Introduction
Web services are one of the developments that accompanied the increased use of internet. This implies that web developers had to constantly review the approaches used to access web content, and so was the development of the web services technology. This essay provides an overview of Python language and how it is related to the development of web services.
This essay provides an insight into Python programming language by highlighting the key concepts associated with the language and on overview of the development of web services using Python. In addition, the essay highlights the survey tools that can facilitate the development of web services in Python programing language.
Background
Python programming language is one of dynamic and object-oriented programming languages used for the development of diverse kinds of software developed by the Python Software foundation. Its significant advantage is that facilitates integration with other programing languages and software development tools. In addition, it has in-built standard libraries that are extensive. This means that it facilitates the development of a better source code.
The programming paradigm of Python language embarks on the readability of the source code enhanced through clear syntax. Apart from object-oriented programming paradigm, Python can implement other programming methodologies such as functional programing and imperative programming (Beazley 67).
Another important feature of Python language that makes it suitable as a software development tool is that it has a dynamic type system and its memory management strategy is automatic. In addition, it can support the implementation of scripting applications. It is important to note that the development model of Python language is community based, implying that its reference implementation is free and bases on the open source platform. There are various interpreters for the language for various systems software, although programs developed by Python are executable in any environment irrespective of operating system environment (Hetland 78).
Brief history of Python programming language
The development of Python language began during the late 80s, with its implementation done on the December of 1989. Python was a successor of the ABC programming language, which had the capabilities of exception handling and implementing an interface with the Amoeba System Software. The release of Python 2.0 during 2000 saw the inclusion of newer features such as offering support for Unicode and garbage collection (Beazley 89).
The significant change was its transformation making its development process community based. The release of Python 3.0 took place during 2008. Python language boasts of winning two awards by the TIOBE as the programming of language of the year during 2007 and 2010, resulting to an increase in the popularity of the language (Hetland 56).
Implementation of web services in Python
A web service is defines as a program that can transform any client application to a web-based application. The development of web services significantly depends on the scripting abilities of a programming language. An important aspect of Python language is that it can be used in scripting, implying that it is an effective development tool for web services. Web services developed by Python function using the standard messaging formats and they can be interfaced with other software development tools using the conventional Application Programming Interface (API).
Web programming using Python entails two major paradigms: server programming and client programming (Beazley 90). Server programming entails the development of web services that run on the web server, while client programming entails the development of web services that that run on the client side (Hetland 90). There are diverse approaches to server programming, examples include the WebFrameworks used for development of server side services using Python; CgiScripts used to write scripting applications in Python; Webservers, which are server solutions developed using Python.
Web services developed in Python are primarily used to offer access and functionality of the APIs via the web. On the client side, Python language can be used in a number of ways including Web Browser Programming, Web Client Programming and Web services. There are various libraries in Python for the development of web services; examples include the Simple Object Access Protocol (SOAP) and the Web Services Description Language (WSDL).
Python language has extensive in-built tools that can provide support to Internet protocols, coupled with its code readability characteristic, Python is therefore one of the most appropriate programming languages that can be used in the development of dynamic web content using the concept of dynamic programming. Some of the in-built facilities included in Python that can facilitate dynamic programming and development of web services include (Beazley 123):
- Python comes with HTTP 1.1 server implementations, which has both file servers and CGI servers. An important feature of this characteristic is that their customization is easy and they incorporate the concept of automation of web tasks. HTTP 1.1 has tools for the implementation of HTTP requests. In addition, HTTP 1.1 implements secure web services.
- Another important feature of Python is that is has features used for parsing and constructing of Uniform Resource Locators (URLs). This is used to facilitate the handling of URLs by the web service in a more efficient manner.
- Python also has an included HTML and SGML modules used for parsing HTML tags during the development of web services. SGNL is a part of the parent language of Python language.
- Python can also support XML since it has in-built XML parsing features and SAX libraries embedded in the standard library.
- Python can also handle CGI requests, facilitating the process of developing codes for handling CGI.
- Low-level sockets serve to enhance network programming, which is an important strategy in the development web based applications.
