Using D in a CGI Environment
I usually want my programs to be able to run in a web browser, ie you navigate an address to run the program and to use the arguments for execution. For example
 | http://localhost/cgi-bin/MyDProgram?page=12345&something=else&another=keepitup |
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To do this we use the std.c.stdlib library (borrowed from C)
Some useful functions:
| static import std.c.stdlib;
static import std.string;
char[] queryString() {
return std.string.toString(std.c.stdlib.getenv("QUERY_STRING"));
} |
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This function simply retrieved the Query String (in the example: "page=12345&something=else&another=keepitup")
If you want to use it as a module, you could use the following functions to give yourself a global _GET array hash map as you have available in PHP:
| module jcgi;
// static makes the std.c.stdlib REQUIRED
static import std.c.stdlib;
static import std.string;
// global variable
char[][char[]] _GET;
// called when module is imported, initializes the hash map (_GET)
static this() {
// Output content type
jcgi.print("Content-type: text/html\n\n");
// Initialize _GET array.
_GET = jcgi.set_GET();
}
// fetch query string
char[] queryString() {
return std.string.toString(std.c.stdlib.getenv("QUERY_STRING"));
}
// assign values to _GET hash map (associative array)
char[][char[]] set_GET() {
char[][char[]] ret;
char[] q = std.string.strip(jcgi.queryString());
char[][] args = std.string.split(q, "&");
delete q;
for(int i = 0; i < args.length; i++) {
char[][] tmp = std.string.split(args[i], "=");
ret[tmp[0]] = tmp[1];
delete tmp;
}
delete args;
return ret;
} |
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If you were hoping to have some more functions that PHP does (for testing purposes or whatever), you could use the following simple ones:
| static import io = std.stdio;
void print_r(char[][char[]] arr) {
foreach(key, value; arr)
io.writefln("%s => %s", key, value);
}
void print(char[] string) {
io.writefln(string);
} |
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I am wondering if anyone has a function written that could take a string like "hello $name!" and turn it into "hello " ~ name ~ "!".
Here is some simple stuff to get you started in using your D program in a web environment.