001/*
002 * Copyright 2012-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.boot;
018
019import java.io.PrintStream;
020import java.nio.charset.Charset;
021import java.nio.charset.StandardCharsets;
022import java.util.ArrayList;
023import java.util.Collections;
024import java.util.HashMap;
025import java.util.List;
026import java.util.Map;
027
028import org.apache.commons.logging.Log;
029import org.apache.commons.logging.LogFactory;
030
031import org.springframework.boot.ansi.AnsiPropertySource;
032import org.springframework.core.env.Environment;
033import org.springframework.core.env.MapPropertySource;
034import org.springframework.core.env.MutablePropertySources;
035import org.springframework.core.env.PropertyResolver;
036import org.springframework.core.env.PropertySourcesPropertyResolver;
037import org.springframework.core.io.Resource;
038import org.springframework.util.Assert;
039import org.springframework.util.StreamUtils;
040
041/**
042 * Banner implementation that prints from a source text {@link Resource}.
043 *
044 * @author Phillip Webb
045 * @author Vedran Pavic
046 * @since 1.2.0
047 */
048public class ResourceBanner implements Banner {
049
050        private static final Log logger = LogFactory.getLog(ResourceBanner.class);
051
052        private Resource resource;
053
054        public ResourceBanner(Resource resource) {
055                Assert.notNull(resource, "Resource must not be null");
056                Assert.isTrue(resource.exists(), "Resource must exist");
057                this.resource = resource;
058        }
059
060        @Override
061        public void printBanner(Environment environment, Class<?> sourceClass,
062                        PrintStream out) {
063                try {
064                        String banner = StreamUtils.copyToString(this.resource.getInputStream(),
065                                        environment.getProperty("spring.banner.charset", Charset.class,
066                                                        StandardCharsets.UTF_8));
067
068                        for (PropertyResolver resolver : getPropertyResolvers(environment,
069                                        sourceClass)) {
070                                banner = resolver.resolvePlaceholders(banner);
071                        }
072                        out.println(banner);
073                }
074                catch (Exception ex) {
075                        logger.warn("Banner not printable: " + this.resource + " (" + ex.getClass()
076                                        + ": '" + ex.getMessage() + "')", ex);
077                }
078        }
079
080        protected List<PropertyResolver> getPropertyResolvers(Environment environment,
081                        Class<?> sourceClass) {
082                List<PropertyResolver> resolvers = new ArrayList<>();
083                resolvers.add(environment);
084                resolvers.add(getVersionResolver(sourceClass));
085                resolvers.add(getAnsiResolver());
086                resolvers.add(getTitleResolver(sourceClass));
087                return resolvers;
088        }
089
090        private PropertyResolver getVersionResolver(Class<?> sourceClass) {
091                MutablePropertySources propertySources = new MutablePropertySources();
092                propertySources
093                                .addLast(new MapPropertySource("version", getVersionsMap(sourceClass)));
094                return new PropertySourcesPropertyResolver(propertySources);
095        }
096
097        private Map<String, Object> getVersionsMap(Class<?> sourceClass) {
098                String appVersion = getApplicationVersion(sourceClass);
099                String bootVersion = getBootVersion();
100                Map<String, Object> versions = new HashMap<>();
101                versions.put("application.version", getVersionString(appVersion, false));
102                versions.put("spring-boot.version", getVersionString(bootVersion, false));
103                versions.put("application.formatted-version", getVersionString(appVersion, true));
104                versions.put("spring-boot.formatted-version",
105                                getVersionString(bootVersion, true));
106                return versions;
107        }
108
109        protected String getApplicationVersion(Class<?> sourceClass) {
110                Package sourcePackage = (sourceClass != null) ? sourceClass.getPackage() : null;
111                return (sourcePackage != null) ? sourcePackage.getImplementationVersion() : null;
112        }
113
114        protected String getBootVersion() {
115                return SpringBootVersion.getVersion();
116        }
117
118        private String getVersionString(String version, boolean format) {
119                if (version == null) {
120                        return "";
121                }
122                return format ? " (v" + version + ")" : version;
123        }
124
125        private PropertyResolver getAnsiResolver() {
126                MutablePropertySources sources = new MutablePropertySources();
127                sources.addFirst(new AnsiPropertySource("ansi", true));
128                return new PropertySourcesPropertyResolver(sources);
129        }
130
131        private PropertyResolver getTitleResolver(Class<?> sourceClass) {
132                MutablePropertySources sources = new MutablePropertySources();
133                String applicationTitle = getApplicationTitle(sourceClass);
134                Map<String, Object> titleMap = Collections.singletonMap("application.title",
135                                (applicationTitle != null) ? applicationTitle : "");
136                sources.addFirst(new MapPropertySource("title", titleMap));
137                return new PropertySourcesPropertyResolver(sources);
138        }
139
140        protected String getApplicationTitle(Class<?> sourceClass) {
141                Package sourcePackage = (sourceClass != null) ? sourceClass.getPackage() : null;
142                return (sourcePackage != null) ? sourcePackage.getImplementationTitle() : null;
143        }
144
145}