fix build - only install mujoco for python 3.6, 3.7, (#2133)

* reverting to older version of 3.6 python to test if the build is failing because of that

* revert 3.7 to 3.7.3 for the build

* revert python 3.8 version to 3.8.1

* do not install mujoco on 3.8 and 3.9

* enable mujoco for 3.7

* .

* .

* .

* use regex to navigate python version dependent package installation

* .

.travis.yml

@@ -5,8 +5,8 @@ python:
 services:
   - docker
 env:
-  - PY_VER=3.6.12
-  - PY_VER=3.7.9
+  - PY_VER=3.6.8
+  - PY_VER=3.7.3
   - PY_VER=3.8.6
   - PY_VER=3.9.0
 
@@ -21,4 +21,4 @@ deploy:
     password: $TWINE_PASSWORD
     on:
         tags: true
-        condition: $PY_VER = 3.6.12
+        condition: $PY_VER = 3.6.8

py.Dockerfile

@@ -9,8 +9,8 @@ RUN \
     curl -O https://www.roboti.us/download/mjpro150_linux.zip  && \
     unzip mjpro150_linux.zip
 
-ARG MUJOCO_KEY
 ARG PYTHON_VER
+ARG MUJOCO_KEY
 ENV MUJOCO_KEY=$MUJOCO_KEY
 
 ENV LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/root/.mujoco/mjpro150/bin
@@ -19,7 +19,7 @@ RUN pip install pytest pytest-forked lz4
 
 COPY . /usr/local/gym/
 WORKDIR /usr/local/gym/
-RUN pip install .[all]
+RUN bash -c "[[ $PYTHON_VER =~ 3\.[6-7]\.[0-9] ]] && pip install -e .[all] || pip install -e .[nomujoco]"
 
 ENTRYPOINT ["/usr/local/gym/bin/docker_entrypoint"]
 CMD ["pytest","--forked"]

setup.py

@@ -15,7 +15,8 @@
 }
 
 # Meta dependency groups.
-extras['all'] = [item for group in extras.values() for item in group]
+extras['nomujoco'] = list(set([item for name, group in extras.items() if name != 'mujoco' and name != "robotics" for item in group]))
+extras['all'] = list(set([item for group in extras.values() for item in group]))
 
 setup(name='gym',
       version=VERSION,