darc-mongoreadyserverconfig v0.1.4

Introduction

Package to handle flexible configuration for the darc-mongoreadyserver package. Our intention is that it should be easy to run a server, from the command line, based on this package.

You can specify environment variables, either with export or with a .env file in your project's root directory. All environment variables should be preceeded by your project name, in upper case, with any - characters replaced with _, followed by an _, and then the variable name. For example,

MYPROJECT_CUSTOM_ENV_VAR="Hi!"

This will be read into the configuration object with the key custom-env-var. Of course, the variables can also be the defaults required by the package, as in

MYPROJECT_PORT=6000
MYPROJECT_SSL_CERT=/path/to/sssl/cert
MYPROJECT_SSL_KEY=/path/to/ssl/key

You can specify a configuration file, currently in JSON form. You can set an environment variable MYPROJECT_CONFFILE to point to this file, or you can use the command line argument '--conffile'. Such a configuration file will be read and imported into the configuration directly.

You can also run with long-form command line arguments (run with --help to see which), and you can even specify your own command line arguments (and value checks). Our examples here show how to use command line arguments; to add custom arguments you need to pass arguments optargs and/or checks to the routine returned from the require call:

require( 'darc-monngoreadyserver' )( modules , optargs , checks )
	...

optargs should be an object whose keys are the long-form options to include (minus the -- prefix), and whose corresponding values should be argparse-ready option setting objects. For example,

let optargs = {
	'custom-flag' : { help : 'An extra flag' , action : "storeTrue" , default : false } , 
	'custom-arg' : { help : 'An extra argument' , default : 7 } , 
}

See the argparse docs for more details. checks, if provided, should be an object whose keys are the argument names (e.g., custom-flag) and whose values are strings that can be executed as an eval statement over a single variable val returning a boolean. For example,

let checks = { 
	'custom-arg' : 'val >= 2'
}

These different routes have a specific precedence order: environment variables are overwritten by config file values which are overwritten by command line arguments (to the degree there are any conflicts). The only exception is a config file path itself, which is set to any value from the environment overwritten by any command line argument provided.