The overwrite of the header origin is caused by `Allow-Control-Allow-Origin: *` chrome extension.

[Link to the extension][1]

Try disabling this extension in order to solve your problem.


  [1]: https://chrome.google.com/webstore/detail/allow-control-allow-origi/nlfbmbojpeacfghkpbjhddihlkkiljbi

To create a jupyter_notebook_config.py file if it is not there, , you can use the following command line from ~/.jupyter:

    $ jupyter notebook --generate-config
Uncomment this 

    c.NotebookApp.allow_origin = &#39;*&#39;



I am trying to set an Image for bar button Item for that I have an image like:

![enter image description here][1]

with resolution 30 * 30 but while I assign this Image to Bar button Its looks like:

![enter image description here][2]

I have assigned image this way :

![enter image description here][3]

and If I try this way like making an IBOutlet for the button and set Image programatically form [this][4] question and code for that is:

     // Outlet for bar button
     @IBOutlet weak var fbButton: UIBarButtonItem!

    // Set Image for bar button
    var backImg: UIImage = UIImage(named: &quot;fb.png&quot;)!
    fbButton.setBackgroundImage(backImg, forState: .Normal, barMetrics: .Default)

but nothing happend with this,

Can anybody tell me what I am doing wrong?

or which is the batter way to do this?


  [1]: http://i.stack.imgur.com/WDODD.png
  [2]: http://i.stack.imgur.com/0UAHf.png
  [3]: http://i.stack.imgur.com/omDWS.png
  [4]: https://stackoverflow.com/questions/24769770/swift-setting-back-button-image-in-nav-bar

How to set image for bar button with swift?

I have a dataframe (df) and want to print the unique values from each column in the dataframe.

I need to substitute the variable (i) [column name] into the print statement

    column_list = df.columns.values.tolist()
    for column_name in column_list:
        print(df.&quot;[column_name]&quot;.unique()

**Update**

When I use this: I get **&quot;Unexpected EOF Parsing&quot;** with no extra details.

    column_list = sorted_data.columns.values.tolist()
    for column_name in column_list:
          print(sorted_data[column_name].unique()

What is the difference between your syntax YS-L (above) and the below:

    for column_name in sorted_data:
          print(column_name)
          s = sorted_data[column_name].unique()
          for i in s:
            print(str(i))

print the unique values in every column in a pandas dataframe

I&#160;am trying to send form data to a webservice but below &quot;Request Header&quot; in the &quot;Network&quot; of the Chrome DOM&#160;I got the origin &quot;evil.com&quot; and referer &quot;localhost:8080&quot;. 

    Accept:application/json, text/plain, */*
    Accept-Encoding:gzip, deflate
    Accept-Language:nb-NO,nb;q=0.8,no;q=0.6,nn;q=0.4,en-US;q=0.2,en;q=0.2
    Connection:keep-alive
    Content-Length:91
    Content-Type:application/x-www-form-urlencoded; charset=UTF-8;
    Host:office.insoft.net:9091
    Origin:http://evil.com/
    Referer:http://localhost:8080/
    User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2230.0 Safari/537.36

I&#160;want to change to another origin and &quot;localhost:8080&quot; would be the best origin.

How do I&#160;resolve that problem?


Origin evil.com in Request Header

I am trying to send form data to a webservice but below "Request Header" in the "Network" of the Chrome DOM I got the origin "evil.com" and referer "localhost:8080".
<pre><code class="hljs language-makefile">Accept:application/json, text/plain, */*
Accept-Encoding:gzip, deflate
Accept-Language:nb-NO,nb;q=0.8,no;q=0.6,nn;q=0.4,en-US;q=0.2,en;q=0.2
Connection:keep-alive
Content-Length:91
Content-Type:application/x-www-form-urlencoded; charset=UTF-8;
Host:office.insoft.net:9091
Origin:http://evil.com/
Referer:http://localhost:8080/
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2230.0 Safari/537.36
</code></pre>
I want to change to another origin and "localhost:8080" would be the best origin.
How do I resolve that problem?

I am using ReSTful webservice. I am uploading multiple photos with one function (PHP).

I have used `$num_files = count($_FILES[&#39;myfile&#39;][&#39;name&#39;])` to count number of files that are to be uploaded but this always gives 1:

![Image][1]

When I print `$_FILES[&#39;myfile&#39;][&#39;name&#39;]` or `$_FILES` it returns last image.

Am I suppose to do any setting to send multiple files at a time?

