HtmlToPdf provides an easy-to-use interface for concurrently printing HTML to PDF on iOS and macOS.
- Convert HTML strings to PDF documents on both iOS and macOS.
- Lightweight and fast: it can handle thousands of documents quickly.
- Customize margins for PDF documents.
- Swift 6 language mode enabled
- And one more thing: easily print images in your PDFs!
Print to a file url:
try await "<html><body><h1>Hello, World 1!</h1></body></html>".print(to: URL(...))Print to a directory with a file title.
let directory = URL(...)
let html = "<html><body><h1>Hello, World 1!</h1></body></html>"
try await html.print(title: "file title", to: directory)Print a collection to a directory.
let directory = URL(...)
try await [
html,
html,
html,
....
]
.print(to: directory)The package includes a test that prints 1000 HTML strings to PDFs in ~2.6 seconds (using UIPrintPageRenderer on iOS or Mac Catalyst) or ~12 seconds (using NSPrintOperation on MacOS).
@Test func collection() async throws {
[...]
let count = 1_000
try await [String].init(
repeating: "<html><body><h1>Hello, World 1!</h1></body></html>",
count: count
)
.print(to: URL(...))
[...]
}Optionally, you can invoke an overload that returns an AsyncStream<URL> that yields the URL of each printed PDF.
Note
You need to include the AsyncStream type signature in the variable declaration, otherwise the return value will be Void.
let directory = URL(...)
let urls: AsyncStream = try await [
html,
html,
html,
....
]
.print(to: directory)
for await url in urls {
Swift.print(url)
}HtmlToPdf supports base64-encoded images out of the box.
Important
You are responsible for encoding your images to base64.
The example below will correctly render the image in the HTML, assuming the [...] is replaced with a valid base64-encoded string.
"<html><body><h1>Hello, World 1!</h1><img src="data:image/png;charset=utf-8;base64, [...]" alt="imageDescription"></body></html>"
.print(to: URL(...))
Tip
You can use swift to load the image from a relative or absolute path and then convert them to base64. Here's how you can achieve this using the convenience initializer on Image using coenttb/swift-html:
struct Example: HTML {
var body: some HTML {
[...]
if let image = Image(base64EncodedFromURL: "path/to/your/image.jpg", description: "Description of the image") {
image
}
[...]
}
}
Click here for the implementation of Image.init(base64EncodedFromURL:), which shows how to encode an image to base64.
To install the package, add the following line to your Package.swift file:
dependencies: [
.package(url: "https://github.com/coenttb/swift-html-to-pdf.git", from: "0.1.0")
]You can then make HtmlToPdf available to your Package's target by including HtmlToPdf in your target's dependencies as follows:
targets: [
.target(
name: "TheNameOfYourTarget",
dependencies: [
.product(name: "HtmlToPdf", package: "swift-html-to-pdf")
]
)
]