I'm calling the function getKeywords from another function and got an Unrecheable code detected section and don't understand why. Any help?
var env = require('dotenv').config();
var request = require('request')
var getKeywords = function(){
request.get('URI', //URI IS CORRECT IN MY CODE
function(err, httpResponse, body){
if(err){ //UNREACHABLE CODE DETECTED
console.error("request.post Error:", err);
return false;
} //UNREACHABLE CODE DETECTED
else{
console.log('Im here');
return JSON.parse(httpResponse.body).keywords;
}
});
}
module.export = getKeywords;
Here is the calling code.
var getKeywords = require('./getKeywords.js');
var keywords = new getKeywords();
var env = require('dotenv').config();
var difflib = require('difflib');
var postMention = require('./postMention.js');
var detection = function(obj, i){
var keyword = keywords[i];
var mentionObject = {
//some json
//postMention(mentionObject);
}
}
module.exports = detection;
Some tools have the ability to analyze every call to your function. It may be possible that all the places in your code that call the function you never set err parameter to true.
Related
I have this method :
// Parse a whole file
fs.readFile("klv-file.klv", (err, file) => {
var KLVdata = KLV.parseKLVfile(file, options);
var packets = KLVdata.packets;
var nDropped = KLVdata.nDropped;
});
in a small Node app.
How to I get the variable packets outside this object?
It's actually quite simple. Define the variables outside the function, and set them inside. Like this:
// Define variables
var packets = null;
var nDropped = null;
// Parse a whole file
fs.readFile("klv-file.klv", (err, file) => {
var KLVdata = KLV.parseKLVfile(file, options);
packets = KLVdata.packets;
nDropped = KLVdata.nDropped;
});
function doSomething(){
// you can now use the variables anywhere
}
Also: make sure to only use the variables if they have been defined.
// Define variables
var packets = null;
var nDropped = null;
// Parse a whole file
fs.readFile("klv-file.klv", (err, file) => {
var KLVdata = KLV.parseKLVfile(file, options);
packets = KLVdata.packets;
nDropped = KLVdata.nDropped;
packetsReady(); // your callback function
});
function packetsReady(){
// should only be called once the packets are ready
processPackets(packets);
}
Simply pass it to a function
let packets;
let nDropped;
function processKLV(KLVdata){
packets = KLVdata.packets;
nDropped = KLVdata.nDropped;
}
// Parse a whole file
fs.readFile("klv-file.klv", (err, file) => {
processKLV(KLV.parseKLVfile(file, options));
});
What am I doing wrong in the code below? The left_label and right_label variables seem to always be "true", when I know I have them in the Redis set to some string. I'm assuming it's because the client.get function is successful and returns true, but how do I get it to return the actual value?
var http = require('http');
var redis = require('redis');
var client = redis.createClient(6379, 127.0.0.1);
var server = http.createServer(function (request, response) {
var left_label = client.get('left', function(err, reply) {
console.log(reply);
return reply;
});
var right_label = client.get('right', function(err, reply) {
console.log(reply);
return reply;
});
response.writeHead(200, {"Content-Type": "text/html"});
var swig = require('swig');
var html = swig.renderFile('/var/www/nodejs/index.html', {
left: left_label,
right: right_label
});
response.end(html);
});
server.listen(8000);
console.log("Server running at http://127.0.0.1:8000/");
The get call is asynchronous and must be handled that way.
A suggestion would be to combine it with a promise library such as bluebird as suggested in the NPM documentation for the redis module.
That way, we can promisify the redis module and use it in a more simple way.
var redis = require('redis');
bluebird.promisifyAll(redis.RedisClient.prototype);
and use the new async version of the get function, as below.
function getLabelValues(){
var left_promise = client.getAsync("left").then(function(reply) {
return reply;
});
var right_promise = client.getAsync("right").then(function(reply) {
return reply;
});
return Promise.all([left_label, right_label]);
}
getLabelValues().then(function(results){
//This is run when the promises are resolved
//access the return data like below
var left_label = results[0];
var right_label = results[1];
});
fist of all im not shure if the following is a non-blocking problem?
im getting started with https://github.com/sahat/hackathon-starter
currently i try to read all files out of a folder and later process all files...
i used EventEmitter to kind of manage the workflow.
i want to clear all arrays if the URL is refeshed or loaded new, but somehow if i reaload the URL there seems to be something inside the arrays which cases multiple outputs of the same data?
at the moment i just would be happy to have a correct console.log output.
