org.mitre.openid.connect.config.JsonMessageSource.java Source code

Introduction

Here is the source code for org.mitre.openid.connect.config.JsonMessageSource.java

Source

/*******************************************************************************
 * Copyright 2016 The MITRE Corporation
 *   and the MIT Internet Trust Consortium
 *
 * 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 org.mitre.openid.connect.config;

import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.support.AbstractMessageSource;
import org.springframework.core.io.Resource;

import com.google.common.base.Splitter;
import com.google.gson.JsonElement;
import com.google.gson.JsonIOException;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import com.google.gson.JsonSyntaxException;

/**
 * @author jricher
 *
 */
public class JsonMessageSource extends AbstractMessageSource {
    // Logger for this class
    private static final Logger logger = LoggerFactory.getLogger(JsonMessageSource.class);

    private Resource baseDirectory;

    private Locale fallbackLocale = new Locale("en"); // US English is the fallback language

    private Map<Locale, List<JsonObject>> languageMaps = new HashMap<>();

    @Autowired
    private ConfigurationPropertiesBean config;

    @Override
    protected MessageFormat resolveCode(String code, Locale locale) {

        List<JsonObject> langs = getLanguageMap(locale);

        String value = getValue(code, langs);

        if (value == null) {
            // if we haven't found anything, try the default locale
            langs = getLanguageMap(fallbackLocale);
            value = getValue(code, langs);
        }

        if (value == null) {
            // if it's still null, return null
            return null;
        } else {
            // otherwise format the message
            return new MessageFormat(value, locale);
        }

    }

    /**
     * Get a value from the set of maps, taking the first match in order
     * @param code
     * @param langs
     * @return
     */
    private String getValue(String code, List<JsonObject> langs) {
        if (langs == null || langs.isEmpty()) {
            // no language maps, nothing to look up
            return null;
        }

        for (JsonObject lang : langs) {
            String value = getValue(code, lang);
            if (value != null) {
                // short circuit out of here if we find a match, otherwise keep going through the list
                return value;
            }
        }

        // if we didn't find anything return null
        return null;
    }

    /**
     * Get a value from a single map
     * @param code
     * @param locale
     * @param lang
     * @return
     */
    private String getValue(String code, JsonObject lang) {

        // if there's no language map, nothing to look up
        if (lang == null) {
            return null;
        }

        JsonElement e = lang;

        Iterable<String> parts = Splitter.on('.').split(code);
        Iterator<String> it = parts.iterator();

        String value = null;

        while (it.hasNext()) {
            String p = it.next();
            if (e.isJsonObject()) {
                JsonObject o = e.getAsJsonObject();
                if (o.has(p)) {
                    e = o.get(p); // found the next level
                    if (!it.hasNext()) {
                        // we've reached a leaf, grab it
                        if (e.isJsonPrimitive()) {
                            value = e.getAsString();
                        }
                    }
                } else {
                    // didn't find it, stop processing
                    break;
                }
            } else {
                // didn't find it, stop processing
                break;
            }
        }

        return value;

    }

    /**
     * @param locale
     * @return
     */
    private List<JsonObject> getLanguageMap(Locale locale) {

        if (!languageMaps.containsKey(locale)) {
            try {
                List<JsonObject> set = new ArrayList<>();
                for (String namespace : config.getLanguageNamespaces()) {
                    String filename = locale.getLanguage() + File.separator + namespace + ".json";

                    Resource r = getBaseDirectory().createRelative(filename);

                    logger.info("No locale loaded, trying to load from " + r);

                    JsonParser parser = new JsonParser();
                    JsonObject obj = (JsonObject) parser.parse(new InputStreamReader(r.getInputStream(), "UTF-8"));

                    set.add(obj);
                }
                languageMaps.put(locale, set);
            } catch (JsonIOException | JsonSyntaxException | IOException e) {
                logger.error("Unable to load locale", e);
            }
        }

        return languageMaps.get(locale);

    }

    /**
     * @return the baseDirectory
     */
    public Resource getBaseDirectory() {
        return baseDirectory;
    }

    /**
     * @param baseDirectory the baseDirectory to set
     */
    public void setBaseDirectory(Resource baseDirectory) {
        this.baseDirectory = baseDirectory;
    }

}