org.eclipse.hono.deviceregistry.FileBasedCredentialsService.java Source code

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Here is the source code for org.eclipse.hono.deviceregistry.FileBasedCredentialsService.java

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/**
 * Copyright (c) 2017 Bosch Software Innovations GmbH.
 * <p>
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * <p>
 * Contributors:
 * Bosch Software Innovations GmbH - initial creation
 */

package org.eclipse.hono.deviceregistry;

import io.vertx.core.AsyncResult;
import io.vertx.core.Future;
import io.vertx.core.Handler;
import io.vertx.core.buffer.Buffer;
import io.vertx.core.file.FileSystem;
import io.vertx.core.json.JsonArray;
import io.vertx.core.json.JsonObject;
import org.eclipse.hono.service.credentials.BaseCredentialsService;
import org.eclipse.hono.util.CredentialsResult;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicInteger;

import static java.net.HttpURLConnection.*;
import static org.eclipse.hono.util.CredentialsConstants.*;

/**
 * A credentials service that keeps all data in memory but is backed by a file.
 * <p>
 * On startup this adapter loads all added credentials from a file. On shutdown all
 * credentials kept in memory are written to the file.
 */
@Repository
public final class FileBasedCredentialsService
        extends BaseCredentialsService<FileBasedCredentialsConfigProperties> {

    private static final String ARRAY_CREDENTIALS = "credentials";
    private static final String FIELD_TENANT = "tenant";

    // <tenantId, <authId, credentialsData[]>>
    private Map<String, Map<String, JsonArray>> credentials = new HashMap<>();
    private boolean running = false;
    private boolean dirty = false;

    @Autowired
    @Override
    public void setConfig(final FileBasedCredentialsConfigProperties configuration) {
        setSpecificConfig(configuration);
    }

    @Override
    protected void doStart(final Future<Void> startFuture) throws Exception {
        if (!running) {
            loadCredentials().compose(s -> {
                if (getConfig().isSaveToFile()) {
                    log.info("saving credentials to file every 3 seconds");
                    vertx.setPeriodic(3000, saveIdentities -> {
                        saveToFile(Future.future());
                    });
                } else {
                    log.info("persistence is disabled, will not save credentials to file");
                }
                running = true;
                startFuture.complete();
            }, startFuture);
        } else {
            startFuture.complete();
        }
    }

    Future<Void> loadCredentials() {
        Future<Void> result = Future.future();
        if (getConfig().getCredentialsFilename() == null) {
            result.fail(new IllegalStateException("credentials filename is not set"));
        } else {
            final FileSystem fs = vertx.fileSystem();
            log.debug("trying to load credentials information from file {}", getConfig().getCredentialsFilename());

            if (fs.existsBlocking(getConfig().getCredentialsFilename())) {
                log.info("loading credentials from file [{}]", getConfig().getCredentialsFilename());
                fs.readFile(getConfig().getCredentialsFilename(), readAttempt -> {
                    if (readAttempt.succeeded()) {
                        JsonArray allObjects = readAttempt.result().toJsonArray();
                        parseCredentials(allObjects);
                        result.complete();
                    } else {
                        result.fail(readAttempt.cause());
                    }
                });
            } else {
                log.debug("credentials file [{}] does not exist (yet)", getConfig().getCredentialsFilename());
                result.complete();
            }
        }
        return result;
    }

    private void parseCredentials(final JsonArray credentialsObject) {
        final AtomicInteger credentialsCount = new AtomicInteger();

        log.debug("trying to load credentials for {} tenants", credentialsObject.size());
        for (Object obj : credentialsObject) {
            JsonObject tenant = (JsonObject) obj;
            String tenantId = tenant.getString(FIELD_TENANT);
            Map<String, JsonArray> credentialsMap = new HashMap<>();
            for (Object credentialsObj : tenant.getJsonArray(ARRAY_CREDENTIALS)) {
                JsonObject credentials = (JsonObject) credentialsObj;
                JsonArray authIdCredentials;
                if (credentialsMap.containsKey(credentials.getString(FIELD_AUTH_ID))) {
                    authIdCredentials = credentialsMap.get(credentials.getString(FIELD_AUTH_ID));
                } else {
                    authIdCredentials = new JsonArray();
                }
                authIdCredentials.add(credentials);
                credentialsMap.put(credentials.getString(FIELD_AUTH_ID), authIdCredentials);
                credentialsCount.incrementAndGet();
            }
            credentials.put(tenantId, credentialsMap);
        }
        log.info("successfully loaded {} credentials from file [{}]", credentialsCount.get(),
                getConfig().getCredentialsFilename());
    }

