Has SOAP exclusively used HTTP POST historically for HTTP? - http

Has SOAP exclusively used HTTP POST historically? In other words, does SOAP mainly use HTTP POST for all types of request? In comparison, the RESTful approach may be to use request types closely matching the purpose of the message. I wondered what the current and historical stance has been for SOAP.

SOAP mainly considers the use of HTTP POST historically (though can use other protocols such as SMTP) for request and response since version 1.1. However, since version 1.2 it can use GET requests with no SOAP message receiving a SOAP response. (Papazoglou, Michael P. (2008). Web Services: Principles and Technology. Harlow: Pearson Education Limited. p140-143.)

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WCF Rest vs WebAPi

One of the difference which I read is "Unlike WCF Rest we can use full features of HTTP in Web API"
WebApi and wcf rest both uses Http only but I am not sure what do we mean by full features of Http here.
What are the Http features which are available in webApi but not in wcf rest.
Could somebody explain please.
I think WebAPI is better than WCF because of some points of HTTP features:
Support many formats: JSON, XML, Text, binary, ...
Can customize Header and Body
Easy to custom URL
Simpler and faster (WCF is SOAP-based service)
Support many HTTP Status codes
Support multiple devices because the simple response and easy to customize for small devices like phone

In what use cases is a web service likely to receive OPTIONS requests other than CORS?

I have recently implemented a CORS IDispatchMessageInspector applied through a BehaviorExtensionElement for services within a large project I am working on to allow for CORS support (arising from calling REST WCF web services from jQuery Ajax calls).
The current implementation intercepts all OPTIONS method calls to an endpoint with the CORS behavior specified and responds with the appropriate headers (and a 200). As it stands the service will expect to see OPTIONS requests only in the case of CORS requests, however I cannot guarantee that this will always be the case.
In the interests of future proofing and extensibility, what are the most common reasons for OPTIONS requests outside of CORS? Are there plans to extend the use of such requests in future WC3 specs (as this seems to suggest)? Are there any use cases that I should attempt to allow for?
It's the other way around.
A CORS preflight request will be an OPTIONS request including an Origin and Access-Control-Request-Method request header, by which you can recognize it as such.
Any other OPTIONS request is just that, and can be sent by any client for any reason.
WebDAV clients are known to use OPTIONS to probe for support for protocol levels and method support (see RFC 4918).

REST: HTTP headers or request parameters

I've been putting in some research around REST. I noticed that the Amazon S3 API uses mainly http headers for their REST interface. This was a surprise to me, since I assumed that the interface would work mainly off request parameters.
My question is this: Should I develop my REST interface using mainly http headers, or should I be using request parameters?
The question mainly is whether the parameters defined are part of the resource identifier (URI) or not. if so, then you would use the request parameters otherwise HTTP custom headers. For example, passing the id of the album in a music gallery must be part of the URI.
Remember, for example /employee/id/45 (Or /employee?id=45, REST does not have a prejudice against query string parameters or for clean slash separated URIs) identifies one resource. Now you could use content-negotiation by sending request header content-type: text/plain or content-type: image/jpg to get the info or the image. In this respect, resource is deemed to be the same and header only used to define format of the resource.
Generally, I am not a big fan of HTTP custom headers. This usually assumes the client to have a prior knowledge of the server implementation (not discoverable through natural HTTP means, i.e. hypermedia) which always is considered a REST anti-pattern
HTTP headers usually define aspects of HTTP orthogonal to what is to be achieved in the process of request/response. Authorization header (really a misnomer, should have been authentication) is a classic example.