[1]: http://i.stack.imgur.com/EsQ9G.png

    &lt;?php
    if($result==&quot;success&quot;)
    {
     	$num_files = count($_FILES[&#39;myfile&#39;][&#39;name&#39;]);
    	Zend_Debug::dump($num_files);
    	die;
    	for( $i=0; $i &lt; $num_files; $i++ )
    	{
    		$name = $_FILES[&quot;myfile&quot;][&quot;name&quot;][$i];
    		$temp_path = $_FILES[&#39;myfile&#39;][&#39;tmp_name&#39;][$i];
    		$image_name = Helper_common::getUniqueNameForFile( $name );
    	  	
    		echo $image_name;
    		die;
    		// Set the upload folder path
    		$target_path = $originalDirecory.&quot;/&quot;;
    	  
    	  
    		// Set upload image path
    		$image_upload_path = $target_path.$image_name;
    		move_uploaded_file($temp_path, $image_upload_path);
    		
    		//if(move_uploaded_file($temp_path, $image_upload_path))
    		//{
    		// Set 800*800 popup thumbnail...
    		// Set popup directory...
    		$thumbnail_directory=$popUpDirectory.&quot;/&quot;;
    		// Set thumbnail name...
    		$thumb_name1=$thumbnail_directory.&#39;thumbnail_&#39;.$image_name;
    		// Set width and height of the thumbnail...
    		$thumb_width=800;
    		$thumb_height=800;
    		$thumb1=Helper_common::generateThumbnail($image_upload_path, $thumb_name1, $thumb_width, $thumb_height);
    	
    		//if($thumb)
    		//{
    			// Set 435*333 thumbnail...
    			// Set thumbnail directory...
    			$thumbnail_directory=$wallDirecory.&quot;/&quot;;
    			// Set thumbnail name...
    			$thumb_name2=$thumbnail_directory.&#39;thumbnail_&#39;.$image_name;
    			// Set width and height of the thumbnail...
    			$thumb_width=435;
    			$thumb_height=435;
    			$thumb2=Helper_common::generateThumbnail($image_upload_path, $thumb_name2, $thumb_width, $thumb_height);
    			 
    			//if($thumb)
    			//{
    				// Set 176*176 thumbnail...
    				// Set thumbnail directory...
    				$thumbnail_directory=$galleryDirectory.&quot;/&quot;;
    				// Set thumbnail name...
    				$thumb_name3=$thumbnail_directory.&#39;thumbnail_&#39;.$image_name;
    				// Set width and height of the thumbnail...
    				$thumb_width=176;
    				$thumb_height=176;
    				$thumb_smart_resize_3 = Helper_ImageResizer::smart_resize_image($image_upload_path, NULL, $thumb_width, $thumb_height, false, $thumb_name3, false);
    				$thumb3=Helper_common::generateThumbnail($image_upload_path, $thumb_name3, $thumb_width, $thumb_height);
    			//if($thumb)
    			//{
    				$profile_thumb=$thumb3;
    				// Set 131*131 thumbnail...
    				// Set thumbnail directory....
    				$thumbnail_directory = $thumbnailsDirectory.&quot;/&quot;;
    				// Set thumbnail name....
    				$thumb_name4 = $thumbnail_directory.&#39;thumbnail_&#39;.$image_name;
    				$thumb_width=131;
    				$thumb_height=131;
    				$thumb_smart_resize_4=Helper_ImageResizer::smart_resize_image($image_upload_path, NULL, $thumb_width, $thumb_height, false, $thumb_name4, false);
    				$thumb4=Helper_common::generateThumbnail($image_upload_path, $thumb_name4, $thumb_width, $thumb_height);
    	
    				}


How to send multiple files in postman ReSTful web service?

I am studying how to Spring handle REST web services (but I don&#39;t know if it is a Spring related answer or more generically it is related only to REST concept).

So my doubt is: what exactly is the HTTP status return code for a successful DELETE statement?

Is it the **204** or the **200**?

I know that the **200** means that my request was correctly fulfilled but reading online it seems to me that it I expect it **after a successful GET returning content** and not after a delete.

Somewhere I found that the **204** status is obtained **after
successful PUT or DELETE**. Is it true? I can&#39;t understand, it means that **the response is empty**, why an empty respons means that the PUT or the DELETE operation are gone succesfull?

What is the HTTP status return code for a successful DELETE statement in REST?

I am using [WS websocket][1] library of node.js. Currently I&#39;m running ws server. Now I want to secure this connection by using secure connections i.e by implementing wss protocol and also library support TLS connection. I searched a little and found this  [plain to secure: wss][2] and this [wss with self signed certificate][3] .

Both are not very detailed and the article on the second link describes wss with self signed certificate. What i want to know is if it is enough to just create the self signed certificate and deploy to my production environment or do I need to buy a certificate as we need to do while creating HTTPS servers?


