Offer CDN for WASM JavaScript

[ed-henrique]

Is your feature request related to a problem? Please describe.
I found it difficult to setup WASM from the docs, and in the end, I had to install Node.js and use it (adding yet another dependency to my project). I found this CDN, but I don't know if it's oficially maintained by you guys (Also, it doesn't work).

Describe the solution you'd like to see
I would like to see a way to use Themis from the browser without the need for Node.js.

Describe alternatives you've considered

• Offer a single minified file for the libthemis.js (Containing all cryptosystems and key generation), bundled with libthemis.wasm;

Additional context
I'm not very familiar with WASM, so I don't know the feasibility of loading it from a CDN (Even more so in a security-focused project like this one). If there are any easier ways to set this up, please let me know.

[ed-henrique]

On a side note, I could make this work by doing this:

1. Download all of the files from the dist-es6directory from the CDN (Check the script below);

for f in context.js index.js libthemis.js libthemis.wasm secure_cell_context_imprint.js secure_cell_seal.js secure_cell_token_protect.js secure_comparator.js secure_keygen.js secure_message.js secure_session.js themis_error.js utils.js; do curl -o $f https://cdn.jsdelivr.net/npm/wasm-themis@latest/dist-es6/$f; done

2. Execute the script below;

# Adds .js extension to all of the imports
find . -name "*.js" ! -name "libthemis.js" -exec sed -i "s/\(import.*from[[:space:]]\+['\"]\)\([^'\"]*\)\(['\"]\)/\1\2.js\3/" {} +
 
# Removes extra .js from libthemis.js import in index.js
sed -i 's/libthemis\.js\.js/libthemis\.js/g' index.js
 
# Adds default export to Module in libthemis.js
printf "\n\nexport default Module;" >> libthemis.js
 
# Removes module.exports from libthemis.js
sed -i 's/module\.exports=Module;//' libthemis.js

This way, I was able to initialize themis and use it as expected.

Example

<script type="module">
  import themis from "/index.js"; // Loading from a local file server

  async function main() {
    await themis.initialized;
    
    let keypair = new themis.KeyPair();
  
    let privateKey = keypair.privateKey;
    let publicKey = keypair.publicKey;
    
    console.log("Working 😎");
  }
  
  main();
</script>

Needless to say that this is kinda of a burden. It would be easier to add .js extensions by default, add a conditional to check if module exists before module.exports=Module; and check if in a ES6 environment to add export default Module;.