    @Override
    protected void doStop(final Future<Void> stopFuture) {

        if (running) {
            Future<Void> stopTracker = Future.future();
            stopTracker.setHandler(stopAttempt -> {
                running = false;
                stopFuture.complete();
            });

            if (getConfig().isSaveToFile()) {
                saveToFile(stopTracker);
            } else {
                stopTracker.complete();
            }
        } else {
            stopFuture.complete();
        }
    }

    private void saveToFile(final Future<Void> writeResult) {

        if (!dirty) {
            log.trace("credentials registry does not need to be persisted");
            return;
        }

        final FileSystem fs = vertx.fileSystem();
        String filename = getConfig().getCredentialsFilename();

        if (!fs.existsBlocking(filename)) {
            fs.createFileBlocking(filename);
        }
        final AtomicInteger idCount = new AtomicInteger();
        JsonArray tenants = new JsonArray();
        for (Entry<String, Map<String, JsonArray>> entry : credentials.entrySet()) {
            JsonArray credentialsArray = new JsonArray();
            for (Entry<String, JsonArray> credentialEntry : entry.getValue().entrySet()) { // authId -> full json attributes object
                JsonArray singleAuthIdCredentials = credentialEntry.getValue(); // from one authId
                credentialsArray.addAll(singleAuthIdCredentials);
                idCount.incrementAndGet();
            }
            tenants.add(
                    new JsonObject().put(FIELD_TENANT, entry.getKey()).put(ARRAY_CREDENTIALS, credentialsArray));
        }
        fs.writeFile(getConfig().getCredentialsFilename(), Buffer.factory.buffer(tenants.encodePrettily()),
                writeAttempt -> {
                    if (writeAttempt.succeeded()) {
                        dirty = false;
                        log.trace("successfully wrote {} credentials to file {}", idCount.get(), filename);
                        writeResult.complete();
                    } else {
                        log.warn("could not write credentials to file {}", filename, writeAttempt.cause());
                        writeResult.fail(writeAttempt.cause());
                    }
                });
    }

    @Override
    public final void getCredentials(final String tenantId, final String type, final String authId,
            final Handler<AsyncResult<CredentialsResult<JsonObject>>> resultHandler) {
        CredentialsResult<JsonObject> credentialsResult = getCredentialsResult(tenantId, authId, type);
        resultHandler.handle(Future.succeededFuture(credentialsResult));
    }

    private CredentialsResult<JsonObject> getCredentialsResult(final String tenantId, final String authId,
            final String type) {
        JsonObject data = getCredentials(tenantId, authId, type);
        if (data != null) {
            JsonObject resultPayload = getResultPayload(data.getString(FIELD_DEVICE_ID), data.getString(FIELD_TYPE),
                    data.getString(FIELD_AUTH_ID), data.getBoolean(FIELD_ENABLED),
                    data.getJsonArray(FIELD_SECRETS));
            return CredentialsResult.from(HTTP_OK, resultPayload);
        } else {
            return CredentialsResult.from(HTTP_NOT_FOUND, (JsonObject) null);
        }
    }

    private JsonObject getCredentials(final String tenantId, final String authId, final String type) {
        Objects.requireNonNull(tenantId);
        Objects.requireNonNull(authId);
        Objects.requireNonNull(type);

        final Map<String, JsonArray> credentialsForTenant = credentials.get(tenantId);
        if (credentialsForTenant != null) {
            JsonArray authIdCredentials = credentialsForTenant.get(authId);
            if (authIdCredentials == null) {
                return null;
            }

            for (Object authIdCredentialEntry : authIdCredentials) {
                JsonObject authIdCredential = (JsonObject) authIdCredentialEntry;
                // return the first matching type entry for this authId
                if (type.equals(authIdCredential.getString(FIELD_TYPE))) {
                    return authIdCredential;
                }
            }
        }
        return null;
    }

    /**
     * Removes all credentials from the registry.
     */
    public final void clear() {
        dirty = true;
        credentials.clear();
    }

    @Override
    public String toString() {
        return String.format("%s[filename=%s]", FileBasedCredentialsService.class.getSimpleName(),
                getConfig().getCredentialsFilename());
    }
}