  [1]: https://github.com/websockets/ws
  [2]: http://www.giacomovacca.com/2015/02/websockets-over-nodejs-from-plain-to.html
  [3]: http://www.chovy.com/web-development/self-signed-certs-with-secure-websockets-in-node-js/

How to Create Secure(TLS/SSL) Websocket Server

I am writing a server for an iOS game. The game is turn-based and the only time the server needs to push information to the client is to notify of the opponent&#39;s move.

I am curious if anyone could comment on the performance and ease of implementation differences between using WebSockets and long polling. Also, if I used WebSockets, should I only use it to receive information and send POST requests for everything else, or should all communication be through the WebSocket?

Additionally, is there anything extra to consider between WebSockets and long polling if I am interested in also making a web client?


Differences between websockets and long polling for turn based game server

I am trying to understand in which scenario I should pick a service registry over a load balancer.

From my understanding both solutions are covering the same functionality.

For instance if we consider **consul.io** as a feature list we have:

 - Service Discovery
 - Health Checking
 - Key/Value Store
 - Multi Datacenter

Where a load balancer like **Amazon ELB** for instance has:

 - configurable to accept traffic only from your load balancer
 - accept traffic using the following protocols: HTTP, HTTPS (secure HTTP), TCP, and SSL (secure TCP)
 - distribute requests to EC2 instances in multiple Availability Zones
 - The number of connections scales with the number of concurrent requests that the load balancer receives
 - configure the health checks that Elastic Load Balancing uses to monitor the health of the EC2 instances registered with the load balancer so that it can send requests only to the healthy instances
 - You can use end-to-end traffic encryption on those networks that use secure (HTTPS/SSL) connections
 - [EC2-VPC] You can create an Internet-facing load balancer, which takes requests from clients over the Internet and routes them to your EC2 instances, or an internal-facing load balancer, which takes requests from clients in your VPC and routes them to EC2 instances in your private subnets. Load balancers in EC2-Classic are always Internet-facing.
 - [EC2-Classic] Load balancers for EC2-Classic support both IPv4 and IPv6 addresses. Load balancers for a VPC do not support IPv6 addresses.
 - You can monitor your load balancer using CloudWatch metrics, access logs, and AWS CloudTrail.
 - You can associate your Internet-facing load balancer with your domain name. 
 - etc.

So in this scenario I am failing to understand why I would pick something like `consul.io` or `netflix eureka` over `Amazon ELB` for service discovery.


I have a hunch that this might be due to implementing **client side service discovery** vs **server side service discovery**, but I am not quite sure.

Service discovery vs load balancing

For a project of mine (see [BigPictu.re][1] or [bigpicture.js GitHub project][2]), I have to deal with potentially a very, very, very big `&lt;div&gt;` container.

I knew there was a risk of poor performance with the simple approach I use, but I did not expect it to be mostly present with ... Chrome only!

If you test [this small page][3] (see code below), panning (click + drag) will be:

* Normal / smooth on Firefox
* Normal / smooth even on Internet Explorer
* Very slow (nearly crashing) on Chrome!

Of course, I could add some code (in my project) to do that when you&#39;re zoomed in a lot, text with potentially very very big font-size would be hidden. But still, **why does Firefox and Internet&amp;nbsp;Explorer handle it correctly and not Chrome?**

**Is there a way in JavaScript, HTML, or CSS to tell the browser *not to try* to render the whole page (which is 10000 pixels wide here) for every action?** (only render the current viewport!)

____

    &lt;!DOCTYPE html&gt;
    &lt;html lang=&quot;en&quot;&gt;
        &lt;head&gt;
            &lt;meta charset=&quot;utf-8&quot;&gt;
            &lt;style&gt;
                html, body {
                    overflow: hidden;
                    min-height: 100%; }

                #container {
                    position: absolute;
                    min-height: 100%;
                    min-width: 100%; }

                .text {
                    font-family: &quot;Arial&quot;;
                    position: absolute;
                }
            &lt;/style&gt;
        &lt;/head&gt;

        &lt;body&gt;
            &lt;div id=&quot;container&quot;&gt;
                &lt;div class=&quot;text&quot; style=&quot;font-size: 600px; left:100px; top:100px&quot;&gt;Small text&lt;/div&gt;
                &lt;div class=&quot;text&quot; style=&quot;font-size: 600000px; left:10000px; top:10000px&quot;&gt;Very big text&lt;/div&gt;
            &lt;/div&gt;

