Test data dir (#951)

* test data download working

Signed-off-by: Tomasz Kornuta <tkornuta@nvidia.com>

* formatting fix

Signed-off-by: Tomasz Kornuta <tkornuta@nvidia.com>

* description

Signed-off-by: Tomasz Kornuta <tkornuta@nvidia.com>

* polish

Signed-off-by: Tomasz Kornuta <tkornuta@nvidia.com>

* rename

Signed-off-by: Tomasz Kornuta <tkornuta@nvidia.com>

.gitignore

@@ -150,6 +150,9 @@ dmypy.json
 cifar-10-batches-py
 *.tar.gz
 
+# Test data.
+tests/.data
+
 # outputs folder
 examples/*/outputs
 examples/*/wandb
@@ -161,4 +164,4 @@ docs/sources/source/test_build/
 
 # Checkpoints, config files and temporary files created in tutorials.
 examples/neural_graphs/*.chkpt
-examples/neural_graphs/*.yml
+examples/neural_graphs/*.yml

tests/conftest.py

@@ -12,10 +12,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import tarfile
+import urllib.request
+from os import mkdir
+from os.path import dirname, exists, getsize, join
+from shutil import rmtree
 
 import pytest
 
-from nemo import logging
+# Those variables probably should go to main NeMo configuration file (config.yaml).
+__TEST_DATA_FILENAME = "test_data.tar.gz"
+__TEST_DATA_URL = "https://github.com/NVIDIA/NeMo/releases/download/v0.11.0/"
+__TEST_DATA_SUBDIR = ".data"
 
 
 def pytest_addoption(parser):
@@ -43,3 +51,61 @@ def pytest_configure(config):
     config.addinivalue_line(
         "markers", "run_only_on(device): runs the test only on a given device [CPU | GPU]",
     )
+
+
+@pytest.fixture()
+def test_data_dir():
+    """ Fixture returns test_data_dir. """
+    # Test dir.
+    test_data_dir_ = join(dirname(__file__), __TEST_DATA_SUBDIR)
+    return test_data_dir_
+
+
+def pytest_configure(config):
+    """
+    Initial configuration of conftest.
+    The function checks if test_data.tar.gz is present in tests/.data.
+    If so, compares its size with github's test_data.tar.gz.
+    If file absent or sizes not equal, function downloads the archive from github and unpacks it.
+    """
+    # Test dir and archive filepath.
+    test_dir = join(dirname(__file__), __TEST_DATA_SUBDIR)
+    test_data_archive = join(dirname(__file__), __TEST_DATA_SUBDIR, __TEST_DATA_FILENAME)
+
+    # Get size of local test_data archive.
+    try:
+        test_data_local_size = getsize(test_data_archive)
+    except:
+        # File does not exist.
+        test_data_local_size = -1
+
+    # Get size of remote test_data archive.
+    url = __TEST_DATA_URL + __TEST_DATA_FILENAME
+    u = urllib.request.urlopen(url)
+    # Get metadata.
+    meta = u.info()
+    test_data_remote_size = int(meta["Content-Length"])
+
+    # Compare sizes.
+    if test_data_local_size != test_data_remote_size:
+        print(
+            "Downloading the `{}` test archive from `{}`, please wait...".format(__TEST_DATA_FILENAME, __TEST_DATA_URL)
+        )
+        # Remove .data folder.
+        if exists(test_dir):
+            rmtree(test_dir)
+        # Create one .data folder.
+        mkdir(test_dir)
+        # Download
+        urllib.request.urlretrieve(url, test_data_archive)
+        # Extract tar
+        print("Extracting the `{}` test archive, please wait...".format(test_data_archive))
+        tar = tarfile.open(test_data_archive)
+        tar.extractall(path=test_dir)
+        tar.close()
+    else:
+        print(
+            "A valid `{}` test archive ({}B) found in the `{}` folder.".format(
+                __TEST_DATA_FILENAME, test_data_local_size, test_dir
+            )
+        )

tests/test_data_dir.py

@@ -0,0 +1,27 @@
+# Copyright (c) 2020, NVIDIA CORPORATION.  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.
+
+
+from os.path import exists, join
+
+import pytest
+
+
+class TestDataDir:
+    @pytest.mark.unit
+    def test_test_data_dir(self, test_data_dir):
+        """" Just a dummy tests showing how to use the test_data_dir fixture. """
+        # test_data_dir contains the absolute path to nemo -> tests/.data
+        assert exists(test_data_dir)
+        assert exists(join(test_data_dir, "test_data.tar.gz"))