Add temporary dir for optimizing artifacts

Remove existing artifacts before building

optimize_workspace.sh

@@ -7,18 +7,20 @@ export PATH="$PATH:/root/.cargo/bin"
 rustup toolchain list
 cargo --version
 
+# Delete already built artifacts
+rm -f target/wasm32-unknown-unknown/release/*/*.wasm
+
 # Build artifacts
 echo -n "Building artifacts in workspace..."
 /usr/local/bin/build_workspace.py
 echo "done."
 
 echo -n "Optimizing artifacts in workspace..."
-# Start clean
-rm -rf ./artifacts
-mkdir artifacts
-# Optimize and postprocess artifacts
+mkdir -p artifacts
+TMPDIR=$(mktemp -d artifacts.XXX)
+# Optimize artifacts
 (
-  cd artifacts
+  cd "$TMPDIR"
 
   for WASM in ../target/wasm32-unknown-unknown/release/*/*.wasm
   do
@@ -28,6 +30,13 @@ mkdir artifacts
     chmod -x "$BASE"
     echo "done."
   done
+	mv ./*.wasm ../artifacts
+)
+echo "done."
+echo -n "Post-processing artifacts in workspace..."
+(
+  cd artifacts
   sha256sum -- *.wasm >checksums.txt
 )
+rm -rf "$TMPDIR"
 echo "done."