How to use VCAP_APP_PORT - port

how do you get cloudfoundry to assign a port? I am adding applications and I'd like to have a different port for each but VCAP_APP_PORT is not set. VCAP_APP_HOST is set but VCAP_APP_PORT is not.

Take a look at http://show-env.cloudfoundry.com/
It's a node application I knocked together just to output the environment and the request headers when you call it, the code looks like this;
var http = require('http');
var util = require('util');
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.write(util.inspect(process.env));
res.write("\n\n************\n\n");
res.end(util.inspect(req.headers));
}).listen(3000);
You can see the VCAP_APP_PORT in the output;
It would be handy to know which framework you are using, however, all these variables should be stored in the system environment so it shouldn't really matter.

Cloud Foundry will automatically assign each application instance an IP address and port and these values are accessible in the VCAP_* variable as Dan describes. You don't get to tell Cloud Foundry which port you prefer. Each instance of your app may receive a different IP address and port, so you should always interrogate the environment to find out what they are if you need that information.

Related

what is MQTT url to my thingsboard instance

I have a thingsboard UI available at "thingsboard.MYDOMAIN.io:8080". I'm using NodeJS and MQTT.js. I can connect using the sample code on that page. But I don't know what URL i would use in that connect string. I've tried using that URL and putting MQTT:// on the front of it to no avail.
It's just one device coming into a thingsboard. I wouldn't think i would need to add anything other than the default thingsboard.
If someone could tell what the expect default URL would be?
The default MQTT port number is 1883 so something like
mqtt://thingsboard.mydomain.io:1883
would be a good starting point. You should even be able to leave the port number off e.g.
mqtt://thingsboard.mydomain.io
Connection code should be something like this:
var mqtt = require('mqtt');
const thingsboardHost = "127.0.0.1";
const ACCESS_TOKEN = "**********";
// Initialization of mqtt client using Thingsboard host and device access token
console.log('Connecting to: %s using access token: %s', thingsboardHost, ACCESS_TOKEN);
var client = mqtt.connect('mqtt://'+ thingsboardHost, { username: ACCESS_TOKEN });
The default MQTT port number is 1883, but you don't have to manually set that value. Take a look at the source code.
https://github.com/mqttjs/MQTT.js

Is passing environment variables to sapper's client side secure with Rollup Replace?

I am using replace in my rollup configuration for sapper and sapper-environment to pass environment variables to the client side in sapper - is this secure? Is there a better/safer way to approach this?
Using this config below:
rollup.config.js
const sapperEnv = require('sapper-environment');
export default {
client: {
input: config.client.input(),
output: config.client.output(),
plugins: [
replace({
...sapperEnv(),
'process.browser': true,
'process.env.NODE_ENV': JSON.stringify(mode)
})
...
And then this allows me to use the variables in stores.js:
import { writable } from 'svelte/store';
import Client from 'shopify-buy';
const key = process.env.SAPPER_APP_SHOPIFY_KEY;
const domain = process.env.SAPPER_APP_SHOPIFY_DOMAIN;
// Initialize a client
const client = Client.buildClient({
domain: domain,
storefrontAccessToken: key
});
export { key, domain, client };
I have tried running this in server,js and passing the variables through the session data, but client side no matter what I do they always seems to return 'undefined'.
There are two questions here — a) is it secure, and b) why are the values undefined?
The answer to the first question is 'no'. Any time you include credentials in JavaScript that gets served to the client (or in session data), you're making those credentials available to anyone who knows how to look for them. If you need to avoid that, you'll need your server (or another server) to make requests on behalf of authenticated clients.
As for the second part, it's very hard to tell without a reproduction unfortunately!

