configure-local.tests.ts

import CHAI                 = require('chai')
const  expect               = CHAI.expect



describe('configure-local', function() {

    process.env.NODE_ENV = 'development'
    var configure = require('configure-local')

    function scopeEnvVars(env: {}, test: () => void) {
        var saved = process.env
        process.env = env
        test()
        process.env = saved
    }


    function scopeArgs(args: string[], test: () => void) {
        var saved = process.argv
        process.argv = args.concat(args)
        test()
        process.argv = saved
    }


    describe('settings and overrides', function() {

        describe('using config files only', function() {

            it('should respect setting specified only in config/common.json', function() {
                expect(configure.get('external_service:api_key')).to.equal('0a1b2c3d')
            })


            it('should respect setting specified only in config/development.json', function() {
                expect(configure.get('PORT')).to.equal(1001)
            })


            it('should override setting in config/common.json with one from config/development.json', function() {
                expect(configure.get('external_service:url')).to.equal('https://external_service.co/api/v2/')
            })

        })


        describe('using environment variables', function() {

            it('should override a setting in config/common.json', function() {
                scopeEnvVars({NODE_ENV: 'development', 'external_service:api_key': 'key_for_testing'}, () => {
                    configure.test.reset()
                    expect(configure.get('external_service:api_key')).to.equal('key_for_testing')
                })
            })


            it('should override a setting in config/development.json', function() {
                scopeEnvVars({NODE_ENV: 'development', PORT: '3333'}, () => {
                    configure.test.reset()
                    expect(configure.get('PORT')).to.equal('3333')
                })
            })

        })


        describe('using command line arguments', function() {

            it('should override a setting in config/development.json', function() {
                scopeArgs(['--PORT', '8888'], function() {
                    configure.test.reset()
                    expect(configure.get('PORT')).to.equal(8888)
                })
            })


            it('should override a setting in environment variables', function() {
                scopeEnvVars({NODE_ENV: 'development', PORT: '3333'}, () => {
                    scopeArgs(['--PORT', '8888'], function() {
                        configure.test.reset()
                        expect(configure.get('PORT')).to.equal(8888)
                    })
                })
            })

        })


        describe('using defaults', function() {

            it('should return default when not overridden', function() {
                expect(configure.get('CONFIG_DIR')).to.equal('config')
            })


            it('should be overridden by environment variable', function(done) {
                process.env.CONFIG_DIR = '/var/config'
                try {
                    // test.reset() throws an error because the config file doesnt exist
                    configure.test.reset()
                } catch (error) {
                    expect(error.message).to.equal("ENOENT: no such file or directory, access '/var/config/development.json'")
                    done()
                }
                var env = process.env
                delete env['CONFIG_DIR']
            })

        })


    })


    describe('Configuration selection by instance environment name', function() {

        it('should throw an error if NODE_ENV is unset', function() {
            var saved = process.env.NODE_ENV
            process.env.NODE_ENV = undefined
            expect(configure.test.reset).to.throw(Error)
            process.env.NODE_ENV = saved
        })


        it('should throw an error if NODE_ENV doesnt match a config file', function() {
            var saved = process.env.NODE_ENV
            process.env.NODE_ENV = 'devel'
            expect(configure.test.reset).to.throw(Error)
            process.env.NODE_ENV = saved
        })


        it('should select production when NODE_ENV=production', function() {
            scopeEnvVars({NODE_ENV: 'production'}, () => {
                configure.test.reset()
                expect(configure.get('PORT')).to.equal(2002)
            })
        })


    })

})