Make pymongo optional again (#519)

* Make pymongo optional again

* Add test for running without optional deps

* Add new tox env to travis

* Add cpuinfo back in

.travis.yml

@@ -15,6 +15,8 @@ matrix:
     env: TOX_ENV=tensorflow-1
   - python: "3.6"
     env: TOX_ENV=tensorflow-2
+  - python: "3.7"
+    env: TOX_ENV=setup
   - python: "3.6"
     env: TOX_ENV=flake8
   - python: "3.6"

dev-requirements.txt

@@ -13,8 +13,7 @@ numpy==1.16.2
 packaging>=18.0
 pandas==0.24.2
 pbr==1.10.0
-py-cpuinfo==4.0
-pymongo==3.4.0
+# tests/test_utils.py depends on that pytest version is exactly 4.3.0
 pytest==4.3.0
 python-dateutil==2.6.0
 pytz==2016.10
@@ -27,3 +26,6 @@ tinydb==3.2.1
 tinydb-serialization==1.0.3
 wrapt==1.10.8
 scikit-learn==0.20.3
+pymongo==3.8.0
+py-cpuinfo==4.0
+

requirements.txt

@@ -4,12 +4,5 @@ jsonpickle>=0.9.3
 mock>=2.0.0
 munch>=2.0.4
 pbr>=1.10.0
-py>=1.4.32
-py-cpuinfo>=4.0
-six>=1.10.0
 wrapt>=1.10.8
-packaging>=18.0
-pymongo>=3.8.0
-
-# tests/test_utils.py depends on that pytest version is exactly 4.3.0
-pytest==4.3.0
+packaging>=18.0

sacred/observers/mongo.py

@@ -9,10 +9,6 @@
 import time
 from tempfile import NamedTemporaryFile
 
-import pymongo
-import pymongo.errors
-import gridfs
-
 import sacred.optional as opt
 from sacred.commandline_options import CommandLineOption
 from sacred.dependencies import get_digest
@@ -81,6 +77,8 @@ def create(cls, url=None, db_name='sacred', collection='runs',
         -------
         An instantiated MongoObserver.
         """
+        import pymongo
+        import gridfs
 
         if client is not None:
             if not isinstance(client, pymongo.MongoClient):
@@ -266,6 +264,8 @@ def log_metrics(self, metrics_by_name, info):
                     .append({"name": key, "id": str(result.upserted_id)})
 
     def insert(self):
+        import pymongo.errors
+
         if self.overwrite:
             return self.save()
 
@@ -318,8 +318,7 @@ def final_save(self, attempts):
                       "Most likely it is either the 'info' or the 'result'.",
                       file=sys.stderr)
 
-        if not os.path.exists(self.failure_dir):
-            os.makedirs(self.failure_dir)
+        os.makedirs(self.failure_dir, exist_ok=True)
         with NamedTemporaryFile(suffix='.pickle', delete=False,
                                 prefix='sacred_mongo_fail_{}_'.format(
                                     self.run_entry["_id"]
@@ -448,6 +447,7 @@ def log_metrics(self, metric_name, metrics_values, info):
                 .append({"name": metric_name, "id": str(result.upserted_id)})
 
     def save(self):
+        import pymongo
         try:
             self.runs.update_one({'_id': self.run_entry['_id']},
                                  {'$set': self.run_entry})
@@ -456,6 +456,7 @@ def save(self):
                                 '(most likely in the info)')
 
     def final_save(self, attempts):
+        import pymongo
         try:
             self.runs.update_one({'_id': self.run_entry['_id']},
                                  {'$set': self.run_entry}, upsert=True)

setup.py

@@ -49,7 +49,6 @@
         'py-cpuinfo>=4.0',
         'colorama>=0.4',
         'packaging>=18.0',
-        'pymongo>=3.8.0'
     ],
     tests_require=[
         'mock>=0.8, <3.0',

tox.ini

@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py35, py36, py37, flake8, tensorflow-1, tensorflow-2
+envlist = py35, py36, py37, setup, flake8, tensorflow-1, tensorflow-2
 # py32 does not work because of the 'wrapt' dependency
 # py33 is not supported by newer versions of numpy
 # py34 is not supported by newer versions of pandas
@@ -34,10 +34,18 @@ commands =
     pytest tests/test_stflow \
         {posargs}
 
+[testenv:setup]
+basepython = python
+deps = 
+    pytest==4.3.0
+    mock==2.0.0
+commands = 
+    pytest --ignore=tests/test_observers \
+        {posargs} 
+
 [testenv:flake8]
 basepython = python
 deps =
-    -rrequirements.txt
     flake8
     pep8-naming
     mccabe