0.18

• The deprecated parse, validate, inputs and highlight functionality from the command line tool has been removed in favor of wdltool (https://github.com/broadinstitute/wdltool)
• Workflow options can now include a defaultRuntimeOptions section, so that the same runtime attribute is not needed in every single WDL task. E.g.:

{
  "defaultRuntimeOptions": {
    "docker": "ubuntu:latest"
  }
}

• Changed the JES runtime attributes defaultDisks and defaultZones to be simply disks and zones respectively.
• Liquibase scripts now run automatically. Non-persistent, in-memory databases are not affected. However Cromwell will
  not start if it detects evidence of manually run liquibase migrations in a persistent database. Instead, before Cromwell
  will start cleanly, the database should backed up, and then this SQL should be manually executed:

update DATABASECHANGELOG
  set MD5SUM = null,
    FILENAME = substr(FILENAME, instr(FILENAME, "src/main/migrations/") + length("src/main/migrations/"))
  where FILENAME like '%src/main/migrations/%'

• Added Preemptible VMs support for JES. This has impacts on the API Endpoint responses as a Call/Shard can now be attempted multiple times. Each attempt will have its own entry.
• Added custom thread pool to workaround Slick deadlocks. The thread pool
  size defaults to the Slick configuration value db.numThreads, but may be increased up to Slick's
  db.maxConnections, via a new property actionThreadPoolSize.
• Added support for size WDL standard library function.
• Allow for runtime attribute values to be interpreted as full expressions. For example:

task example {
  String ubuntu_tag
  command { ... }
  runtime {
    docker: "ubuntu:" + ubuntu_tag
  }
}

• Add runtime attributes in Call metadata :

{
  "workflowName": "hello",
  "calls": {
    "hello.hello": [
      {
        ...,
        "runtimeAttributes": {
                  "preemptible": "0",
                  "failOnStderr": "false",
                  "disks": "local-disk 10 SSD",
                  "continueOnReturnCode": "0",
                  "docker": "ubuntu:latest",
                  "cpu": "1",
                  "zones": "us-central1-a",
                  "memory": "2GB"
                },
        ...
      }
    ]
  }
}

• Added "preemptible" field in Call metadata. This only appears if the backend is JES.

{
  "workflowName": "hello",
  "calls": {
    "hello.hello": [
      {
        ...,
        "preemptible": "true"
        ...
      }
    ]
  }
}