diff --git a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_connector.erl b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_client.erl
similarity index 88%
rename from apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_connector.erl
rename to apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_client.erl
index 35a4a7797..f2fa87d38 100644
--- a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_connector.erl
+++ b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_client.erl
@@ -2,9 +2,7 @@
 %% Copyright (c) 2022-2023 EMQ Technologies Co., Ltd. All Rights Reserved.
 %%--------------------------------------------------------------------
 
--module(emqx_bridge_gcp_pubsub_connector).
-
--behaviour(emqx_resource).
+-module(emqx_bridge_gcp_pubsub_client).
 
 -include_lib("jose/include/jose_jwk.hrl").
 -include_lib("emqx_connector/include/emqx_connector_tables.hrl").
@@ -13,18 +11,17 @@
 -include_lib("emqx/include/logger.hrl").
 -include_lib("snabbkaffe/include/snabbkaffe.hrl").
 
-%% `emqx_resource' API
+%% API
 -export([
-    callback_mode/0,
-    on_start/2,
-    on_stop/2,
-    on_query/3,
-    on_query_async/4,
-    on_get_status/2
+    start/2,
+    stop/1,
+    query_sync/2,
+    query_async/3,
+    get_status/1
 ]).
 -export([reply_delegator/3]).
 
--export([get_topic/3]).
+-export([get_topic/2]).
 
 -export([get_jwt_authorization_header/1]).
 
@@ -37,7 +34,7 @@
     service_account_json := service_account_json(),
     any() => term()
 }.
--type state() :: #{
+-opaque state() :: #{
     connect_timeout := timer:time(),
     jwt_config := emqx_connector_jwt:jwt_config(),
     max_retries := non_neg_integer(),
@@ -66,13 +63,11 @@
 -define(DEFAULT_PIPELINE_SIZE, 100).
 
 %%-------------------------------------------------------------------------------------------------
-%% emqx_resource API
+%% API
 %%-------------------------------------------------------------------------------------------------
 
-callback_mode() -> async_if_possible.
-
--spec on_start(resource_id(), config()) -> {ok, state()} | {error, term()}.
-on_start(
+-spec start(resource_id(), config()) -> {ok, state()} | {error, term()}.
+start(
     ResourceId,
     #{
         connect_timeout := ConnectTimeout,
@@ -81,11 +76,6 @@ on_start(
         resource_opts := #{request_ttl := RequestTTL}
     } = Config
 ) ->
-    ?SLOG(info, #{
-        msg => "starting_gcp_pubsub_bridge",
-        connector => ResourceId,
-        config => Config
-    }),
     {Transport, HostPort} = get_transport(),
     #{hostname := Host, port := Port} = emqx_schema:parse_server(HostPort, #{default_port => 443}),
     PoolType = random,
@@ -141,8 +131,8 @@ on_start(
             {error, Reason}
     end.
 
--spec on_stop(resource_id(), state() | undefined) -> ok | {error, term()}.
-on_stop(ResourceId, _State) ->
+-spec stop(resource_id()) -> ok | {error, term()}.
+stop(ResourceId) ->
     ?tp(gcp_pubsub_stop, #{resource_id => ResourceId}),
     ?SLOG(info, #{
         msg => "stopping_gcp_pubsub_bridge",
@@ -158,42 +148,41 @@ on_stop(ResourceId, _State) ->
             Error
     end.
 
--spec on_query(
-    resource_id(),
+-spec query_sync(
     {prepared_request, prepared_request()},
     state()
 ) ->
     {ok, map()} | {error, {recoverable_error, term()} | term()}.
-on_query(ResourceId, {prepared_request, PreparedRequest = {_Method, _Path, _Body}}, State) ->
+query_sync({prepared_request, PreparedRequest = {_Method, _Path, _Body}}, State) ->
+    PoolName = maps:get(pool_name, State),
     ?TRACE(
         "QUERY_SYNC",
         "gcp_pubsub_received",
-        #{requests => PreparedRequest, connector => ResourceId, state => State}
+        #{requests => PreparedRequest, connector => PoolName, state => State}
     ),
-    do_send_requests_sync(State, {prepared_request, PreparedRequest}, ResourceId).
+    do_send_requests_sync(State, {prepared_request, PreparedRequest}).
 
