Use bazel disk cache for all CI jobs (#5144)

.travis.yml

@@ -112,8 +112,11 @@ matrix:
         - if [ $RAY_CI_LINUX_WHEELS_AFFECTED != "1" ]; then exit; fi
         - ./ci/suppress_output ./ci/travis/install-dependencies.sh
 
-        # This command should be kept in sync with ray/python/README-building-wheels.md.
-        - ./ci/suppress_output docker run --rm -w /ray -v `pwd`:/ray -ti rayproject/arrow_linux_x86_64_base:latest /ray/python/build-wheel-manylinux1.sh
+        # Mount bazel cache dir to the docker container.
+        - export MOUNT_BAZEL_CACHE="-v $HOME/ray-bazel-cache:/root/ray-bazel-cache -e TRAVIS=true"
+        # This command should be kept in sync with ray/python/README-building-wheels.md,
+        # except the `$MOUNT_BAZEL_CACHE` part.
+        - ./ci/suppress_output docker run --rm -w /ray -v `pwd`:/ray $MOUNT_BAZEL_CACHE -ti rayproject/arrow_linux_x86_64_base:latest /ray/python/build-wheel-manylinux1.sh
       script:
         - if [ $RAY_CI_LINUX_WHEELS_AFFECTED != "1" ]; then exit; fi
 
@@ -140,7 +143,6 @@ install:
   - if [ $RAY_CI_TUNE_AFFECTED != "1" ] && [ $RAY_CI_RLLIB_AFFECTED != "1" ] && [ $RAY_CI_PYTHON_AFFECTED != "1" ]; then exit; fi
 
   - ./ci/suppress_output ./ci/travis/install-bazel.sh
-  - ./ci/suppress_output ./ci/travis/setup-bazel-cache.sh
   - ./ci/suppress_output ./ci/travis/install-dependencies.sh
   - export PATH="$HOME/miniconda/bin:$PATH"
   - ./ci/suppress_output ./ci/travis/install-ray.sh

ci/travis/install-bazel.sh

@@ -21,3 +21,9 @@ wget -O install.sh $URL
 chmod +x install.sh
 ./install.sh --user
 rm -f install.sh
+
+if [[ "$TRAVIS" == "true"  ]]; then
+  # Use bazel disk cache if this script is running in Travis.
+  mkdir -p $HOME/ray-bazel-cache
+  echo "build --disk_cache=$HOME/ray-bazel-cache" >> $HOME/.bazelrc
+fi

ci/travis/setup-bazel-cache.sh

@@ -1,5 +0,0 @@
-set -x
-set -e
-
-mkdir -p $HOME/ray-bazel-cache
-echo "build --disk_cache=$HOME/ray-bazel-cache" >> .bazelrc