f3lang/cdi

/**
 * The dependency tree keeps track of module dependencies.
 * You can see a dependency tree as some kind of dimension.
 * Multiple instances of one module can exist concurrently in
 * different trees. If you don't explicitly define the tree,
 * a module should reside in, it will also be instantiated in
 * the tree of the parent module.
 *
 * @author Wolfgang Felbermeier (@f3lang)
 */
class DependencyTree {

    /**
     * @param {ObjectManager} objectManager
     * @param {ModuleResolver} moduleResolver
     * @param {String} identifier The identifier of this tree
     */
    constructor(objectManager, moduleResolver, identifier) {
        this.identifier = identifier;
        this.objectManager = objectManager;
        this.moduleResolver = moduleResolver;
    }

    /**
     * Returns an instance of the current tree
     * @param {string} moduleName The name of the module
     * @param {string} requestId The unique request id to detect circular dependencies
     */
    getInstance(moduleName, requestId) {
        let moduleMeta = this.moduleResolver.getResolvedModules().moduleMap[moduleName];
        if(!moduleMeta) {
            throw new Error('[cdi] Module with identifier "' + moduleName + '" not found');
        }
        let scope = moduleMeta.config.scope;
        let instantiator = this.objectManager.getInstantiator(scope);
        return instantiator.getInstance(moduleMeta.path, moduleMeta.config, this.identifier, requestId);
    }

}

module.exports = DependencyTree;
module.exports.inject = ['ObjectManager', 'ModuleResolver'];