--spec on_query_async(
-    resource_id(),
+-spec query_async(
     {prepared_request, prepared_request()},
     {ReplyFun :: function(), Args :: list()},
     state()
 ) -> {ok, pid()}.
-on_query_async(
-    ResourceId,
+query_async(
     {prepared_request, PreparedRequest = {_Method, _Path, _Body}},
     ReplyFunAndArgs,
     State
 ) ->
+    PoolName = maps:get(pool_name, State),
     ?TRACE(
         "QUERY_ASYNC",
         "gcp_pubsub_received",
-        #{requests => PreparedRequest, connector => ResourceId, state => State}
+        #{requests => PreparedRequest, connector => PoolName, state => State}
     ),
-    do_send_requests_async(State, {prepared_request, PreparedRequest}, ReplyFunAndArgs, ResourceId).
+    do_send_requests_async(State, {prepared_request, PreparedRequest}, ReplyFunAndArgs).
 
--spec on_get_status(resource_id(), state()) -> connected | disconnected.
-on_get_status(ResourceId, #{connect_timeout := Timeout} = State) ->
-    case do_get_status(ResourceId, Timeout) of
+-spec get_status(state()) -> connected | disconnected.
+get_status(#{connect_timeout := Timeout, pool_name := PoolName} = State) ->
+    case do_get_status(PoolName, Timeout) of
         true ->
             connected;
         false ->
@@ -208,14 +197,14 @@ on_get_status(ResourceId, #{connect_timeout := Timeout} = State) ->
 %% API
 %%-------------------------------------------------------------------------------------------------
 
--spec get_topic(resource_id(), topic(), state()) -> {ok, map()} | {error, term()}.
-get_topic(ResourceId, Topic, ConnectorState) ->
+-spec get_topic(topic(), state()) -> {ok, map()} | {error, term()}.
+get_topic(Topic, ConnectorState) ->
     #{project_id := ProjectId} = ConnectorState,
     Method = get,
     Path = <<"/v1/projects/", ProjectId/binary, "/topics/", Topic/binary>>,
     Body = <<>>,
     PreparedRequest = {prepared_request, {Method, Path, Body}},
-    on_query(ResourceId, PreparedRequest, ConnectorState).
+    query_sync(PreparedRequest, ConnectorState).
 
 %%-------------------------------------------------------------------------------------------------
 %% Helper fns
@@ -286,11 +275,10 @@ get_jwt_authorization_header(JWTConfig) ->
 
 -spec do_send_requests_sync(
     state(),
-    {prepared_request, prepared_request()},
-    resource_id()
+    {prepared_request, prepared_request()}
 ) ->
     {ok, map()} | {error, {recoverable_error, term()} | term()}.
-do_send_requests_sync(State, {prepared_request, {Method, Path, Body}}, ResourceId) ->
+do_send_requests_sync(State, {prepared_request, {Method, Path, Body}}) ->
     #{
         pool_name := PoolName,
         max_retries := MaxRetries,
@@ -301,7 +289,7 @@ do_send_requests_sync(State, {prepared_request, {Method, Path, Body}}, ResourceI
         #{
             request => {prepared_request, {Method, Path, Body}},
             query_mode => sync,
-            resource_id => ResourceId
+            resource_id => PoolName
         }
     ),
     Request = to_ehttpc_request(State, Method, Path, Body),
@@ -312,16 +300,15 @@ do_send_requests_sync(State, {prepared_request, {Method, Path, Body}}, ResourceI
         RequestTTL,
         MaxRetries
     ),
-    handle_response(Response, ResourceId, _QueryMode = sync).
+    handle_response(Response, PoolName, _QueryMode = sync).
 
