I want to fetch some specific HTTP headers of a file like
Content-Type
Content-Length
before downloading the actual file. How can I retrieve them? Thanks.
You should use the HTTP method HEAD. This only retrieves the headers, but does not load the actual contents. Something like this will probably do the trick
$client = new \GuzzleHttp\Client();
$client->request('HEAD', 'http://httpbin.org/get');
I'm building an api at my company using laravel.
The problem I'm encountering is that if you send an api request without defining the correct header with the request you will get html back if there is a failure e.g. authorization failure or findOrFail() failure.
My thinking is that you never want to return html (even if the user has the wrong header).
I have a couple of solutions. In BeforeMiddleware.php I can manually insert a header into the request such as:
// Check if we are on an api route
$apiRoute = strncmp($uri, '/api/', 5) == 0;
// Insert the request header to force json response
if ($apiRoute){
$language = $request->header->add('Accept', 'application/json');
}
The 2nd solutions would be to throw an error if they don't have the correct header.
What would be the best way to enforce a json response, what is a good practice for handling api responses in laravel?
Once you detected that you are on your api path you are out of the woods and can indeed tackle your problem in the app\Exceptions\Handler.php file like suggested on How do you force a JSON response on every response in Laravel?.
For an open source project I created JSON exception objects by Microsoft format as output, but you can choose the jsonapi format (http://jsonapi.org/examples/#error-objects-basics) as you like:
https://github.com/StadGent/laravel_site_opening-hours/blob/develop/app/Exceptions/Handler.php
(note that on this implementation it is indeed depending from the headers, but you can use your path detection I think)
I want to send a custom HTTP response back to an application requesting a GET to a php script. The body is will be in binary format (octet-streams). I'm wondering if there is a simple way to do this? I am looking into the HttpResponse class in PECL but is having trouble installing it right now. I do not really need all the other functionalities that goes with it so I'm looking for something simpler.
Any help would be appreciated.
PHP has a header() function built in, so you can customise your response without requiring extra libraries:
<?php
header('Content-Type: application/octet-stream');
header('X-Powered-By: l3utterfly');
echo $binary_data;
?>
You can always set HTTP Headers using header() function, and then simply output binary data using print, echo or any other usual way. Send Content-Type http header to octet stream and it should work all right.
You can use the header function to send back whatever response you want. If you want to send back custome response codes, you could use:
<?
$protocol = (isset($_SERVER['SERVER_PROTOCOL']) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0');
//change the code and message to whatever. But I would keep it valid codes so browsers can handle it.
//see http://en.wikipedia.org/wiki/List_of_HTTP_status_codes
header($protocol . ' 404 Not Found');
exit();
?>
And if you want to send binary data, change the header to the correct content-type and echo the binary data.
I am quite experienced in PHP but I've always had troubles with connection between servers like "post". I have a FLAC audio file that I need to post to Google's Speech Recognition API server. I don't know neither how to "listen" to its response. I would like a script like that, assuming that this kind of function exists :
<?php
$fileId = $_GET['fileId'];
$filepath = $fileId . ".flac";
recognize($filepath);
function recognize($pathToFile) {
//It's the following function that I'm looking for
$response = $pathToFile->post("http://www.google.com/speech-api/v1/.....&client=chromium");
//The $response would be the short JSON that Google feed back.
echo $response;
}
?>
EDIT
I've followed a tutorial to create a Shell Script that posts my FLAC file using Wget --post. I would like to post like this, but in PHP. Also, at the end of the command, there is this > answer.ret line, so that Google's answer would be written to this file. I was wondering if there was an alternate method to it in PHP.
Here's the command line :
wget -q -U "Mozilla/5.0" --post-file audio1.flac --header="Content-Type: audio/x-flac; rate=16000" -O - "http://www.google.com/speech-api/v1/recognize?lang=fr-fr&client=chromium" > trancription1.ret
EDIT 2
I figured out how to do it, with #hakre 's answer and baked up a little Gist for curious people. Here it is: https://gist.github.com/chlkbumper/4969389. Don't forget that the FLAC file must be a 16k bitrate FLAC
A POST request is just a standard HTTP request, just with the POST method specified. The rest of the HTTP Request and HTTP Response is pretty much the same.
You get the response of a request in form of a HTTP Response btw.. It is absolutely normaltiv defined in RFC 2616 - just relate to this document and it explains everything.
A function in PHP to send HTTP requests is file_get_contents, it returns the requests response. This is done via the HTTP stream wrapper that offers some options you need to send a POST request (default is GET). See HTTP context options.
Another popular PHP extension for sending HTTP requests are the Curl bindings.
This is something that has been bugging me for a while.. I'm building of a RESTful API that has to receive files on some occasions.
When using HTTP POST, we can read data from $_POST and files from $_FILES.
When using HTTP GET, we can read data from $_GET and files from $_FILES.
However, when using HTTP PUT, AFAIK the only way to read data is to use the php://input stream.
