Writing a simple webservice in python

There are two common formats that we use when exchanging data across the web. The "eXtensible Markup Language" or XML has been in use for a very long time and is best suited for exchanging document-style data. When programs just want to exchange dictionaries, lists, or other internal information with each other, they use JavaScript Object Notation or JSON see www.

Writing a simple webservice in python

Features of http clients should support - 1. Caching Network access is incredibly expensive! The most important thing to realize that any type of web service is that network access is incredibly expensive. It takes an extraordinary long time to open a connection, send a request, and retrieve a response from a remote server.

Even on the fastest broadband connection, a latency can still be higher than we anticipated. A router misbehaves, a packet is dropped, an intermediate proxy is under attack, and so on. There is an entire class of devices called caching proxies whose only job is to sit between us and the rest of the world and minimize network access.

Our company or ISP almost certainly maintains caching proxies, even if we're not aware of them. They work because caching is built into the http protocol. Chrome we can get header http header info: We can use Cache-Control: This way we avoid unneeded further requests if browser already has the component in its cache and therefore primed-cache page views will be performed faster.

The following example shows the response to the request of an image. That page includes an image. When our browser downloads that image, the server includes the following http headers: So, let's look at another site: The Cache-Control and Expires headers tell our browser and any caching proxies between us and the server that this image can be cached for up to 2 minutes from Sun, 20 Jan And if, within that period, we visit the page, our browser will load the page from its cache without generating any network activity whatsoever.

But let's suppose, we're trying to download an image and we have about a month before it expires. And our browser purges the image from our local cache for some reason. But the http headers said that this data could be cached by public caching proxies. Technically, the important thing is what the headers don't say; the Cache-Control header doesn't have the private keyword, so this data is cacheable by default.

Caching proxies are designed to have tons of storage space, probably far more than our local browser has allocated. If our ISP maintain a caching proxy, the proxy may still have the image cached.

When we visit the site again, our browser will look in its local cache for the image, but it won't find it, so it will make a network request to try to download it from the remote server.

But if the caching proxy still has a copy of the image, it will intercept that request and serve the image from its cache. That means that our request will never reach the remote server; in fact, it will never leave our ISP's network.

That makes for a faster download fewer network hops. On one side, servers need to send the correct headers in their response. On the other side, clients need to understand and respect those headers before they request the same data twice.

The proxies in the middle are not a panacea; they can only be as smart as the servers and clients allow them to be. Python's http libraries do not support caching, but httplib2 does.

Create a simple REST web service with Python

Features of http clients should support - 2. Last modified checking Some data never changes, while other data changes all the time. In between, there is a vast field of data that might have changed, but hasn't.

In the latter case, I don't want to tell clients to cache my feed for weeks at a time, because then when I do actually post something, people may not read it for weeks because they're respecting my cache headers which said don't bother checking this feed for weeks.

What We’re Building

On the other hand, I don't want clients downloading my entire feed once an hour if it hasn't changed! When we request data for the first time, the server can send back a Last-Modified header.Find helpful customer reviews and review ratings for Elements of Programming Interviews: The Insiders' Guide at caninariojana.com Read honest and unbiased product reviews from our users.

Designing a RESTful API with Python and Flask. Posted by Miguel Grinberg under Python, Programming, REST, Designing a simple web service. Let's say we want to write a To Do List application and we want to design a web service for it.

writing a simple webservice in python

The first thing to do is to decide what is the root URL to access this service. MSDN Magazine Issues and Downloads. Read the magazine online, download a formatted digital version of each issue, or grab sample code and apps. Webservices written with soaplib are simple, lightweight, work well with other SOAP implementations, and can be deployed as WSGI applications.

suds - Suds is a lightweight SOAP python client that provides a service proxy for Web Services. Directory of computer-aided Drug Design tools Click2Drug contains a comprehensive list of computer-aided drug design (CADD) software, databases and web services. Create a simple REST web service with Python.

This is a quick tutorial on how to create a simple RESTful web service using python. The rest service uses caninariojana.com to create a server and it will have two URLs, one for accessing all users and one for accessing individual users.

WebServices - Python Wiki