Web Frameworks used in the development of web services in Python language
A web framework is an important aspect in the development of web services and web-based applications. They allow the web developer to design web services without the need deploy low-level protocols and sockets. Most of the available web frameworks technology based on server side scripting, with a few frameworks supporting client side scripting (Hetland 122).
Python language uses web frameworks for the development of web services through providing an avenue through which web developers can simply write codes basing on some standards of conformity to that particular framework. This concept of web service development in Python is known as plugging. Python language web frameworks provide diverse activities such as the interpretation of requests, production of responses and persistent data storage.
These processes are an integral part of the web services development (Beazley 67). An example of Python web frameworks is the Full stack frameworks, which consists of high-level components such as Django, Grok, Pylons and TurboGears. Python language can support other full stack web frameworks. The ability of Python language to support diverse web frameworks makes it one of the best programming languages that can be used for web service development.
In addition, they provide an avenue through which web developers can develop codes for web services (Drake 127). Python language frameworks also have the feature of customization, meaning that Python can be used to create abstractions, which can be used to implement specific tasks during the development of web service and their respective clients (Beazley 67).
Python language tool kits used in the development of web services
The two basic Python tool kits used in web service development are the gSOAP and the ZSI. The ZSI package found in Python has in-built capabilities that can support SOAP 1.1 messaging formats and WSDL frameworks. Web service development is easy to implement using ZSI package. The gSOAP toolkit also provides an effective platform for code development aimed implementing web services in Python language. Technologies such as JSON-RPC and SOAP also favor the development of codes for web services.
Under the JSON-RPC, Python-json-rpc is used in the development of web services. Environments such as the WSDL and Windows Common Foundation (WCF) on the other hand favor SOAP, which technologies such as Suds, Soaplib, psimblesoap and ZSI. It is also important to note that Python can be embedded in XML to develop web services under the XML-RPC platform. This comes as a provision in the inbuilt library of Python programming language (Drake 100).
The implementation of HTTP web services in python
HTTP web services are primarily used for exchanging data between various remote servers and clients. For instance, the HTTP GET is used to search for data in the server, while the HTTP POST is used for sending data to the remote server. There are other diving in operations implemented in HTTP web services using Python language.
They are used for data modification, creation and deletion operations. The significant advantage of the diving in strategy during code development for web services is due to the underlying simplicity compared to other web services development strategies using python language (Drake 102). Python has a number of libraries used for the implementation of web services basing on http platform. They are the http.client and the urllib.request.
The http.client is used to implement RFC 2616, while the url.lib provides a framework for development of standardized Application Program Interface. Another third-party library is httplib2, is an open source library used in the implementation of http in a more advanced manner compared to above libraries. The following section outlines the implementation of SOAP requests using Python programming language (Hetland 134).
SOAP (Simple Object Access Protocol)
SOAP is a protocol that is used for exchange of structured messaging formats during the development and implementation of web services. SOAP significantly relies on XML for the design of its message format. On addition, it also depends on protocols that are found in the application layer such as Remote Procedure Calls and HTTP in order to facilitate the transmission of the message.
An important characteristic of SOAP is that it can be used to form an integral part of the web services protocol stack, which are used for offering the framework for messaging. Messaging frameworks play an important role in the development of code for web services. This implies that programming languages, such as Python, that have messaging frameworks are effective in web services development. The three basic elements of the SOAP protocol based on the XML framework are the envelope, data types and conventions.
The envelope defines the elements contained in the message and the various approaches used in message processing (Drake 145). The convention is a set of procedures used to represent the SOAP requests and responses. As an instance of how SOAP requests and responses can be implemented, messages that are in the SOAP framework are sent to a web page that has the capability to handle web services.
An example of such a website can be a library database that has some specified search parameters to distinguish the various database elements such as year of publication, author name and so on. If the search data that is supposed to be returned is changed into a format that is standardized and based on the machine-parseable functionality, then a SOAP request can be implemented effectively during the development of web services (Hetland 67).
The SOAP request and response platform has several layers that are used for specifying the message formats, the transport protocols and the various strategies for message processing. It can be argued that SOAP is a more advanced XML-RPC, although it has features borrowed from WDDX. The SOAP specification framework comprises of the processing model, extensibility model, underlying protocol binding and the message construct.
