Given a CSS file, we want to replace all instances of a particular image URL with a data URI to reduce the number of requests. Let's write a small D program to do this replacement.
Let's create a data URI by executing the following steps:
Load the image file with
std.file.read().Create the data URI with
std.base64as shown in the following code:pure char[] makeDataUri(string contentType, in void[] data) { import std.base64; return "data:" ~ contentType ~ ";base64," ~ Base64.encode(cast(const(ubyte[]))) data; }Load the CSS file with
std.file.readText.Use
std.array.replaceto replace the URL with the data URI.Save the CSS file with
std.file.write.
Putting it all together in main, you will have the following code:
void main() {
import std.file, std.array;
auto imageData = std.file.read("image.png"); // step 1
string dataUri = makeDataUri("image/png", imageData);
// step 2
auto cssFile = std.file.readText("style.css"); ...