Add c-ares resolver tests against GCE DNS, using the unit test.

1 files changed, 101 insertions, 9 deletions

diff --git a/test/cpp/naming/gen_build_yaml.py b/test/cpp/naming/gen_build_yaml.py
index 3a51fef7a0..91718156e9 100755
--- a/test/cpp/naming/gen_build_yaml.py
+++ b/test/cpp/naming/gen_build_yaml.py
@@ -24,6 +24,12 @@ import json
 
 _LOCAL_DNS_SERVER_ADDRESS = '127.0.0.1:15353'
 
+_TARGET_RECORDS_TO_SKIP_AGAINST_GCE = [
+  # TODO: enable this once able to upload the very large TXT record
+  # in this group to GCE DNS.
+  'ipv4-config-causing-fallback-to-tcp',
+]
+
 def _append_zone_name(name, zone_name):
   return '%s.%s' % (name, zone_name)
 
@@ -33,21 +39,107 @@ def _build_expected_addrs_cmd_arg(expected_addrs):
     out.append('%s,%s' % (addr['address'], str(addr['is_balancer'])))
   return ';'.join(out)
 
+def _data_for_type(r_type, r_data, common_zone_name):
+  if r_type in ['A', 'AAAA']:
+    return ' '.join(map(lambda x: '\"%s\"' % x, r_data))
+  if r_type == 'SRV':
+    assert len(r_data) == 1
+    target = r_data[0].split(' ')[3]
+    uploadable_target = '%s.%s' % (target, common_zone_name)
+    uploadable = r_data[0].split(' ')
+    uploadable[3] = uploadable_target
+    return '\"%s\"' % ' '.join(uploadable)
+  if r_type == 'TXT':
+    assert len(r_data) == 1
+    chunks = []
+    all_data = r_data[0]
+    cur = 0
+    # Split TXT records that span more than 255 characters (the single
+    # string length-limit in DNS) into multiple strings. Each string
+    # needs to be wrapped with double-quotes, and all inner double-quotes
+    # are escaped. The wrapping double-quotes and inner backslashes can be
+    # counted towards the 255 character length limit (as observed with gcloud),
+    # so make sure all strings fit within that limit.
+    while len(all_data[cur:]) > 0:
+      next_chunk = '\"'
+      while len(next_chunk) < 254 and len(all_data[cur:]) > 0:
+        if all_data[cur] == '\"':
+          if len(next_chunk) < 253:
+            next_chunk += '\\\"'
+          else:
+            break
+        else:
+          next_chunk += all_data[cur]
+        cur += 1
+      next_chunk += '\"'
+      if len(next_chunk) > 255:
+        raise Exception('Bug: next chunk is too long.')
+      chunks.append(next_chunk)
+    # Wrap the whole record in single quotes to make sure all strings
+    # are associated with the same TXT record (to make it one bash token for
+    # gcloud)
+    return '\'%s\'' % ' '.join(chunks)
+
+# Convert DNS records from their "within a test group" format
+# of the yaml file to an easier form for the templates to use.
+def _gcloud_uploadable_form(test_cases, common_zone_name):
+  out = []
+  for group in test_cases:
+    if group['record_to_resolve'] in _TARGET_RECORDS_TO_SKIP_AGAINST_GCE:
+      continue
+    for record_name in group['records'].keys():
+      r_ttl = None
+      all_r_data = {}
+      for r_data in group['records'][record_name]:
+        # enforce records have the same TTL only for simplicity
+        if r_ttl is None:
+          r_ttl = r_data['TTL']
+        assert r_ttl == r_data['TTL'], '%s and %s differ' % (r_ttl, r_data['TTL'])
+        r_type = r_data['type']
+        if all_r_data.get(r_type) is None:
+          all_r_data[r_type] = []
+        all_r_data[r_type].append(r_data['data'])
+      for r_type in all_r_data.keys():
+        for r in out:
+          assert r['name'] != record_name or r['type'] != r_type, 'attempt to add a duplicate record'
+        out.append({
+            'name': record_name,
+            'ttl': r_ttl,
+            'type': r_type,
+            'data': _data_for_type(r_type, all_r_data[r_type], common_zone_name)
+        })
+  return out
+
+def _gce_dns_zone_id(resolver_component_data):
+  dns_name = resolver_component_data['resolver_tests_common_zone_name']
+  return dns_name.replace('.', '-') + 'zone-id'
+
+def _resolver_test_cases(resolver_component_data, records_to_skip):
+  out = []
+  for test_case in resolver_component_data['resolver_component_tests']:
+    if test_case['record_to_resolve'] in records_to_skip:
+      continue
+    out.append({
+      'target_name': _append_zone_name(test_case['record_to_resolve'],
+                                       resolver_component_data['resolver_tests_common_zone_name']),
+      'expected_addrs': _build_expected_addrs_cmd_arg(test_case['expected_addrs']),
+      'expected_chosen_service_config': (test_case['expected_chosen_service_config'] or ''),
+      'expected_lb_policy': (test_case['expected_lb_policy'] or ''),
+    })
+  return out
+
 def main():
   resolver_component_data = ''
   with open('test/cpp/naming/resolver_test_record_groups.yaml') as f:
     resolver_component_data = yaml.load(f)
 
   json = {
-      'resolver_component_test_cases': [
-          {
-              'target_name': _append_zone_name(test_case['record_to_resolve'],
-                                                 resolver_component_data['resolver_component_tests_common_zone_name']),
-              'expected_addrs': _build_expected_addrs_cmd_arg(test_case['expected_addrs']),
-              'expected_chosen_service_config': (test_case['expected_chosen_service_config'] or ''),
-              'expected_lb_policy': (test_case['expected_lb_policy'] or ''),
-          } for test_case in resolver_component_data['resolver_component_tests']
-      ],
+      'resolver_tests_common_zone_name': resolver_component_data['resolver_tests_common_zone_name'],
+      'resolver_gce_integration_tests_zone_id': _gce_dns_zone_id(resolver_component_data),
+      'all_integration_test_records': _gcloud_uploadable_form(resolver_component_data['resolver_component_tests'],
+                                                              resolver_component_data['resolver_tests_common_zone_name']),
+      'resolver_gce_integration_test_cases': _resolver_test_cases(resolver_component_data, _TARGET_RECORDS_TO_SKIP_AGAINST_GCE),
+      'resolver_component_test_cases': _resolver_test_cases(resolver_component_data, []),
       'targets': [
           {
               'name': 'resolver_component_test' + unsecure_build_config_suffix,