feat: Polars build for Pyodide (#20383)

Co-authored-by: ritchie <[email protected]>

.github/workflows/release-python.yml

@@ -304,6 +304,70 @@ jobs:
           name: wheel-${{ matrix.package }}-${{ matrix.os }}-${{ matrix.architecture }}
           path: dist/*.whl
 
+  build-wheel-pyodide:
+    name: build-wheels (polars, pyodide, wasm32)
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.sha }}
+
+      # Avoid potential out-of-memory errors
+      - name: Set swap space for Linux
+        uses: pierotofy/set-swap-space@master
+        with:
+          swap-size-gb: 10
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ env.PYTHON_VERSION }}
+
+      - name: Disable incompatible features
+        env:
+            FEATURES: parquet|async|json|extract_jsonpath|cloud|polars_cloud|tokio|clipboard|decompress|new_streaming
+        run: |
+          sed -i 's/^  "json",$/  "serde_json",/' crates/polars-python/Cargo.toml
+          sed -E -i "/^  \"(${FEATURES})\",$/d" crates/polars-python/Cargo.toml py-polars/Cargo.toml
+
+      - name: Setup emsdk
+        uses: mymindstorm/setup-emsdk@v14
+        with:
+          # This should match the exact version of Emscripten used by Pyodide
+          version: 3.1.58
+
+      - name: Install LLVM
+        # This should match the major version of LLVM expected by Emscripten
+        run: |
+          wget https://apt.llvm.org/llvm.sh
+          chmod +x llvm.sh
+          sudo ./llvm.sh 19
+          echo "EM_LLVM_ROOT=/usr/lib/llvm-19/bin" >> $GITHUB_ENV
+
+      - name: Set CFLAGS and RUSTFLAGS for wasm32
+        run: |
+            echo "CFLAGS=-fPIC" >> $GITHUB_ENV
+            echo "RUSTFLAGS=-C link-self-contained=no" >> $GITHUB_ENV
+
+      - name: Build wheel
+        uses: PyO3/maturin-action@v1
+        with:
+          command: build
+          target: wasm32-unknown-emscripten
+          args: >
+            --profile dist-release
+            --manifest-path py-polars/Cargo.toml
+            --interpreter python3.10
+            --out wasm-dist
+          maturin-version: 1.7.4
+
+      - name: Upload wheel
+        uses: actions/upload-artifact@v4
+        with:
+          name: wheel-polars-emscripten-wasm32
+          path: wasm-dist/*.whl
+
   publish-to-pypi:
     needs: [create-sdist, build-wheels]
     environment:
@@ -327,7 +391,7 @@ jobs:
           verbose: true
 
   publish-to-github:
-    needs: publish-to-pypi
+    needs: [publish-to-pypi, build-wheel-pyodide]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -340,6 +404,12 @@ jobs:
           name: sdist-polars
           path: dist
 
+      - name: Download Pyodide wheel
+        uses: actions/download-artifact@v4
+        with:
+          name: wheel-polars-emscripten-wasm32
+          path: wasm-dist
+
       - name: Get version from Cargo.toml
         id: version
         working-directory: py-polars
@@ -372,7 +442,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           TAG: ${{ steps.github-release.outputs.tag_name }}
-          FILES: dist/polars-*.tar.gz
+          FILES: dist/polars-*.tar.gz wasm-dist/polars-*.whl
 
       - name: Publish GitHub release
         if: inputs.dry-run == false

.github/workflows/test-pyodide.yml

@@ -0,0 +1,70 @@
+name: Test Pyodide
+
+on:
+  pull_request:
+    paths:
+      - Cargo.lock
+      - py-polars/**
+      - docs/source/src/python/**
+      - crates/**
+      - .github/workflows/test-pyodide.yml
+  push:
+    branches:
+      - main
+    paths:
+      - Cargo.lock
+      - crates/**
+      - docs/source/src/python/**
+      - py-polars/**
+      - .github/workflows/test-pyodide.yml
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  RUSTFLAGS: -C link-self-contained=no -C debuginfo=0
+  CFLAGS: -fPIC
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  test-pyodide:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Disable incompatible features
+        env:
+            FEATURES: parquet|async|json|extract_jsonpath|cloud|polars_cloud|tokio|clipboard|decompress|new_streaming
+        run: |
+          sed -i 's/^  "json",$/  "serde_json",/' crates/polars-python/Cargo.toml
+          sed -E -i "/^  \"(${FEATURES})\",$/d" crates/polars-python/Cargo.toml py-polars/Cargo.toml
+
+      - name: Setup emsdk
+        uses: mymindstorm/setup-emsdk@v14
+        with:
+          # This should match the exact version of Emscripten used by Pyodide
+          version: 3.1.58
+
+      - name: Install LLVM
+        # This should match the major version of LLVM expected by Emscripten
+        run: |
+          wget https://apt.llvm.org/llvm.sh
+          chmod +x llvm.sh
+          sudo ./llvm.sh 19
+          echo "EM_LLVM_ROOT=/usr/lib/llvm-19/bin" >> $GITHUB_ENV
+
+      - name: Build wheel
+        uses: PyO3/maturin-action@v1
+        with:
+          command: build
+          target: wasm32-unknown-emscripten
+          args: >
+            --profile dev
+            --manifest-path py-polars/Cargo.toml
+            --interpreter python3.10
+          maturin-version: 1.7.4