feat(wasm): clawhdf5-wasm, the reader for JavaScript via wasm-bindgen

open(bytes) -> H5File with kind/list/info/attrs/attrErrors/read/
readHyperslab. Numeric data comes back in the typed array of the
stored width (Int16Array for i16, BigInt64Array for i64, Float32Array
for f32/f16, ...), strings and enum names as string arrays, array
datatypes flattened with their dims appended to the shape. Compound,
reference, opaque and VL-sequence datasets are refused with an error
naming the type; nothing is returned as reinterpreted bytes.

The logic is in a plain-Rust core module, tested natively: unit tests,
and h5py_interop, which compares every dataset, hyperslab, listing and
attribute of an h5py- and a netCDF4-written file with what libhdf5
reads back (generator shared with the Node test of the built package).

No mmap, no threads; lz4 is on, zstd/szip (C) are not. A
wasm-release profile (opt-level s, LTO) serves the browser build.
ci-test.sh lints the crate for wasm32 and checks it builds no C.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
This commit is contained in:
osobh
2026-09-26 00:00:46 -05:00
co-authored by Claude Opus 5.5
parent 74f9f50086
commit a42b646689
9 changed files with 1337 additions and 5 deletions
+9 -2
View File
@@ -92,7 +92,8 @@ run_step "cargo clippy (fast-deflate / zlib-ng)" cargo clippy \
no_c_in_default_build() {
local crate found=0
for crate in clawhdf5-format clawhdf5-io clawhdf5-filters clawhdf5 \
clawhdf5-agent clawhdf5-ann clawhdf5-accel clawhdf5-netcdf4 clawhdf5-cli; do
clawhdf5-agent clawhdf5-ann clawhdf5-accel clawhdf5-netcdf4 clawhdf5-cli \
clawhdf5-wasm; do
local c_deps
c_deps=$(cargo tree -q -p "$crate" -e normal,build --prefix none \
| grep -E '^([a-z0-9_-]+-sys|cc|cmake) v' | sort -u)
@@ -107,12 +108,18 @@ no_c_in_default_build() {
run_step "no C in the default build (core crates)" no_c_in_default_build
# The reader in the browser: the facade's read path must build for
# wasm32-unknown-unknown (no mmap, no threads, no file system). Needs
# wasm32-unknown-unknown (no mmap, no threads, no file system), and the
# wasm-bindgen crate must build and lint there. Needs
# `rustup target add wasm32-unknown-unknown`.
run_step "wasm32 build (clawhdf5, no default features)" cargo build \
-p clawhdf5 \
--target wasm32-unknown-unknown \
--no-default-features
run_step "wasm32 clippy (clawhdf5-wasm)" cargo clippy \
-p clawhdf5-wasm \
--target wasm32-unknown-unknown \
--all-targets \
-- -D warnings
# The workspace declares a minimum Rust version (rust-version in Cargo.toml);
# check that it really builds there, so the README badge and the manifests