 -spec do_send_requests_async(
     state(),
     {prepared_request, prepared_request()},
-    {ReplyFun :: function(), Args :: list()},
-    resource_id()
+    {ReplyFun :: function(), Args :: list()}
 ) -> {ok, pid()}.
 do_send_requests_async(
-    State, {prepared_request, {Method, Path, Body}}, ReplyFunAndArgs, ResourceId
+    State, {prepared_request, {Method, Path, Body}}, ReplyFunAndArgs
 ) ->
     #{
         pool_name := PoolName,
@@ -332,7 +319,7 @@ do_send_requests_async(
         #{
             request => {prepared_request, {Method, Path, Body}},
             query_mode => async,
-            resource_id => ResourceId
+            resource_id => PoolName
         }
     ),
     Request = to_ehttpc_request(State, Method, Path, Body),
@@ -342,7 +329,7 @@ do_send_requests_async(
         Method,
         Request,
         RequestTTL,
-        {fun ?MODULE:reply_delegator/3, [ResourceId, ReplyFunAndArgs]}
+        {fun ?MODULE:reply_delegator/3, [PoolName, ReplyFunAndArgs]}
     ),
     {ok, Worker}.
 
diff --git a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_consumer_worker.erl b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_consumer_worker.erl
index 7684d1469..bb9e75a9c 100644
--- a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_consumer_worker.erl
+++ b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_consumer_worker.erl
@@ -31,29 +31,31 @@
 -type ack_id() :: binary().
 -type config() :: #{
     ack_retry_interval := emqx_schema:timeout_duration_ms(),
-    connector_state := emqx_bridge_gcp_pubsub_connector:state(),
+    client := emqx_bridge_gcp_pubsub_client:state(),
     ecpool_worker_id => non_neg_integer(),
     hookpoint := binary(),
     instance_id := binary(),
     mqtt_config => emqx_bridge_gcp_pubsub_impl_consumer:mqtt_config(),
+    project_id := emqx_bridge_gcp_pubsub_client:project_id(),
     pull_max_messages := non_neg_integer(),
     subscription_id => subscription_id(),
-    topic => emqx_bridge_gcp_pubsub_connector:topic()
+    topic => emqx_bridge_gcp_pubsub_client:topic()
 }.
 -type state() :: #{
     ack_retry_interval := emqx_schema:timeout_duration_ms(),
     ack_timer := undefined | reference(),
     async_workers := #{pid() => reference()},
-    connector_state := emqx_bridge_gcp_pubsub_connector:state(),
+    client := emqx_bridge_gcp_pubsub_client:state(),
     ecpool_worker_id := non_neg_integer(),
     hookpoint := binary(),
     instance_id := binary(),
     mqtt_config => emqx_bridge_gcp_pubsub_impl_consumer:mqtt_config(),
     pending_acks => [ack_id()],
+    project_id := emqx_bridge_gcp_pubsub_client:project_id(),
     pull_max_messages := non_neg_integer(),
     pull_timer := undefined | reference(),
     subscription_id => subscription_id(),
-    topic => emqx_bridge_gcp_pubsub_connector:topic()
+    topic => emqx_bridge_gcp_pubsub_client:topic()
 }.
 -type decoded_message() :: map().
 
