Refactor code for generating balancer channel args.
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
index 11163a5..e38211f 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
@@ -918,20 +918,31 @@
// helper code for creating balancer channel
//
-// Helper function to construct a target info entry.
-grpc_slice_hash_table_entry BalancerEntryCreate(const char* address,
- const char* balancer_name) {
- grpc_slice_hash_table_entry entry;
- entry.key = grpc_slice_from_copied_string(address);
- entry.value = gpr_strdup(balancer_name);
- return entry;
-}
-
-// Comparison function used for slice_hash_table vtable.
-int BalancerNameCmp(void* a, void* b) {
- const char* a_str = static_cast<const char*>(a);
- const char* b_str = static_cast<const char*>(b);
- return strcmp(a_str, b_str);
+grpc_lb_addresses* ExtractBalancerAddresses(
+ const grpc_lb_addresses* addresses) {
+ size_t num_grpclb_addrs = 0;
+ for (size_t i = 0; i < addresses->num_addresses; ++i) {
+ if (addresses->addresses[i].is_balancer) ++num_grpclb_addrs;
+ }
+ // There must be at least one balancer address, or else the
+ // client_channel would not have chosen this LB policy.
+ GPR_ASSERT(num_grpclb_addrs > 0);
+ grpc_lb_addresses* lb_addresses =
+ grpc_lb_addresses_create(num_grpclb_addrs, nullptr);
+ size_t lb_addresses_idx = 0;
+ for (size_t i = 0; i < addresses->num_addresses; ++i) {
+ if (!addresses->addresses[i].is_balancer) continue;
+ if (addresses->addresses[i].user_data != nullptr) {
+ gpr_log(GPR_ERROR,
+ "This LB policy doesn't support user data. It will be ignored");
+ }
+ grpc_lb_addresses_set_address(
+ lb_addresses, lb_addresses_idx++, addresses->addresses[i].address.addr,
+ addresses->addresses[i].address.len, false /* is balancer */,
+ addresses->addresses[i].balancer_name, nullptr /* user data */);
+ }
+ GPR_ASSERT(num_grpclb_addrs == lb_addresses_idx);
+ return lb_addresses;
}
/* Returns the channel args for the LB channel, used to create a bidirectional
@@ -946,51 +957,50 @@
const grpc_lb_addresses* addresses,
FakeResolverResponseGenerator* response_generator,
const grpc_channel_args* args) {
- size_t num_grpclb_addrs = 0;
- for (size_t i = 0; i < addresses->num_addresses; ++i) {
- if (addresses->addresses[i].is_balancer) ++num_grpclb_addrs;
- }
- // There must be at least one balancer address, or else the
- // client_channel would not have chosen this LB policy.
- GPR_ASSERT(num_grpclb_addrs > 0);
- grpc_lb_addresses* lb_addresses =
- grpc_lb_addresses_create(num_grpclb_addrs, nullptr);
- grpc_slice_hash_table_entry* targets_info_entries =
- (grpc_slice_hash_table_entry*)gpr_zalloc(sizeof(*targets_info_entries) *
- num_grpclb_addrs);
- size_t lb_addresses_idx = 0;
- for (size_t i = 0; i < addresses->num_addresses; ++i) {
- if (!addresses->addresses[i].is_balancer) continue;
- if (addresses->addresses[i].user_data != nullptr) {
- gpr_log(GPR_ERROR,
- "This LB policy doesn't support user data. It will be ignored");
- }
- char* addr_str;
- GPR_ASSERT(grpc_sockaddr_to_string(
- &addr_str, &addresses->addresses[i].address, true) > 0);
- targets_info_entries[lb_addresses_idx] =
- BalancerEntryCreate(addr_str, addresses->addresses[i].balancer_name);
- gpr_free(addr_str);
- grpc_lb_addresses_set_address(
- lb_addresses, lb_addresses_idx++, addresses->addresses[i].address.addr,
- addresses->addresses[i].address.len, false /* is balancer */,
- addresses->addresses[i].balancer_name, nullptr /* user data */);
- }
- GPR_ASSERT(num_grpclb_addrs == lb_addresses_idx);
- grpc_slice_hash_table* targets_info = grpc_slice_hash_table_create(
- num_grpclb_addrs, targets_info_entries, gpr_free, BalancerNameCmp);
- gpr_free(targets_info_entries);
- grpc_channel_args* lb_channel_args =
- grpc_lb_policy_grpclb_build_lb_channel_args(targets_info,
- response_generator, args);
- grpc_arg lb_channel_addresses_arg =
- grpc_lb_addresses_create_channel_arg(lb_addresses);
- grpc_channel_args* result = grpc_channel_args_copy_and_add(
- lb_channel_args, &lb_channel_addresses_arg, 1);
- grpc_slice_hash_table_unref(targets_info);
- grpc_channel_args_destroy(lb_channel_args);
+ grpc_lb_addresses* lb_addresses = ExtractBalancerAddresses(addresses);
+ // Channel args to remove.
