Config parameters that have defaults should be optional

[hrj]

When a config parameter has a default value, the user should be able to optionally omit it from the config file.

For example, since playgroundEnabled has a default value of true, the user need not specify it.

Currently, the server throws an exception for missing parameters.

[rr83019]

Here's a list of config parameters, please choose the ones we want to make optional:

• port
• address
• throttle
• seed
• captchaExpiryLimit
• threadDelay
• playgroundEnabled
• corsHeader
• maxAttempts

[hrj]

Looks like all of them can be optional, and have sane defaults 😄

[rr83019]

Cool, any suggestion on what the defaults should be?

[hrj]

The defaults can be what is inside the automatically created config file:

{
  "randomSeed" : some random integer,
  "port" : 8888,
  "address" : "0.0.0.0",
  "captchaExpiryTimeLimit" : 5,
  "throttle" : 1000,
  "threadDelay" : 2,
  "playgroundEnabled" : true,
  "corsHeader" : "",
  "maxAttempts" : 10,
}

[rr83019]

Making the playgroundEnabled field string from bool.

The extract function of json4s is not able to convert JBool to java.lang.String

[hrj]

Ideally, we shouldn't change the type because it will break existing configurations.

I have added a suggestion to the PR, please have a look.