EasyInstall can now download bare ``.py`` files and wrap them in an egg,

as long as you include an ``#egg=name-version`` suffix on the URL, or if
the ``.py`` file is listed as the "Download URL" on the project's PyPI
page.  This allows third parties to "package" trivial Python modules
just by linking to them (e.g. from within their own PyPI page or
download links page).

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4041995

1 files changed, 83 insertions, 31 deletions

diff --git a/setuptools/package_index.py b/setuptools/package_index.py
index 964e3c1c..869fa7b0 100755
--- a/setuptools/package_index.py
+++ b/setuptools/package_index.py
@@ -1,6 +1,6 @@
 """PyPI and direct package downloading"""
 
-import sys, os.path, re, urlparse, urllib2
+import sys, os.path, re, urlparse, urllib2, shutil
 from pkg_resources import *
 from distutils import log
 from distutils.errors import DistutilsError
@@ -39,12 +39,15 @@ def parse_bdist_wininst(name):
 
     return base,py_ver
 
-def distros_for_url(url, metadata=None):
-    """Yield egg or source distribution objects that might be found at a URL"""
-
+def egg_info_for_url(url):
     scheme, server, path, parameters, query, fragment = urlparse.urlparse(url)
     base = urllib2.unquote(path.split('/')[-1])
     if '#' in base: base, fragment = base.split('#',1)
+    return base,fragment
+
+def distros_for_url(url, metadata=None):
+    """Yield egg or source distribution objects that might be found at a URL"""
+    base, fragment = egg_info_for_url(url)
     dists = distros_for_location(url, base, metadata)
     if fragment and not dists:
         match = EGG_FRAGMENT.match(fragment)
@@ -54,12 +57,10 @@ def distros_for_url(url, metadata=None):
             )
     return dists
 
-
 def distros_for_location(location, basename, metadata=None):
     """Yield egg or source distribution objects based on basename"""
     if basename.endswith('.egg.zip'):
         basename = basename[:-4]    # strip the .zip
-
     if basename.endswith('.egg'):   # only one, unambiguous interpretation
         return [Distribution.from_location(location, basename, metadata)]
 
@@ -76,7 +77,6 @@ def distros_for_location(location, basename, metadata=None):
         if basename.endswith(ext):
             basename = basename[:-len(ext)]
             return interpret_distro_name(location, basename, metadata)
-
     return []  # no extension matched
 
 
@@ -205,7 +205,6 @@ class PackageIndex(Environment):
 
     def process_index(self,url,page):
         """Process the contents of a PyPI page"""
-
         def scan(link):
             # Process a URL to see if it's for a package page
             if link.startswith(self.index_url):
@@ -217,14 +216,15 @@ class PackageIndex(Environment):
                     pkg = safe_name(parts[0])
                     ver = safe_version(parts[1])
                     self.package_pages.setdefault(pkg.lower(),{})[link] = True
+                    return to_filename(pkg), to_filename(ver)
+            return None, None
 
         if url==self.index_url or 'Index of Packages</title>' in page:
             # process an index page into the package-page index
             for match in HREF.finditer(page):
                 scan( urlparse.urljoin(url, match.group(1)) )
-
         else:
-            scan(url)   # ensure this page is in the page index
+            pkg,ver = scan(url)   # ensure this page is in the page index
             # process individual package page
             for tag in ("<th>Home Page", "<th>Download URL"):
                 pos = page.find(tag)
@@ -232,35 +232,44 @@ class PackageIndex(Environment):
                     match = HREF.search(page,pos)
                     if match:
                         # Process the found URL
-                        self.scan_url(urlparse.urljoin(url, match.group(1)))
-
+                        new_url = urlparse.urljoin(url, match.group(1))
+                        base, frag = egg_info_for_url(new_url)
+                        if base.endswith('.py') and not frag:
+                            if pkg and ver:
+                                new_url+='#egg=%s-%s' % (pkg,ver)
+                            else:
+                                self.need_version_info(url)
+                        self.scan_url(new_url)
         return PYPI_MD5.sub(
             lambda m: '<a href="%s#md5=%s">%s</a>' % m.group(1,3,2), page
         )
 
+    def need_version_info(self, url):
+        self.scan_all(
+            "Page at %s links to .py file(s) without version info; an index "
+            "scan is required.", url
+        )
 
