Standard TensorBoard build handles no TensorFlow

tensorboard/BUILD

@@ -27,32 +27,7 @@ py_binary(
         ":program",
         "//tensorboard:expect_tensorflow_installed",
         "//tensorboard/plugins:base_plugin",
-    ],
-)
-
-# The TensorBoard binary that serves the webapp without TensorFlow.
-py_binary(
-    name = "tensorboard-notf",
-    srcs = ["main_notf.py"],
-    data = ["webfiles.zip"],
-    main = "main_notf.py",
-    srcs_version = "PY2AND3",
-    visibility = ["//visibility:public"],
-    deps = [
-        ":program",
-        "//tensorboard/compat:no_tensorflow",
-        "//tensorboard/plugins:base_plugin",
-        "//tensorboard/plugins/audio:audio_plugin",
-        "//tensorboard/plugins/core:core_plugin",
-        "//tensorboard/plugins/custom_scalar:custom_scalars_plugin",
-        "//tensorboard/plugins/distribution:distributions_plugin",
-        "//tensorboard/plugins/graph:graphs_plugin",
-        "//tensorboard/plugins/histogram:histograms_plugin",
-        "//tensorboard/plugins/image:images_plugin",
-        "//tensorboard/plugins/pr_curve:pr_curves_plugin",
-        "//tensorboard/plugins/projector:projector_plugin",
-        "//tensorboard/plugins/scalar:scalars_plugin",
-        "//tensorboard/plugins/text:text_plugin",
+        "//tensorboard/util:tb_logging",
     ],
 )
 
@@ -181,18 +156,18 @@ py_library(
     deps = [
         "//tensorboard/plugins:base_plugin",
         "//tensorboard/plugins/audio:audio_plugin",
-        "//tensorboard/plugins/beholder:beholder_plugin",
+        "//tensorboard/plugins/beholder:beholder_plugin_loader",
         "//tensorboard/plugins/core:core_plugin",
         "//tensorboard/plugins/custom_scalar:custom_scalars_plugin",
         "//tensorboard/plugins/debugger:debugger_plugin_loader",
         "//tensorboard/plugins/distribution:distributions_plugin",
         "//tensorboard/plugins/graph:graphs_plugin",
         "//tensorboard/plugins/histogram:histograms_plugin",
-        "//tensorboard/plugins/hparams:hparams_plugin",
+        "//tensorboard/plugins/hparams:hparams_plugin_loader",
         "//tensorboard/plugins/image:images_plugin",
-        "//tensorboard/plugins/interactive_inference:interactive_inference_plugin",
+        "//tensorboard/plugins/interactive_inference:interactive_inference_plugin_loader",
         "//tensorboard/plugins/pr_curve:pr_curves_plugin",
-        "//tensorboard/plugins/profile:profile_plugin",
+        "//tensorboard/plugins/profile:profile_plugin_loader",
         "//tensorboard/plugins/projector:projector_plugin",
         "//tensorboard/plugins/scalar:scalars_plugin",
         "//tensorboard/plugins/text:text_plugin",

tensorboard/default.py

@@ -31,20 +31,23 @@
 import logging
 import os
 
+from tensorboard.compat import tf
 from tensorboard.plugins import base_plugin
 from tensorboard.plugins.audio import audio_plugin
-from tensorboard.plugins.beholder import beholder_plugin
+from tensorboard.plugins.beholder import beholder_plugin_loader
 from tensorboard.plugins.core import core_plugin
 from tensorboard.plugins.custom_scalar import custom_scalars_plugin
 from tensorboard.plugins.debugger import debugger_plugin_loader
 from tensorboard.plugins.distribution import distributions_plugin
 from tensorboard.plugins.graph import graphs_plugin
 from tensorboard.plugins.histogram import histograms_plugin
-from tensorboard.plugins.hparams import hparams_plugin
+from tensorboard.plugins.hparams import hparams_plugin_loader
 from tensorboard.plugins.image import images_plugin
-from tensorboard.plugins.interactive_inference import interactive_inference_plugin
+from tensorboard.plugins.interactive_inference import (
+    interactive_inference_plugin_loader
+)
 from tensorboard.plugins.pr_curve import pr_curves_plugin
-from tensorboard.plugins.profile import profile_plugin
+from tensorboard.plugins.profile import profile_plugin_loader
 from tensorboard.plugins.projector import projector_plugin
 from tensorboard.plugins.scalar import scalars_plugin
 from tensorboard.plugins.text import text_plugin
@@ -54,7 +57,7 @@
 
