support for deno

[hoanga]

hello,

i wanted to check if the js bindings would work using deno? the documentation mentions support for node and using bun. however, it does not mention if deno support is available.

i did attempt to try to use it from deno running on a mac aarch64 machine however got the following results:

% deno
Deno 2.2.9
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.
> import { Herb } from "npm:@herb-tools/node";
Warning The following packages contained npm lifecycle scripts (preinstall/install/postinstall) that were not executed:
┠─ npm:@herb-tools/node@0.1.0
┃
┠─ This may cause the packages to not work correctly.
┠─ Lifecycle scripts are only supported when using a `node_modules` directory.
┠─ Enable it in your deno config file:
┖─ "nodeModulesDir": "auto"
Uncaught Error: Cannot find module '/Volumes/Projects/Library/Caches/deno/npm/registry.npmjs.org/@herb-tools/node/0.1.0/build/Release/node-v108-darwin-arm64/herb.node'
Require stack:
- /Volumes/Projects/Library/Caches/deno/npm/registry.npmjs.org/@herb-tools/node/0.1.0/dist/herb-node.esm.js
    at Module._resolveFilename (node:module:619:15)
    at Module._load (node:module:497:27)
    at Module.require (node:module:681:19)
    at require (node:module:816:16)
    at file:///Volumes/Projects/Library/Caches/deno/npm/registry.npmjs.org/@herb-tools/node/0.1.0/dist/herb-node.esm.js:25:23

[marcoroth]

Hey @hoanga, thanks for opening this issue!

We are using https://github.com/mapbox/node-pre-gyp to compile the addon for Node.js. I wonder if node-pre-gyp might not be compatible with Deno.

[hoanga]

hi @marcoroth,

thanks for getting back to me. i did some more digging in and am able to get a js version of libherb to work with deno however with some caveats. the node-pre-gyp dependency might have compatibility issues with deno although the actual node-pre-gyp package itself can load in via deno (c.f. import 'npm:@mapbox/node-pre-gyp). that is an avenue that might need more exploration but i haven't looked into it myself so far.

after searching around i was able to find that deno can work with emscripten (with some effort) per this. it seems that most of the build environment settings in the wasm Makefile satisfy what is necessary for deno support however...

i had to recompile the herb wasm blob with ENVIRONMENT=shell set. see below (and have also attached diff):

% git diff
diff --git a/wasm/Makefile b/wasm/Makefile
index 421f5af..513ce9f 100644
--- a/wasm/Makefile
+++ b/wasm/Makefile
@@ -32,7 +32,7 @@ WASM_FLAGS = -s WASM=1 \
              -s EXPORT_NAME="Herb" \
              -s ALLOW_MEMORY_GROWTH=1 \
              -s ERROR_ON_UNDEFINED_SYMBOLS=0 \
-             -s ENVIRONMENT='web' \
+             -s ENVIRONMENT='shell' \
              --bind

 all: $(WASM_OUTPUT)

sample log using libherb.js compiled with ENVIRONMENT=shell

### apply above diff
### Make sure templates are generated
% bundle exec rake templates

% cd wasm

% make
[redacted]

% cd ../javascript/packages/browser/build

% ls libherb.js
libherb.js

### this was hand-generated
% cat herbloader.ts
import HerbLoader from "./libherb.js";

const herb = await HerbLoader();

export default herb;

% deno
Deno 2.2.9
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.

> import herb from   "./herbloader.ts";
./herb [command] [options]

Herb 🌿 Powerful and seamless HTML-aware ERB parsing and tooling.

./herb lex [file]      -  Lex a file
./herb lex_json [file] -  Lex a file and return the result as json.
./herb parse [file]    -  Parse a file
./herb ruby [file]     -  Extract Ruby from a file
./herb html [file]     -  Extract HTML from a file
./herb prism [file]    -  Extract Ruby from a file and parse the Ruby source with Prism
undefined

> var sample_source = '<p>Hello <%= user.name %></p>'
undefined

> herb.parse(sample_source)
{
  value: {
    type: "AST_DOCUMENT_NODE",
    location: { start: { line: 1, column: 0 }, end: { line: 1, column: 29 } },
    errors: [],
    children: [
      {
        type: "AST_HTML_ELEMENT_NODE",
        location: { start: [Object], end: [Object] },
        errors: [],
        open_tag: {
          type: "AST_HTML_OPEN_TAG_NODE",
          location: [Object],
          errors: [],
          tag_opening: [Object],
          tag_name: [Object],
          tag_closing: [Object],
          children: null,
          is_void: false
        },
        tag_name: {
          value: "p",
          type: "TOKEN_IDENTIFIER",
          range: [Array],
          location: [Object]
        },
        body: [ [Object], [Object] ],
        close_tag: {
          type: "AST_HTML_CLOSE_TAG_NODE",
          location: [Object],
          errors: [],
          tag_opening: [Object],
          tag_name: [Object],
          tag_closing: [Object]
        },
        is_void: false
      }
    ]
  },
  source: "<p>Hello <%= user.name %></p>",
  warnings: [],
  errors: []
}

i am also attaching compiled versions of libherb.js in an archive (suffixed -web, -node, -shell, appropriately) that i was able to build (using tag v0.1.1) that i checked to see which versions work with deno. i could only get the shell version of libherb.js to load with deno but perhaps i am missing something else in a tweak. i am not sure what the best or preferred path for getting deno support into herb (eg. should deno be able to handle this? does herb have to handle it?) would be but herb can work with deno (with some effort).

libherb.zip

[hoanga]

wasm-env.patch

[marcoroth]

Thank you so much for exploring this @hoanga, this looks promising!

Personally I don't see a need to support Deno, but I'm curious to hear your use-case for Deno. Were you just curious or is there a reason why we'd want to specifically build an integration for Deno?

The Node.js package was mostly motivated by the use of Node.js in VSCode and the way Stimulus LSP works and runs.

The other route to explore would be to see if we can run the WASM build in Node.js too. So that we have two WASM builds (one for web and one for shell). Then the web build would work for the @herb-tools/browser package and the shell build could work for the @herb-tools/node and a potential new @herb-tools/deno package.

[hoanga]

hi @marcoroth, i have been trying to use deno as a replacement for node.js when dealing with (web) frontend matters. so i guess this would be classified more as a curiosity than an actual need. since deno has been moving towards adding more node.js compatibility with each successive version, it is still not clear to me if the current inability to use the node.js package of herb would be considered an issue directly for the deno folks or elsewhere (ex. node-pre-gyp).

i appreciate that you would consider adding deno support via wasm builds which would be a more immediate answer although understand if you would rather not as that would add an extra maintenance burden for something that at some point in the future might not be needed (ex. deno's node.js compatibility improves to the point where a separate build is not needed)

[marcoroth]

Looks like it just works fine with the current node-wasm package. I opened #1296 to test and assure Deno-compatibility in CI.