Proxy for OAuthUtil.GetAccessToken

I've setup a perfectly functioning application (in VB) that allows user to access his Google Sheets.
The application follows Google's OAuth documentation for displaying a sign-in dialog in a web browser, obtains user's permission and access codes, uses access codes to obtain access token, and then uses the Google Sheet's Query service to get hold of Google Sheets. Very simple. Works fine.
Problem occurs on computers that have internet proxy defined on them. In the rest of my application and most of Google Sheets API, I can define a manual internet proxy. GData's RequestFactory allows manually configuring proxy server. The only line of code that doesn't support (to my current knowledge) is the OAuthUtil library used for obtaining access token. It doesn't allow defining internet proxy server, hence it is unable to resolve host on computers behind proxy environment. Following is my pseudo code:
Dim parameters As New OAuth2Parameters
parameters.ClientId = CLIENT_ID
parameters.ClientSecret = CLIENT_SECRET
parameters.RedirectUri = REDIRECT_URI
parameters.Scope = SCOPE
>>Show browser window and obtain access code
parameters.AccessCode = login.Token
OAuthUtil.GetAccessToken(parameters) '<< Point of failure
Dim requestFactory As GOAuth2RequestFactory = New GOAuth2RequestFactory(Nothing, My.Application.Info.ProductName, parameters)
requestFactory.Proxy = GetProxySettings() '<< my code for defining proxy
myService = New SpreadsheetsService("Application")
myService.RequestFactory = requestFactory
Another important aspect is that my application works on Mac OSX as well using Wine (for web browser I use GeckoFX). If internet proxy is globally defined on the environment then the OAuthUtil works fine, but this doesn't work for Wine. I have tried setting internet proxy in the command-line environment, or in the registry and refreshed system settings, still the applications running in Wine do not understand that proxy is defined. Hence proxy has to be manually defined.
I need help to figure out a solution by any of the following:
* A way to forcefully/manually define proxy for OAuthUtil for obtaining access token
* Any other way to obtain OAuth access token if proxy cannot be defined as above (maybe WebClient can be used?)
* Some way to define global internet proxy in Wine so applications like GData API read and understand the proxy setting. Though I'd rather prefer manually defined proxy at application level.
Any ideas folks?
Regards
F.A.
I've figured it out. Turns out that the 'OAuthUtil.GetAccessToken' only uses system-defined proxy. There is no way to manually define internet proxy, like RequestFactory supports. So there is a work-around using WebClient:
Try
'// Get access token from code
Using WC As New WebClient
' Define proxy
WC.Proxy = GetProxySettings()
' Set parameters
WC.Headers(HttpRequestHeader.ContentType) = "application/x-www-form-urlencoded"
' Get response
Dim postURL = "https://www.googleapis.com/oauth2/v4/token"
Dim postParams = "code=" & parameters.AccessCode &
"&client_id=" & Uri.EscapeDataString(CLIENT_ID) &
"&client_secret=" & Uri.EscapeDataString(CLIENT_SECRET) &
"&redirect_uri=" & Uri.EscapeDataString(REDIRECT_URI) &
"&grant_type=authorization_code"
Dim responsebody As String = WC.UploadString(postURL, postParams)
' Read response
Dim jObj As JObject = JsonConvert.DeserializeObject(responsebody)
' Store token
parameters.AccessToken = jObj("access_token").ToString
parameters.RefreshToken = jObj("refresh_token").ToString
parameters.TokenType = jObj("token_type").ToString
parameters.TokenExpiry = Now().AddSeconds(CDbl(jObj("expires_in").ToString))
End Using
Catch ex As Exception
MsgBox("Error obtaining access token: " & ex.Message, MsgBoxStyle.Critical)
Return Nothing
End Try

MBeanServerConnection.invoke hangs forever

We have an app that invokes various remote methods on MBeans using MBeanServerConnection.invoke.
Occasionally one of these methods hangs.
Is there any way to have a timeout on the call? so that it will return with an exception if the call takes too long?
Or do I have to move all those calls into separate threads so they don't lock up the UI and require killing the app?
See http://weblogs.java.net/blog/emcmanus/archive/2007/05/making_a_jmx_co.html
===== Update =====
I was thinking about this stuff when I first responded, but I was on my mobile and I can't type worth a damn on it.....
This is really an RMI problem, and unless you use a different protocol, there's not much you can do, except, as you say, move all those calls into separate threads so they don't lock up the UI.
But.... if you have the option of fiddling with the target server and you can customize the connecting client, you have at least 1 option which is to customize the JMXConnectorServer on your target servers.
The standard JMXConnectorServer implementation is the RMIConnectorServer. Part of it's specification is that when you create a new instance using any of the constructors (like RMIConnectorServer(JMXServiceURL url, Map environment)), the environment map can contain a key/value pair where the key is RMIConnectorServer.RMI_CLIENT_SOCKET_FACTORY_ATTRIBUTE and the value is a RMIClientSocketFactory. Therefore, you can specify a socket factory method like this:
RMIClientSocketFactory clientSocketFatory = new RMIClientSocketFactory() {
public Socket createSocket(String host, int port) {
Socket s = new Socket(host, port);
s.setSoTimeout(3000);
}
};
This factory creates a Socket and then sets its SO_TIMEOUT using setSoTimeout, so when the client connects using this socket, all operations, including connecting, will timeout after 3000 ms.
You could also checkout the JMXMP connector and server in the jmx-optional package of the OpenDMK. (links are to my github mavenized). No built in solution, mind you, but they're super easy to extend and JMXMP is simple TCP socket based rather than RMI, so this type of customization would be trivial.
Cheers.
# Nicholas : The above code is not working.I mean request is not getting timeout after 3000. ms.
map.put(RMIConnectorServer.RMI_CLIENT_SOCKET_FACTORY_ATTRIBUTE , new RMIClientSocketFactory() {
#Override
public Socket createSocket(String host, int port) throws IOException {
if(logger.isInfoEnabled() ){
logger.info("JMXManager inside createSocket..." + host + ": port :" + port);
}
Socket s = new Socket(host, port);
s.setSoTimeout(3000);
return s;
}
});
cs = JMXConnectorServerFactory.newJMXConnectorServer(url,map,mbeanServer);
As I answered on: How to set request timeout for JMX Connector the RMI properties can help you. All the properties are on Oracle documentation site:
http://docs.oracle.com/javase/7/docs/technotes/guides/rmi/sunrmiproperties.html.
For example: -Dsun.rmi.transport.tcp.responseTimeout=60000 is a client side tcp response timeout. There are also properties for connect timeout and for server side connections.
I also am not happy how the JMX/RMI/TCP stack hides important settings from lower level protocols, and makes it not available for a single connection.

