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node-red/nodes/core/core/80-template.js
2018-07-14 00:11:59 +09:00

183 lines
6.5 KiB
JavaScript

/**
* Copyright JS Foundation and other contributors, http://js.foundation
*
* 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.
**/
module.exports = function(RED) {
"use strict";
var mustache = require("mustache");
var yaml = require("js-yaml");
function parseContext(key) {
var match = /^(flow|global)(\[(\w+)\])?\.(.+)/.exec(key);
if (match) {
var parts = {};
parts.type = match[1];
parts.store = (match[3] === '') ? "default" : match[3];
parts.field = match[4];
return parts;
}
return undefined;
}
/**
* Custom Mustache Context capable to collect message property and node
* flow and global context
*/
function NodeContext(msg, nodeContext, parent, escapeStrings, promises, results) {
this.msgContext = new mustache.Context(msg,parent);
this.nodeContext = nodeContext;
this.escapeStrings = escapeStrings;
this.promises = promises;
this.results = results;
}
NodeContext.prototype = new mustache.Context();
NodeContext.prototype.lookup = function (name) {
var results = this.results;
if (results) {
var val = results.shift();
return val;
}
// try message first:
try {
var value = this.msgContext.lookup(name);
if (value !== undefined) {
if (this.escapeStrings && typeof value === "string") {
value = value.replace(/\\/g, "\\\\");
value = value.replace(/\n/g, "\\n");
value = value.replace(/\t/g, "\\t");
value = value.replace(/\r/g, "\\r");
value = value.replace(/\f/g, "\\f");
value = value.replace(/[\b]/g, "\\b");
}
this.promises.push(Promise.resolve(value));
return value;
}
// try flow/global context:
var context = parseContext(name);
if (context) {
var type = context.type;
var store = context.store;
var field = context.field;
var target = this.nodeContext[type];
if (target) {
var promise = new Promise((resolve, reject) => {
var callback = (err, val) => {
if (err) {
reject(err);
} else {
resolve(val);
}
};
target.get(field, store, callback);
});
this.promises.push(promise);
return '';
}
else {
this.promises.push(Promise.resolve(''));
return '';
}
}
else {
this.promises.push(Promise.resolve(''));
return '';
}
}
catch(err) {
throw err;
}
}
NodeContext.prototype.push = function push (view) {
return new NodeContext(view, this.nodeContext, this.msgContext, undefined, this.promises, this.results);
};
function TemplateNode(n) {
RED.nodes.createNode(this,n);
this.name = n.name;
this.field = n.field || "payload";
this.template = n.template;
this.syntax = n.syntax || "mustache";
this.fieldType = n.fieldType || "msg";
this.outputFormat = n.output || "str";
var node = this;
node.on("input", function(msg) {
function output(value) {
/* istanbul ignore else */
if (node.outputFormat === "json") {
value = JSON.parse(value);
}
/* istanbul ignore else */
if (node.outputFormat === "yaml") {
value = yaml.load(value);
}
if (node.fieldType === 'msg') {
RED.util.setMessageProperty(msg, node.field, value);
node.send(msg);
} else if ((node.fieldType === 'flow') ||
(node.fieldType === 'global')) {
var context = RED.util.parseContextStore(node.field);
var target = node.context()[node.fieldType];
target.set(context.key, value, context.store, function (err) {
if (err) {
node.error(err, msg);
} else {
node.send(msg);
}
});
}
}
try {
/***
* Allow template contents to be defined externally
* through inbound msg.template IFF node.template empty
*/
var template = node.template;
if (msg.hasOwnProperty("template")) {
if (template == "" || template === null) {
template = msg.template;
}
}
if (node.syntax === "mustache") {
var is_json = (node.outputFormat === "json");
var promises = [];
mustache.render(template, new NodeContext(msg, node.context(), null, is_json, promises, null));
Promise.all(promises).then(function (values) {
var value = mustache.render(template, new NodeContext(msg, node.context(), null, is_json, null, values));
output(value);
}).catch(function (err) {
node.error(err.message);
});
} else {
output(template);
}
}
catch(err) {
node.error(err.message);
}
});
}
RED.nodes.registerType("template",TemplateNode);
RED.library.register("templates");
}