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/** * 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.component.docker; import java.lang.reflect.Array; import java.util.HashMap; import java.util.Map; import com.github.dockerjava.api.DockerClientException; import org.apache.camel.Message; import org.apache.camel.util.ObjectHelper; import org.apache.commons.lang.BooleanUtils; /** * Utility methods for Docker Component */ public final class DockerHelper { private static final String STRING_DELIMITER = ";"; private DockerHelper() { //Helpser class } /** * Validates the URI parameters for a given {@link DockerOperation} * * @param dockerOperation * @param parameters */ public static void validateParameters(DockerOperation dockerOperation, Map<String, Object> parameters) { Map<String, Class<?>> validParamMap = new HashMap<String, Class<?>>(); validParamMap.putAll(DockerConstants.DOCKER_DEFAULT_PARAMETERS); validParamMap.putAll(dockerOperation.getParameters()); for (String key : parameters.keySet()) { String transformedKey = DockerHelper.transformToHeaderName(key); // Validate URI parameter name if (!validParamMap.containsKey(transformedKey)) { throw new DockerClientException(key + " is not a valid URI parameter"); } try { Class<?> parameterClass = validParamMap.get(transformedKey); Object parameterValue = parameters.get(key); if (parameterClass == null || parameterValue == null) { throw new DockerClientException("Failed to validate parameter type for property " + key); } if (Integer.class == parameterClass) { Integer.parseInt((String) parameterValue); } else if (Boolean.class == parameterClass) { BooleanUtils.toBooleanObject((String) parameterValue, "true", "false", "null"); } } catch (Exception e) { throw new DockerClientException("Failed to validate parameter type for property " + key); } } } /** * Transforms a Docker Component header value to its' analogous URI parameter * * @param name * @return */ public static String transformFromHeaderName(String name) { ObjectHelper.notEmpty(name, "name"); StringBuilder formattedName = new StringBuilder(); String nameSubstring = name.substring(DockerConstants.DOCKER_PREFIX.length()); if (nameSubstring.length() > 0) { formattedName.append(nameSubstring.substring(0, 1).toLowerCase()); formattedName.append(nameSubstring.substring(1)); } return formattedName.toString(); } /** * Transforms a Docker Component URI parameter to its' analogous header value * * @param name * @return */ public static String transformToHeaderName(String name) { ObjectHelper.notEmpty(name, "name"); StringBuilder formattedName = new StringBuilder(DockerConstants.DOCKER_PREFIX); if (name.length() > 0) { formattedName.append(name.substring(0, 1).toUpperCase()); formattedName.append(name.substring(1)); } return formattedName.toString(); } /** * Attempts to locate a given property name within a URI parameter or the message header. * A found value in a message header takes precedence over a URI parameter. * * @param name * @param configuration * @param message * @param clazz * @return */ public static <T> T getProperty(String name, DockerConfiguration configuration, Message message, Class<T> clazz) { return getProperty(name, configuration, message, clazz, null); } /** * Attempts to locate a given property name within a URI parameter or the message header. * A found value in a message header takes precedence over a URI parameter. Returns a * default value if given * * @param name * @param configuration * @param message * @param clazz * @param defaultValue * @return */ @SuppressWarnings("unchecked") public static <T> T getProperty(String name, DockerConfiguration configuration, Message message, Class<T> clazz, T defaultValue) { // First attempt to locate property from Message Header, then fallback to Endpoint property if (message != null) { T headerProperty = message.getHeader(name, clazz); if (headerProperty != null) { return headerProperty; } } Object prop = configuration.getParameters().get(transformFromHeaderName(name)); if (prop != null) { if (prop.getClass().isAssignableFrom(clazz)) { return (T) prop; } else if (Integer.class == clazz) { return (T) Integer.valueOf((String) prop); } else if (Boolean.class == clazz) { return (T) BooleanUtils.toBooleanObject((String) prop, "true", "false", "null"); } } else if (defaultValue != null) { return defaultValue; } return null; } /** * Attempts to locate a given property which is an array by name within a URI parameter or the message header. * A found value in a message header takes precedence over a URI parameter. * * @param name * @param message * @param clazz * @return */ @SuppressWarnings("unchecked") public static <T> T[] getArrayProperty(String name, Message message, Class<T> clazz) { if (message != null) { Object header = message.getHeader(name); if (header != null) { if (header.getClass().isAssignableFrom(clazz)) { T[] headerArray = (T[]) Array.newInstance(clazz, 1); headerArray[0] = (T) header; return headerArray; } if (header.getClass().isArray()) { if (header.getClass().getComponentType().isAssignableFrom(clazz) || header.getClass().getDeclaringClass().isAssignableFrom(clazz)) { return (T[]) header; } } } } return null; } /** * @param headerName name of the header * @param message the Camel message * @return */ public static String[] parseDelimitedStringHeader(String headerName, Message message) { Object header = message.getHeader(headerName); if (header != null) { if (header instanceof String) { return ((String) header).split(STRING_DELIMITER); } if (header instanceof String[]) { return (String[]) header; } } return null; } }