dgbuilder/red/nodes/index.js

/**
 * Copyright 2013, 2014 IBM Corp.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/
var registry = require("./registry");
var credentials = require("./credentials");
var flows = require("./flows");
var Node = require("./Node");

/**
 * Registers a node constructor
 * @param type - the string type name
 * @param constructor - the constructor function for this node type
 * @param opts - optional additional options for the node
 */
function registerType(type,constructor,opts) {
    if (opts && opts.credentials) {
        credentials.register(type,opts.credentials);
    }
    registry.registerType(type,constructor);    
}

/**
 * Called from a Node's constructor function, invokes the super-class
 * constructor and attaches any credentials to the node.
 * @param node the node object being created
 * @param def the instance definition for the node 
 */
function createNode(node,def) {
    Node.call(node,def);
    var creds = credentials.get(node.id);
    if (creds) {
        node.credentials = creds;
    }
}

function init(_settings,storage) {
    credentials.init(storage);
    flows.init(storage);
    registry.init(_settings);
}

function checkTypeInUse(id) {
    var nodeInfo = registry.getNodeInfo(id);
    if (!nodeInfo) {
        throw new Error("Unrecognised id: "+info);
    }
    var inUse = {};
    flows.each(function(n) {
        inUse[n.type] = (inUse[n.type]||0)+1;
    });
    var nodesInUse = [];
    nodeInfo.types.forEach(function(t) {
        if (inUse[t]) {
            nodesInUse.push(t);
        }
    });
    if (nodesInUse.length > 0) {
        var msg = nodesInUse.join(", ");
        throw new Error("Type in use: "+msg);
    }
}

function removeNode(id) {
    checkTypeInUse(id);
    return registry.removeNode(id);
}

function removeModule(module) {
    var info = registry.getNodeModuleInfo(module);
    for (var i=0;i<info.nodes.length;i++) {
        checkTypeInUse(info.nodes[i]);
    }
    return registry.removeModule(module);
}


function disableNode(id) {
    checkTypeInUse(id);
    return registry.disableNode(id);
}

module.exports = {
    // Lifecycle
    init: init,
    load: registry.load,
    
    // Node registry
    createNode: createNode,
    getNode: flows.get,
    
    addNode: registry.addNode,
    removeNode: removeNode,
    
    addModule: registry.addModule,
    removeModule: removeModule,
    
    enableNode: registry.enableNode,
    disableNode: disableNode,
    
    // Node type registry
    registerType: registerType,
    getType: registry.get,
    getNodeInfo: registry.getNodeInfo,
    getNodeModuleInfo: registry.getNodeModuleInfo,
    getNodeList: registry.getNodeList,
    getNodeConfigs: registry.getNodeConfigs,
    getNodeConfig: registry.getNodeConfig,
    clearRegistry: registry.clear,
    cleanNodeList: registry.cleanNodeList,
    
    // Flow handling
    loadFlows: flows.load,
    stopFlows: flows.stopFlows,
    setFlows: flows.setFlows,
    getFlows: flows.getFlows,
    
    // Credentials
    addCredentials: credentials.add,
    getCredentials: credentials.get,
    deleteCredentials: credentials.delete
}