Add SSL/SNI diagnostics script.

contrib/sni_test.py

@@ -0,0 +1,145 @@
+#!/usr/bin/env python
+
+import os
+import sys
+
+# Ensure that we use the Headphones provided libraries.
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "../lib"))
+
+import urlparse
+
+
+def can_import(module):
+    """
+    Return True if a given module can be imported or not.
+    """
+
+    try:
+        __import__(module)
+    except ImportError:
+        return False
+
+    # Module can be imported
+    return True
+
+
+def check_installation():
+    """
+    Check if some core modules are available. Info is based on this topic:
+    https://github.com/rembo10/headphones/issues/2210.
+    """
+
+    if can_import("requests"):
+        import requests
+        requests_version = requests.__version__
+    else:
+        requests_version = "no"
+
+    if can_import("OpenSSL"):
+        import OpenSSL
+        openssl_version = OpenSSL.__version__
+    else:
+        openssl_version = "no"
+
+    if can_import("cryptography"):
+        import cryptography
+        cryptography_version = cryptography.__version__
+    else:
+        cryptography_version = "no"
+
+    if can_import("pyasn1"):
+        import pyasn1
+        pyasn1_version = pyasn1.__version__
+    else:
+        pyasn1_version = "no"
+
+    if can_import("ndg.httpsclient"):
+        from ndg import httpsclient
+        ndg_version = httpsclient.__date__
+    else:
+        ndg_version = "no"
+
+    # Print some system information.
+    sys.stdout.write(
+        "* Checking Python version: %s.%s.%s\n" % sys.version_info[:3])
+    sys.stdout.write("* Operating system: %s\n" % sys.platform)
+
+    sys.stdout.write(
+        "* Checking if requests can be imported: %s\n" % requests_version)
+    sys.stdout.write(
+        "* Checking if pyOpenSSL is installed: %s\n" % openssl_version)
+    sys.stdout.write(
+        "* Checking if cryptography is installed: %s\n" % cryptography_version)
+    sys.stdout.write(
+        "* Checking if pyasn1 is installed: %s\n" % pyasn1_version)
+    sys.stdout.write(
+        "* Checking if ndg.httpsclient is installed: %s\n" % ndg_version)
+
+
+def main():
+    """
+    Test if the current Headphones installation can connect to SNI-enabled
+    servers.
+    """
+
+    # Read the URL to test.
+    if len(sys.argv) == 1:
+        url = "https://sni.velox.ch/"
+    else:
+        url = sys.argv[1]
+
+    # Check if it is a HTTPS website.
+    parts = urlparse.urlparse(url)
+
+    if parts.scheme.lower() != "https":
+        sys.stderr.write(
+            "Error: provided URL does not start with https://\n")
+        return 1
+
+    # Gather information
+    check_installation()
+
+    # Do the request.
+    if not can_import("requests"):
+        sys.stderr.exit("Error: cannot continue without requests module!\n")
+        return 1
+
+    sys.stdout.write("* Performing request: %s\n" % url)
+
+    import requests
+    requests.packages.urllib3.disable_warnings()
+
+    try:
+        try:
+            response = requests.get(url)
+        except requests.exceptions.SSLError as e:
+            sys.stdout.write(
+                "- Server certificate seems invalid. I will disable "
+                "certificate check and try again. You'll see the real "
+                "exception if it fails again.\n")
+            sys.stdout.write(
+                "* Retrying request with certificate verification off.\n")
+            response = requests.get(url)
+    except Exception as e:
+        sys.stdout.write(
+            "- An error occured while performing the request. The "
+            "exception was: %s\n" % e.message)
+        sys.stdout.write(
+            "- Consult the Troubleshooting wiki (https://github.com/"
+            "rembo10/headphones/wiki/Troubleshooting) before you post an "
+            "issue!")
+        return 0
+
+    # Verify the response.
+    if response.status_code == 200:
+        sys.stdout.write("+ Got a valid response. All seems OK!\n")
+    else:
+        sys.stdout.write(
+            "- Server returned status code %s. Expected a status code 200.\n",
+            response.status_code)
+        sys.stdout.write(
+            "- However, I was able to communicate to the server!\n")
+
+# E.g. `python sni_test.py https://example.org'.
+if __name__ == "__main__":
+    sys.exit(main())