From: W. Trevor King <wking@tremily.us>
Date: Tue, 12 Nov 2013 18:02:23 +0000 (-0800)
Subject: swc-windows-installer.py: Split out zip_install into its own function
X-Git-Tag: v0.1~23
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=f374519f66c90132cf9dfc53a782533f0639f52d;p=swc-setup-windows-installer.git

swc-windows-installer.py: Split out zip_install into its own function

This makes it easy to install other packages besides nano.  I've also
added SHA1 checks to avoid installing packages that don't match the
expected hash.  This lets us trust ZipFile.extractall instead of
extracting from a hard-coded list of approved files.
---

diff --git a/swc-windows-installer.py b/swc-windows-installer.py
index 1ecd714..1904bbb 100755
--- a/swc-windows-installer.py
+++ b/swc-windows-installer.py
@@ -20,6 +20,7 @@ To use:
 
 """
 
+import hashlib
 try:  # Python 3
     from io import BytesIO as _BytesIO
 except ImportError:  # Python 2
@@ -32,17 +33,28 @@ except ImportError:  # Python 2
 import zipfile
 
 
+def zip_install(url, sha1, install_directory):
+    """Download and install a zipped bundle of compiled software"""
+    r = _urlopen(url)
+    zip_bytes = r.read()
+    download_sha1 = hashlib.sha1(zip_bytes).hexdigest()
+    if download_sha1 != sha1:
+        raise ValueError(
+            'downloaded {!r} has the wrong SHA1 hash: {} != {}'.format(
+                url, downloaded_sha1, sha1))
+    zip_io = _BytesIO(zip_bytes)
+    zip_file = zipfile.ZipFile(zip_io)
+    if not os.path.isdir(install_directory):
+        os.makedirs(install_directory)
+        zip_file.extractall(install_directory)
+
+
 def install_nano(install_directory):
     """Download and install the nano text editor"""
-    url = "http://www.nano-editor.org/dist/v2.2/NT/nano-2.2.6.zip"
-    r = _urlopen(url)
-    nano_zip_content = _BytesIO(r.read())
-    nano_zip = zipfile.ZipFile(nano_zip_content)
-    nano_files = ['nano.exe', 'cygwin1.dll', 'cygintl-8.dll',
-                  'cygiconv-2.dll', 'cyggcc_s-1.dll']
-    os.makedirs(install_directory)
-    for file_name in nano_files:
-        nano_zip.extract(file_name, install_directory)
+    zip_install(
+        url='http://www.nano-editor.org/dist/v2.2/NT/nano-2.2.6.zip',
+        sha1='f5348208158157060de0a4df339401f36250fe5b',
+        install_directory=install_directory)
 
 
 def create_nosetests_entry_point(python_scripts_directory):
@@ -89,7 +101,7 @@ def main():
     bin_dir = os.path.join(swc_dir, 'bin')
     create_nosetests_entry_point(python_scripts_directory=bin_dir)
     nano_dir = os.path.join(swc_dir, 'lib', 'nano')
-    install_nano(installation_directory=nano_dir)
+    install_nano(install_directory=nano_dir)
     update_bash_profile(extra_paths=(nano_dir, bin_dir))