All good and well, untill I want to send a file over HTTP PUT. Now the php://input stream doesn't work as expected anymore, since it has a file in there as well.
Here's how I currently read data on a PUT request:
(which works great as long as there are no files posted)
$handle = fopen('php://input', 'r');
$rawData = '';
while ($chunk = fread($handle, 1024)) {
$rawData .= $chunk;
}
parse_str($rawData, $data);
When I then output rawData, it shows
-----ZENDHTTPCLIENT-44cf242ea3173cfa0b97f80c68608c4c
Content-Disposition: form-data; name="image_01"; filename="lorem-ipsum.png"
Content-Type: image/png; charset=binary
�PNG
���...etc etc...
���,
-----ZENDHTTPCLIENT-8e4c65a6678d3ef287a07eb1da6a5380
Content-Disposition: form-data; name="testkey"
testvalue
-----ZENDHTTPCLIENT-8e4c65a6678d3ef287a07eb1da6a5380
Content-Disposition: form-data; name="otherkey"
othervalue
Does anyone know how to properly receive files over HTTP PUT, or how to parse files out of the php://input stream?
===== UPDATE #1 =====
I have tried only the above method, don't really have a clue as to what I can do else.
I have gotten no errors using this method, besides that I don't get the desired result of the posted data and files.
===== UPDATE #2 =====
I'm sending this test request using Zend_Http_Client, as follows:
(haven't had any problems with Zend_Http_Client so far)
$client = new Zend_Http_Client();
$client->setConfig(array(
'strict' => false,
'maxredirects' => 0,
'timeout' => 30)
);
$client->setUri( 'http://...' );
$client->setMethod(Zend_Http_Client::PUT);
$client->setFileUpload( dirname(__FILE__) . '/files/lorem-ipsum.png', 'image_01');
$client->setParameterPost(array('testkey' => 'testvalue', 'otherkey' => 'othervalue');
$client->setHeaders(array(
'api_key' => '...',
'identity' => '...',
'credential' => '...'
));
===== SOLUTION =====
Turns out I made some wrong assumptions, mainly that HTTP PUT would be similar to HTTP POST. As you can read below, DaveRandom explained to me that HTTP PUT is not meant for transferring multiple files on the same request.
I have now moved the transferring of formdata from the body to url querystring. The body now holds the contents of a single file.
For more information, read DaveRandom's answer. It's epic.
The data you show does not depict a valid PUT request body (well, it could, but I highly doubt it). What it shows is a multipart/form-data request body - the MIME type used when uploading files via HTTP POST through an HTML form.
PUT requests should exactly compliment the response to a GET request - they send you the file contents in the message body, and nothing else.
Essentially what I'm saying is that it is not your code to receive the file that is wrong, it is the code that is making the request - the client code is incorrect, not the code you show here (although the parse_str() call is a pointless exercise).
If you explain what the client is (a browser, script on other server, etc) then I can help you take this further. As it is, the appropriate request method for the request body that you depict is POST, not PUT.
Let's take a step back from the problem, and look at the HTTP protocol in general - specifically the client request side - hopefully this will help you understand how all of this is supposed to work. First, a little history (if you're not interested in this, feel free to skip this section).
History
HTTP was originally designed as a mechanism for retrieving HTML documents from remote servers. At first it effectively supported only the GET method, whereby the client would request a document by name and the server would return it to the client. The first public specification for HTTP, labelled as HTTP 0.9, appeared in 1991 - and if you're interested, you can read it here.
The HTTP 1.0 specification (formalised in 1996 with RFC 1945) expanded the capabilities of the protocol considerably, adding the HEAD and POST methods. It was not backwards compatible with HTTP 0.9, due to a change in the format of the response - a response code was added, as well as the ability to include metadata for the returned document in the form of MIME format headers - key/value data pairs. HTTP 1.0 also abstracted the protocol from HTML, allowing for the transfer of files and data in other formats.
HTTP 1.1, the form of the protocol that is almost exclusively in use today is built on top of HTTP 1.0 and was designed to be backwards compatible with HTTP 1.0 implementations. It was standardised in 1999 with RFC 2616. If you are a developer working with HTTP, get to know this document - it is your bible. Understanding it fully will give you a considerable advantage over your peers who do not.
Get to the point already
HTTP works on a request-response architecture - the client sends a request message to the server, the server returns a response message to the client.
A request message includes a METHOD, a URI and optionally, a number of HEADERS. The request METHOD is what this question relates to, so it is what I will cover in the most depth here - but first it is important to understand exactly what we mean when we talk about the request URI.
The URI is the location on the server of the resource we are requesting. In general, this consists of a path component, and optionally a query string. There are circumstances where other components may be present as well, but for the purposes of simplicity we shall ignore them for now.
Let's imagine you type http://server.domain.tld/path/to/document.ext?key=value into the address bar of your browser. The browser dismantles this string, and determines that it needs to connect to an HTTP server at server.domain.tld, and ask for the document at /path/to/document.ext?key=value.