SOAP and HTTP Post

I have an ASP.NET web service running that accepts both HTTP POST and SOAP requests. Are there any disadvantages to using a simple HTTP POST to get the data from the WS instead of using SOAP over HTTP?
I can't think of anything else other than the support for transmission of complex data types, and I don't think I'll need that in this project.
Thanks,
Teja.
The clue is in the question...
using a simple HTTP POST to get the data
A POST is not a GET, a GET is a GET.
If you're the only person operating on the WS then it's not a problem as long as you are handling your incoming connections properly. If it is open to outsiders then I would recommend sticking to conventions, they are there to save us from ourselves :)

Passing params in the URL when using HTTP POST

Is it allowable to pass parameters to a web page through the URL (after the question mark) when using the POST method? I know that it works (most of the time, anyways) because my company's webapp does it often, but I don't know if it's actually supported in the standard or if I can rely on this behavior. I'm considering implementing a SOAP request handler that uses a parameter after the question mark to indicate that it is a SOAP request and not a normal HTTP request. The reason for this that the webapp is an IIS extension, so everything is accessed via the same URL (ex: example.com/myisapi.dll?command), so to get the SOAP request to be processed, I need to specify that "command" parameter. There would be one generic command for SOAP, not a specific command for each SOAP action -- those would be specified in the SOAP request itself.
Basically, I'm trying to integrate the Apache Axis2/C library into my webapp by letting the webapp handle the HTTP request and then pass off the incoming SOAP XML to Axis2 for handling if it's a SOAP request. Intuitively, I can't see any reason why this wouldn't work, since the URL you're posting to is just an arbitrary URL, as far as all the various components are concerned... it's the server that gives special meaning to the parts after the question mark.
Thanks for any help/insight you can provide.
Lets start with the simple stuff. HTTP GET request variables come from the URI. The URI is a requested resource, and so any webserver should (and apache does) have the entire URI stored in some variable available to the modules or appserver components running within the webserver.
An http POST which is different from an http GET is a separate logical call to the webserver, but it still defines a URI that should process the post. A good webserver (apache being one) will again make the URI available to whatever module or appserver is running within it, then will additionally make available the variables which were sent in the POST headers.
At the point where your application takes control from apache during a POST you should have access to both the GET and POST variables and be able to do whatever control logic you wish, including replying with a SOAP protocol instead of HTML.
If you are asking whether it is possible to send parameters via both GET and POST in a single HTTP request, then the answer is "YES". This is standard functionality that can be used reliably AFAIK.
One such example is sending authentication credentials in two pieces, one over GET and the other through POST so that any attempt to hijack a session would require hijacking both the GET and POST variables.
So in your case, you can use POST to contain the actual SOAP request but test for whether it is a SOAP request based on the parameter passed in GET (or in other words through the URL).
I believe that no standard actually defines the concept of "HTTP parameters" or "request variables". RFC 1738 defines that an URL may have a "search part", which is the substring after the question mark. HTML specifies in the form submission protocol how a browser processing a FORM element should submit it. In either case, how the server-side processes both the search part and the HTTP body is entirely up to the server - discarding both would be conforming to these two specs (but fairly useless).
In order to determine whether you can post a search part to a specific service, you need to study this service's protocol specification. If the service is practically defined by means of a HTML form, then you cannot use a mix - you can't even use POST if the FORM specifies GET (and vice versa). If you post to a web service, you need to look at the web service's WSDL - which will typically mandate POST; with all data in a SOAP message. Etc.
Specific web frameworks may have the notion of "request variables" - whether they will draw these variables both from a search part and a request body, you need to find out in the product documentation.
I deployed a web application with 3 (a mobile network operator) in the UK. It originally used POST parameters, but the 3 gateway stripped them (and X-headers as well!). So beware...
allowable? sure, it's doable, but i'm leaning towards the spec suggesting dual methods isn't necessarily supposed to happen, or be supported. RFC2616 defines HTTP/1.1, and i would argue suggests only one method per request. if you think about your typical HTTP transaction from the client side, you can see the limitation as well:
$ telnet localhost 80
POST /page.html?id=5 HTTP/1.1
host: localhost
as you can see, you can only use one method (POST/GET, etc...), however due to the nature of how various languages operate, they may pick up the query string, and assign it to the GET variable. ultimately though, this is a POST request, and not a GET.
so basically, yes this functionality exists, is it intended? i would say no.

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