            &lt;script&gt;
                var container = document.getElementById(&#39;container&#39;), dragging = false, previousmouse;
                container.x = 0; container.y = 0;

                window.onmousedown = function(e) { dragging = true; previousmouse = {x: e.pageX, y: e.pageY}; }

                window.onmouseup = function() { dragging = false; }

                window.ondragstart = function(e) { e.preventDefault(); }

                window.onmousemove = function(e) {
                    if (dragging) {
                        container.x += e.pageX - previousmouse.x; container.y += e.pageY - previousmouse.y;
                        container.style.left = container.x + &#39;px&#39;; container.style.top = container.y + &#39;px&#39;;
                        previousmouse = {x: e.pageX, y: e.pageY};
                    }
                }
            &lt;/script&gt;
        &lt;/body&gt;
    &lt;/html&gt;

  [1]: http://bigpictu.re/demo
  [2]: http://github.com/josephernest/bigpicture.js/
  [3]: http://gget.it/caveot4g/big-div-test.html


A very, very, very big div

It&#39;s doing my eyes in!

looks fine in IE and Firefox

![enter image description here][1]


Chrome(Above)

Running version 39 of chrome,
only appears blurry in a modal box, does not make any difference if I change the font family.

This is the CSS (for label &quot;Start&quot;) the browser renders the following

    box-sizing: border-box;
    color: rgb(85, 85, 85);
    cursor: default;
    display: block;
    float: left;
    font-family: sans-serif;
    font-size: 12px;
    font-weight: 600;
    height: 24px;
    line-height: 17.142858505249px;
    margin-bottom: 0px;
    margin-top: 0px;
    min-height: 1px;
    padding-left: 15px;
    padding-right: 15px;
    padding-top: 7px;
    position: relative;
    text-align: right;
    visibility: visible;
    width: 89.65625px;

Is it the browser or CSS?

--UPDATE---

Ok looks like its this CSS

    .md-modal {
    	position: fixed;
    	top: 50%;
    	left: 50%;
    	width: 50%;
    	max-width: 630px;
    	min-width: 320px;
    	height: auto !important;
    	z-index: 2000;
    	visibility: hidden;
    	-webkit-backface-visibility: hidden;
    	-moz-backface-visibility: hidden;
    	backface-visibility: hidden;
    	-webkit-transform: translateX(-50%) translateY(-50%); &lt;--- This line
    	-moz-transform: translateX(-50%) translateY(-50%);
    	-ms-transform: translateX(-50%) translateY(-50%);
    	transform: translateX(-50%) translateY(-50%);
    }

However if I take it out my modal no longer centres?


  [1]: http://i.stack.imgur.com/E678e.png

Chrome Font appears Blurry

Our angular app sometime does not load on chrome canary (Version 41.0.2237.0 canary (64-bit)) saying

&gt; Failed to instantiate module ngHintModules due to: RangeError: Maximum
&gt; call stack size exceeded

But it loads fine in firefox, chrome (Version 39.0.2171.71 (64-bit)), safari.

Probably not sure whether there is something to do with angular or not. 

Full error

    Uncaught Error: [$injector:modulerr] Failed to instantiate module ngHintModules due to:
    RangeError: Maximum call stack size exceeded
        at Array.forEach (native)
        at module.exports (chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2333:21)
        at module.exports (chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2384:5)
        at chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2387:7
        at Array.forEach (native)
        at module.exports (chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2385:21)
        at chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2387:7
        at Array.forEach (native)
        at module.exports (chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2385:21)
        at chrome-extension://ighdmehidhipcmcojjgiloacoafjmpfk/dist/hint.js:2387:7


NB: The Error I am showing here is from 

&gt; Version 41.0.2237.0 canary (64-bit)

Chrome extension hint.js &amp; ngHintModules

I&#39;m trying to implement long polling for the first time, and I&#39;m using XMLHttpRequest objects to do it. So far, I&#39;ve been successful at getting events in Firefox and Internet Explorer 11, but Chrome strangely is the odd one out this time.

I can load one page and it runs just fine. It makes the request right away and starts processing and displaying events. If I open the page in a second tab, one of the pages starts seeing delays in receiving events. In the dev tools window, I see multiple requests with this kind of timing:

  ![screenshot](http://i.stack.imgur.com/qFDtX.png)

&quot;Stalled&quot; will range up to 20 seconds. It won&#39;t happen on every request, but will usually happen on several requests in a row, and in one tab.

At first I thought this was an issue with my server, but then I opened two IE tabs and two Firefox tabs, and they all connect and receive the same events without stalling. Only Chrome is having this kind of trouble.