+ static const char* args_to_remove[] = {
+ // LB policy name, since we want to use the default (pick_first) in
+ // the LB channel.
+ GRPC_ARG_LB_POLICY_NAME,
+ // The channel arg for the server URI, since that will be different for
+ // the LB channel than for the parent channel. The client channel
+ // factory will re-add this arg with the right value.
+ GRPC_ARG_SERVER_URI,
+ // The resolved addresses, which will be generated by the name resolver
+ // used in the LB channel. Note that the LB channel will use the fake
+ // resolver, so this won't actually generate a query to DNS (or some
+ // other name service). However, the addresses returned by the fake
+ // resolver will have is_balancer=false, whereas our own addresses have
+ // is_balancer=true. We need the LB channel to return addresses with
+ // is_balancer=false so that it does not wind up recursively using the
+ // grpclb LB policy, as per the special case logic in client_channel.c.
+ GRPC_ARG_LB_ADDRESSES,
+ // The fake resolver response generator, because we are replacing it
+ // with the one from the grpclb policy, used to propagate updates to
+ // the LB channel.
+ GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR,
+ };
+ // Channel args to add.
+ const grpc_arg args_to_add[] = {
+ // New LB addresses.
+ // Note that we pass these in both when creating the LB channel
+ // and via the fake resolver. The latter is what actually gets used.
+ grpc_lb_addresses_create_channel_arg(lb_addresses),
+ // The fake resolver response generator, which we use to inject
+ // address updates into the LB channel.
+ grpc_core::FakeResolverResponseGenerator::MakeChannelArg(
+ response_generator),
+ };
+ // Construct channel args.
+ grpc_channel_args* new_args = grpc_channel_args_copy_and_add_and_remove(
+ args, args_to_remove, GPR_ARRAY_SIZE(args_to_remove), args_to_add,
+ GPR_ARRAY_SIZE(args_to_add));
+ // Make any necessary modifications for security.
+ new_args = grpc_lb_policy_grpclb_modify_lb_channel_args(new_args);
+ // Clean up.
grpc_lb_addresses_destroy(lb_addresses);
- return result;
+ return new_args;
}
//
@@ -1292,8 +1302,9 @@
if (lb_channel_ == nullptr) {
char* uri_str;
gpr_asprintf(&uri_str, "fake:///%s", server_name_);
- lb_channel_ = grpc_lb_policy_grpclb_create_lb_channel(
- uri_str, client_channel_factory(), lb_channel_args);
+ lb_channel_ = grpc_client_channel_factory_create_channel(
+ client_channel_factory(), uri_str,
+ GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, lb_channel_args);
GPR_ASSERT(lb_channel_ != nullptr);
gpr_free(uri_str);
}
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.cc
index 013fb12..ebbe597 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.cc
@@ -16,57 +16,9 @@
*
*/
-#include <grpc/support/alloc.h>
-#include <grpc/support/string_util.h>
-
-#include "src/core/ext/filters/client_channel/client_channel.h"
#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
-#include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/gpr/string.h"
-#include "src/core/lib/iomgr/sockaddr_utils.h"
-grpc_channel* grpc_lb_policy_grpclb_create_lb_channel(
- const char* lb_service_target_addresses,
- grpc_client_channel_factory* client_channel_factory,
+grpc_channel_args* grpc_lb_policy_grpclb_modify_lb_channel_args(
grpc_channel_args* args) {
- grpc_channel* lb_channel = grpc_client_channel_factory_create_channel(
- client_channel_factory, lb_service_target_addresses,
- GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, args);
- return lb_channel;
-}
-
-grpc_channel_args* grpc_lb_policy_grpclb_build_lb_channel_args(
- grpc_slice_hash_table* targets_info,
- grpc_core::FakeResolverResponseGenerator* response_generator,
- const grpc_channel_args* args) {
- const grpc_arg to_add[] = {
- grpc_core::FakeResolverResponseGenerator::MakeChannelArg(
- response_generator)};
- /* We remove:
- *
- * - The channel arg for the LB policy name, since we want to use the default
- * (pick_first) in this case.
- *
- * - The channel arg for the resolved addresses, since that will be generated
- * by the name resolver used in the LB channel. Note that the LB channel
- * will use the fake resolver, so this won't actually generate a query
- * to DNS (or some other name service). However, the addresses returned by
- * the fake resolver will have is_balancer=false, whereas our own
- * addresses have is_balancer=true. We need the LB channel to return
- * addresses with is_balancer=false so that it does not wind up recursively
- * using the grpclb LB policy, as per the special case logic in
- * client_channel.c.
