Add requirements files for install, test and plugin dependencies

Add `.in` and `.txt` requirements files for BuildStream's pure python
dependencies. For each pair, the `.in` file is supposed to capture the
loose version requirements, and the corresponding `.txt` file is
supposed to have frozen requirements. We have 3 such sets:

* `requirements`: BuildStream's runtime dependencies
* `dev-requirements`: Dependencies for running tests
* `plugin-requirements`: Dependencies for core plugins

Note that the frozen requirements files will only be used for testing
purposes, and `setup.py` will continue to read loose requirements.

8 files changed, 88 insertions, 29 deletions

diff --git a/MANIFEST.in b/MANIFEST.in
index b8429830a..96fce72b3 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -31,7 +31,12 @@ include .pylintrc
 recursive-include buildstream/_protos *.proto
 
 # Requirements files
+include requirements.in
+include requirements.txt
+include dev-requirements.in
 include dev-requirements.txt
+include plugin-requirements.in
+include plugin-requirements.txt
 
 # Versioneer
 include versioneer.py
diff --git a/dev-requirements.in b/dev-requirements.in
new file mode 100644
index 000000000..42c300f39
--- /dev/null
+++ b/dev-requirements.in
@@ -0,0 +1,11 @@
+coverage == 4.4.0
+pylint
+pytest >= 3.9
+pytest-codestyle >= 1.4.0
+pytest-cov >= 2.5.0
+pytest-datafiles >= 2.0
+pytest-env
+pytest-pylint
+pytest-xdist
+pytest-timeout
+pyftpdlib
diff --git a/dev-requirements.txt b/dev-requirements.txt
index 42c300f39..28e3560e4 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,11 +1,28 @@
-coverage == 4.4.0
-pylint
-pytest >= 3.9
-pytest-codestyle >= 1.4.0
-pytest-cov >= 2.5.0
-pytest-datafiles >= 2.0
-pytest-env
-pytest-pylint
-pytest-xdist
-pytest-timeout
-pyftpdlib
+coverage==4.4
+pylint==2.2.2
+pytest==4.0.2
+pytest-codestyle==1.4.0
+pytest-cov==2.6.0
+pytest-datafiles==2.0
+pytest-env==0.6.2
+pytest-pylint==0.13.0
+pytest-xdist==1.25.0
+pytest-timeout==1.3.3
+pyftpdlib==1.5.4
+## The following requirements were added by pip freeze:
+apipkg==1.5
+astroid==2.1.0
+atomicwrites==1.2.1
+attrs==18.2.0
+execnet==1.5.0
+isort==4.3.4
+lazy-object-proxy==1.3.1
+mccabe==0.6.1
+more-itertools==5.0.0
+pluggy==0.8.0
+py==1.7.0
+pycodestyle==2.4.0
+pytest-forked==0.2
+six==1.12.0
+typed-ast==1.1.1
+wrapt==1.10.11
diff --git a/plugin-requirements.in b/plugin-requirements.in
new file mode 100644
index 000000000..e3527285d
--- /dev/null
+++ b/plugin-requirements.in
@@ -0,0 +1,2 @@
+arpy
+PyGObject
diff --git a/plugin-requirements.txt b/plugin-requirements.txt
new file mode 100644
index 000000000..6841612bd
--- /dev/null
+++ b/plugin-requirements.txt
@@ -0,0 +1,4 @@
+arpy==1.1.1
+PyGObject==3.30.4
+## The following requirements were added by pip freeze:
+pycairo==1.18.0
diff --git a/requirements.in b/requirements.in
new file mode 100644
index 000000000..7313d7dcf
--- /dev/null
+++ b/requirements.in
@@ -0,0 +1,15 @@
+Click
+grpcio >= 1.10
+jinja2 >= 2.10
+pluginbase
+protobuf >= 3.5
+psutil
+# According to ruamel.yaml's PyPI page, we are suppose to use
+# "<=0.15" in production until 0.15 becomes API stable.
+# However we need ruamel.yaml 0.15.41 or greater for Python 3.7.
+# We know that ruamel.yaml 0.15.52 breaks API in a way that
+# is incompatible with BuildStream.
+#
+# See issues #571 and #790.
+ruamel.yaml >= 0.15.41, < 0.15.52
+setuptools
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 000000000..17df16af4
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,18 @@
+Click==7.0
+grpcio==1.17.1
+pluginbase==0.7
+protobuf==3.6.1
+psutil==5.4.8
+# According to ruamel.yaml's PyPI page, we are suppose to use
+# "<=0.15" in production until 0.15 becomes API stable.
+# However we need ruamel.yaml 0.15.41 or greater for Python 3.7.
+# We know that ruamel.yaml 0.15.52 breaks API in a way that
+# is incompatible with BuildStream.
+#
+# See issues #571 and #790.
+ruamel.yaml==0.15.51
+setuptools==39.0.1
+## The following requirements were added by pip freeze:
+Jinja2==2.10
+MarkupSafe==1.1.0
+six==1.12.0
diff --git a/setup.py b/setup.py
index 872e7da4e..ddcb03d6a 100755
--- a/setup.py
+++ b/setup.py
@@ -270,9 +270,12 @@ def get_cmdclass():
 #####################################################
 #               Gather requirements                 #
 #####################################################
-with open('dev-requirements.txt') as dev_reqs:
+with open('dev-requirements.in') as dev_reqs:
     dev_requires = dev_reqs.read().splitlines()
 
+with open('requirements.in') as install_reqs:
+    install_requires = install_reqs.read().splitlines()
+
 #####################################################
 #     Prepare package description from README       #
 #####################################################
@@ -334,23 +337,7 @@ setup(name='BuildStream',
               os.path.join('buildstream', 'data', 'bst')
           ])
       ],
-      install_requires=[
-          'setuptools',
-          'psutil',
-          # According to ruamel.yaml's PyPI page, we are suppose to use
-          # "<=0.15" in production until 0.15 becomes API stable.
-          # However we need ruamel.yaml 0.15.41 or greater for Python 3.7.
-          # We know that ruamel.yaml 0.15.52 breaks API in a way that
-          # is incompatible with BuildStream.
-          #
-          # See issues #571 and #790.
-          'ruamel.yaml >= 0.15.41, < 0.15.52',
-          'pluginbase',
-          'Click >= 7.0',
-          'jinja2 >= 2.10',
-          'protobuf >= 3.5',
-          'grpcio >= 1.10',
-      ],
+      install_requires=install_requires,
       entry_points=bst_install_entry_points,
       tests_require=dev_requires,
       zip_safe=False)