I figure this is likely an issue with the way in which I&#39;m making or serving up the request. For reference, the request headers look like this:

    Connection: keep-alive
    Last-Event-Id: 530
    User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.71 Safari/537.36
    Accept: */*
    DNT: 1
    Accept-Encoding: gzip, deflate, sdch
    Accept-Language: en-US,en;q=0.8

The response looks like this:

    HTTP/1.1 200 OK
    Cache-Control: no-cache
    Transfer-Encoding: chunked
    Content-Type: text/event-stream
    Expires: Tue, 16 Dec 2014 21:00:40 GMT
    Server: Microsoft-HTTPAPI/2.0
    Date: Tue, 16 Dec 2014 21:00:40 GMT
    Connection: close

In spite of the headers involved, I&#39;m not using the browser&#39;s native EventSource, but rather a polyfill that lets me set additional headers. The polyfill is using XMLHttpRequest under the covers, but it seems to me that no matter how the request is being made, it shouldn&#39;t stall for 20 seconds.

What might be causing Chrome to stall like this?

**Edit:** Chrome&#39;s chrome://net-internals/#events page shows that there&#39;s a timeout error involved:

    t=33627 [st=    5]      HTTP_CACHE_ADD_TO_ENTRY  [dt=20001]
                    --&gt; net_error = -409 (ERR_CACHE_LOCK_TIMEOUT)

The error message refers to a patch added to Chrome six months ago (https://codereview.chromium.org/345643003), which implements a 20-second timeout when the same resource is requested multiple times. In fact, one of the bugs the patch tries to fix ([bug number 46104](https://code.google.com/p/chromium/issues/detail?id=46104)) refers to a similar situation, and the patch is meant to *reduce* the time spent waiting.

It&#39;s possible the answer (or workaround) here is just to make the requests look different, although perhaps Chrome could respect the &quot;no-cache&quot; header I&#39;m setting.



Chrome stalls when making multiple requests to same resource?

Ajax request occasionally stalled for a long time in chrome.

I finally managed to reproduced it and save all related data necessary to post here if anyone could help me out.

The timeline from Chrome Dev Tool shows the request stalled for 42.62s as the following screen capture shows:
![enter image description here][1]


and within the `chrome://net-internals/#events` (for the events log please head to the end) page I found the most time is cost by two events:

- +HTTP_TRANSACTION_READ_HEADERS  [dt=21301]
- +HTTP_TRANSACTION_READ_HEADERS  [dt=21304]

both get `ERR_CONNECTION_RESET`.

![enter image description here][2]

I think the error is the reason why the request stalled for so long.

Any one could explain the errors?

FOLLOWING IS THE EVENTS LOG FOR THE REQUEST, I also export the full events as json you can get from [here](https://gist.githubusercontent.com/wayou/39772215d075c80d643a/raw/9c91463f22016d20c90de19e77ae3e4f302e0769/gistfile1.txt) then restore within the Chrome `chrome://net-internals/#events` page. note the request url is internal so maybe cant access from public network:

&lt;!-- begin snippet: js hide: false --&gt;

&lt;!-- language: lang-html --&gt;

    193486: URL_REQUEST
    http://qa.tieba.baidu.com/release/getReleaseHistory?projectId=fum1.0.593
    Start Time: 2015-01-02 17:51:05.323

