Improvements to Fake Resolver

2 files changed, 221 insertions, 6 deletions

diff --git a/test/core/client_channel/resolvers/BUILD b/test/core/client_channel/resolvers/BUILD
index af37072e3a..e8361cdef6 100644
--- a/test/core/client_channel/resolvers/BUILD
+++ b/test/core/client_channel/resolvers/BUILD
@@ -32,20 +32,48 @@ licenses(["notice"])  # 3-clause BSD
 cc_test(
     name = "dns_resolver_connectivity_test",
     srcs = ["dns_resolver_connectivity_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_test(
     name = "dns_resolver_test",
     srcs = ["dns_resolver_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_test(
     name = "sockaddr_resolver_test",
     srcs = ["sockaddr_resolver_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
+)
+
+cc_test(
+    name = "fake_resolver_test",
+    srcs = ["fake_resolver_test.c"],
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/end2end:fake_resolver",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )
diff --git a/test/core/client_channel/resolvers/fake_resolver_test.c b/test/core/client_channel/resolvers/fake_resolver_test.c
new file mode 100644
index 0000000000..861918fbd6
--- /dev/null
+++ b/test/core/client_channel/resolvers/fake_resolver_test.c
@@ -0,0 +1,187 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/combiner.h"
+#include "src/core/lib/security/credentials/fake/fake_credentials.h"
+
+#include "test/core/end2end/fake_resolver.h"
+#include "test/core/util/test_config.h"
+
+static grpc_resolver *build_fake_resolver(
+    grpc_exec_ctx *exec_ctx, grpc_combiner *combiner,
+    grpc_fake_resolver_response_generator *response_generator) {
+  grpc_resolver_factory *factory = grpc_resolver_factory_lookup("test");
+  grpc_arg generator_arg =
+      grpc_fake_resolver_response_generator_arg(response_generator);
+  grpc_resolver_args args;
+  memset(&args, 0, sizeof(args));
+  grpc_channel_args channel_args = {1, &generator_arg};
+  args.args = &channel_args;
+  args.combiner = combiner;
+  grpc_resolver *resolver =
+      grpc_resolver_factory_create_resolver(exec_ctx, factory, &args);
+  grpc_resolver_factory_unref(factory);
+  return resolver;
+}
+
+typedef struct on_resolution_arg {
+  grpc_channel_args *resolver_result;
+  grpc_channel_args *expected_resolver_result;
+  bool was_called;
+} on_resolution_arg;
+
+void on_resolution_cb(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+  on_resolution_arg *res = arg;
+  res->was_called = true;
+  // We only check the addresses channel arg because that's the only one
+  // explicitly set by the test via
+  // grpc_fake_resolver_response_generator_set_response.
+  const grpc_lb_addresses *actual_lb_addresses =
+      grpc_lb_addresses_find_channel_arg(res->resolver_result);
+  const grpc_lb_addresses *expected_lb_addresses =
+      grpc_lb_addresses_find_channel_arg(res->expected_resolver_result);
+  GPR_ASSERT(
+      grpc_lb_addresses_cmp(actual_lb_addresses, expected_lb_addresses) == 0);
+  grpc_channel_args_destroy(exec_ctx, res->resolver_result);
+  grpc_channel_args_destroy(exec_ctx, res->expected_resolver_result);
+}
+
+static void test_fake_resolver() {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_combiner *combiner = grpc_combiner_create(NULL);
+  // Create resolver.
+  grpc_fake_resolver_response_generator *response_generator =
+      grpc_fake_resolver_response_generator_create();
+  grpc_resolver *resolver =
+      build_fake_resolver(&exec_ctx, combiner, response_generator);
+  GPR_ASSERT(resolver != NULL);
+
+  // Setup expectations.
