Question

我试图在lagom服务中设置jdbc读取端处理器：

class ProjectEventsProcessor(readSide: JdbcReadSide)(implicit ec: ExecutionContext) extends ReadSideProcessor[ProjectEvent] {

  def buildHandler = {
    readSide.builder[ProjectEvent]("projectEventOffset")
      .setEventHandler[ProjectCreated]((conn: Connection, e: EventStreamElement[ProjectCreated]) => insertProject(e.event))
      .build
  }

  private def insertProject(e: ProjectCreated) = {
    Logger.info(s"Got event $e")
  }

  override def aggregateTags: Set[AggregateEventTag[ProjectEvent]] = ProjectEvent.Tag.allTags
}

服务在启动时连接到数据库 15:40:32.575 [info] play.api.db.DefaultDBApi [] - Database [default] connected at jdbc:postgresql://localhost/postgres?user=postgres

但在此之后我才得到例外。

com.typesafe.config.ConfigException $ Missing：没有配置设置找到关键＆＃39; slick.profile＆＃39;

首先，为什么这里涉及光滑？

我使用JdbcReadSide但不使用SlickReadSide。

好吧，让我们说JdbcReadSide内部以某种方式使用光滑。

我已在我的服务的application.config中添加了slick.profile。

db.default.driver="org.postgresql.Driver"
db.default.url="jdbc:postgresql://localhost/postgres?user=postgres"

// Tried this way
slick.profile="slick.jdbc.PostgresProfile$" 

// Also this fay (copied from play documentation).
slick.dbs.default.profile="slick.jdbc.PostgresProfile$"
slick.dbs.default.db.dataSourceClass = "slick.jdbc.DatabaseUrlDataSource"
slick.dbs.default.db.properties.driver = "org.postgresql.Driver"

但仍然有这个例外。

发生了什么事？如何解决这个问题？

Answer 1

根据docs，拉各姆使用akka-persistence-jdbc，该词在幕后：

使用Slick映射表并管理JDBC调用的异步执行。

以下是完整配置，同时还使用默认连接池（HikariCP）在application.conf文件中进行了设置（大部分是从文档复制的）：

# Defaults to use for each Akka persistence plugin
jdbc-defaults.slick {

  # The Slick profile to use
  # set to one of: slick.jdbc.PostgresProfile$, slick.jdbc.MySQLProfile$, slick.jdbc.OracleProfile$ or slick.jdbc.H2Profile$
  profile = "slick.jdbc.PostgresProfile$"

  # The JNDI name for the Slick pre-configured DB
  # By default, this value will be used by all akka-persistence-jdbc plugin components (journal, read-journal and snapshot).
  # you may configure each plugin component to use different DB settings
  jndiDbName=DefaultDB
}


db.default {

  driver = "org.postgresql.Driver"
  url = "jdbc:postgresql://localhost/postgres?user=postgres"

  # The JNDI name for this DataSource
  # Play, and therefore Lagom, will automatically register this DataSource as a JNDI resource using this name.
  # This DataSource will be used to build a pre-configured Slick DB
  jndiName=DefaultDS

  # Lagom will configure a Slick Database, using the async-executor settings below
  # and register it as a JNDI resource using this name.
  # By default, all akka-persistence-jdbc plugin components will use this JDNI name
  # to lookup for this pre-configured Slick DB
  jndiDbName=DefaultDB

  async-executor {
    # number of objects that can be queued by the async executor
    queueSize = 10000

    # 5 * number of cores
    numThreads = 20

    # same as number of threads
    minConnections = 20

    # same as number of threads
    maxConnections = 20

    # if true, a Mbean for AsyncExecutor will be registered
    registerMbeans = false
  }

  # Hikari is the default connection pool and it's fine-tuned to use the same
  # values for minimum and maximum connections as defined for the async-executor above
  hikaricp {
    minimumIdle = ${db.default.async-executor.minConnections}
    maximumPoolSize = ${db.default.async-executor.maxConnections}
  }
}


lagom.persistence.jdbc {

  # Configuration for creating tables
  create-tables {

    # Whether tables should be created automatically as needed
    auto = true

    # How long to wait for tables to be created, before failing
    timeout = 20s

    # The cluster role to create tables from
    run-on-role = ""

    # Exponential backoff for failures configuration for creating tables
    failure-exponential-backoff {

      # minimum (initial) duration until processor is started again
      # after failure
      min = 3s

      # the exponential back-off is capped to this duration
      max = 30s

      # additional random delay is based on this factor
      random-factor = 0.2
    }
  }
}

Lagom Jdbc Read-Side支持：com.typesafe.config.ConfigException $ Missing：找不到关键＆＃39; slick.profile＆＃39;

1 个答案: