Read lorry prefix from yaml file

This adds PythonLorryExtension class to python.to_lorry to run the extension
in a more conventional way. Previously the PythonExtension class
was used to execute any of the extensions (it would call the extensions main()
function). We move away from this so the
extension can access useful methods, such as local_data_path(), that are
provided by the ImportExtension class.

This also removes use of pkg_resources.parse_requirement which is redundant.
This also removes the unused import of select.

1 files changed, 39 insertions, 30 deletions

diff --git a/baserockimport/exts/python.to_lorry b/baserockimport/exts/python.to_lorry
index accc9dc..06ee31d 100755
--- a/baserockimport/exts/python.to_lorry
+++ b/baserockimport/exts/python.to_lorry
@@ -28,7 +28,7 @@ import shutil
 import tempfile
 import xmlrpclib
 import logging
-import select
+import yaml
 
 import pkg_resources
 
@@ -109,9 +109,8 @@ def get_compression(url):
     return None
 
 # Assumption: url passed to this function must have a 'standard' tar extension
-def make_tarball_lorry(package_name, url):
-    # TODO: this prefix probably shouldn't be hardcoded here either
-    name = 'python-packages/%s' % package_name.lower()
+def make_tarball_lorry(lorry_prefix, package_name, url):
+    name = '%s/%s' % (lorry_prefix, package_name.lower())
 
     lorry = {'type': 'tarball', 'url': url}
     compression = get_compression(url)
@@ -138,7 +137,7 @@ def get_releases(client, requirement):
 
     return releases
 
-def generate_tarball_lorry(client, requirement):
+def generate_tarball_lorry(lorry_prefix, client, requirement):
     releases = get_releases(client, requirement)
 
     if len(releases) == 0:
@@ -178,43 +177,53 @@ def generate_tarball_lorry(client, requirement):
 
     url = urls[0]['url']
 
-    return make_tarball_lorry(requirement.project_name, url)
+    return make_tarball_lorry(lorry_prefix, requirement.project_name, url)
 
-def str_repo_lorry(package_name, repo_type, url):
-    # TODO: this prefix probably shouldn't be hardcoded here
-    name = 'python-packages/%s' % package_name.lower()
+def str_repo_lorry(lorry_prefix, package_name, repo_type, url):
+    name = '%s/%s' % (lorry_prefix, package_name.lower())
 
     return json.dumps({name: {'type': repo_type, 'url': url}},
                       indent=4, sort_keys=True)
 
-def main():
-    if len(sys.argv) != 2:
-        # TODO explain the format of python requirements
-        # warn the user that they probably want to quote their arg
-        # > < will be interpreted as redirection by the shell
-        print('usage: %s requirement' % sys.argv[0], file=sys.stderr)
-        sys.exit(1)
+class PythonLorryExtension(ImportExtension):
 
-    client = xmlrpclib.ServerProxy(PYPI_URL)
+    def __init__(self):
+        super(PythonLorryExtension, self).__init__()
 
-    req = pkg_resources.parse_requirements(sys.argv[1]).next()
+    def run(self):
+        if len(sys.argv) != 2:
+            # TODO explain the format of python requirements
+            # warn the user that they probably want to quote their arg
+            # > < will be interpreted as redirection by the shell
+            print('usage: %s requirement' % sys.argv[0], file=sys.stderr)
+            sys.exit(1)
 
-    new_proj_name = name_or_closest(client, req.project_name)
+        client = xmlrpclib.ServerProxy(PYPI_URL)
 
-    if new_proj_name == None:
-        error("Couldn't find any project with name '%s'" % req.project_name)
+        req = pkg_resources.parse_requirements(sys.argv[1]).next()
 
-    logging.debug('Treating %s as %s' % (req.project_name, new_proj_name))
-    req.project_name = new_proj_name
+        with open(self.local_data_path('python.yaml')) as f:
+            lorry_prefix = yaml.load(f)['lorry-prefix']
 
-    metadata = fetch_package_metadata(req.project_name)
-    info = metadata['info']
+        new_proj_name = name_or_closest(client, req.project_name)
 
-    repo_type = (find_repo_type(info['home_page'])
-                 if 'home_page' in info else None)
+        if new_proj_name == None:
+            error("Couldn't find any project with name '%s'" % req.project_name)
 
-    print(str_repo_lorry(req.project_name, repo_type, info['home_page'])
-            if repo_type else generate_tarball_lorry(client, req))
+        logging.debug('Treating %s as %s' % (req.project_name, new_proj_name))
+        req.project_name = new_proj_name
+
+        metadata = fetch_package_metadata(req.project_name)
+        info = metadata['info']
+
+        repo_type = (find_repo_type(info['home_page'])
+                     if 'home_page' in info else None)
+
+        if repo_type:
+            print(str_repo_lorry(lorry_prefix, req.project_name,
+                                 repo_type, info['home_page']))
+        else:
+            print(generate_tarball_lorry(lorry_prefix, client, req))
 
 if __name__ == '__main__':
-    PythonExtension().run()
+    PythonLorryExtension().run()