 _PLUGINS = [
     core_plugin.CorePluginLoader(),
-    beholder_plugin.BeholderPlugin,
+    beholder_plugin_loader.BeholderPluginLoader(),
     scalars_plugin.ScalarsPlugin,
     custom_scalars_plugin.CustomScalarsPlugin,
     images_plugin.ImagesPlugin,
@@ -65,10 +68,10 @@
     pr_curves_plugin.PrCurvesPlugin,
     projector_plugin.ProjectorPlugin,
     text_plugin.TextPlugin,
-    interactive_inference_plugin.InteractiveInferencePlugin,
-    profile_plugin.ProfilePluginLoader(),
+    interactive_inference_plugin_loader.InteractiveInferencePluginLoader(),
+    profile_plugin_loader.ProfilePluginLoader(),
     debugger_plugin_loader.DebuggerPluginLoader(),
-    hparams_plugin.HParamsPlugin,
+    hparams_plugin_loader.HParamsPluginLoader(),
 ]
 
 def get_plugins():

tensorboard/main.py

@@ -37,18 +37,28 @@
 
 import sys
 
-# Import TensorFlow here to fail immediately if it's not present, even though we
-# don't actually use it yet, which results in a clearer error.
-import tensorflow as tf  # pylint: disable=unused-import
-
 from tensorboard import default
 from tensorboard import program
+from tensorboard.compat import tf
 from tensorboard.plugins import base_plugin
+from tensorboard.util import tb_logging
+
 
+logger = tb_logging.get_logger()
 
 def run_main():
   """Initializes flags and calls main()."""
   program.setup_environment()
+
+  if getattr(tf, '__version__', 'stub') == 'stub':
+    # Unless the user has explicitly requested running without TensorFlow by setting the
+    # TENSORBOARD_NO_TF environment variable, we check for TensorFlow here so that if it's
+    # missing we generate a clear and immediate error rather than partial functionality.
+    # TODO(#2027): Remove environment check once we have placeholder UI
+    if os.getenv('TENSORBOARD_NO_TF') is None:
+      import tensorflow  # pylint: disable=unused-import
+    logger.warn("TensorFlow installation not found - running with reduced feature set.")
+
   tensorboard = program.TensorBoard(default.get_plugins(),
                                     program.get_default_assets_zip_provider())
   try:

tensorboard/plugins/beholder/BUILD

@@ -47,6 +47,18 @@ py_library(
     ],
 )
 
+py_library(
+    name = "beholder_plugin_loader",
+    srcs = ["beholder_plugin_loader.py"],
+    srcs_version = "PY2AND3",
+    deps = [
+        ":beholder_plugin",
+        "//tensorboard/plugins:base_plugin",
+        "//tensorboard/util:tb_logging",
+        "@org_pythonhosted_six",
+    ],
+)
+
 py_binary(
     name = "beholder_demo",
     srcs = ["beholder_demo.py"],

tensorboard/plugins/beholder/__init__.py

@@ -12,5 +12,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from tensorboard.plugins.beholder.beholder import Beholder
-from tensorboard.plugins.beholder.beholder import BeholderHook
+# Only import Beholder API when tensorflow is available.
+try:
+  # pylint: disable=g-import-not-at-top,unused-import
+  import tensorflow
+except ImportError:
+  pass
+else:
+  from tensorboard.plugins.beholder.beholder import Beholder
+  from tensorboard.plugins.beholder.beholder import BeholderHook

tensorboard/plugins/beholder/beholder_plugin_loader.py

@@ -0,0 +1,46 @@
+# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""Wrapper around plugin to conditionally enable it."""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from tensorboard.plugins import base_plugin
+
+
+class BeholderPluginLoader(base_plugin.TBLoader):
+  """BeholderPlugin factory.
+
+  This class checks for `tensorflow` install and dependency.
+  """
+
+  def load(self, context):
+    """Returns the plugin, if possible.
+
+    Args:
+      context: The TBContext flags.
+
+    Returns:
+      A BeholderPlugin instance or None if it couldn't be loaded.
+    """
+    try:
+      # pylint: disable=g-import-not-at-top,unused-import
+      import tensorflow
+    except ImportError:
+      return
+    # pylint: disable=g-import-not-at-top
+    from tensorboard.plugins.beholder.beholder_plugin import BeholderPlugin
+    return BeholderPlugin(context)

tensorboard/plugins/debugger/debugger_plugin_loader.py

@@ -95,6 +95,11 @@ def load(self, context):
             context.flags.debugger_port > 0):
       return None
     flags = context.flags
+    try:
+      # pylint: disable=g-import-not-at-top,unused-import
+      import tensorflow
+    except ImportError:
+      return None
     try:
       # pylint: disable=line-too-long,g-import-not-at-top
       from tensorboard.plugins.debugger import debugger_plugin as debugger_plugin_lib

tensorboard/plugins/hparams/BUILD

@@ -40,6 +40,16 @@ py_library(
     ],
 )
 
+py_library(
+    name = "hparams_plugin_loader",
+    srcs = ["hparams_plugin_loader.py"],
+    srcs_version = "PY2AND3",
+    deps = [
+        ":hparams_plugin",
+        "//tensorboard/plugins:base_plugin",
+    ],
+)
+
 py_test(
     name = "list_session_groups_test",
     size = "small",