+  grpc_uri *uris[] = {grpc_uri_parse(&exec_ctx, "ipv4:10.2.1.1:1234", true),
+                      grpc_uri_parse(&exec_ctx, "ipv4:127.0.0.1:4321", true)};
+  char *balancer_names[] = {"name1", "name2"};
+  const bool is_balancer[] = {true, false};
+  grpc_lb_addresses *addresses = grpc_lb_addresses_create(3, NULL);
+  for (size_t i = 0; i < GPR_ARRAY_SIZE(uris); ++i) {
+    grpc_lb_addresses_set_address_from_uri(
+        addresses, i, uris[i], is_balancer[i], balancer_names[i], NULL);
+    grpc_uri_destroy(uris[i]);
+  }
+  const grpc_arg addresses_arg =
+      grpc_lb_addresses_create_channel_arg(addresses);
+  grpc_channel_args *results =
+      grpc_channel_args_copy_and_add(NULL, &addresses_arg, 1);
+  grpc_lb_addresses_destroy(&exec_ctx, addresses);
+  on_resolution_arg on_res_arg;
+  memset(&on_res_arg, 0, sizeof(on_res_arg));
+  on_res_arg.expected_resolver_result = results;
+  grpc_closure *on_resolution = grpc_closure_create(
+      on_resolution_cb, &on_res_arg, grpc_combiner_scheduler(combiner, false));
+
+  // Set resolver results and trigger first resolution. on_resolution_cb
+  // performs the checks.
+  grpc_fake_resolver_response_generator_set_response(
+      &exec_ctx, response_generator, results);
+  grpc_resolver_next_locked(&exec_ctx, resolver, &on_res_arg.resolver_result,
+                            on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(on_res_arg.was_called);
+
+  // Setup update.
+  grpc_uri *uris_update[] = {
+      grpc_uri_parse(&exec_ctx, "ipv4:192.168.1.0:31416", true)};
+  char *balancer_names_update[] = {"name3"};
+  const bool is_balancer_update[] = {false};
+  grpc_lb_addresses *addresses_update = grpc_lb_addresses_create(1, NULL);
+  for (size_t i = 0; i < GPR_ARRAY_SIZE(uris_update); ++i) {
+    grpc_lb_addresses_set_address_from_uri(addresses_update, i, uris_update[i],
+                                           is_balancer_update[i],
+                                           balancer_names_update[i], NULL);
+    grpc_uri_destroy(uris_update[i]);
+  }
+
+  grpc_arg addresses_update_arg =
+      grpc_lb_addresses_create_channel_arg(addresses_update);
+  grpc_channel_args *results_update =
+      grpc_channel_args_copy_and_add(NULL, &addresses_update_arg, 1);
+  grpc_lb_addresses_destroy(&exec_ctx, addresses_update);
+
+  // Setup expectations for the update.
+  on_resolution_arg on_res_arg_update;
+  memset(&on_res_arg_update, 0, sizeof(on_res_arg_update));
+  on_res_arg_update.expected_resolver_result = results_update;
+  on_resolution = grpc_closure_create(on_resolution_cb, &on_res_arg_update,
+                                      grpc_combiner_scheduler(combiner, false));
+
+  // Set updated resolver results and trigger a second resolution.
+  grpc_fake_resolver_response_generator_set_response(
+      &exec_ctx, response_generator, results_update);
+  grpc_resolver_next_locked(&exec_ctx, resolver,
+                            &on_res_arg_update.resolver_result, on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(on_res_arg.was_called);
+
+  // Requesting a new resolution without re-senting the response shouldn't
+  // trigger the resolution callback.
+  memset(&on_res_arg, 0, sizeof(on_res_arg));
+  grpc_resolver_next_locked(&exec_ctx, resolver, &on_res_arg.resolver_result,
+                            on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(!on_res_arg.was_called);
+
+  GRPC_COMBINER_UNREF(&exec_ctx, combiner, "test_fake_resolver");
+  GRPC_RESOLVER_UNREF(&exec_ctx, resolver, "test_fake_resolver");
+  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_fake_resolver_response_generator_unref(response_generator);
+}
+
+int main(int argc, char **argv) {
+  grpc_test_init(argc, argv);
+  grpc_fake_resolver_init();  // Registers the "test" scheme.
+  grpc_init();
+
+  test_fake_resolver();
+
+  grpc_shutdown();
+  return 0;
+}