/**
* GET /
* Home page.
*/
var fs = require('fs');
//XML
var jsxml = require("node-jsxml");
var Namespace = jsxml.Namespace,
QName = jsxml.QName,
XML = jsxml.XML,
XMLList = jsxml.XMLList;
//EventEmitter
var EventEmitter=require('events').EventEmitter;
var dateinamenEE=new EventEmitter();
var dateiinhaltEE=new EventEmitter();
var dateinamen = [];
var dateiinhalt = [];
exports.index = function(req, res) {
fs.readdir('./data', function (err, files) {
if (!err) {
files.forEach(function(value) {
dateinamen.push(value);
});
dateinamenEE.emit('dateinamen_ready');
} else {
throw err;
}
});
dateinamenEE.on('dateinamen_ready',function(){
dateinamen.forEach(function(value) {
var buf = fs.readFileSync('./data/'+value, "utf8");
var xml = new XML(buf);
var list = xml.descendants("suggestion");
var ergebnis = "";
var basiswort = "";
var buchstabe = "";
var obj = null;
list.each(function(item, index){
ergebnis = item.attribute('data').toString()
//basiswort = value.replace("%2B", " ");
//basiswort = basiswort.replace(".xml", "");
//var pieces = buchstabe.split(" ");
obj = {k: basiswort, b: buchstabe, e: ergebnis};
dateiinhalt.push(obj);
});
});
dateiinhaltEE.emit('dateiinhalt_ready');
});
dateiinhaltEE.on('dateiinhalt_ready',function(){
//console.log(dateiinhalt);
console.log("dateinamen:" + dateinamen.length);
console.log("dateiinhalt:" + dateiinhalt.length);
});
res.render('home', {
title: 'Home'
});
};
If if log the length of the 2 arrays the output on the second reload shows. First time loading the url:
Express server listening on port 3000 in development mode
dateinamen:2
dateiinhalt:20
Second time / refreshing the url:
GET / 200 898.198 ms - -
GET /fonts/fontawesome-webfont.woff2?v=4.3.0 304 12.991 ms - -
GET /favicon.ico 200 4.516 ms - -
dateinamen:4
dateiinhalt:60
dateinamen:4
dateiinhalt:60
dateinamen:4
dateiinhalt:100
dateinamen:4
dateiinhalt:100
GET / 200 139.259 ms - -
What causes the code to extend the arrays while reloading the page?
The non-blocking problem is due do your for(...) loops.
Changing them by : array.forEach(function(elem, index){});
EDIT
The arrays should be initialized inside the index function :
exports.index = function(req, res) {
var dateinamen = [];
var dateiinhalt = [];
...
Also, I'm not sure you need the use of EventEmitter.
Something like
`
fs.readdir('./data', function (err, files) {
if (!err) {
files.forEach(function(file){
var buf = fs.readFileSync('./data/'+file, "utf8");
var xml = new XML(buf);
var list = xml.descendants("suggestion");
var ergebnis = null;
var obj = null;
list.each(function(item, index){
ergebnis = item.attribute('data').toString();
obj = {k: file, v: ergebnis};
dateiinhalt.push(obj);
});
});
console.log(dateiinhalt);
} else {
throw err;
}
});
`
could do the job no?
(I wanted to say this as a comment, but I'm still missing reputation)
My controller is a soap client as shown below
var _ = require('lodash'),
memoize = require('memoize'),
soap = require('soap'),
http = require('http');
var wsdlUrl = 'http://www.proxixnetwork.com/gsert/PxPointGeocode.asmx?WSDL';
var geocode = function(req,res){
var sessionId = null;
soap.createClient(wsdlUrl, function(err,client){
var args = {"username":'user123', "password":'password123'};
client.PxPointGeocode.PxPointGeocodeSoap.Authenticate(args,function(err,result){
res.jsonp(result.AuthenticateResult.SessionID);
})
});
}
exports.authenticate = geocode;
This soap service provides a session id that will be used in subsequent requests. Hence, I wanted to use 'memoize' to cache the method.
I defined a method that wraps around the soap call and 'memoize'ing it but the problem is that the call to soapClient is not happening.
