README

tape.module

About

• is extracted from Duct Core

• see this issue

• aims to support both Clojure & ClojureScript

This adds a layer of abstraction on top of Integrant. In Integrant, a configuration map is initiated into a running system map:

┌────────┐   ┌────────┐
│ config ├──>│ system │
└────────┘   └────────┘

In tape.module, the configuration is initiated twice. The configuration is first initiated into an intermediate configuration, which in turn is initiated into the system:

┌──────────────┐ init ┌────────────────┐ fold ┌─────────────┐ init ┌────────┐
│ modules-conf ├─────>│ modules-system ├─────>│ system-conf ├─────>│ system │
└──────────────┘      └────────────────┘      └─────────────┘      └────────┘

Keys in a tape.module configuration are expected to initiate into functions that transform a configuration map. There are two broad types: profiles, which merge their value into the configuration, and modules, which provide more complex manipulation.

Usage

Define a module:

my/module.cljs

(ns my.module
  (:require [integrant.code :as ig]
            [tape.module :as module]))

(defmethod ig/init-key ::module [_ _]
  (fn [config]
    (module/merge-configs config {:comp/one x, :comp/two y, ...})))

Use a module in a modules config map:

my/core.cljs

(ns my.core
  (:require [integrant.code :as ig]
            [tape.module :as module]))

(module/load-hierarchy)
(def config {:my.module/module nil, ... <other-modules>})
(def system (-> config module/prep-config ig/init))

A tape_hierarchy.edn file in the root of the src directory can be used to define derivations for modules keys. Always use (module/load-hierarchy) as a first form in your entry point to execute all the derivations.

License

Copyright © 2019 James Reeves, clyfe

Distributed under the MIT license.