKey + " is not a valid value for the resource key", e);
      }
    }
    else
    {
      try
      {
        result = ValueConverter.coerceString(rawKey, keyType.getType());
      }
      catch (IllegalArgumentException e)
      {
        throw new IllegalStateException(rawKey + " is not a valid value for resource key type " + keyType.getType().getName(), e);
      }
    }

    return DataTemplateUtil.coerceOutput(result, keyBindingClass);
  }

  //TODO: replace with generic QueryParam <=> DataMap codec
  private static DataMap parseKey(String rawKey)
  {
    Map<String, List<String>> fields = UriComponent.decodeQuery(rawKey, true);
    DataMap result = new DataMap((int)Math.ceil(fields.size()/0.75f));
    for (Map.Entry<String, List<String>> entry : fields.entrySet())
    {
      if (entry.getValue().size() == 1)
      {
        result.put(entry.getKey(), entry.getValue().get(0));
      }
      else
      {
        CheckedUtil.putWithoutChecking(result, entry.getKey(), new DataList(entry.getValue()));
      }
    }
    return result;
  }
}