improved wasm build process (#933)

Co-authored-by: Victor Moreno <[email protected]>

Author: Swolebrain

cedar-wasm/README.md

@@ -4,8 +4,7 @@ An implementation of various cedar functions to enable developers to write types
 
 ## Installing
 
-Installing is simple, just run `npm i @cedar-policy/cedar-wasm` or install with whatever your favorite package manager is.
-
+Installing is simple, just run `npm i @cedar-policy/cedar-wasm --save` or install with whatever your favorite package manager is.
 
 ## Loading in webpack 5:
 
@@ -133,3 +132,20 @@ import('@cedar-policy/cedar-wasm').then(mod => {
 });
 ```
 
+## Alternate loading strategies
+
+If for some reason you cannot use es modules, we provide alternate sub-packages `web` and `nodejs` (defined as `exports` in the root package.json).
+
+The `nodejs` subpackage uses `fs` and CommonJS modules. To use it, you can import it like so:
+
+```
+const cedar = require('@cedar-policy/cedar-wasm/nodejs')
+```
+
+The `web` subpackage exposes an `initSync` function that you can use to load Cedar in scenarios where you want to load the wasm binary async for whatever reason. Using the `web` subpackage may also be necessary with some `jest` setups. Here's how you use the `web` subpackage:
+
+```
+const wasmBuffer = ... // `fetch` it or use `fs` to read it from `node_modules` in jest setupTests
+import * as cedarJsBindings from '@cedar-policy/cedar-wasm/web';
+cedarJsBindings.initSync(wasmBuffer);
+```

cedar-wasm/build-wasm.sh

@@ -14,30 +14,67 @@
 # limitations under the License.
 
 # This script calls wasm-pack build and post-processes the generated TS types to fix them.
+# It also produces three sets of outputs for different needs of different consumers
 # Without this, the built wasm still works, but the Typescript definitions made by tsify don't.
 set -e
-cargo build
-wasm-pack build --scope cedar-policy --target bundler
-
-sed -i "s/[{]\s*!: /{ \"!\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*==: /{ \"==\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*!=: /{ \"!=\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*<: /{ \"<\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*<=: /{ \"<=\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*>: /{ \">\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*>=: /{ \">=\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*&&: /{ \"\&\&\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*||: /{ \"||\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*[+]: /{ \"+\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*-: /{ \"-\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*[*]: /{ \"*\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/[{]\s*\.: /{ \".\": /g" pkg/cedar_wasm.d.ts
-sed -i "s/ | __skip//g" pkg/cedar_wasm.d.ts
-sed -i "s/SchemaFragment/Schema/g" pkg/cedar_wasm.d.ts
-
-echo "type SmolStr = string;" >> pkg/cedar_wasm.d.ts
-echo "type Name = string;" >> pkg/cedar_wasm.d.ts
-echo "type Id = string;" >> pkg/cedar_wasm.d.ts
-echo "export type TypeOfAttribute = SchemaType & { required?: boolean };" >> pkg/cedar_wasm.d.ts
-echo "export type Context = Record<string, CedarValueJson>;" >> pkg/cedar_wasm.d.ts
-echo "Finished post-processing types file"
+main () {
+    rm -rf pkg || true
+    mkdir pkg
+    cargo build
+    wasm-pack build --scope cedar-policy --target bundler --out-dir pkg/esm
+    wasm-pack build --scope cedar-policy --target nodejs  --out-dir pkg/nodejs
+    wasm-pack build --scope cedar-policy --target web  --out-dir pkg/web
+    cp pkg/esm/README.md pkg/README.md
+
+    fix_package_json_files 
+
+    process_types_file "pkg/esm/cedar_wasm.d.ts"
+    process_types_file "pkg/nodejs/cedar_wasm.d.ts"
+    process_types_file "pkg/web/cedar_wasm.d.ts"
+}
+
+fix_package_json_files() {
+    jq -s '.[0] * .[1]' pkg/esm/package.json package.json.patch > pkg/package.json
+    echo "Created root package.json"
+    mv pkg/esm/package.json pkg/esm/package.json.bak
+    mv pkg/web/package.json pkg/web/package.json.bak
+    mv pkg/nodejs/package.json pkg/nodejs/package.json.bak
+    jq '. + {"type": "module"}' pkg/esm/package.json.bak > pkg/esm/package.json
+    jq '. + {"type": "module"}' pkg/web/package.json.bak > pkg/web/package.json
+    jq '. + {"type": "commonjs"}' pkg/nodejs/package.json.bak > pkg/nodejs/package.json
+    rm pkg/esm/package.json.bak
+    rm pkg/web/package.json.bak
+    rm pkg/nodejs/package.json.bak
+    echo "Patched sub-package json files"
+}
+
+process_types_file() {
+    local types_file="$1"
+    echo "processing types file: $1"
+    sed -i "s/[{]\s*!: /{ \"!\": /g" "$types_file"
+    sed -i "s/[{]\s*==: /{ \"==\": /g" "$types_file"
+    sed -i "s/[{]\s*!=: /{ \"!=\": /g" "$types_file"
+    sed -i "s/[{]\s*<: /{ \"<\": /g" "$types_file"
+    sed -i "s/[{]\s*<=: /{ \"<=\": /g" "$types_file"
+    sed -i "s/[{]\s*>: /{ \">\": /g" "$types_file"
+    sed -i "s/[{]\s*>=: /{ \">=\": /g" "$types_file"
+    sed -i "s/[{]\s*&&: /{ \"\&\&\": /g" "$types_file"
+    sed -i "s/[{]\s*||: /{ \"||\": /g" "$types_file"
+    sed -i "s/[{]\s*[+]: /{ \"+\": /g" "$types_file"
+    sed -i "s/[{]\s*-: /{ \"-\": /g" "$types_file"
+    sed -i "s/[{]\s*[*]: /{ \"*\": /g" "$types_file"
+    sed -i "s/[{]\s*\.: /{ \".\": /g" "$types_file"
+    sed -i "s/ | __skip//g" "$types_file"
+    sed -i "s/SchemaFragment/SchemaJson/g" "$types_file"
+    sed -i "s/[{] json: JsonValueWithNoDuplicateKeys /{ json: SchemaJson /g" "$types_file"
+
+    echo "type SmolStr = string;" >> "$types_file"
+    echo "type Name = string;" >> "$types_file"
+    echo "type Id = string;" >> "$types_file"
+    echo "export type TypeOfAttribute = SchemaType & { required?: boolean };" >> "$types_file"
+    echo "export type Context = Record<string, CedarValueJson>;" >> "$types_file"
+}
+
+
+main
+echo "Finished custom build script"

cedar-wasm/package.json.patch

@@ -0,0 +1,20 @@
+{
+  "files": ["esm/*", "nodejs/*", "web/*"],
+  "sideEffects": ["./snippets/*"],
+  "module": "esm/cedar_wasm.js",
+  "types": "esm/cedar_wasm.d.ts",
+  "exports": {
+    ".": {
+      "import": "esm/cedar_wasm.js",
+      "types": "esm/cedar_wasm.d.ts"
+    },
+    "./nodejs": {
+      "import": "nodejs/cedar_wasm.js",
+      "types": "nodejs/cedar_wasm.d.ts"
+    },
+    "./web": {
+      "import": "web/cedar_wasm.js",
+      "types": "web/cedar_wasm.d.ts"
+    }
+  }
+}