camel-k-loader-yaml/src/main/java/org/apache/camel/k/loader/yaml/model/Step.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.camel.k.loader.yaml.model;

import java.io.IOException;
import java.util.Map;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;

@JsonDeserialize(using = Step.Deserializer.class)
public final class Step {
    public final String id;
    public final JsonNode node;

    public Step(String id, JsonNode node) {
        this.id = id;
        this.node = node;
    }

    public static class Deserializer extends StdDeserializer<Step> {
        public Deserializer() {
            this(null);
        }

        protected Deserializer(Class<?> vc) {
            super(vc);
        }

        @Override
        public Step deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
            JsonNode node = p.getCodec().readTree(p);

            if (node.size() != 1) {
                throw new IllegalStateException("Step should not have more tha one child");
            }

            final Map.Entry<String, JsonNode> field = node.fields().next();
            final String stepId = field.getKey();
            final JsonNode stepData = field.getValue();

            return new Step(stepId, stepData);
        }
    }

    // marker interface
    public interface Definition {
    }
}