- *
- * - The channel arg for the server URI, since that will be different for the
- * LB channel than for the parent channel (the client channel factory will
- * re-add this arg with the right value).
- *
- * - The fake resolver generator, because we are replacing it with the one
- * from the grpclb policy, used to propagate updates to the LB channel. */
- static const char* keys_to_remove[] = {
- GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI,
- GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR};
- return grpc_channel_args_copy_and_add_and_remove(
- args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), to_add,
- GPR_ARRAY_SIZE(to_add));
+ return args;
}
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
index 2e34e3c..6635010 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
@@ -20,25 +20,15 @@
#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
-#include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
-#include "src/core/lib/slice/slice_hash_table.h"
-/** Create the channel used for communicating with an LB service.
- * Note that an LB *service* may be comprised of several LB *servers*.
- *
- * \a lb_service_target_addresses is the target URI containing the addresses
- * from resolving the LB service's name (eg, ipv4:10.0.0.1:1234,10.2.3.4:9876).
- * \a client_channel_factory will be used for the creation of the LB channel,
- * alongside the channel args passed in \a args. */
-grpc_channel* grpc_lb_policy_grpclb_create_lb_channel(
- const char* lb_service_target_addresses,
- grpc_client_channel_factory* client_channel_factory,
+/// Makes any necessary modifications to \a args for use in the grpclb
+/// balancer channel.
+///
+/// Takes ownership of \a args.
+///
+/// Caller takes ownership of the returned args.
+grpc_channel_args* grpc_lb_policy_grpclb_modify_lb_channel_args(
grpc_channel_args* args);
-grpc_channel_args* grpc_lb_policy_grpclb_build_lb_channel_args(
- grpc_slice_hash_table* targets_info,
- grpc_core::FakeResolverResponseGenerator* response_generator,
- const grpc_channel_args* args);
-
#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H \
*/
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.cc
index 5e615ad..254a5df 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.cc
@@ -16,11 +16,14 @@
*
*/
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
+
+#include <string.h>
+
#include <grpc/support/alloc.h>
#include <grpc/support/string_util.h>
#include "src/core/ext/filters/client_channel/client_channel.h"
-#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/gpr/string.h"
#include "src/core/lib/iomgr/sockaddr_utils.h"
@@ -28,73 +31,81 @@
#include "src/core/lib/security/transport/lb_targets_info.h"
#include "src/core/lib/slice/slice_internal.h"
-grpc_channel* grpc_lb_policy_grpclb_create_lb_channel(
- const char* lb_service_target_addresses,
- grpc_client_channel_factory* client_channel_factory,
+static void destroy_balancer_name(void* balancer_name) {
+ gpr_free(balancer_name);
+}
+
+static grpc_slice_hash_table_entry targets_info_entry_create(
+ const char* address, const char* balancer_name) {
+ grpc_slice_hash_table_entry entry;
+ entry.key = grpc_slice_from_copied_string(address);
+ entry.value = gpr_strdup(balancer_name);
+ return entry;
+}
+
+static int balancer_name_cmp_fn(void* a, void* b) {
+ const char* a_str = static_cast<const char*>(a);
+ const char* b_str = static_cast<const char*>(b);
+ return strcmp(a_str, b_str);
+}
+
+static grpc_slice_hash_table* build_targets_info_table(
+ grpc_lb_addresses* addresses) {
+ grpc_slice_hash_table_entry* targets_info_entries =
+ static_cast<grpc_slice_hash_table_entry*>(
+ gpr_zalloc(sizeof(*targets_info_entries) * addresses->num_addresses));
+ for (size_t i = 0; i < addresses->num_addresses; ++i) {
+ char* addr_str;
+ GPR_ASSERT(grpc_sockaddr_to_string(
+ &addr_str, &addresses->addresses[i].address, true) > 0);
+ targets_info_entries[i] = targets_info_entry_create(
+ addr_str, addresses->addresses[i].balancer_name);
+ gpr_free(addr_str);
+ }
+ grpc_slice_hash_table* targets_info = grpc_slice_hash_table_create(
+ addresses->num_addresses, targets_info_entries, destroy_balancer_name,
+ balancer_name_cmp_fn);
+ gpr_free(targets_info_entries);
+ return targets_info;
+}
+
+grpc_channel_args* grpc_lb_policy_grpclb_modify_lb_channel_args(
grpc_channel_args* args) {
- grpc_channel_args* new_args = args;
+ const char* args_to_remove[1];
+ size_t num_args_to_remove = 0;
+ grpc_arg args_to_add[2];
+ size_t num_args_to_add = 0;
+ // Add arg for targets info table.