The generated HTTP 1.1 request will look (at a minimum) like this:
GET /path/to/document.ext?key=value HTTP/1.1
Host: server.domain.tld
The first part of the request is the word GET - this is the request METHOD. The next part is the path to the file we are requesting - this is the request URI. At the end of this first line is an identifier indicating the protocol version in use. On the following line you can see a header in MIME format, called Host. HTTP 1.1 mandates that the Host: header be included with every request. This is the only header of which this is true.
The request URI is broken into two parts - everything to the left of the question mark ? is the path, everything to the right of it is the query string.
Request Methods
RFC 2616 (HTTP/1.1) defines 8 request methods.
OPTIONS
The OPTIONS method is rarely used. It is intended as a mechanism for determining what kind of functionality the server supports before attempting to consume a service the server may provide.
Off the top of my head, the only place in fairly common usage that I can think of where this is used is when opening documents in Microsoft office directly over HTTP from Internet Explorer - Office will send an OPTIONS request to the server to determine if it supports the PUT method for the specific URI, and if it does it will open the document in a way that allows the user to save their changes to the document directly back to the remote server. This functionality is tightly integrated within these specific Microsoft applications.
GET
This is by far and away the most common method in every day usage. Every time you load a regular document in your web browser it will be a GET request.
The GET method requests that the server return a specific document. The only data that should be transmitted to the server is information that the server requires to determine which document should be returned. This can include information that the server can use to dynamically generate the document, which is sent in the form of headers and/or query string in the request URI. While we're on the subject - Cookies are sent in the request headers.
HEAD
This method is identical to the GET method, with one difference - the server will not return the requested document, if will only return the headers that would be included in the response. This is useful for determining, for example, if a particular document exists without having to transfer and process the entire document.
POST
This is the second most commonly used method, and arguably the most complex. POST method requests are almost exclusively used to invoke some actions on the server that may change its state.
A POST request, unlike GET and HEAD, can (and usually does) include some data in the body of the request message. This data can be in any format, but most commonly it is a query string (in the same format as it would appear in the request URI) or a multipart message that can communicate key/value pairs along with file attachments.
Many HTML forms use the POST method. In order to upload files from a browser, you would need to use the POST method for your form.
The POST method is semantically incompatible with RESTful APIs because it is not idempotent. That is to say, a second identical POST request may result in a further change to the state of the server. This contradicts the "stateless" constraint of REST.
PUT
This directly complements GET. Where a GET requests indicates that the server should return the document at the location specified by the request URI in the response body, the PUT method indicates that the server should store the data in the request body at the location specified by the request URI.
DELETE
This indicates that the server should destroy the document at the location indicated by the request URI. Very few internet facing HTTP server implementations will perform any action when they receive a DELETE request, for fairly obvious reasons.
TRACE
This provides an application-layer level mechanism to allow clients to inspect the request it has sent as it looks by the time it reaches the destination server. This is mostly useful for determining the effect that any proxy servers between the client and the destination server may be having on the request message.
CONNECT
HTTP 1.1 reserves the name for a CONNECT method, but does not define its usage, or even its purpose. Some proxy server implementations have since used the CONNECT method to facilitate HTTP tunnelling.
I've never tried using PUT (GET POST and FILES were sufficient for my needs) but this example is from the php docs so it might help you (http://php.net/manual/en/features.file-upload.put-method.php):
<?php
/* PUT data comes in on the stdin stream */
$putdata = fopen("php://input", "r");
/* Open a file for writing */
$fp = fopen("myputfile.ext", "w");
/* Read the data 1 KB at a time
and write to the file */
while ($data = fread($putdata, 1024))
fwrite($fp, $data);
/* Close the streams */
fclose($fp);
fclose($putdata);
?>
Here is the solution that I found to be the most useful.
$put = array();
parse_str(file_get_contents('php://input'), $put);
$put will be an array, just like you are used to seeing in $_POST, except now you can follow true REST HTTP protocol.
Use POST and include an X- header to indicate the actual method (PUT in this case). Usually this is how one works around a firewall which does not allow methods other than GET and POST. Simply declare PHP buggy (since it refuses to handle multipart PUT payloads, it IS buggy), and treat it as you would an outdated/draconian firewall.
The opinions as to what PUT means in relation to GET are just that, opinions. The HTTP makes no such requirement. It simply states 'equivalent' .. it is up to the designer to determine what 'equivalent' means. If your design can accept a multi-file upload PUT and produce an 'equivalent' representation for a subsequent GET for the same resource, that's just fine and dandy, both technically and philosophically, with the HTTP specifications.
Just follow what it says in the DOC:
<?php
/* PUT data comes in on the stdin stream */
$putdata = fopen("php://input", "r");
/* Open a file for writing */
$fp = fopen("myputfile.ext", "w");
/* Read the data 1 KB at a time
and write to the file */
while ($data = fread($putdata, 1024))
fwrite($fp, $data);
/* Close the streams */
fclose($fp);
fclose($putdata);
?>
This should read the whole file that is on the PUT stream and save it locally, then you could do what you want with it.