libxml2-wasm

libxml2-wasm

Disclaimer

Current version is for feasibility/performance evaluation only

The api may have breaking changes in patch versions.

Why another xml lib?

Compiling C library libxml2 to WebAssembly brings benefits of both pure javascript implementation or native addons, and avoided their drawbacks:

• Good performance: the string api has a comparable performance to the native addons, and much better than pure javascript implementations; the buffer api(no string conversion) has an impressive performance in the benchmark.
• Better compatibility: don't need to compile to every platform, nodeJs version, or dependency libraries(e.g. glibc); and supports browsers too.
• Comprehensive functionality(To be finished): backed by libxml2, we just need some wrappers being callable by javascript.

Documentation

https://jameslan.github.io/libxml2-wasm/index.html

Supported Environments

This library uses ES Module and top level await, so it require the following environment.

Environment	Version
NodeJs	v14.8+
Chrome	V89+
Edge	V89+
Safari	v15+

Benchmark

To run the benchmark, build the lib first,

npm ci && npm run build

Then run test in benchmark directory,

cd benchmark && npm ci
npm test

libxmljs2 is js binding to native library libxml2; while fast-xml and xmldoc are pure javascript implementations.

Environment: NodeJs v18.17.1 on Darwin x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz

Running "fixtures/small.xml: 787 bytes" suite...
Progress: 100%

  libxml2-wasm:
    64 645 ops/s, ±1.22%    | 44.35% slower

  libxml2-wasm(buffer api):
    116 157 ops/s, ±0.67%   | fastest

  libxmljs2:
    28 240 ops/s, ±9.20%    | 75.69% slower

  fast-xml-parser:
    18 091 ops/s, ±7.90%    | 84.43% slower

  xmldoc:
    14 310 ops/s, ±1.88%    | slowest, 87.68% slower

Running "fixtures/medium.xml: 35562 bytes" suite...
Progress: 100%

  libxml2-wasm:
    2 706 ops/s, ±0.79%    | 73.57% slower

  libxml2-wasm(buffer api):
    10 237 ops/s, ±0.48%   | fastest

  libxmljs2:
    4 779 ops/s, ±8.57%    | 53.32% slower

  fast-xml-parser:
    995 ops/s, ±2.09%      | 90.28% slower

  xmldoc:
    844 ops/s, ±1.33%      | slowest, 91.76% slower

Running "fixtures/large.xml: 2337522 bytes" suite...
Progress: 100%

  libxml2-wasm:
    22 ops/s, ±1.29%   | 37.14% slower

  libxml2-wasm(buffer api):
    35 ops/s, ±0.88%   | fastest

  libxmljs2:
    21 ops/s, ±14.92%   | 40% slower

  fast-xml-parser:
    6 ops/s, ±5.99%    | 82.86% slower

  xmldoc:
    4 ops/s, ±3.67%    | slowest, 88.57% slower