+ const grpc_arg* arg = grpc_channel_args_find(args, GRPC_ARG_LB_ADDRESSES);
+ GPR_ASSERT(arg != nullptr);
+ GPR_ASSERT(arg->type == GRPC_ARG_POINTER);
+ grpc_lb_addresses* addresses =
+ static_cast<grpc_lb_addresses*>(arg->value.pointer.p);
+ grpc_slice_hash_table* targets_info = build_targets_info_table(addresses);
+ args_to_add[num_args_to_add++] =
+ grpc_lb_targets_info_create_channel_arg(targets_info);
+ // Substitute the channel credentials with a version without call
+ // credentials: the load balancer is not necessarily trusted to handle
+ // bearer token credentials.
grpc_channel_credentials* channel_credentials =
grpc_channel_credentials_find_in_args(args);
+ grpc_channel_credentials* creds_sans_call_creds = nullptr;
if (channel_credentials != nullptr) {
- /* Substitute the channel credentials with a version without call
- * credentials: the load balancer is not necessarily trusted to handle
- * bearer token credentials */
- static const char* keys_to_remove[] = {GRPC_ARG_CHANNEL_CREDENTIALS};
- grpc_channel_credentials* creds_sans_call_creds =
+ creds_sans_call_creds =
grpc_channel_credentials_duplicate_without_call_credentials(
channel_credentials);
GPR_ASSERT(creds_sans_call_creds != nullptr);
- grpc_arg args_to_add[] = {
- grpc_channel_credentials_to_arg(creds_sans_call_creds)};
- /* Create the new set of channel args */
- new_args = grpc_channel_args_copy_and_add_and_remove(
- args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), args_to_add,
- GPR_ARRAY_SIZE(args_to_add));
+ args_to_remove[num_args_to_remove++] = GRPC_ARG_CHANNEL_CREDENTIALS;
+ args_to_add[num_args_to_add++] =
+ grpc_channel_credentials_to_arg(creds_sans_call_creds);
+ }
+ grpc_channel_args* result = grpc_channel_args_copy_and_add_and_remove(
+ args, args_to_remove, num_args_to_remove, args_to_add, num_args_to_add);
+ // Clean up.
+ grpc_channel_args_destroy(args);
+ grpc_slice_hash_table_unref(targets_info);
+ if (creds_sans_call_creds != nullptr) {
grpc_channel_credentials_unref(creds_sans_call_creds);
}
- grpc_channel* lb_channel = grpc_client_channel_factory_create_channel(
- client_channel_factory, lb_service_target_addresses,
- GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, new_args);
- if (channel_credentials != nullptr) {
- grpc_channel_args_destroy(new_args);
- }
- return lb_channel;
-}
-
-grpc_channel_args* grpc_lb_policy_grpclb_build_lb_channel_args(
- grpc_slice_hash_table* targets_info,
- grpc_core::FakeResolverResponseGenerator* response_generator,
- const grpc_channel_args* args) {
- const grpc_arg to_add[] = {
- grpc_lb_targets_info_create_channel_arg(targets_info),
- grpc_core::FakeResolverResponseGenerator::MakeChannelArg(
- response_generator)};
- /* We remove:
- *
- * - The channel arg for the LB policy name, since we want to use the default
- * (pick_first) in this case.
- *
- * - The channel arg for the resolved addresses, since that will be generated
- * by the name resolver used in the LB channel. Note that the LB channel
- * will use the fake resolver, so this won't actually generate a query
- * to DNS (or some other name service). However, the addresses returned by
- * the fake resolver will have is_balancer=false, whereas our own
- * addresses have is_balancer=true. We need the LB channel to return
- * addresses with is_balancer=false so that it does not wind up recursively
- * using the grpclb LB policy, as per the special case logic in
- * client_channel.c.
- *
- * - The channel arg for the server URI, since that will be different for the
- * LB channel than for the parent channel (the client channel factory will
- * re-add this arg with the right value).
- *
- * - The fake resolver generator, because we are replacing it with the one
- * from the grpclb policy, used to propagate updates to the LB channel. */
- static const char* keys_to_remove[] = {
- GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI,
- GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR};
- /* Add the targets info table to be used for secure naming */
- return grpc_channel_args_copy_and_add_and_remove(
- args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), to_add,
- GPR_ARRAY_SIZE(to_add));
+ return result;
}
diff --git a/test/cpp/end2end/grpclb_end2end_test.cc b/test/cpp/end2end/grpclb_end2end_test.cc
index 96bd936..25e108e 100644
--- a/test/cpp/end2end/grpclb_end2end_test.cc
+++ b/test/cpp/end2end/grpclb_end2end_test.cc
@@ -58,6 +58,8 @@
// - Test handling of creation of faulty RR instance by having the LB return a
// serverlist with non-existent backends after having initially returned a
// valid one.
+// - test using secure credentials and make sure we don't send call
+// credentials to the balancer
//
// Findings from end to end testing to be covered here:
// - Handling of LB servers restart, including reconnection after backing-off