Check bazel version with the workspace

diff --git a/WORKSPACE b/WORKSPACE
index fd4aa93..e1b7b23 100644
--- a/WORKSPACE
+++ b/WORKSPACE

@@ -1,6 +1,8 @@
 workspace(name = "build_bazel_e4b")
 
 load("//tools/build_defs:eclipse.bzl", "load_eclipse_deps")
+load(":bazel_version.bzl", "check_bazel_version")
+check_bazel_version("0.4.5")
 
 load_eclipse_deps()
 

diff --git a/bazel_version.bzl b/bazel_version.bzl
new file mode 100644
index 0000000..9d78389
--- /dev/null
+++ b/bazel_version.bzl

@@ -0,0 +1,31 @@
+# Copied from https://github.com/tensorflow/tensorflow/blob/dfa7d2d2953c3d33d2e8deb898240be008de5be6/tensorflow/workspace.bzl
+
+# Parse the bazel version string from `native.bazel_version`.
+def _parse_bazel_version(bazel_version):
+  # Remove commit from version.
+  version = bazel_version.split(" ", 1)[0]
+
+  # Split into (release, date) parts and only return the release
+  # as a tuple of integers.
+  parts = version.split('-', 1)
+
+  # Turn "release" into a tuple of strings
+  version_tuple = ()
+  for number in parts[0].split('.'):
+    version_tuple += (str(number),)
+  return version_tuple
+
+# Check that a specific bazel version is being used.
+def check_bazel_version(bazel_version):
+  if "bazel_version" not in dir(native):
+    fail("\nCurrent Bazel version is lower than 0.2.1, expected at least %s\n" % bazel_version)
+  elif not native.bazel_version:
+    print("\nCurrent Bazel is not a release version, cannot check for compatibility.")
+    print("Make sure that you are running at least Bazel %s.\n" % bazel_version)
+  else:
+    current_bazel_version = _parse_bazel_version(native.bazel_version)
+    minimum_bazel_version = _parse_bazel_version(bazel_version)
+    if minimum_bazel_version > current_bazel_version:
+      fail("\nCurrent Bazel version is {}, expected at least {}\n".format(
+          native.bazel_version, bazel_version))
+  pass