-
-
-
-
+    def scan_all(self, msg, *args):
+        if self.index_url not in self.fetched_urls:
+            if msg: self.warn(msg,*args)
+            self.warn(
+                "Scanning index of all packages (this may take a while)"
+            )
+        self.scan_url(self.index_url)
 
     def find_packages(self, requirement):
         self.scan_url(self.index_url + requirement.unsafe_name+'/')
         if not self.package_pages.get(requirement.key):
             # Fall back to safe version of the name
             self.scan_url(self.index_url + requirement.project_name+'/')
-
         if not self.package_pages.get(requirement.key):
             # We couldn't find the target package, so search the index page too
             self.warn(
                 "Couldn't find index page for %r (maybe misspelled?)",
                 requirement.unsafe_name
             )
-            if self.index_url not in self.fetched_urls:
-                self.warn(
-                    "Scanning index of all packages (this may take a while)"
-                )
-            self.scan_url(self.index_url)
+            self.scan_all()
 
         for url in self.package_pages.get(requirement.key,()):
             # scan each page that might be related to the desired package
@@ -274,6 +283,8 @@ class PackageIndex(Environment):
             self.debug("%s does not match %s", requirement, dist)
         return super(PackageIndex, self).obtain(requirement,installer)
 
+
+
     def check_md5(self, cs, info, filename, tfp):
         if re.match('md5=[0-9a-f]{32}$', info):
             self.debug("Validating md5 checksum for %s", filename)
@@ -290,7 +301,10 @@ class PackageIndex(Environment):
 
         `spec` may be a ``Requirement`` object, or a string containing a URL,
         an existing local filename, or a project/version requirement spec
-        (i.e. the string form of a ``Requirement`` object).
+        (i.e. the string form of a ``Requirement`` object).  If it is the URL
+        of a .py file with an unambiguous ``#egg=name-version`` tag (i.e., one
+        that escapes ``-`` as ``_`` throughout), a trivial ``setup.py`` is
+        automatically created alongside the downloaded file.
 
         If `spec` is a ``Requirement`` object or a string containing a
         project/version requirement spec, this method is equivalent to
@@ -304,8 +318,11 @@ class PackageIndex(Environment):
             scheme = URL_SCHEME(spec)
             if scheme:
                 # It's a url, download it to tmpdir
-                return self._download_url(scheme.group(1), spec, tmpdir)
-
+                found = self._download_url(scheme.group(1), spec, tmpdir)
+                base, fragment = egg_info_for_url(spec)
+                if base.endswith('.py'):
+                    found = self.gen_setup(found,fragment,tmpdir)
+                return found
             elif os.path.exists(spec):
                 # Existing file or directory, just return it
                 return spec
@@ -317,15 +334,9 @@ class PackageIndex(Environment):
                         "Not a URL, existing file, or requirement spec: %r" %
                         (spec,)
                     )
-
         return self.fetch(spec, tmpdir)
 
 
-
-
-
-
-
     def fetch(self, requirement, tmpdir, force_scan=False, source=False):
         """Obtain a file suitable for fulfilling `requirement`
 
@@ -367,6 +378,47 @@ class PackageIndex(Environment):
         return dist
 
 
+    def gen_setup(self, filename, fragment, tmpdir):
+        match = EGG_FRAGMENT.match(fragment); #import pdb; pdb.set_trace()
+        dists = match and [d for d in
+            interpret_distro_name(filename, match.group(1), None) if d.version
+        ] or []
+
+        if len(dists)==1:   # unambiguous ``#egg`` fragment
+            basename = os.path.basename(filename)
+
+            # Make sure the file has been downloaded to the temp dir.
+            if os.path.dirname(filename) != tmpdir:
+                dst = os.path.join(tmpdir, basename)
+                from setuptools.command.easy_install import samefile
+                if not samefile(filename, dst):
+                    shutil.copy2(filename, dst)
+                    filename=dst
+
+            file = open(os.path.join(tmpdir, 'setup.py'), 'w')
+            file.write(
+                "from setuptools import setup\n"
+                "setup(name=%r, version=%r, py_modules=[%r])\n"
+                % (
+                    dists[0].project_name, dists[0].version,
+                    os.path.splitext(basename)[0]
+                )
+            )
+            file.close()
+            return filename
+
+        elif match:
+            raise DistutilsError(
+                "Can't unambiguously interpret project/version identifier %r; "
+                "any dashes in the name or version should be escaped using "
+                "underscores. %r" % (fragment,dists)
+            )
+        else:
+            raise DistutilsError(
+                "Can't process plain .py files without an '#egg=name-version'"
+                " suffix to enable automatic setup script generation."
+            )
+        
     dl_blocksize = 8192
     def _download_to(self, url, filename):
         self.url_ok(url,True)   # raises error if not allowed