mrml python 以及webassembly 实现简单说明

简单说明下mrml python 以及webassembly 的实现

python

python 是基于了pyo3，利用pyo3 提供的能力，暴露了python 模块

• 参考处理

// 暴露的mrml 模块

#[pymodule]

#[pyo3(name = "mrml")]

fn register(_py: Python<'_>, m: &PyModule) -> PyResult<()> {

    // mrml 方法的注册

    m.add_class::<NoopIncludeLoaderOptions>()?;

    m.add_class::<MemoryIncludeLoaderOptions>()?;

    m.add_class::<ParserOptions>()?;

    m.add_class::<RenderOptions>()?;

    m.add_function(wrap_pyfunction!(to_html, m)?)?;

    m.add_function(wrap_pyfunction!(noop_loader, m)?)?;

    m.add_function(wrap_pyfunction!(memory_loader, m)?)?;

    Ok(())

}

• 基于maturinpip 的包构建
  基于了pyo3 提供的maturin 做为pip 的backend
  pyproject.toml

[build-system]

requires = ["maturin>=1,<2"]

build-backend = "maturin"

 

[project]

name = "mrml"

description = "A Python wrapper for MRML (Rust port of MJML)."

readme = "readme.md"

requires-python = ">=3.7"

classifiers = [

  "Programming Language :: Rust",

  "Programming Language :: Python :: Implementation :: CPython",

  "Programming Language :: Python :: Implementation :: PyPy",

]

 

[project.urls]

"Homepage" = "https://github.com/jdrouet/mrml"

"Bug Tracker" = "https://github.com/jdrouet/mrml/issues"

webassembly

webassembly 的构建使用了 wasm-bindgen，暴露了Engine 以及一些操作方法

• 部分参考代码

#[derive(Debug, Default)]

#[wasm_bindgen]

pub struct Engine {

    parser: Rc<mrml::prelude::parser::ParserOptions>,

    #[cfg(feature = "async")]

    async_parser: Rc<mrml::prelude::parser::AsyncParserOptions>,

    render: mrml::prelude::render::RenderOptions,

}

 

#[wasm_bindgen]

impl Engine {

    #[wasm_bindgen(constructor)]

    pub fn new() -> Self {

        Self::default()

    }

 

    /// Defines the parsing options.

    #[allow(clippy::arc_with_non_send_sync)]

    #[wasm_bindgen(js_name = "setParserOptions")]

    pub fn set_parser_options(&mut self, value: ParserOptions) {

        self.parser = Rc::new(value.into());

    }

 

    /// Defines the async parsing options.

    #[cfg(feature = "async")]

    #[allow(clippy::arc_with_non_send_sync)]

    #[wasm_bindgen(js_name = "setAsyncParserOptions")]

    pub fn set_async_parser_options(&mut self, value: AsyncParserOptions) {

        self.async_parser = Rc::new(value.into());

    }

 

    /// Defines the rendering options.

    #[wasm_bindgen(js_name = "setRenderOptions")]

    pub fn set_render_options(&mut self, value: RenderOptions) {

        self.render = value.into();

    }

 

    /// Renders the mjml input into html.

    #[wasm_bindgen(js_name = "toHtml")]

    pub fn to_html(&self, input: &str) -> ToHtmlResult {

        match to_html(input, &self.parser, &self.render) {

            Ok(content) => ToHtmlResult::Success { content },

            Err(error) => ToHtmlResult::Error(error),

        }

    }

• webassembly 的构建
  基于了wasm-pack
  参考命令

wasm-pack build --target nodejs --release

说明

mrml 对于python 以及webassembly 的支持都是基于了rust 的周边能力，集成起来还是比较方便的，对于mrml 构建相关的可以看看
github 代码中的github action workflow 配置

参考资料

https://github.com/jdrouet/mrml
https://pyo3.rs/
https://github.com/PyO3/pyo3
https://github.com/rustwasm/wasm-pack
https://rustwasm.github.io/wasm-pack/