From aea750051f7660cf61dbd2360a25ea0bd13efa3b Mon Sep 17 00:00:00 2001
From: Rinat Shigapov <rinatshigapov@gmail.com>
Date: Thu, 21 Nov 2019 09:34:26 -0600
Subject: [PATCH] fix dependencies (#146)

* fix requirements

* don't reuse build dependencies between different envs

* minor fix

* change the order of opencv and opencv-headless
---
 .dockerignore    |  6 ++++++
 .travis.yml      |  2 +-
 Dockerfile       |  7 +++++++
 README.rst       |  4 ++++
 requirements.txt |  6 ------
 setup.py         | 32 +++++++++++++++++++++++++++++---
 6 files changed, 47 insertions(+), 10 deletions(-)
 create mode 100644 .dockerignore
 create mode 100644 Dockerfile
 delete mode 100644 requirements.txt

diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000..8c22f226d
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,6 @@
+.git
+.gitignore
+*.egg-info
+.eggs/
+.mypy-cache
+pip-wheel-metadata
diff --git a/.travis.yml b/.travis.yml
index 4bffded0e..77a5c788f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,7 +8,7 @@ before_install:
   - sudo apt-get install -y ffmpeg
 
 install:
-  - pip install Cython opencv-python pyyaml codecov flake8 yapf isort
+  - rm -rf .eggs && pip install -e . codecov flake8 yapf isort
 
 cache:
   pip: true
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 000000000..e163b312c
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,7 @@
+FROM python:3.7
+
+WORKDIR /mmcv
+
+COPY . /mmcv
+
+RUN pip install -e .
diff --git a/README.rst b/README.rst
index bcf56745d..b2fb2e8ed 100644
--- a/README.rst
+++ b/README.rst
@@ -48,3 +48,7 @@ or install from source
     git clone https://github.com/open-mmlab/mmcv.git
     cd mmcv
     pip install -e .
+
+Note: If you would like to use :code:`opencv-python-headless` instead of :code:`opencv-python`,
+e.g., in a minimum container environment or servers without GUI,
+you can first install it before installing MMCV to skip the installation of :code:`opencv-python`.
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
deleted file mode 100644
index 3d3b616ca..000000000
--- a/requirements.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-addict
-numpy>=1.11.1
-pyyaml
-six
-requests
-opencv-python
diff --git a/setup.py b/setup.py
index f07d49b21..85911a4cb 100644
--- a/setup.py
+++ b/setup.py
@@ -1,17 +1,43 @@
 import platform
+import re
 import sys
 from io import open  # for Python 2 (identical to builtin in Python 3)
-from setuptools import Extension, find_packages, setup, dist
+from setuptools import Extension, dist, find_packages, setup
+
+from pkg_resources import DistributionNotFound, get_distribution
 
 dist.Distribution().fetch_build_eggs(['Cython', 'numpy>=1.11.1'])
 
 import numpy  # noqa: E402
 from Cython.Distutils import build_ext  # noqa: E402
 
+
+def choose_requirement(primary, secondary):
+    """If some version of primary requirement installed, return primary,
+    else return secondary.
+    """
+    try:
+        name = re.split(r'[!<>=]', primary)[0]
+        get_distribution(name)
+    except DistributionNotFound:
+        return secondary
+
+    return str(primary)
+
+
 install_requires = [
-    'numpy>=1.11.1', 'pyyaml', 'six', 'addict', 'requests', 'opencv-python',
-    'Cython'
+    'numpy>=1.11.1',
+    'pyyaml',
+    'six',
+    'addict',
+    'requests',
 ]
+# If first not installed install second package
+CHOOSE_INSTALL_REQUIRES = [('opencv-python-headless>=3', 'opencv-python>=3')]
+
+for main, secondary in CHOOSE_INSTALL_REQUIRES:
+    install_requires.append(choose_requirement(main, secondary))
+
 if sys.version_info < (3, 3):
     install_requires.append('backports.shutil_get_terminal_size')
 if sys.version_info < (3, 4):