Hello world/Web server: Difference between revisions

{{task|Networking and Web Interaction}}

The browser is the new [[GUI]]!

The task is to serve our standard text "Goodbye, World!" to http://localhost:8080/ so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested.

Note that starting a web browser or opening a new window with this URL is not part of the task. Additionally, it is permissible to serve the provided page as a plain text file (there is no requirement to serve properly formatted [[HTML]] here). The browser will generally do the right thing with simple text like this.

With GNU AWK (gawk) a simple web server can be implemented. The example is taken from here

Using sockets only, also shows use of heredoc syntax, std.array.replace, and casting to bool to satisfy the while conditional.

Using builtin HTTP server with call back to do/1. It only lasts 30 seconds (30000 milliseconds), then it is stopped. I fail to see how a longer time will serve any purpose.

Lightweightly concurrent "hello world" web server using the [http://www.yesodweb.com/book/conduits conduit] stack:

If the desire is to use the browser as a gui, the easiest thing to do would be to [http://www.jsoftware.com/stable.htm download] [http://www.jsoftware.com/docs/help701/user/relhigh.htm j7], edit the jhs script to start on port 8080, start jhs, visit http://127.0.0.1:8080/jijx then enter the text:

This will compute the desired result and display it (actually, it will be displayed twice since the original string will also be displayed). This would be even simpler if you could just use the default jhs port (65001)... Alternatively, a jhs form could be used (but this would not have the exact url structure specified).

However, if the desire is to implement the task exactly, any of approaches at [[j:JWebServer]] might be used.

For example, here is a web server which ignores the client's request and always returns Goodbye, World:

This version works because reasonable http requests fit in a single tcp packet. (And note that the server waits for one tcp packet before responding.) If parsing of the request is desired, one of the more complicated implementations at [[j:JWebServer]] should be used instead (but that's not really relevant for this task, except perhaps to require complete headers before responding, with broken browsers which send multiple tcp packets for the request).

Multiple requests will be served in the order that they reach the server, with a queue size limit of 50 waiting requests imposed by default in the <code>ServerSocket</code> class (may be changed by adding a second positive integer argument to the <code>ServerSocket</code> constructor).

While Lasso has a built-in webserver you can use, here's how you can create a basic multi-threaded webserver of your own to complete this request:

This is difficult, although possible, in Liberty BASIC, but it's close relative Run BASIC is designed for serving webpages easily. The task becomes simply ..

Various modules exist for using sockets, including the popular IO::Socket which provides a simpler and more friendly OO interface for the socket layer. Here is the solution using this module:

Using Perl's glue power, provide a suicide note with visitor counter via netcat:

[[Category:Scala Implementations]]

Be aware that the above is an ad-hoc minimal scripting example. Normally, a service subclass is used and response handlers are defined as methods of it (not as action blocks).

Also, services and HTML generation is usually done using a framework (at least DOM-based, but usually a higher level toolkit).

Pharo ships with the Zinc HTTP Component frameworks that includes a ZnServer class. Here's the simplest solution to start a web server:

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