wasm-size.yml

name: WASM Size Budget

# Enforces per-contract WASM size budgets so accidental bloat is caught in CI
# before it reaches mainnet deployment.  Budgets are intentionally conservative
# and should be updated via a deliberate PR if a contract genuinely needs more
# space (e.g. a new feature module).
#
# Budget table (release build, wasm32v1-none, opt-level=z + LTO):
#   hello-world        :   20 KB   – toy example, must stay tiny
#   governance-events  :   24 KB   – pure event types + emitters, no logic
#   predictify-hybrid  :  900 KB   – full prediction-market contract
#
# The governance-events crate was added in FWC26 (Stellar Wave).

on:
  push:
    branches: [ "master", "main" ]
  pull_request:
    branches: [ "master", "main" ]

jobs:
  check-size:
    runs-on: macos-latest

    steps:
    - uses: actions/checkout@v4

    - name: Install Rust
      run: |
        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
        source $HOME/.cargo/env
        rustup target add wasm32v1-none

    - name: Install Stellar CLI
      run: |
        brew update
        brew install stellar-cli

    - name: Build contracts (release, wasm32v1-none)
      run: |
        source $HOME/.cargo/env
        stellar contract build

    # ── Per-contract size gates ──────────────────────────────────────────────
    # Each WASM is checked against its own budget.  Any file that does not
    # match a known contract name triggers a strict 20 KB fallback so unknown
    # contracts cannot sneak through with unbounded size.

    - name: Check WASM sizes
      run: |
        set -euo pipefail
        source $HOME/.cargo/env

        # Budgets in bytes (release + opt-level=z + LTO)
        BUDGET_HELLO_WORLD=20480          # 20 KB
        BUDGET_GOVERNANCE_EVENTS=24576    # 24 KB  (FWC26 governance-events crate)
        BUDGET_PREDICTIFY_HYBRID=921600   # 900 KB
        BUDGET_FALLBACK=20480             # 20 KB  (any unknown contract)

        FAIL=0

        for wasm_file in target/wasm32v1-none/release/*.wasm; do
          [ -f "$wasm_file" ] || continue

          SIZE=$(stat -f%z "$wasm_file")
          BASE=$(basename "$wasm_file" .wasm)

          case "$BASE" in
            hello_world)
              BUDGET=$BUDGET_HELLO_WORLD ;;
            governance_events)
              BUDGET=$BUDGET_GOVERNANCE_EVENTS ;;
            predictify_hybrid)
              BUDGET=$BUDGET_PREDICTIFY_HYBRID ;;
            *)
              BUDGET=$BUDGET_FALLBACK ;;
          esac

          BUDGET_KB=$(( BUDGET / 1024 ))
          SIZE_KB=$(echo "scale=1; $SIZE / 1024" | bc)

          if [ "$SIZE" -gt "$BUDGET" ]; then
            echo "::error file=$wasm_file::WASM size budget exceeded: $BASE = ${SIZE_KB} KB (budget ${BUDGET_KB} KB)"
            FAIL=1
          else
            echo "OK  $BASE: ${SIZE_KB} KB / ${BUDGET_KB} KB"
          fi
        done

        if [ "$FAIL" -eq 1 ]; then
          echo ""
          echo "One or more contracts exceeded their WASM size budget."
          echo "If the growth is intentional, update the budget table in"
          echo ".github/workflows/wasm-size.yml with a justification comment."
          exit 1
        fi

        echo ""
        echo "All contracts are within their WASM size budgets."

    # ── Size report (informational, never fails the build) ───────────────────
    - name: Report WASM sizes
      if: always()
      run: |
        echo "### WASM size report" >> $GITHUB_STEP_SUMMARY
        echo "" >> $GITHUB_STEP_SUMMARY
        echo "| Contract | Size |" >> $GITHUB_STEP_SUMMARY
        echo "|---|---|" >> $GITHUB_STEP_SUMMARY
        for wasm_file in target/wasm32v1-none/release/*.wasm; do
          [ -f "$wasm_file" ] || continue
          SIZE=$(stat -f%z "$wasm_file")
          SIZE_KB=$(echo "scale=1; $SIZE / 1024" | bc)
          BASE=$(basename "$wasm_file" .wasm)
          echo "| \`$BASE\` | ${SIZE_KB} KB |" >> $GITHUB_STEP_SUMMARY
        done