Fix race condition when rebuilding proto files. (#813)

Signed-off-by: Cody Littley <[email protected]>

api/builder/clean.sh

@@ -7,8 +7,19 @@ SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
 
 API_DIR="${SCRIPT_DIR}/.."
 GRPC_DIR="${API_DIR}/grpc"
-find "${GRPC_DIR}" -name '*.pb.go' -type f | xargs rm -rf
+
+if [ -d "${GRPC_DIR}" ]; then
+  # Delete all compiled protobufs
+  find "${GRPC_DIR}" -name '*.pb.go' -type f | xargs rm -rf
+  # Delete all empty directories
+  find "${GRPC_DIR}" -type d -empty -delete
+fi
 
 DISPERSER_DIR="$SCRIPT_DIR/../../disperser"
 DISPERSER_GRPC_DIR="$DISPERSER_DIR/api/grpc"
-find "${DISPERSER_GRPC_DIR}" -name '*.pb.go' -type f | xargs rm -rf
+if [ -d "${DISPERSER_GRPC_DIR}" ]; then
+  # Delete all compiled protobufs
+  find "${DISPERSER_GRPC_DIR}" -name '*.pb.go' -type f | xargs rm -rf
+  # Delete all empty directories
+  find "${DISPERSER_GRPC_DIR}" -type d -empty -delete
+fi