Pulling out strip_hashes and add --no-deps flag

Dockerfile

@@ -8,11 +8,10 @@ WORKDIR /opt/certbot
 COPY CHANGELOG.md README.rst setup.py src/
 
 # Generate constraints file to pin dependency versions
-COPY letsencrypt-auto-source/pieces/dependency-requirements.txt hashed_requirements.txt
+COPY letsencrypt-auto-source/pieces/dependency-requirements.txt .
 COPY tools /opt/certbot/tools
-RUN /opt/certbot/tools/docker_constraints.py \
-    hashed_requirements.txt unhashed_requirements.txt \
-    tools/dev_constraints.txt docker_constraints.txt
+RUN sh -c 'cat dependency-requirements.txt | /opt/certbot/tools/strip_hashes.py > unhashed_requirements.txt'
+RUN sh -c 'cat tools/dev_constraints.txt unhashed_requirements.txt | /opt/certbot/tools/merge_requirements.py > docker_constraints.txt'
 
 COPY acme src/acme
 COPY certbot src/certbot
@@ -29,9 +28,8 @@ RUN apk add --no-cache --virtual .build-deps \
         openssl-dev \
         musl-dev \
         libffi-dev \
-    && pip install --no-cache-dir \
-        --requirement /opt/certbot/unhashed_requirements.txt \
-        --constraint /opt/certbot/docker_constraints.txt \
+    && pip install -r /opt/certbot/dependency-requirements.txt \
+    && pip install --no-cache-dir --no-deps \
         --editable /opt/certbot/src/acme \
         --editable /opt/certbot/src \
     && apk del .build-deps

tools/docker_constraints.py

@@ -1,23 +0,0 @@
-#!/usr/bin/env python
-"""Generates constraints file to pin dependency versions in Docker images.
-
-Removes hashes from supplied requirements file and merges it with existing
-constraints file. Versions in requirements take precedence over constraints.
-
-Generates interstitial with hashes stripped from requirements.
-"""
-
-import sys
-
-import pip_install
-import merge_requirements
-
-def main(hashed_reqs_in, unhashed_reqs_out,
-         constraints_in, constraints_out):
-    with open(unhashed_reqs_out, 'w') as fd:
-        fd.write(pip_install.remove_requirements_hashes(hashed_reqs_in))
-    with open(constraints_out, 'w') as fd:
-        fd.write(merge_requirements.main(constraints_in, unhashed_reqs_out))
-
-if __name__ == '__main__':
-    main(sys.argv[1], sys.argv[2], sys.argv[3], sys.argv[4])

tools/pip_install.py

@@ -19,6 +19,7 @@ import tempfile
 
 import merge_requirements as merge_module
 import readlink
+import strip_hashes
 
 
 def find_tools_path():
@@ -40,23 +41,14 @@ def certbot_oldest_processing(tools_path, args, test_constraints):
     return requirements
 
 
-def remove_requirements_hashes(filename):
-    out_lines = []
-    with open(filename, 'r') as fd:
-        in_data = fd.readlines()
-    for line in in_data:
-        search = re.search(r'^(\S*==\S*).*$', line)
-        if search:
-            out_lines.append(search.group(1))
-    return os.linesep.join(out_lines)
-
-
 def certbot_normal_processing(tools_path, test_constraints):
     repo_path = os.path.dirname(tools_path)
     certbot_requirements = os.path.normpath(os.path.join(
         repo_path, 'letsencrypt-auto-source/pieces/dependency-requirements.txt'))
+    with open(certbot_requirements, 'r') as fd:
+        data = fd.readlines()
     with open(test_constraints, 'w') as fd:
-        fd.write(remove_requirements_hashes(certbot_requirements))
+        fd.write(strip_hashes.main(data))
 
 
 def merge_requirements(tools_path, requirements, test_constraints, all_constraints):

tools/strip_hashes.py

@@ -0,0 +1,16 @@
+#!/usr/bin/env python
+
+import os
+import re
+import sys
+
+def main(args):
+    out_lines = []
+    for line in args:
+        search = re.search(r'^(\S*==\S*).*$', line)
+        if search:
+            out_lines.append(search.group(1))
+    return os.linesep.join(out_lines)
+
+if __name__ == '__main__':
+    print(main(sys.argv[1:]))