The processing model of SOAP consists of the SOAP sender, which is primarily responsible for transmitting SOAP messages. The SOAP receiver serves as the destination for the SOAP messages while the passage path refers to a set of nodes that the message follows during transmission (Beazley 90).
The ultimate soap receiver denotes the final receiver of the SOAP messages. They are primarily used for processing the SOAP messages through analysis of the contents and the header information of the messages. In some cases, a SOAP intermediary is needed and serves to be the link between the SOAP sender and receiver (Drake 67).
The basic transport formats used in SOAP are the application layer protocols used in the present day internet infrastructure. SOAP uses the XML as the standard format for its messages because of its increased use in various internet applications. A drawback of the XML in the implementation of SOAP requests and responses is that if Python is implemented in it, it results into long lengths of code; therefore making code development for SOAP web services a cumbersome process (Hetland 90).
There have been criticisms concerning the effectiveness of the SOAP messages in the implementation of web services. Among its advantages is that SOAP is more extensible and flexible to be used in diverse transport protocols. Apart from usage in the standard transport protocol, the HTTP, SOAP can also be used in other transport protocols such as SMTP and JMS. Due to the fact that the SOAP model functions effectively on the HTTP transport platform, its implementation can be integrated into existing firewalls and proxies in order to enhance security of the web services during their implementation.
There are significant advantages concerning the development of web services basing on the SOAP model (Drake 170). One major disadvantage is that SOAP is significantly slower in comparison with other middle ware platforms such as COBRA. This slowness is a major issue during the sending of big SOAP messages over the web service (Beazley 78).
The slowness is due to issues associated with the XML format. The second disadvantage of the SOAP model in web service development is that roles of the various interacting users are not dynamic rather they are fixed. This implies that only a single user can have access to the services of the other party at a given time. In order to eliminate biasness during service usage, developers using the SOAP model incorporate some concept of polling in the development of web services (Drake 150).
Python language comes with SOAP libraries, making it effective in the implementation of SOAP requests and responses during the development of web services. There are diverse implementations of the SOAP model in Python programming language. The SOAP modules incorporated in Python are an integral part of the programming language during the development of web services using the SOAP model.
With the SOAP modules in its standard libraries, the development of SOAP model in Python eliminated the need to have Web Services Description Language (WSDL). The SOAP.py feature found in Python serves to support the development of Secure Sockets Layer (SSL). There are three basic approaches to development of web services in python programming language (Beazley 167). They are the Zolera Soap Infrastructure (ZSI), Soaplib and TGWebServices (TGWS). The following section provides an outline of the web services development strategies in python.
ZSI
The ZSI offers the client and server libraries that are required for effective implementation of SOAP. In order to use ZSI, a web developer drafts a WDSL file, after which one codes the source code using python and then fed to the server. The WDSL files and its data structures are transformed into classes of python language, which can be fed to the client and server during the usage of web services (Beazley 125).
Soaplib
Soaplib is used in the generation of web services basing on the WDSL files and the source code written in python language. Its drawback is that it does not use the principles of full stack solutions (Beazley 145). This implies that has to be integrated with other web frameworks in order to be used effectively in the development of web services (Hetland 124).
TGWebServices
This is a component in the Turbo-Gears library of the python language. Its significant advantage during the implementation of web services using python is that it offers controller service to the base class, making it function as a root of the web service (Beazley 189). Its functionality is similar to Soaplib in the sense that during runtime, it produces a WDSL file from the source code. In addition, the library supports JSON and XML messages on the same code. A significant concern during the use of these libraries is interoperability. TGWS is reported to have SOAP faults. Another concern is feature completeness (Hetland 134).
Conclusion
It is evident that Python language is one of the most effective programming languages used in the development of web services. The ability to implement SOAP requests and response using python is an added advantage that favors the development of web services using Python (Drake 139).
Works cited
Beazley, David. Python Essential Reference. New Jersey: Addison-Wesley, 2009.
Drake, Fred. The Python Language Reference Manual. New York: Network Theory Limited, 2003.
Hetland, Magnus Lie. Python Algorithms: Mastering Basic Algorithms in the Python Language. New York: Apress, 2010.