    t=    1 [st=    0] +REQUEST_ALIVE  [dt=42741]
    t=    1 [st=    0]    URL_REQUEST_DELEGATE  [dt=0]
    t=    1 [st=    0]   +URL_REQUEST_START_JOB  [dt=42740]
                          --&gt; load_flags = 339804160 (BYPASS_DATA_REDUCTION_PROXY | MAYBE_USER_GESTURE | REPORT_RAW_HEADERS | VERIFY_EV_CERT)
                          --&gt; method = &quot;GET&quot;
                          --&gt; priority = &quot;LOW&quot;
                          --&gt; url = &quot;http://qa.tieba.baidu.com/release/getReleaseHistory?projectId=fum1.0.593&quot;
    t=    2 [st=    1]      URL_REQUEST_DELEGATE  [dt=0]
    t=    2 [st=    1]      HTTP_CACHE_GET_BACKEND  [dt=0]
    t=    2 [st=    1]      HTTP_CACHE_OPEN_ENTRY  [dt=0]
    t=    2 [st=    1]      HTTP_CACHE_ADD_TO_ENTRY  [dt=0]
    t=    2 [st=    1]      HTTP_CACHE_READ_INFO  [dt=0]
    t=    2 [st=    1]      URL_REQUEST_DELEGATE  [dt=0]
    t=    2 [st=    1]     +HTTP_STREAM_REQUEST  [dt=2]
    t=    4 [st=    3]        HTTP_STREAM_REQUEST_BOUND_TO_JOB
                              --&gt; source_dependency = 193488 (HTTP_STREAM_JOB)
    t=    4 [st=    3]     -HTTP_STREAM_REQUEST
    t=    4 [st=    3]     +HTTP_TRANSACTION_SEND_REQUEST  [dt=0]
    t=    4 [st=    3]        HTTP_TRANSACTION_SEND_REQUEST_HEADERS
                              --&gt; GET /release/getReleaseHistory?projectId=fum1.0.593 HTTP/1.1
                                  Host: qa.tieba.baidu.com
                                  Connection: keep-alive
                                  Accept: application/json, text/plain, */*
                                  User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36
                                  Referer: http://qa.tieba.baidu.com/project/
                                  Accept-Encoding: gzip, deflate, sdch
                                  Accept-Language: en-US,en;q=0.8
                                  Cookie: [268 bytes were stripped]
    t=    4 [st=    3]     -HTTP_TRANSACTION_SEND_REQUEST
    t=    4 [st=    3]     +HTTP_TRANSACTION_READ_HEADERS  [dt=21301]
    t=    4 [st=    3]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=21301]
                              --&gt; net_error = -101 (ERR_CONNECTION_RESET)
    t=21305 [st=21304]        HTTP_TRANSACTION_RESTART_AFTER_ERROR
                              --&gt; net_error = -101 (ERR_CONNECTION_RESET)
    t=21305 [st=21304]     -HTTP_TRANSACTION_READ_HEADERS
    t=21305 [st=21304]     +HTTP_STREAM_REQUEST  [dt=3]
    t=21307 [st=21306]        HTTP_STREAM_REQUEST_BOUND_TO_JOB
                              --&gt; source_dependency = 193494 (HTTP_STREAM_JOB)
    t=21308 [st=21307]     -HTTP_STREAM_REQUEST
    t=21308 [st=21307]     +HTTP_TRANSACTION_SEND_REQUEST  [dt=3]
    t=21308 [st=21307]        HTTP_TRANSACTION_SEND_REQUEST_HEADERS
                              --&gt; GET /release/getReleaseHistory?projectId=fum1.0.593 HTTP/1.1
                                  Host: qa.tieba.baidu.com
                                  Connection: keep-alive
                                  Accept: application/json, text/plain, */*
                                  User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36
                                  Referer: http://qa.tieba.baidu.com/project/
                                  Accept-Encoding: gzip, deflate, sdch
                                  Accept-Language: en-US,en;q=0.8
                                  Cookie: [268 bytes were stripped]
    t=21311 [st=21310]     -HTTP_TRANSACTION_SEND_REQUEST
    t=21311 [st=21310]     +HTTP_TRANSACTION_READ_HEADERS  [dt=21304]
    t=21311 [st=21310]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=21304]
                              --&gt; net_error = -101 (ERR_CONNECTION_RESET)
    t=42615 [st=42614]        HTTP_TRANSACTION_RESTART_AFTER_ERROR
                              --&gt; net_error = -101 (ERR_CONNECTION_RESET)
    t=42615 [st=42614]     -HTTP_TRANSACTION_READ_HEADERS
    t=42615 [st=42614]     +HTTP_STREAM_REQUEST  [dt=12]
    t=42627 [st=42626]        HTTP_STREAM_REQUEST_BOUND_TO_JOB
                              --&gt; source_dependency = 193498 (HTTP_STREAM_JOB)
    t=42627 [st=42626]     -HTTP_STREAM_REQUEST
    t=42627 [st=42626]     +HTTP_TRANSACTION_SEND_REQUEST  [dt=2]
    t=42627 [st=42626]        HTTP_TRANSACTION_SEND_REQUEST_HEADERS
                              --&gt; GET /release/getReleaseHistory?projectId=fum1.0.593 HTTP/1.1
                                  Host: qa.tieba.baidu.com
                                  Connection: keep-alive
                                  Accept: application/json, text/plain, */*
                                  User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36
                                  Referer: http://qa.tieba.baidu.com/project/
                                  Accept-Encoding: gzip, deflate, sdch
                                  Accept-Language: en-US,en;q=0.8
                                  Cookie: [268 bytes were stripped]
    t=42629 [st=42628]     -HTTP_TRANSACTION_SEND_REQUEST
    t=42629 [st=42628]     +HTTP_TRANSACTION_READ_HEADERS  [dt=112]
    t=42629 [st=42628]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=112]
    t=42741 [st=42740]        HTTP_TRANSACTION_READ_RESPONSE_HEADERS
                              --&gt; HTTP/1.1 200 OK
                                  Date: Fri, 02 Jan 2015 09:51:48 GMT
                                  Content-Type: application/json; charset=UTF-8
                                  Transfer-Encoding: chunked
                                  Connection: keep-alive
                                  Cache-Control: no-cache
                                  tracecode: 31079600320335034634010217
                                  tracecode: 31079600320537995786010217
                                  Server: Apache
    t=42741 [st=42740]     -HTTP_TRANSACTION_READ_HEADERS
    t=42741 [st=42740]      HTTP_CACHE_WRITE_INFO  [dt=0]
    t=42741 [st=42740]      HTTP_CACHE_WRITE_DATA  [dt=0]
    t=42741 [st=42740]      HTTP_CACHE_WRITE_INFO  [dt=0]
    t=42741 [st=42740]      URL_REQUEST_DELEGATE  [dt=0]
    t=42741 [st=42740]   -URL_REQUEST_START_JOB
    t=42741 [st=42740]    URL_REQUEST_DELEGATE  [dt=0]
    t=42741 [st=42740]    HTTP_TRANSACTION_READ_BODY  [dt=0]
    t=42741 [st=42740]    HTTP_CACHE_WRITE_DATA  [dt=0]
    t=42741 [st=42740]    HTTP_TRANSACTION_READ_BODY  [dt=0]
    t=42741 [st=42740]    HTTP_CACHE_WRITE_DATA  [dt=0]
    t=42742 [st=42741] -REQUEST_ALIVE

