[jira] [Commented] (FLINK-1789) Allow adding of URLs to the usercode class loader

["Alexander Alexandrov (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-1789?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14390800#comment-14390800 ] 

Alexander Alexandrov commented on FLINK-1789:
---------------------------------------------

The problem with that approach is that the code loaded by the regular JVM class loader cannot refer to job specific types (which can be accessed only at the  UserCodeClassLoader level). Unfortunately, this is the case if we use the classpath entry to generate the dataflows dynamically at runtime.

My original "hack" was to therefore hardcode a filesystem path next to the list of jars when initializing the BlobManager, and I wanted to open an issue which makes this configurable when initializing the execution environment (this is basically the only main feature which prohibits the use of Emma with "off-the-shelf" Flink).

This, of course, would require that the folders are shared (e.g. via NFS) between client, master and workers. I think what made Stephan so excited is the idea of using the same URL mechanism in order to ship the code to all dependent parties (most probably by running a dedicated HTTP or FTP server on the client).

> Allow adding of URLs to the usercode class loader
> -------------------------------------------------
>
>                 Key: FLINK-1789
>                 URL: https://issues.apache.org/jira/browse/FLINK-1789
>             Project: Flink
>          Issue Type: Improvement
>          Components: Distributed Runtime
>            Reporter: Timo Walther
>            Assignee: Timo Walther
>            Priority: Minor
>
> Currently, there is no option to add customs classpath URLs to the FlinkUserCodeClassLoader. JARs always need to be shipped to the cluster even if they are already present on all nodes.
> It would be great if RemoteEnvironment also accepts valid classpaths URLs and forwards them to BlobLibraryCacheManager.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)