Web Server Programming phần 1 ppsx

[...]... standards for web server to application communications made it practical to have web- based clients that could submit data for processing by server applications hosted on the web server These extensions made business-to-consumer web commerce practical All consumers could be assumed to have standard web browsers; links between browsers and web servers could be made fairly secure; and web servers had standardized... of hypertext reports The HTML/HTTP scheme was presented at various conferences in 19 91, and the web began its worldwide growth By early 19 93, there were around fifty HTTP web servers on the Internet, and there were about 10 0 Mbyte per month of HTML network traffic In the early days, many different web browsers and web servers competed for adoption Most incorporated various idiosyncratic features that... http://www.dontdeliverpizzas.com/order.cgi HTTP /1. 1 Forms and CGI 15 USER-AGENT: ACCEPT: text/plain, text/html Various other header fields as per HTTP /1. 1 specification, then a blank line p_size=fam&tops=Cheese&tops=Sun+dried+tomatoes&xtra=Coke&customer= Smith& The web server that receives such a request has to recognize it as a command to run a program, rather than an attempt to retrieve a file A typical web server is configured... data A web server uses this feature to add data to the default environment, data that describe the web server, the current client and the client’s request The CGI specification defined the data that were to be transferred through environment variables Some relate to the web server itself; for example: G SERVER_ SOFTWARE This should identify the server (e.g Apache, IIS) and its version number G SERVER_ PORT... The major servers of the time would have included the file transfer (ftp) server, the telnet server that supported remote log in, mail and news servers, and utility programs such as echo These servers all involve active clients initiating contact with passive servers In most cases, the servers are always running as background daemon processes on the machine that is hosting them; the typical server daemon... browser and server available from early 19 95 The SSL is just an extra layer in the protocol stack, coming between the TCP network protocol and the HTTP application protocol levels With SSL-aware browsers and web servers, there is an extra step taken after a TCP connection is established and before the web server program starts to read client requests This extra step involves the browser and web server programs... Apache web server started as a ‘patched’ version of the NCSA server) By late 19 93, there were 8 Introduction more than 600 web servers on the Internet and HTML traffic had grown to 200,000 Mbyte per month Business interest in the WWW was sparked by reports appearing in the New York Times and The Economist Of course, additions like support for images necessitated extensions to the HTTP protocol If a server. .. alternative technology to servlets/JSPs/EJBs for large-scale web applications At a different level, NET offers a totally new and really rather more coherent model for the relation between browser client and web server components.) Chapter 11 : Future technologies? This chapter covers a recent success story for web support services (Akamai's ‘Edge’ servers), some speculations on other areas such as peer-topeer... separate server process for each concurrent client Where a threaded server simply creates a new thread in the server process to handle a new client, a ‘forking’ server creates a new process (the system call to create a new child process is called fork on Unix, hence the naming ‘forking server ) The following pseudo-code provides a crude outline for such a server: Main() Create a socket ( "server socket")... very brief overview of both HTML page layout coding and client-side JavaScript) 1. 1 Servers on the Internet Client server systems have been operating across networks since the early days of the ARPANET back in the late 19 60s The mechanisms that are used became more or less standardized in the early 19 80s Most of the client server systems would then have run on variants of the Unix operating system Network . features 13 1 5 .12 Perl and the OS 13 6 5 .12 .1 Manipulating files and directories 13 7 5 .12 .2 Perl: processes 14 0 5 .12 .3 A ‘systems programming example 14 3 5 .13 Networking 15 0 5 .14 Modules 15 3 5 .15 Databases. Databases 15 4 5 .15 .1 Basics 15 4 vi Contents 5 .15 .2 Database example 15 8 5 .16 Perl: CGI 16 3 5 .16 .1 ’Roll your own’ CGI code 16 4 5 .16 .2 Perl: CGI module(s) 17 1 5 .16 .3 Security issues and CGI 17 3 Exercises. Enterprise Java 435 10 .1 EJB background 437 10 .1. 1 Smart beans in s marter containers 437 10 .1. 2 Distributed objects 438 10 .2 EJB basics 4 41 10.2 .1 Servers, containers and beans 4 41 10.2.2 The life