&lt;!-- end snippet --&gt;

**EDIT:related issue** [Issue 447463:	Chrome-network: Long delay before RST message on stale sockets results in slow page loads.][3]


  [1]: http://i.stack.imgur.com/yFaPS.jpg
  [2]: http://i.stack.imgur.com/7zphy.jpg
  [3]: https://code.google.com/p/chromium/issues/detail?id=447463

request stalled for a long time occasionally in chrome

I know that using `cURL` I can see my received cookies / headers by using

    curl --head www.google.com

And I know that I can add headers to my request using

    curl --cookie &quot;Key=Value&quot; www.google.com

I am currently working on testing an issue which requires persistent cookies, and there can be a lot of them.

&gt;How can I efficiently preserve cookies between two `cURL` requests?

If possible using a temporary file for storage.

Save cookies between two curl requests

I currently have a dataframe that looks like this:

               Unnamed: 1    Unnamed: 2   Unnamed: 3  Unnamed: 4
    0   Sample Number  Group Number  Sample Name  Group Name
    1             1.0           1.0          s_1         g_1
    2             2.0           1.0          s_2         g_1
    3             3.0           1.0          s_3         g_1
    4             4.0           2.0          s_4         g_2

I&#39;m looking for a way to delete the header row and make the first row the new header row, so the new dataframe would look like this:

        Sample Number  Group Number  Sample Name  Group Name
    0             1.0           1.0          s_1         g_1
    1             2.0           1.0          s_2         g_1
    2             3.0           1.0          s_3         g_1
    3             4.0           2.0          s_4         g_2
I&#39;ve tried stuff along the lines of `if &#39;Unnamed&#39; in df.columns:` then make the dataframe without the header `df.to_csv(newformat,header=False,index=False)` but I don&#39;t seem to be getting anywhere.

Python Pandas Replacing Header with Top Row

[Retrofit 2&#39;s documentation][1] says:

&gt; Headers that need to be added to every request can be specified using an OkHttp interceptor.

It can be done easily using the previous version, [here&#39;s][2] the related QA.

But using retrofit 2, I couldn&#39;t find something like `setRequestInterceptor` or `setInterceptor` method that can be applied to `Retrofit.Builder` object.

Also it seems that there&#39;s no `RequestInterceptor` in [OkHttp][3] anymore. Retrofit&#39;s doc refers us to [Interceptor][4] that I didn&#39;t quite understand how to use it for this purpose.

How can I do this?

  [1]: http://square.github.io/retrofit/
  [2]: https://stackoverflow.com/questions/27213291/how-to-define-a-header-to-all-request-using-retrofit
  [3]: http://square.github.io/okhttp/
  [4]: https://github.com/square/okhttp/wiki/Interceptors

Adding header to all request with Retrofit 2

I want to fix my header views in the top of the screen like in the image below and without using external libraries.

[![enter image description here][1]][1]

In my case, I don&#39;t want to do it alphabetically. I have two different types of views (Header and normal). I only want to fix to the top, the last header.


