Merge pull request #1510 from dstufft/use-zip-get-pip

Use a ZipFile as the get-pip.py script

contrib/build-installer

@@ -1,31 +1,164 @@
 #!/usr/bin/env python
-
+import base64
 import os
 import sys
-from packager import generate_script
+import zipfile
+
+WRAPPER_SCRIPT = b"""
+#!/usr/bin/env python
+#
+# Hi There!
+# You may be wondering what this giant blob of binary data here is, you might
+# even be worried that we're up to something nefarious (good for you for being
+# paranoid!). This is a base4 encoding of a zip file, this zip file contains
+# an entire copy of pip.
+#
+# Pip is a thing that installs packages, pip itself is a package that someone
+# might want to install, especially if they're looking to run this get-pip.py
+# script. Pip has a lot of code to deal with the security of installing
+# packages, various edge cases on various platforms, and other such sort of
+# "tribal knowledge" that has been encoded in it's code base. Because of this
+# we basically include an entire copy of pip inside this blob. We do this
+# because the alternatives are attempt to implement a "minipip" that probably
+# doesn't do things correctly and has weird edge cases, or compress pip itself
+# down into a single file.
+#
+# If you're wondering how this is created, the secret is
+# "contrib/build-installer" from the pip repository.
+
+ZIPFILE = b\"\"\"
+{zipfile}
+\"\"\"
+
+import base64
+import os.path
+import pkgutil
+import shutil
+import sys
+import tempfile
+
+
+def bootstrap(tmpdir=None):
+    # Import pip so we can use it to install pip and maybe setuptools too
+    import pip
 
-here = os.path.dirname(os.path.abspath(__file__))
-file_name = os.path.join(here, 'get-pip.py')
+    # We always want to install pip
+    packages = ["pip"]
+
+    # Check if the user has requested us not to install setuptools
+    if "--no-setuptools" in sys.argv or os.environ.get("PIP_NO_SETUPTOOLS"):
+        args = [x for x in sys.argv[1:] if x != "--no-setuptools"]
+    else:
+        args = sys.argv[1:]
+
+        # We want to see if setuptools is available before attempting to
+        # install it
+        try:
+            import setuptools
+        except ImportError:
+            packages += ["setuptools"]
+
+    delete_tmpdir = False
+    try:
+        # Create a temporary directory to act as a working directory if we were
+        # not given one.
+        if tmpdir is None:
+            tmpdir = tempfile.mkdtemp()
+            delete_tmpdir = True
+
+        # We need to extract the SSL certificates from requests so that they
+        # can be passed to --cert
+        cert_path = os.path.join(tmpdir, "cacert.pem")
+        with open(cert_path, "wb") as cert:
+            cert.write(pkgutil.get_data("pip._vendor.requests", "cacert.pem"))
+
+        # Use an environment variable here so that users can still pass
+        # --cert via sys.argv
+        os.environ.setdefault("PIP_CERT", cert_path)
+
+        # Execute the included pip and use it to install the latest pip and
+        # setuptools from PyPI
+        sys.exit(pip.main(["install", "--upgrade"] + packages + args))
+    finally:
+        # Remove our temporary directory
+        if delete_tmpdir and tmpdir:
+            shutil.rmtree(tmpdir, ignore_errors=True)
 
-entry = """
-import pip
-pip.bootstrap()
-"""
 
 def main():
-    sys.stdout.write("Creating pip bootstrapper...")
-    script = generate_script(entry, ['pip'])
-    f = open(file_name, 'w')
+    tmpdir = None
     try:
-        f.write(script)
+        # Create a temporary working directory
+        tmpdir = tempfile.mkdtemp()
+
+        # Unpack the zipfile into the temporary directory
+        pip_zip = os.path.join(tmpdir, "pip.zip")
+        with open(pip_zip, "wb") as fp:
+            fp.write(base64.decodestring(ZIPFILE))
+
+        # Add the zipfile to sys.path so that we can import it
+        sys.path = [pip_zip] + sys.path
+
+        # Run the bootstrap
+        bootstrap(tmpdir=tmpdir)
     finally:
-        f.close()
-    sys.stdout.write('done.\n')
-    if hasattr(os, 'chmod'):
-        oldmode = os.stat(file_name).st_mode & 07777
-        newmode = (oldmode | 0555) & 07777
-        os.chmod(file_name, newmode)
-        sys.stdout.write('Made resulting file %s executable.\n\n' % file_name)
-
-if __name__ == '__main__':
+        # Clean up our temporary working directory
+        if tmpdir:
+            shutil.rmtree(tmpdir, ignore_errors=True)
+
+
+if __name__ == "__main__":
+    main()
+""".lstrip()
+
+
+def getmodname(rootpath, path):
+    parts = path.split(os.sep)[len(rootpath.split(os.sep)):]
+    return '/'.join(parts)
+
+
+def main():
+    sys.stdout.write("Creating pip bootstrapper...")
+
+    here = os.path.dirname(os.path.abspath(__file__))
+    toplevel = os.path.dirname(here)
+    get_pip = os.path.join(here, "get-pip.py")
+
+    # Get all of the files we want to add to the zip file
+    all_files = []
+    for root, dirs, files in os.walk(os.path.join(toplevel, "pip")):
+        for pyfile in files:
+            if os.path.splitext(pyfile)[1] in {".py", ".pem", ".cfg", ".exe"}:
+                all_files.append(
+                    getmodname(toplevel, os.path.join(root, pyfile))
+                )
+
+    with zipfile.ZipFile(get_pip, "w", compression=zipfile.ZIP_DEFLATED) as z:
+        # Write the pip files to the zip archive
+        for filename in all_files:
+            z.write(os.path.join(toplevel, filename), filename)
+
+    # Get the binary data that compromises our zip file
+    with open(get_pip, "rb") as fp:
+        data = fp.read()
+
+    # Write out the wrapper script that will take the place of the zip script
+    # The reason we need to do this instead of just directly executing the
+    # zip script is that while Python will happily execute a zip script if
+    # passed it on the file system, it will not however allow this to work if
+    # passed it via stdin. This means that this wrapper script is required to
+    # make ``curl https://...../get-pip.py | python`` continue to work.
+    with open(get_pip, "wb") as fp:
+        fp.write(WRAPPER_SCRIPT.format(zipfile=base64.encodestring(data)))
+
+    # Ensure the permissions on the newly created file
+    if hasattr(os, "chmod"):
+        oldmode = os.stat(get_pip).st_mode & 0o7777
+        newmode = (oldmode | 0o555) & 0o7777
+        os.chmod(get_pip, newmode)
+
+    sys.stdout.write("done.\n")
+
+
+if __name__ == "__main__":
     main()