Feat/flavor form urllib (#403)

* Use URLLIB. Prepare to parse generator as well.

The latter uses global variables to store the state.
The idea is that we can be invoked either way, parsing
a flavor name (and generating a spec and a pretty description)
or parsing the specs (and generating the name from it).

* Avoid script injection.

* Avoid any HTML tags in flavor name.

* Appease flake8

Signed-off-by: Kurt Garloff <[email protected]>

Tests/iaas/flavor-naming/flavor-form.py

@@ -12,43 +12,55 @@
 or a human-readable description of the flavor.
 """
 
-# import os
+import os
 import sys
 import re
-# import traceback
-# TODO: Replace cgi by urllib, cgi is deprecated
-import cgi
+import urllib.parse
+import importlib
+fnmck = importlib.import_module("flavor-name-check")
 
+# Global variables
+FLAVOR_NAME = ""
+FLAVOR_SPEC = ()
+ERROR = ""
 
-class TestForm:
-    "Class for testing via cmd line"
-    def __init__(self, fnm):
-        self.value = fnm
+
+def parse_name(fnm):
+    "return tuple with flavor description"
+    global FLAVOR_SPEC, FLAVOR_NAME, ERROR
+    # Sanitize
+    # fnm = re.sub(r"<( *script)", r"<!--\1", fnm, flags=re.I)
+    fnm = re.sub(r"<", r"&lt;", fnm)
+    fnm = re.sub(r">", r"&gt;", fnm)
+    FLAVOR_NAME = fnm
+    try:
+        FLAVOR_SPEC = fnmck.parsename(fnm)
+    except (TypeError, NameError, KeyError) as exc:
+        ERROR = f"\tERROR<br/>\n\t{exc}"
+        return ()
+    ERROR = ""
+    return FLAVOR_SPEC
 
 
-def parse_form(form):
+def output_parse():
     "output pretty description from SCS flavor name"
-    import importlib
     fnmd = importlib.import_module("flavor-name-describe")
-    fnm = ""
-    try:
-        fnm = form["flavor"].value
-    except KeyError:
-        pass
     print('\t<br/>\n\t<FORM ACTION="/cgi-bin/flavor-form.py" METHOD="GET">')
-    print(f'\t  Flavor name: <INPUT TYPE="text" NAME="flavor" SIZE=24 VALUE="{fnm}"/>')
+    print(f'\t  Flavor name: <INPUT TYPE="text" NAME="flavor" SIZE=24 VALUE="{FLAVOR_NAME}"/>')
     print('\t  <INPUT TYPE="submit" VALUE="Submit"/>')
     # print('  <INPUT TYPE="reset"  VALUE="Clear"/>\n</FORM>')
     print('\t</FORM>')
-    if fnm:
-        print("\t<br/><b>Flavor</b>")
-        try:
-            fnmd.main((fnm,))
-        except (TypeError, NameError, KeyError) as exc:
-            print(f"\tERROR<br/>\n\t{exc}")
+    if FLAVOR_NAME:
+        print(f"\t<br/><b>Flavor {FLAVOR_NAME}:</b>")
+        if FLAVOR_SPEC:
+            print(f"\t{fnmd.prettyname(FLAVOR_SPEC)}")
+        else:
+            print("\tNot an SCS flavor")
+            if ERROR:
+                print(f"\t<br/>{ERROR})")
 
 
-def parse_generate(form):
+def output_generate():
     "input details to generate SCS flavor name"
     print("\tNot implemented yet as webform, use")
     print('\t<tt><a href="https://github.com/SovereignCloudStack/standards/blob/main/Tests/iaas/flavor-naming/flavor-name-check.py">flavor-name-check.py</a> -i</tt>')
@@ -57,19 +69,23 @@ def parse_generate(form):
 def main(argv):
     "Entry point for cgi flavor parsing"
     print("Content-Type: text/html\n")
-    form = cgi.FieldStorage()
+    form = {"flavor": [""]}
+    if 'QUERY_STRING' in os.environ:
+        form = urllib.parse.parse_qs(os.environ['QUERY_STRING'])
     # For testing
     if len(argv) > 0:
-        form = {"flavor": TestForm(argv[0])}
+        form = {"flavor": [argv[0],]}
     find_parse    = re.compile(r'^[ \t]*<!\-\-FLAVOR\-FORM: PARSE\-\->[ \t]*$')
     find_generate = re.compile(r'^[ \t]*<!\-\-FLAVOR\-FORM: GENERATE\-\->[ \t]*$')
+    if "flavor" in form:
+        parse_name(form["flavor"][0])
     with open("page/index.html", "r", encoding='utf-8') as infile:
         for line in infile:
             print(line, end='')
             if find_parse.match(line):
-                parse_form(form)
+                output_parse()
             elif find_generate.match(line):
-                parse_generate(form)
+                output_generate()
 
 
 if __name__ == "__main__":