  [1]: http://i.stack.imgur.com/7qE9v.gif

How can I make sticky headers in RecyclerView? (Without external lib)

I am reading a csv file into `pandas`. This csv file constists of four columns and some rows, but does not have a header row, which I want to add. I have been trying the following: 

    Cov = pd.read_csv(&quot;path/to/file.txt&quot;, sep=&#39;\t&#39;)
    Frame=pd.DataFrame([Cov], columns = [&quot;Sequence&quot;, &quot;Start&quot;, &quot;End&quot;, &quot;Coverage&quot;])
    Frame.to_csv(&quot;path/to/file.txt&quot;, sep=&#39;\t&#39;)

But when I apply the code, I get the following Error:

    ValueError: Shape of passed values is (1, 1), indices imply (4, 1)
What exactly does the error mean? And what would be a clean way in python to add a header row to my csv file/pandas df?



How to add header row to a pandas DataFrame

I&#39;ve been reading up on `CORS` and how it works, but I&#39;m finding a lot of things confusing. For example, there are lots of details about things like 

&gt; User `Joe` is using browser `BrowserX` to get data from `site.com`,
&gt; which in turn sends a request to `spot.com`. To allow this, `spot` has
&gt; special headers... yada yada yada

Without much background, I don&#39;t understand why websites wouldn&#39;t let requests from some places. I mean, they exist to serve responses to requests, don&#39;t they? Why would certain people&#39;s of requests not be allowed?

It would really appreciate a nice explanation (or a link to one) of the problem that `CORS` is made to solve.

So the question is,

**What is the problem `CORS` is solving?**

What is the issue CORS is trying to solve?

I have some trouble understanding the same-origin policy and the different ways to &quot;workaround&quot; it.&lt;br&gt;&lt;br&gt;
It is clear that the same-origin policy exists as a security measure, so one script that comes from a server/domain has no access to data coming from another server/domain.&lt;br&gt;&lt;br&gt;
It is also clear that sometimes, it is useful to be able to break this rule, so for example a mashup application accesses information from different servers in order to build up the results wanted. And one of the ways to do this is CORS.&lt;br&gt;&lt;br&gt;
1) If I&#39;m not wrong, CORS allows **the target server** to say to the browser &quot;*it is ok for you to take data/code from myself*&quot; by adding some headers in the response. But, if this is correct, this means that a malicious server could just add this header and the browser would allow the retrieval of any data or code, potentially harmful, coming from that server.&lt;br&gt;&lt;br&gt;
2) On the other side, we have JSONP, allowing us to retrieve arbitrary code or data from a server without CORS enabled, thus avoiding the main goal of the SOP. So again, a malicious server able to manage JSONP is able to inject data or code even with the SOP hardwired in the browser.&lt;br&gt;&lt;br&gt;
So my questions are:&lt;br&gt;&lt;br&gt;
Is the second argumentation correct? Is it the decision of the server whether the browser must accept the contents?&lt;b&gt;&lt;b&gt;
Is the second argumentation correct? It is, again, not in the browser&#39;s decision whether to accept or not data?&lt;br&gt;&lt;br&gt;
Does not JSONP render the SOP useless?&lt;br&gt;&lt;br&gt;
Thanks for enlightening me!!&lt;br&gt;


same-origin policy and CORS - what&#39;s the point?

I have a problem with the `--disable-web-security` flag. It is not working in Chrome 48 and Chrome 49 beta on Windows.

I&#39;ve tried killing all of the instances, reboot and run Chrome with the flag first of all, tried different machines as well. In the beta I can see the warning popup (&quot;You are using unsupported flag..&quot;), but CORS is still being enforced. Public version seems to ignore the flag completely. 

There seems to be no news or people reports about that, so it might be a local issue. 
Will be grateful for help or any related info.

Disable-web-security in Chrome 48+

##tl;dr; About the Same Origin Policy

I have a Grunt process which initiates an instance of express.js server. This was working absolutely fine up until just now when it started serving a blank page with the following appearing in the error log in the developer&#39;s console in Chrome (latest version):
  
&gt;XMLHttpRequest cannot load https://www.example.com/
    No &#39;Access-Control-Allow-Origin&#39; header is present on the requested 
    resource. Origin &#39;http://localhost:4300&#39; is therefore not allowed access.

What is stopping me from accessing the page?

Content Type	Original Author	Original Content on Stackoverflow
Question	Øystein Drabløs	View Question on Stackoverflow
Solution 1 - Web Services	Joffrey Maheo	View Answer on Stackoverflow
Solution 2 - Web Services	RAHUL KUMAR	View Answer on Stackoverflow

Origin evil.com in Request Header

Web Services Problem Overview

Web Services Solutions

Solution 1 - Web Services

Solution 2 - Web Services

print the unique values in every column in a pandas dataframe

How to set image for bar button with swift?

Attributions