Twitter oAuth callbackUrl - localhost development

Is anyone else having a difficult time getting Twitters oAuth's callback URL to hit their localhost development environment.
Apparently it has been disabled recently. http://code.google.com/p/twitter-api/issues/detail?id=534#c1
Does anyone have a workaround. I don't really want to stop my development
Alternative 1.
Set up your .hosts (Windows) or etc/hosts file to point a live domain to your localhost IP. such as:
127.0.0.1 xyz.example
where xyz.example is your real domain.
Alternative 2.
Also, the article gives the tip to alternatively use a URL shortener service. Shorten your local URL and provide the result as callback.
Alternative 3.
Furthermore, it seems that it works to provide for example http://127.0.0.1:8080 as callback to Twitter, instead of http://localhost:8080.
I just had to do this last week. Apparently localhost doesn't work but 127.0.0.1 does Go figure.
This of course assumes that you are registering two apps with Twitter, one for your live www.mysite.example and another for 127.0.0.1.
Just put http://127.0.0.1:xxxx/ as the callback URL, where xxxx is the port for your framework
Yes, it was disabled because of the recent security issue that was found in OAuth. The only solution for now is to create two OAuth applications - one for production and one for development. In the development application you set your localhost callback URL instead of the live one.
Callback URL edited
http://localhost:8585/logintwitter.aspx
Convert to
http://127.0.0.1:8585/logintwitter.aspx
This is how i did it:
Registered Callback URL:
http://127.0.0.1/Callback.aspx
OAuthTokenResponse authorizationTokens =
OAuthUtility.GetRequestToken(ConfigSettings.getConsumerKey(),
ConfigSettings.getConsumerSecret(),
"http://127.0.0.1:1066/Twitter/Callback.aspx");
ConfigSettings:
public static class ConfigSettings
{
public static String getConsumerKey()
{
return System.Configuration.ConfigurationManager.AppSettings["ConsumerKey"].ToString();
}
public static String getConsumerSecret()
{
return System.Configuration.ConfigurationManager.AppSettings["ConsumerSecret"].ToString();
}
}
Web.config:
<appSettings>
<add key="ConsumerKey" value="xxxxxxxxxxxxxxxxxxxx"/>
<add key="ConsumerSecret" value="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"/>
</appSettings>
Make sure you set the property 'use dynamic ports' of you project to 'false' and enter a static port number instead. (I used 1066).
I hope this helps!
Use http://smackaho.st
What it does is a simple DNS association to 127.0.0.1 which allows you to bypass the filters on localhost or 127.0.0.1 :
smackaho.st. 28800 IN A 127.0.0.1
So if you click on the link, it will display you what you have on your local webserver (and if you don't have one, you'll get a 404). You can of course set it to any page/port you want :
http://smackaho.st:54878/twitter/callback
I was working with Twitter callback url on my localhost. If you are not sure how to create a virtual host ( this is important ) use Ampps. He is really cool and easy. In a few steps you have your own virtual host and then every url will work on it. For example:
download and install ampps
Add new domain. ( here you can set for example twitter.local) that means your virtual host will be http://twitter.local and it will work after step 3.
I am working on Win so go under to your host file -> C:\Windows\System32\Drivers\etc\hosts and add line: 127.0.0.1 twitter.local
Restart your Ampps and you can use your callback. You can specify any url, even if you are using some framework MVC or you have htaccess url rewrite.
Hope This Help!
Cheers.
Seems nowadays http://127.0.0.1 also stopped working.
A simple solution is to use http://localtest.me instead of http://localhost it is always pointing to 127.0.0.1 And you can even add any arbitrary subdomain to it, and it will still point to 127.0.0.1
See Website
When I develop locally, I always set up a locally hosted dev name that reflects the project I'm working on. I set this up in xampp through xampp\apache\conf\extra\httpd-vhosts.conf and then also in \Windows\System32\drivers\etc\hosts.
So if I am setting up a local dev site for example.com, I would set it up as example.dev in those two files.
Short Answer: Once this is set up properly, you can simply treat this url (http://example.dev) as if it were live (rather than local) as you set up your Twitter Application.
A similar answer was given here: https://dev.twitter.com/discussions/5749
Direct Quote (emphasis added):
You can provide any valid URL with a domain name we recognize on the
application details page. OAuth 1.0a requires you to send a
oauth_callback value on the request token step of the flow and we'll
accept a dynamic locahost-based callback on that step.
This worked like a charm for me. Hope this helps.
It can be done very conveniently with Fiddler:
Open menu Tools > HOSTS...
Insert a line like 127.0.0.1 your-production-domain.com, make sure that "Enable remapping of requests..." is checked. Don't forget to press Save.
If access to your real production server is needed, simply exit Fiddler or disable remapping.
Starting Fiddler again will turn on remapping (if it is checked).
A pleasant bonus is that you can specify a custom port, like this:
127.0.0.1:3000 your-production-domain.com (it would be impossible to achieve this via the hosts file). Also, instead of IP you can use any domain name (e.g., localhost).
This way, it is possible (but not necessary) to register your Twitter app only once (provided that you don't mind using the same keys for local development and production).
edit this function on TwitterAPIExchange.php at line #180
public function performRequest($return = true)
{
if (!is_bool($return))
{
throw new Exception('performRequest parameter must be true or false');
}
$header = array($this->buildAuthorizationHeader($this->oauth), 'Expect:');
$getfield = $this->getGetfield();
$postfields = $this->getPostfields();
$options = array(
CURLOPT_HTTPHEADER => $header,
CURLOPT_HEADER => false,
CURLOPT_URL => $this->url,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_SSL_VERIFYPEER => false,
CURLOPT_SSL_VERIFYHOST => false
);
if (!is_null($postfields))
{
$options[CURLOPT_POSTFIELDS] = $postfields;
}
else
{
if ($getfield !== '')
{
$options[CURLOPT_URL] .= $getfield;
}
}
$feed = curl_init();
curl_setopt_array($feed, $options);
$json = curl_exec($feed);
curl_close($feed);
if ($return) { return $json; }
}
I had the same challenge and I was not able to give localhost as a valid callback URL. So I created a simple domain to help us developers out:
https://tolocalhost.com
It will redirect any path to your localhost domain and port you need. Hope it can be of use to other developers.
set callbackurl in twitter app : 127.0.0.1:3000
and set WEBrick to bind on 127.0.0.1 instead of 0.0.0.0
command : rails s -b 127.0.0.1
Looks like Twitter now allows localhost alongside whatever you have in the Callback URL settings, so long as there is a value there.
I struggled with this and followed a dozen solutions, in the end all I had to do to work with any ssl apis on local host was:
Go download: cacert.pem file
In php.ini * un-comment and change:
curl.cainfo = "c:/wamp/bin/php/php5.5.12/cacert.pem"
You can find where your php.ini file is on your machine by running php --ini in your CLI
I placed my cacert.pem in the same directory as php.ini for ease.
These are the steps that worked for me to get Facebook working with a local application on my laptop:
goto apps.twitter.com
enter the name, app description and your site URL
Note: for localhost:8000, use 127.0.0.1:8000 since the former will not work
enter the callback URL matching your callback URL defined in TWITTER_REDIRECT_URI your application
Note: eg: http://127.0.0.1/login/twitter/callback (localhost will not work).
Important enter both the "privacy policy" and "terms of use" URLs if you wish to request the user's email address
check the agree to terms checkbox
click [Create Your Twitter Application]
switch to the [Keys and Access Tokens] tab at the top
copy the "Consumer Key (API Key)" and "Consumer Secret (API Secret)" to TWITTER_KEY and TWITTER_SECRET in your application
click the "Permissions" tab and set appropriately to "read only", "read and write" or "read, write and direct message" (use the least intrusive option needed for your application, for just and OAuth login "read only" is sufficient
Under "Additional Permissions" check the "request email addresses from users" checkbox if you wish for the user's email address to be returned to the OAuth login data (in most cases check yes)

Resources