Configuration¶

Your Fathom application is configured by a HOCON resource file named conf/default.conf.

Profiles¶

Your application may have several configuration profiles. Each profile must have a corresponding configuration file. The default configuration profile specifies the conf/default.conf resource configuration file.

You may choose your profile by specifying the --profile launch argument.

java -jar myapp.jar --profile myProfile

This example will load the conf/myProfile.conf resource configuration file.

Modes¶

A mode is used to change the behavior of your application and the settings loaded from the profile configuration file.

There are three available modes:

Name	Description
PROD	Mode for production deployment
TEST	Mode for unit/integration tests
DEV	Mode for development or debugging

The runtime mode can be specified at launch time:

java -jar myapp.jar --mode DEV

Modes & Settings¶

The profile configuration file supports mode-specific settings.

For example, consider the following configuration:

mail {
  server = smtp.gmail.com
  port = 465
}

dev.mail {
  port = 1465
}
test.mail.port = 2465

In this example, the port 1564 will be used when the application is run in the DEV mode, port 2465 when the application is run in the TEST mode, and port 465 for all other modes.

Overriding Settings¶

Fathom will first load your profile configuration from the conf resource directory of your classpath.

If there is a same-named configuration file in the java.home directory (usually the directory from which your application was launched), this file will be parsed & merged with the classpath-sourced configuration.

This allows you to deploy a complete configuration profile built-into your application and then discretely override individual settings for that profile on an as-needed basis.

Settings¶

# Application metadata and settings
application {
  name = "My Application"
  version = "1.0.0"
  # The advertised application url for rendered pages, sent emails, etc
  url = "https://app.domain.com"
}

# Undertow server settings
undertow {

  # Setting a port to 0 disables that transport
  httpPort = 8080
  httpsPort = 0
  ajpPort = 0

  # Define the network interface for HTTP serving
  # e.g. 0.0.0.0 will serve on all available network interfaces
  httpListenAddress = "0.0.0.0"

  # Define the network interface for HTTPS serving
  # e.g. 0.0.0.0 will serve on all available network interfaces
  httpsListenAddress = "0.0.0.0"

  # Define the network interface for AJP serving
  # e.g. 0.0.0.0 will serve on all available network interfaces
  ajpListenAddress = "0.0.0.0"

  # The context path of your application.
  # This is useful if you are running your application behind a reverse proxy
  # and you have to create proxy/rewrite rules.
  contextPath = "/"

  # Optionally setup https/SSL
  keystoreFile = ""
  keystorePassword = ""
  truststoreFile = ""
  truststorePassword = ""

  # Threads
  #
  # io threads accept incoming socket connections
  # worker threads handle your logic post-socket-accept

  # Specify the number of io threads for handling socket requests.
  # A value of 0 will use Undertow's default which is:
  #  - 2 io threads for a single-core machine
  #  - 1 io thread/core for a multi-core machine
  ioThreads = 0

  # Specify the number of worker threads for handling your logic.
  # A value of 0 will use Undertow's default which is:
  #  - 8*ioThreads
  workerThreads = 0

  # Buffers
  #
  # Undertow adaptively sizes it's buffers based on the heap allocated to the JVM.
  #
  # If the heap < 64M:
  #  - bufferSize = 512
  #  - buffersPerRegion = 10
  #    this allocates 10*512 bytes
  #
  # If the heap < 128M:
  #  - bufferSize = 1K
  #  - buffersPerRegion = 10
  #    this allocates 10*1k
  #
  # Else
  #  - bufferSize = 16k
  #  - buffersPerRegion = 20
  #    this allocates 20*16k

  # Set the buffer size.
  # A value of 0 uses Undertow's adaptive default.
  #  e.g. 16k, 32k
  bufferSize = 16k

  # Set the number of buffers.
  # A value of 0 uses Undertow's adaptive default.
  buffersPerRegion = 20

}