wasm.ts•2.18 kB
import { PluginBuild } from "esbuild";
import path from "path";
// TODO wasm contents aren't watched
// eslint-disable-next-line no-restricted-imports
import fs from "fs";
export const wasmPlugin = {
name: "convex-wasm",
setup(build: PluginBuild) {
// Resolve ".wasm" files to a path with a namespace
build.onResolve({ filter: /\.wasm$/ }, (args) => {
// If this is the import inside the stub module, import the
// binary itself. Put the path in the "wasm-binary" namespace
// to tell our binary load callback to load the binary file.
if (args.namespace === "wasm-stub") {
return {
path: args.path,
namespace: "wasm-binary",
};
}
// Otherwise, generate the JavaScript stub module for this
// ".wasm" file. Put it in the "wasm-stub" namespace to tell
// our stub load callback to fill it with JavaScript.
//
// Resolve relative paths to absolute paths here since this
// resolve callback is given "resolveDir", the directory to
// resolve imports against.
if (args.resolveDir === "") {
return; // Ignore unresolvable paths
}
return {
path: path.isAbsolute(args.path)
? args.path
: path.join(args.resolveDir, args.path),
namespace: "wasm-stub",
};
});
// Virtual modules in the "wasm-stub" namespace are filled with
// the JavaScript code for compiling the WebAssembly binary. The
// binary itself is imported from a second virtual module.
build.onLoad({ filter: /.*/, namespace: "wasm-stub" }, async (args) => ({
contents: `import wasm from ${JSON.stringify(args.path)}
export default new WebAssembly.Module(wasm)`,
}));
// Virtual modules in the "wasm-binary" namespace contain the
// actual bytes of the WebAssembly file. This uses esbuild's
// built-in "binary" loader instead of manually embedding the
// binary data inside JavaScript code ourselves.
build.onLoad({ filter: /.*/, namespace: "wasm-binary" }, async (args) => ({
contents: await fs.promises.readFile(args.path),
loader: "binary",
}));
},
};