I do not know how to make the call from router wait for the soap call
Note: Also tried async library's waterfall but did not work.
var _ = require('lodash'),
memoize = require('memoize'),
soap = require('soap'),
http = require('http'),
wsdlUrl = 'http://www.proxixnetwork.com/gsert/PxPointGeocode.asmx?WSDL';
var getSession = function () {
var args = {"username": 'user123', "password": 'password123'};
var sessionId = null;
soap.createClient(wsdlUrl, function (err, client) {
console.log('Inside proxix client'); //not printing
client.PxPointGeocode.PxPointGeocodeSoap.Authenticate(args, function (err, result) {
sessionId= result.AuthenticateResult.SessionID;
//if I use res.jsonp() - the call could be made
})
});
return sessionId;
};
var cached = memoize(getSession);
var geocode = function (req, res) {
var sesssionObj = cached();
res.jsonp(sessionObj);
}
exports.authenticate = geocode;
The two issues I'm seeing are :
memoize is a caching mechanism but is in no way going to change the ansynchronous nature of your function. Returning sessionId will not work because it is not set before it gets to that line. You need to use a callback.
You have not specified which arguments you want memoize to use for the caching, nor where you are getting those values. I'm going to assume for this example that it's username, password and wsdlUrl. and that they are set directly in req.
.
var _ = require('lodash'),
memoize = require('memoize'),
soap = require('soap'),
http = require('http');
var getSessionId = function(username,password,wsdlUrl,callback){
soap.createClient(wsdlUrl, function(err,client){
var args = {"username":username, "password":password};
client.PxPointGeocode.PxPointGeocodeSoap.Authenticate(args,function(err,result){
if(err){
return callback(err);
}
callback(null,result.AuthenticateResult.SessionID);
})
});
});
var getSessionIdCached = memoize(getSessionId,{async:true});
var geocode = function(req,res){
getSessionIdCached(req.username,req.password,req.wsdlUrl,function(err,sessionId){
if(err){
//do some error handling, and probably return
}
res.jsonp(sessionId);
});
});
exports.authenticate = geocode;
I have 3 node js files :
mysqlconnection.js to store the database connection properties:
var mysql = require('mysql');
var cjson = require('cjson');
var yaml_config = require('node-yaml-config');
// project files
var config = yaml_config.load(__dirname + '/billingv2.yaml');
exports.execute = function(callback){
var connection = mysql.createConnection(
{
host : config.host,
user : config.user,
password : config.password,
database : config.database,
}
);
connection.connect();
return callback(null,connection);
}
subscriptionRestService.js to handle the REST api calls:
var express = require('express');
var app = express();
app.use(express.bodyParser());
var fs = require('fs');
// Project files
var mysql = require('./mysqlRestService.js');
// Get Resource Subscription data by Resourceuri
app.post('/pricingdetails', function(req, res) {
var workload = req.body;
if(workload.elements && workload.elements.length > 0)
{
var arr = [];
for(var index in workload.elements)
{
arr[index] = workload.elements[index].uri;
}
var resourceIdentifiers = arr.join(',');
}
console.log(resourceIdentifiers);
mysql.getPricingDetail(function(resourceIdentifiers,callback){
});
});
mysqlRestService.js to handle mysql queries/stored procedures:
// packages
var mysql = require('mysql');
var cjson = require('cjson');
var fs = require('fs');
var yaml_config = require('node-yaml-config');
// project files
var dbconnection = require('./mysqlconnection');
exports.getPricingDetail = function (resourceIdentifiers,callback){
console.log('entered into mysql function');
console.log(resourceIdentifiers);
var pricingDetail = {};
dbconnection.execute(function(err,response){
if(err){
throw err;
}
else
{
var selectqueryString = "call SP_ExposePricingDetailforUI('" + resourceIdentifiers + "')";
response.query(selectqueryString, function(err,pricingDetail){
if(err) {
throw err;
}
else
{
console.log(pricingDetail);
pricingDetail = pricingDetail;
}
});
}
});
//console.log('printing pricing details');
//console.log(pricingDetail);
};
problems faced
Unable to send the variable resourceIdentifiers from subscriptionRestService to mysqlRestService.js
Unable to return the pricingdetail from mysqlRestService.js to calling function in subscriptionRestService.
Any guidance greatly appreciated.
Unable to send the variable resourceIdentifiers from subscriptionRestService to mysqlRestService.js
Well, you didn't send it. It currently is a parameter of your callback function in the invocation, not an argument for the parameter of getPricingDetails. Use
mysql.getPricingDetail(resourceIdentifiers, function callback(result){
// use result here
});
Unable to return the pricingdetail from mysqlRestService.js to calling function in subscriptionRestService.
I've got no idea what pricingDetail = pricingDetail; was supposed to do. You have to call (invoke) back the callback here! Use
callback(pricingDetail);