Scala Repo Server: make app crash instead of hanging when run with no arguments

[alexanderdean]

Doesn't crash but just hangs indefinitely:

$ java -jar iglu-server-0.2.0-rc1
Exception in thread "main" java.lang.ExceptionInInitializerError
    at com.snowplowanalytics.iglu.server.Boot.main(Boot.scala)
Caused by: org.postgresql.util.PSQLException: Connection refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
    at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:207)
    at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:64)
    at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:136)
    at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:29)
    at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:21)
    at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:31)
    at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
    at org.postgresql.Driver.makeConnection(Driver.java:410)
    at org.postgresql.Driver.connect(Driver.java:280)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:187)
    at scala.slick.jdbc.JdbcBackend$DatabaseFactoryDef$$anon$4.createConnection(JdbcBackend.scala:70)
    at scala.slick.jdbc.JdbcBackend$BaseSession.conn$lzycompute(JdbcBackend.scala:397)
    at scala.slick.jdbc.JdbcBackend$BaseSession.conn(JdbcBackend.scala:397)
    at scala.slick.jdbc.JdbcBackend$BaseSession.metaData$lzycompute(JdbcBackend.scala:398)
    at scala.slick.jdbc.JdbcBackend$BaseSession.metaData(JdbcBackend.scala:398)
    at scala.slick.jdbc.meta.MTable$$anonfun$getTables$1.apply(MTable.scala:26)
    at scala.slick.jdbc.meta.MTable$$anonfun$getTables$1.apply(MTable.scala:26)
    at scala.slick.jdbc.ResultSetInvoker$$anon$3.createResultSet(ResultSetInvoker.scala:34)
    at scala.slick.jdbc.ResultSetInvoker.iteratorTo(ResultSetInvoker.scala:17)
    at scala.slick.jdbc.Invoker$class.foreach(Invoker.scala:64)
    at scala.slick.jdbc.ResultSetInvoker.foreach(ResultSetInvoker.scala:12)
    at scala.slick.jdbc.Invoker$class.build(Invoker.scala:47)
    at scala.slick.jdbc.ResultSetInvoker.build(ResultSetInvoker.scala:12)
    at scala.slick.jdbc.Invoker$class.list(Invoker.scala:39)
    at scala.slick.jdbc.ResultSetInvoker.list(ResultSetInvoker.scala:12)
    at com.snowplowanalytics.iglu.server.TableInitialization$$anonfun$initializeTables$1.apply$mcV$sp(Core.scala:70)
    at com.snowplowanalytics.iglu.server.TableInitialization$$anonfun$initializeTables$1.apply(Core.scala:69)
    at com.snowplowanalytics.iglu.server.TableInitialization$$anonfun$initializeTables$1.apply(Core.scala:69)
    at scala.util.DynamicVariable.withValue(DynamicVariable.scala:57)
    at scala.slick.backend.DatabaseComponent$class.withDynamicSession(DatabaseComponent.scala:67)
    at scala.slick.jdbc.JdbcBackend$.withDynamicSession(JdbcBackend.scala:448)
    at scala.slick.backend.DatabaseComponent$DatabaseDef$$anonfun$withDynSession$1.apply(DatabaseComponent.scala:51)
    at scala.slick.backend.DatabaseComponent$DatabaseDef$$anonfun$withDynSession$1.apply(DatabaseComponent.scala:51)
    at scala.slick.backend.DatabaseComponent$DatabaseDef$class.withSession(DatabaseComponent.scala:34)
    at scala.slick.jdbc.JdbcBackend$DatabaseFactoryDef$$anon$4.withSession(JdbcBackend.scala:61)
    at scala.slick.backend.DatabaseComponent$DatabaseDef$class.withDynSession(DatabaseComponent.scala:51)
    at scala.slick.jdbc.JdbcBackend$DatabaseFactoryDef$$anon$4.withDynSession(JdbcBackend.scala:61)
    at com.snowplowanalytics.iglu.server.TableInitialization$.initializeTables(Core.scala:69)
    at com.snowplowanalytics.iglu.server.BootedCore$class.$init$(Core.scala:55)
    at com.snowplowanalytics.iglu.server.Boot$.<init>(Boot.scala:18)
    at com.snowplowanalytics.iglu.server.Boot$.<clinit>(Boot.scala)
    ... 1 more
Caused by: java.net.ConnectException: Connection refused
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.net.Socket.connect(Socket.java:579)
    at java.net.Socket.connect(Socket.java:528)
    at org.postgresql.core.PGStream.<init>(PGStream.java:60)
    at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:101)
    ... 42 more

[fblundun]

This happens because if you don't supply your own configuration file (and don't have the environment variables set by Elastic Beanstalk), this default gets used. So unless you have Postgres accessible on localhost:5432, the server will error.

[alexanderdean]

Hey @fblundun - is there a way of crashing rather than hanging? I ask because I think the hanging is making it very hard for Beanstalk to detect that the app is failing to start...