Question

我已经在我的user-impl服务中创建了一个用户存储库Lagom readside，但是由于某些原因，运行sbt lagom:runAll时未创建Cassandra users表。我不确定我在这里缺少什么。

我的UserRepository类：

@Singleton
public class UserRepository {

    private final CassandraSession session;

    @Inject
    public UserRepository(CassandraSession session, ReadSide readSide) {
        this.session = session;
        readSide.register(PUserEventProcessor.class);
    }

    private static class PUserEventProcessor extends ReadSideProcessor<PUserEvent> {

        private final CassandraSession session;
        private final CassandraReadSide readSide;

        private PreparedStatement insertUserStatement;
        private PreparedStatement updateUserStatement;

        @Inject
        public PUserEventProcessor(CassandraSession session, CassandraReadSide readSide) {
            this.session = session;
            this.readSide = readSide;
        }

        @Override
        public ReadSideHandler<PUserEvent> buildHandler() {
            return readSide.<PUserEvent>builder("pUserEventOffset")
                    .setGlobalPrepare(this::createTables)
                    .setPrepare(tag -> prepareStatements())
                    .setEventHandler(PUserEvent.PUserCreated.class,
                            e -> insertUser(e.getUser()))
                    .setEventHandler(PUserEvent.PUserUpdated.class,
                            e -> updateUser(e.getUser()))
                    .build();
        }

        private void registerCodec(Session session, InstantCodec codec) {
            session.getCluster().getConfiguration().getCodecRegistry().register(codec);
        }

        @Override
        public PSequence<AggregateEventTag<PUserEvent>> aggregateTags() {
            return PUserEvent.TAG.allTags();
        }

        private CompletionStage<Done> createTables() {
            return doAll(
                    session.executeCreateTable(
                            "CREATE TABLE IF NOT EXISTS users (" +
                                    "userId UUID, " +
                                    "email text, " +
                                    "firstName text, " +
                                    "lastName text, " +
                                    "gender text, " +
                                    "PRIMARY KEY (userId) " +
                                    ")"
                    )
            );
        }

        private CompletionStage<Done> prepareStatements() {
            return doAll(
                    session.underlying()
                            .thenAccept(s -> registerCodec(s, InstantCodec.instance))
                            .thenApply(x -> Done.getInstance()),
                    prepareInsertUserStatement(),
                    prepareUpdateUserStatement());
        }


        // Insert users

        private CompletionStage<Done> prepareInsertUserStatement() {
            return session.
                    prepare("INSERT INTO users(" +
                            "userId, " +
                            "email" +
                            "firstName, " +
                            "lastName, " +
                            "gender, " +
                            "refreshToken" +
                            ") " +
                            "VALUES (?, ?, ?, ?, ?, ?)"
                    )
                    .thenApply(accept(s -> insertUserStatement = s));
        }


        private CompletionStage<List<BoundStatement>> insertUser(DbUser user) {
            return completedStatements(
                    insertUserCreator(user)
            );
        }

        private BoundStatement insertUserCreator(DbUser user) {
            return insertUserStatement.bind(
                    user.getUserId(),
                    user.getEmail(),
                    user.getFirstName(),
                    user.getLastName(),
                    user.getGender(),
                    user.getRefreshToken()
            );
        }

        // Update user by userId

        private CompletionStage<Done> prepareUpdateUserStatement() {
            return session.
                    prepare("UPDATE users " +
                            "SET email = ?, " +
                            "   firstName = ?, " +
                            "   lastName = ?, " +
                            "   gender = ?, " +
                            "   refreshToken = ?" +
                            "WHERE userId = ?;"
                    )
                    .thenApply(accept(s -> updateUserStatement = s));
        }


        private CompletionStage<List<BoundStatement>> updateUser(DbUser user) {
            return completedStatements(
                    updateUserCreator(user)
            );
        }

        private BoundStatement updateUserCreator(DbUser user) {
            return updateUserStatement.bind(
                    user.getEmail(),
                    user.getFirstName(),
                    user.getLastName(),
                    user.getGender(),
                    user.getUserId(),
                    user.getRefreshToken()
            );
        }

    }
}

已添加到UserModule.java：

public class UserModule extends AbstractModule implements ServiceGuiceSupport {

    @Override
    protected void configure() {
        bindService(UserService.class, UserServiceImpl.class);
        bind(UserRepository.class);
    }
}

application.conf：

play.modules.enabled += UserModule
lagom.persistence.ask-timeout = 1000s

user.cassandra.keyspace = user

cassandra-journal.keyspace = ${user.cassandra.keyspace}
cassandra-snapshot-store.keyspace = ${user.cassandra.keyspace}
lagom.persistence.read-side.cassandra.keyspace = ${user.cassandra.keyspace}

我的设置是标准设置：

“用户”表已创建，消息表甚至存储了事件。
为什么不显示“用户”表或如何进行故障排除有什么帮助？

这让我发疯。
启动服务时没有错误抛出，检查了lagom-auction示例，并且那里的键空间可用。我看不出代码有什么区别...

编辑：尝试获取我的表： -sbt clean /手动删除嵌入式cassandra -将lagom-sbt-plugin升级到1.4.8

非常感谢帮助甚至技巧。没有阅读面就不能做很多事，哈哈。

Answer 1

您需要将result_array = [{ "date": 1533791167870, "count": 1, "name": "James" }, { "date": 1533791167870, "count": 3, "name": "Kane" }, { "date": 1533791167870, "count": 0, "name": "Trent" }, { "date": 1533791167870, "count": 0, "name": "Sam" }, { "date": 1533791167918, "count": 0, "name": "James" }, { "date": 1533791167918, "count": 1, "name": "Kane" }, { "date": 1533791167918, "count": 0, "name": "Sam" }, { "date": 1533791167918, "count": 0, "name": "Trent" }, { "date": 1536203856526, "count": 0, "name": "James" }, { "date": 1536203856526, "count": 0, "name": "Kane" }, { "date": 1536203856526, "count": 2, "name": "Trent" }, { "date": 1536203856526, "count": 0, "name": "Sam" }, { "date": 1536217871371, "count": 0, "name": "James" }, { "date": 1536217871371, "count": 5, "name": "Kane" }, { "date": 1536217871371, "count": 5, "name": "Trent" }, { "date": 1536217871371, "count": 5, "name": "Sam" }, { "date": 1536217882525, "count": 4, "name": "James" }, { "date": 1536217882525, "count": 0, "name": "Trent" }, { "date": 1536217882525, "count": 0, "name": "Sam" }, { "date": 1536217882525, "count": 0, "name": "Kane" } ]绑定为eager singleton。这将强制初始化不延迟。您会注意到，它在产品中无关紧要，但对于开发而言却无关紧要（这可能就是为什么您在开发人员中看到此问题的原因。）

有关示例，请参见online auction。

未创建Lagom Cassandra readside表

1 个答案: