Client isn't connecting to server |
Always create output output stream before your input stream for Object
streams, otherwise you create a deadlock situation.
output = new ObjectOutputStream(socket.getOutputStream());
// output.flush(); if the underlying stream is buffered
input = new ObjectInputStream(socket.getInputStream());
The input reads the header written by the output, which won't be there
unless the output is created first.
|
Connecting to a remote machine through client-server |
You say the other machine has an external ip address. This implies it also
has a local ip address; ie it is behind a NAT firewall or similar. In this
case, you will have to configure the firewall to allow communication to
take place, eg by setting up port forwarding.
Applications such as MSN Messenger, VOIP clients etc have elaborate
mechanisms to negotiate this automatically, but they're often not very
successful.
|
Python - connecting sockets, client/server agnostic |
Here's a rather crude class that actually works to some extent, which might
get you started.
The main trick here is not to bother with listen at all: these are pure
peer to peer connections, fully specified by the <local-addr,
remote-addr> pair.
Note that the sockets are left in non-blocking mode. I caught the recv
exception but there can be a send one as well (plus, you get broken-pipe
errors when sending to a dead peer, etc). You'll also need to handle
EOF-from-terminated-peer (when recv returns '' instead of failing with
EAGAIN).
import errno
import os
import select
import socket
class Peer(object):
def __init__(self, local_addr, peer_addr):
self._local_addr = local_addr
self._peer_addr = peer_addr
self._renew()
self.reopen()
def _ren
|
Java client connecting to PHP server for MySQL database with authentication |
Create a PHP file that accepts POST.
In your JAVA, try passing a custom header KEY:VALUE pair that's verified
via your PHP file - or try to think of a more elaborate way.
Then, post along the username and password to the PHP file: POST
http://server.com/java-auth.php?user=username&pass=password for pseudo
example. Then, have that PHP file return a JSON-encoded string or a
serialized string... or go super fancy, and encrypt it all with
public/private keys.
Hope this helps :)
|
sqlsrv error while connecting to mssql server 2008 on windows 2003 server |
Two ways to try,
first to check if the Native driver has the right version -
is your server really a 32bit Version and not 84bit?
The other thing is, to check if the extensions are actually loaded.
To check that, create a file like "phpinfo.php" and put it in you folder
for .htdocs.
<?php
// show phpinfo file
phpinfo();
?>
The easy way is to search for it in the phpinfo-Page with Ctrl+F and
"extension=php_sqlsrv_53_ts_vc9.dll"
|
Getting an error when connecting from android to PHP server |
There are issues with your PHP. You are not passing back any JSON. You will
need to change your script to encode your array into JSON.
$result = json_encode($json)
Returning the actual JSON will help. Make sure you are not returning any
HTML either. Your Java is trying to parse a JSON response, but you are
responding with <!DOCTYPE...
|
Error connecting to server in a file |
This line:
inet_aton(h->h_addr_list[0],&indirizzo_server);
is wrong. h_addr_list is not a list of strings in the format that inet_aton
expects. It's not even a list of strings at all. It's a list of addresses
ready to be copied directly into the appropriate field of the struct
sockaddr_*.
The char **h_addr_list in struct hostent should be treated as void **,
which is what it would be if it hadn't been designed before ANSI C gave us
void. A generic pointer is used because gethostby* supports (at least
theoretically) arbitrary address families.
In the case of h_addrtype==AF_INET, each h_addr_list[n] is a pointer to a
struct in_addr, so you can just say indirizzo_server = *(struct in_addr
*)h_addr_list[0]; and all will be well.
|
Client-Server Program: Client can connect to server easily but server can't respond cause target machine actively refuses connections |
You need to design your client and server so that the client-to-server
connection remains open to recieve the responce and then do something like
this:
public static bool sendTo(IPEndPoint ip, String data)
{
TcpClient client = null;
NetworkStream stream = null;
StreamWriter writer = null;
StreamReader reader = null;
try
{
client = new TcpClient();
client.Connect(ip);
stream = c.GetStream();
writer = new StreamWriter(stream);
writer.WriteLine(data);
writer.Flush();
reader = new StreamReader(stream);
string response = reader.ReadLine();
if (response == "roger-alpha-tango")
{
return true;
}
}
catch
{
return false;
}
finally
{
i
|
"Illegal characters in path" error when connecting to SQL Server |
You'll need to escape argil3.mdf
Use \ or put an @ before the assignment of the string, for instance.
SqlConnection Con = new SqlConnection(@"Data
Source=.SQLEXPRESS;AttachDbFilename=|DataDirectory| argil3.mdf;Integrated
Security=True;Connect Timeout=30;User Instance=True");
|
secure auth error connecting to SQL server from RMySQL |
You may have an old my.cnf configuration on your local machine. You can
override the client option secure_auth in my.cnf or in a specific config
file you pass to dbConnect()
dbConnect(MySQL(), default.file="your-file.cnf"
The info on the setting is here:
https://dev.mysql.com/doc/refman/5.6/en/mysql-command-options.html#option_mysql_secure-auth
As an aside, you should really not be using 4.1-style password hashing :)
|
Database not found error when connecting to Derby network server |
By the JDBC url, it's looks like you're trying to connect to a Derby server
vs. an embedded instance. If you are trying to connect to a server
instance, here are some considerations:
did you start the server yourself, did mydb already exists?
if not, did you pass in the correct params to create (e.g. ;create=true)
example: jdbc:derby://localhost:1527/dbname;create=true
if mydb did exists, are you pointing the server to the correct location?
also, depending on what was used to start derby (e.g. embedded vs network
driver) default database locations are different as well. You can read
about it here
Basically the exception you're getting is that Derby's saying it can't find
your database - it's basically a path issue.
|
I'm trying to edit a datatable on a SQL server and i keep getting an error about either not accepting a keyword or not connecting due to a timeout |
The ConnectionString key in the connectionString section of your web.config
is used for an SqlClient.SqlConnection but you specify to use
providerName="System.Data.OleDb". You should change to
providerName="System.Data.SqlClient" The OleDb client cannot understand
that syntax.
Then the UPDATE command uses 5 parameters, but you add only one to the
Parameters collection. This will be another error, after the opening of the
connection.
Then in BindGridView you use a connectionstring not defined anywhere,
finally the SELECT statement here refers to a table named GridView, I
suspect that you have mistyped the correct name of the table (the one used
in the update command is called DevTesting )
For the timeout problem you should add the exception message connected to
the timeout
|
netcat client doesn't exit with error when tcp server has error |
TCP doesn't have any concept of the remote server "crashing". When a
program with an open TCP socket ends (regardless of how), the OS will close
the socket.
In order to do what you want, you would need to create a protocol where the
server would acknowledge completion of whatever operation you want it to
perform and then the client would exit with failure unless it got that
application-layer acknowledgement.
|
Error consuming Web Service: SOAP-ENV:Client Internal Server Error SoapDoc::CheckNameSpace: Wrong xml name space |
After hours of investigation, i solved it, the problem was the Soap
version, by default, Zend uses Soap 1.2.
When i changed it to the 1.1 version, everything works perfectly.
$params = array(
'soapVersion' => SOAP_1_1
);
$client = new Zend_Soap_Client($url, $params);
I hope help somebody with this :D
Greetings
|
C# :Does Client machine need SQL Server installed on it while connecting to other machine having SQL Server installed on it (the Server machine) |
The pieces needed to connect to SQL server are built into the .net
framework. As long as you used those when coding the client piece you can
connect to a SQL Database without MSSQL installed on the client.
using System.Data;
using System.Data.SqlClient;
SqlClient
PS: I am asking beforehand to avoid the last minute hassle on the day of
installation.
You should always test locally first. You can probally get your hands on a
random test machine to verify that everything is good to go.
|
Client - Server program: send string from client to server and received respond |
As the server, just write back into the very same NetworkStream you read
the string from! On the client side - nothing different - read freom the
NetworkStream you just wrote the string to.
Your NetworkStream objects should simply work in both directions ;)
|
server error sent to client in express |
You already have the answer in your question. You need error-handling
middleware (app.use a function with an arity of 4) to handle the error.
You just need to add the error-handling middleware after the router. Your
example puts the the error handler above the the router.
Either move the app.use(function (err, req, res, next)) to the bottom of
your code or insert
app.use(app.router);
above the error handler.
Refer to the documentation for more information about error handlers.
|
What should a RESTful client do with its POST, PUT, or DELETE request upon a server error (500) |
4xx errors are "something is wrong with the client, they're sending the
wrong stuff".
5xx errors are "something is wrong with the server, sorry it's out sick
today."
Which basically means there's nothing the client can imply from a 5xx
error. It could be permanent, it could be transient, the client doesn't
know.
IIS sends a 500 error because IT doesn't know what happened. If your app is
blindly throwing exceptions up to the web tier, there's not much more it
can do or say about it.
If the server logic somehow actually KNOWS what's wrong, and WHEN it might
be fixed, it can send a 503 error, telling the client it's unavailable and
a Retry-After header telling the client when it will be back.
As for a client behavior, it's sort of dependent on the clients history
with the service. Maybe
|
How to test if an error occurred on the Server, and output client side |
I have this simple solution for you...
if(req.getParameter("report").equals("true"))
{
req.getSession().setAttrinute("REPORT_OK",false);
//If the query string parameter is set, generate the PDF.
if(!PdfReportGenerator.generateReport(res, repositoryURI)) {
// Something went wrong, so redirect the browser.
res.sendRedirect(req.getRequestURI());
}else{
req.getSession().setAttrinute("REPORT_OK",true);
}
}
Now in your RequestURI page have a document.ready() function to check with
ajax about the state of the REPORT_OK variable.
Case 1: If the value is null that means that the request in not a callback
from your code above, so you don't display anything to the user.
Case 2: If the value is false, then that means than an error happened and
you can inform the user about i
|
Client-Server communication in REST, Spring (RestTemplate): getting 404 error |
I guess you are using the wrong url to call the Web Service
http://localhost:8081/SpringMVCMerchant/movieTheater.htm
This ends with .htm whereas your RequestMapping does not contains this
request pattern
Update:
Make sure there no console errors and also, if your server application is
running on 8081.
|
XAMPP Apache error: client denied by server configuration |
Apache in Xampp will not start if there is another application using port
80.
For example : Skype uses port 80. Therefore when Skype is running Apache
will refuse to start since its working port is not available to be
registered.
You have mentioned that you tried to access the server from your parents
website. How did you do that? Xampp do not allow non local ip's to access
its apache server running on local machine / network.
If you want this behavior to be changed, use "Allow All" and remove if any
"Deny" parameter is specified in httpd.conf.
Don't forget to save config file. Restart the Apache server to apply the
new rule.
Cheers..!!
|
Error 401 Google-api-php-client verifing by server Android inapppurchase |
I think my problem was because I was trying to use Service Accounts with a
Google Apps Gmail own account ( non @gmail.com account ).
I had to delegate domain-wide authority to my service account.
And I had to instantiate a Android Publisher Service as follows: ( only
founded in Google Api Drive documentation ).
I added "sub" parameter programmatically in Google_AssertionCredentials
like follows:
$auth = new Google_AssertionCredentials(
SERVICE_ACCOUNT_NAME,
'https://www.googleapis.com/auth/androidpublisher',
$key);
$auth->sub = "myown@email.com";
$client->setAssertionCredentials($auth);
The documentation in Google Play Android Developer API is very poor, and
Google Support doesn't help, they redirects you to documentation. Google
PHP developers even don't know how Service Accounts
|
Passing server error message to client (using Express and Backbone) |
Found a solution. Define a class variable and capture the return from the
fetch call:
private xhr: XMLHttpRequest = null;
Then:
public fetchObject(successF: Function, failF: Function): void {
this.myObj = new MyObj();
this.xhr = this.myObj.fetch({ success: successF, error: failF });
}
Finally:
private failF(model, xhr, options): void {
doSomething(this.xhr.responseText);
}
this.xhr will contain the reponseText (i.e. 'CUSTOM ERROR MESSAGE'). The
local xhr will still be a blank string.
I'm still not sure why this is the case, and if anyone has some insight I'd
appreciate it.
|
"Unhandled Error" comes when TCP server tries to accept connections from client in twisted |
class ChatServer(Protocol):
def connectionMade(self):
print("A Client Has Connected")
factory = Factory()
reactor.listenTCP(80,factory)
You haven't made any association between factory and ChatServer in this
code. Try inserting this line:
factory.protocol = ChatServer
In an upcoming (not yet released) version of Twisted, Factory is getting a
new class method to make this set-up even easier. Using that version, this
example would be even shorter:
class ChatServer(Protocol):
def connectionMade(self):
print("A Client Has Connected")
reactor.listenTCP(80, Factory.forProtocol(ChatServer))
|
Connecting datapower and worklight client side |
You cannot make arbitrary requests outside of your domain from the client
side using AJAX. See for example:
Origin is not allowed by Access-Control-Allow-Origin
|
Connecting to a Web Service using Client Certificate authentication |
It appears that the server did not understand TLS.
I had to specify SSLv3, via
System.Net.ServicePointManager.SecurityProtocol =
System.Net.SecurityProtocolType.Ssl3;
|
Connecting to HDP 2.0 (Hortonworks Hadoop) with yarn client |
Current version of Hortonworks HDP 2.0 VM only works with libs taken from
VM itself. Here is the description of what needs to be done:
http://fusionworks.md/connecting-to-yarn-on-hortonworks-hdp-2-0/
|
HTTP 500 Internal Server Error when executing client javascript in any XPage |
Thanks everybody for your help. Naveen's advice proved very useful. After
checking "Display XPage runtime error" on Designer (Application ->
Properties -> Tab XPages), the error message was much more meaningful:
The generated page version 8.5 is not compatible with the
server version 3.0, for the page /prueba.xsp.
The problem is that my Notes Client and Designer are a higher (8.5.3)
version than the Domino Server (8.5). According to this note:
http://www-10.lotus.com/ldd/ddwiki.nsf/dx/XPagesPageVersions.htm, the
eventHandler syntax has been changed slightly, and this causes the XPage to
be marked as version 8.5.1. This also explains why it works when the
database is local!
I have tried the workaround suggested in the note (altering in the page
source back the event handler
|
The SMTP server requires a secure connection or the client was not authenticated - Error |
I solved this problem by passing email with email user name in the
following in the format
User Name< example@domain.com >
Sample from Amazon site is already working for me,
here is my working code,
AWSCredentials objAWSCredentials = new BasicAWSCredentials(AWSAccessKey,
AWSSecretKey);
Destination destination = new Destination().WithToAddresses(new
List<string>() { TO });
// Create the subject and body of the message.
Content subject = new Content().WithData(SUBJECT);
Content textBody = new Content().WithData(BODY);
Body body = new Body().WithHtml(textBody);
//Body body = new Body().WithText(textBody);
// Create a message with the specified subject and body.
Message message = new Message().WithSubject(subject).WithBody(body);
// Assemble the email.
SendEmailRequ
|
Batch File Connecting to Server and execute program install on connected server |
Here's a little code to help you connect to the SQL server and interrogate
the SQL version.
@ECHO OFF
SQLCMD /? > nul 2> nul
IF ERRORLEVEL 1 ECHO.SQLCMD not found on this machine & PAUSE &
GOTO :eof
SET SQLCmdLine=SQLCMD -b -w400
REM use something like the next line for NT authentication; second line for
SQL authentication
REM for NT SET SQLCmdLine=%SQLCmdLine% -E -S "YourServerName"
REM for SA SET SQLCmdLine=%SQLCmdLine% -U "YourSQLUserName" -P
"YourSQLPassword" -S "YourServerName"
SET Database=YourDatabaseName
REM I will use NT Authentication for this example
SET SQLCmdLine=%SQLCmdLine% -E -S "(local)"
SET TestSQLCmdLine=%SQLCmdLine% -h-1 -d "%Database%"
REM this will get the SQL version
%TestSQLCmdLine% -Q "SELECT @@VERSION" | FINDSTR /v "rows affected"
REM this will
|
BCP IN error : [Microsoft][SQL Server Native Client 10.0]Unexpected EOF encountered in BCP data-file |
Oh, BTW, i was getting frustrated with the same issue today. Turns out the
format file had a prefix length specifier that had a value of 2 (auto
prompted during format file generation - why?) for field two which was a
varchar field. Once I made it to field length specifier to 0, file started
working.
PS: my file was tab separated.
|
Hive Server 2 thrift Client error: Required field 'operationHandle' is unset |
Are you really sure you set the operationsHandle field to a valid value?
The Thrift eror indicates what it says: The API expects a certain field
(operationHandle in your case) to be set, which has not been assigned a
value. And you stack trace confirms this:
Struct:TFetchResultsReq(operationHandle:null, orientation:FETCH_FIRST,
maxRows:1)
|
Client A change source mac address to Client B when send packet, But Client B's module can not rx packet after server sent |
Probably because your switch has seen client B's MAC address on the port to
client A and has remembered that. It will therefore send the reply on the
ethernet port to client A, not to client B's erhernet port.
This seems to be a networking issue, not a programming issue. Therefore
this question might be more appropriate on a different forum.
|
iOS Client connecting to NodeJS socket.io results in Stream end encountered |
Turns out that socket.io has its own authentication protocol and is not
compatible with SocketRocket out of the box. See this SO answer:
How to use SocketRocket with socket.io?
From the answers there, you could take a look at socket.io-objc
|
Google Play Game Services client setup and connecting |
All set! Finally after some tries without result, here is the method
(suitable for libgdx users).
Answer to the First Question: There's no need at all to get requests or
even use the AuthUtil class provided by google.
Answer to the Second Question:
Make sure to read some tutorials about GamesClient and its implementation.
Step1: Get the BaseGameUtils library provided by Google, here.
Step2: implement GameHelper.GameHelperListenner on your MainActivity, for
example:
public class MainActivity extends AndroidApplication implements
GameHelper.GameHelperListener
and declare a GameHelper that will do all the sign in work for you. (dont
forget to call its constructor and setup method, see GameHelper class for
more information).
Step3: call beginUserInitiatedSignIn() (from the GameHelpe
|
Camelot Error: The client was not authorised by the server. Ensure that the ConnectionString property on the Connection is correct |
This usually means that the
credentials in the connectionstring is wrong, or
connection wasn’t allowed from the client
the authentication didn’t succeed from a client that is on a different
domain
Credential management
It is important that the parameters in the connectionstring are correct, if
you have used authentication=default you may try using the
authentication=ntlm instead and remember to check and recheck that your
user have access rights to the specified SharePoint Server and Site
Allowing connections
There is something called “loopback errors” that occurs internally in
Windows. There are a lot of articles on how to work with this; we prefer
the simple approach to solve this by using PowerShell
Execute the following PowerShell command on each SharePoint frontend ser
|
send image from server to client and from client to server |
read() on a socket stream will return -1 only if connection is closed or an
error occurs. Server receives the data and saves it but never leaves the
receiver loop to send data. Even if it would do the client wouldn't then
leave its receiver loop either.
You must either close the connection or send file size before the actual
file and receiving stops when given size was read.
|
Client/Server Application That Can Deploy Client From Server |
I have built an application which does exactly what you require, and the
solution is fairly straitforward if not necessarily easy.
Firstly, the client runs a specialised client proxy (seperate assembly
running as it's own process)with a thin fixed interface and the server runs
a specialised server proxy with a thin fixed interface.
On client init', the client passes assembly and configuration (file and
registry, etc.) version info in a composite value object through the Client
proxy. Server checks info' and if required returns a url for a packaged
archive if an update is required. The client proxy downloads the archive
(which consists of a script, assemblies, resources and config), shut's down
the main client, executes the script which contains installation
instructions, and then restart
|
Node.js terminates execution before script is finished, connecting via socket.io-client |
I'd start by seeing if socket.io is throwing any errors:
socket.on('error', function (exception) {
console.log(exception);
});
I'd also look to see if you're connecting to the right port. It's probable
that the remote socket.io server is not on a default port.
|
ZeroMQ, Client<-> Server , bi-directional communication possible with only having the client connect to host? |
For connecting to the server, you need a DEALER socket on the client side,
and a ROUTER socket on the server. Because you need a publish subscribe
pattern you will need a SUB socket on the client side, and a PUB socket on
the server side.
Client Server
+-------+ +--------+
| Dealer| <--> | Router |
| Sub | <-- | Pub |
+-------+ +--------+
So you bind the Router and the Pub sockets, and connect the Dealer, and the
Sub sockets. Than when you want to:
Publish Messages (no reply expected): Create an envelope ( pub, channel,
message ) and send it through the Dealer, on the Router side the router
will receive the following envelope ( dealer, pub, channel, message ), so
you can publish the message on channel through PUB socket.
Receive Messages (no reply exp
|