Python 3.4 compatible for ROS usage

.github/validate-rapps.py

@@ -45,6 +45,12 @@
     b'ppc',
 ]
 
+LICENSE_TYPES = [
+    1, # Open source
+    2, # Freeware
+    3, # Trial/Demo
+]
+
 
 all_names = {}
 all_urls = {}
@@ -66,7 +72,7 @@ def __init__(self):
 
     def add(self, line, column, problem):
         self._problems += 1
-        print(f'{line.location(column)}: {problem}')
+        print('{col}: {msg}'.format(col = line.location(column), msg = problem))
         print(line.text())
         idx = column - 1 + len("b'")    # Offset the b' prefix
         print(' ' * idx + '^')
@@ -125,17 +131,19 @@ def _parse_section(self, reporter, stripped):
 
         if section_name != b'Section':
             help = 'should always be "Section"'
-            reporter.add(self, self._text.index(section_name) + 1, f'Invalid section name: "{section_name}", {help}')
+            reporter.add(self, self._text.index(section_name) + 1,
+                         'Invalid section name: "{sec}", {msg}'.format(sec = section_name, msg = help))
         elif not locale:
             self.main_section = True
 
         if locale:
             if len(locale) not in (2, 4) or not all(c in HEXDIGITS for c in locale):
-                reporter.add(self, self._text.index(locale) + 1, f'Invalid locale{extra_locale}: "{locale}"')
+                reporter.add(self, self._text.index(locale) + 1,
+                             'Invalid locale{extra}: "{loc}"'.format(extra = extra_locale, loc = locale))
 
         if arch:
             if arch not in ALL_ARCH:
-                reporter.add(self, self._text.index(arch) + 1, f'Unknown architecture: "{arch}"')
+                reporter.add(self, self._text.index(arch) + 1, 'Unknown architecture: "%s"' % arch)
 
     def _extract_section_info(self, text, reporter):
         text = text[1:-1]
@@ -152,26 +160,40 @@ def _extract_section_info(self, text, reporter):
             else:
                 locale = parts[1]
                 arch = None
-                extra_locale = '(and unknown architecture)'
+                extra_locale = ' (and unknown architecture)'
         elif len(parts) == 3:
             locale = parts[1]
             arch = parts[2]
         else:
             locale = arch = None
-            reporter.add(self, self._text.index(b'[') + 1, f'Unknown section format: "{text}"')
+            reporter.add(self, self._text.index(b'[') + 1, 'Unknown section format: "%s"' % text)
         return section_name, locale, extra_locale, arch
 
     def _parse_key_value(self, reporter, parts):
         # key = value
         assert len(parts) == 2, self
         self.key = parts[0]
         self.val = parts[1]
+        textkey = self.key.decode()
+        textval = self.val.decode()
 
         if self.key not in ALL_KEYS:
-            reporter.add(self, 0, f'Unknown key: "{self.key}"')
+            reporter.add(self, 0, 'Unknown key: "{key}"'.format(key = textkey))
+
+        if self.key in [b'LicenseType']:
+            v = int(textval, base=10)
+            if v not in LICENSE_TYPES:
+                reporter.add(self, 0, 'Invalid value: "{val}" in {key}'.format(val = v, key = textkey))
+
+        if self.key in [b'License']:
+            v = textval
+            if v.casefold() == 'Unknown'.casefold():
+                # TODO: Reporter should be enabled when the existing DB entries are fixed:
+                # reporter.add(self, 0, 'Invalid value: "{val}" in {key}'.format(val = v, key = textkey))
+                print('Warning: {key} is "{val}" ({file})'.format(val = v, key = textkey, file = self._file.filename))
 
     def location(self, column):
-        return f'{self._file.filename}({self._lineno}:{column})'
+        return '{file}({line}:{col})'.format(file = self._file.filename, line = self._lineno, col = column)
 
     def text(self):
         return self._text
@@ -216,7 +238,7 @@ def parse(self, reporter):
                 main_section = section
                 for key in REQUIRED_KEYS:
                     if not section[key]:
-                        reporter.add(section, 0, f'Main section has no {key} key!')
+                        reporter.add(section, 0, 'Main section has no {key} key!'.format(key = key))
             if section[b'URLDownload'] and not section[b'SizeBytes']:
                 # We allow this, if the main section has a SizeBytes (alternate mirror without duplicating the info)
                 if section == main_section or main_section and not main_section[b'SizeBytes']:
@@ -246,7 +268,7 @@ def parse(self, reporter):
 def verify_unique(reporter, lines, line, name):
     first = lines.get(name, None)
     if first:
-        reporter.add(line, 0, f'Duplicate value found: {name}')
+        reporter.add(line, 0, 'Duplicate value found: {name}'.format(name = name))
         reporter.add(first, 0, 'First occurence:')
     else:
         lines[name] = line