@@ -129,10 +131,11 @@ connect(Opts0) ->
     #{
         ack_retry_interval := AckRetryInterval,
         bridge_name := BridgeName,
-        connector_state := ConnectorState,
+        client := Client,
         ecpool_worker_id := WorkerId,
         hookpoint := Hookpoint,
         instance_id := InstanceId,
+        project_id := ProjectId,
         pull_max_messages := PullMaxMessages,
         topic_mapping := TopicMapping
     } = Opts,
@@ -141,13 +144,14 @@ connect(Opts0) ->
     {Topic, MQTTConfig} = lists:nth(Index, TopicMappingList),
     Config = #{
         ack_retry_interval => AckRetryInterval,
-        %% Note: the `connector_state' value here must be immutable and not changed by the
+        %% Note: the `client' value here must be immutable and not changed by the
         %% bridge during `on_get_status', since we have handed it over to the pull
         %% workers.
-        connector_state => ConnectorState,
+        client => Client,
         hookpoint => Hookpoint,
         instance_id => InstanceId,
         mqtt_config => MQTTConfig,
+        project_id => ProjectId,
         pull_max_messages => PullMaxMessages,
         topic => Topic,
         subscription_id => subscription_id(BridgeName, Topic)
@@ -264,7 +268,7 @@ ensure_pull_timer(State) ->
 -spec ensure_subscription_exists(state()) -> ok | error.
 ensure_subscription_exists(State) ->
     #{
-        connector_state := ConnectorState,
+        client := Client,
         instance_id := InstanceId,
         subscription_id := SubscriptionId,
         topic := Topic
@@ -273,7 +277,7 @@ ensure_subscription_exists(State) ->
     Path = path(State, create),
     Body = body(State, create),
     PreparedRequest = {prepared_request, {Method, Path, Body}},
-    Res = emqx_bridge_gcp_pubsub_connector:on_query(InstanceId, PreparedRequest, ConnectorState),
+    Res = emqx_bridge_gcp_pubsub_client:query_sync(PreparedRequest, Client),
     case Res of
         {error, #{status_code := 409}} ->
             %% already exists
@@ -287,9 +291,7 @@ ensure_subscription_exists(State) ->
             Path1 = path(State, create),
             Body1 = body(State, patch_subscription),
             PreparedRequest1 = {prepared_request, {Method1, Path1, Body1}},
-            Res1 = emqx_bridge_gcp_pubsub_connector:on_query(
-                InstanceId, PreparedRequest1, ConnectorState
-            ),
+            Res1 = emqx_bridge_gcp_pubsub_client:query_sync(PreparedRequest1, Client),
             ?SLOG(debug, #{
                 msg => "gcp_pubsub_consumer_worker_subscription_patch",
                 instance_id => InstanceId,
@@ -319,7 +321,7 @@ ensure_subscription_exists(State) ->
 %% We use async requests so that this process will be more responsive to system messages.
 do_pull_async(State) ->
     #{
-        connector_state := ConnectorState,
+        client := Client,
         instance_id := InstanceId
     } = State,
     Method = post,
@@ -327,11 +329,10 @@ do_pull_async(State) ->
     Body = body(State, pull),
     PreparedRequest = {prepared_request, {Method, Path, Body}},
     ReplyFunAndArgs = {fun ?MODULE:reply_delegator/3, [self(), InstanceId]},
-    {ok, AsyncWorkerPid} = emqx_bridge_gcp_pubsub_connector:on_query_async(
-        InstanceId,
+    {ok, AsyncWorkerPid} = emqx_bridge_gcp_pubsub_client:query_async(
         PreparedRequest,
         ReplyFunAndArgs,
-        ConnectorState
+        Client
     ),
     ensure_async_worker_monitored(State, AsyncWorkerPid).
 
@@ -361,15 +362,14 @@ acknowledge(State0 = #{pending_acks := []}) ->
 acknowledge(State0) ->
     State1 = State0#{ack_timer := undefined},
     #{
-        connector_state := ConnectorState,
-        instance_id := InstanceId,
+        client := Client,
         pending_acks := AckIds
     } = State1,
     Method = post,
     Path = path(State1, ack),
     Body = body(State1, ack, #{ack_ids => AckIds}),
     PreparedRequest = {prepared_request, {Method, Path, Body}},
-    Res = emqx_bridge_gcp_pubsub_connector:on_query(InstanceId, PreparedRequest, ConnectorState),
+    Res = emqx_bridge_gcp_pubsub_client:query_sync(PreparedRequest, Client),
     case Res of
         {error, Reason} ->
             ?SLOG(warning, #{msg => "gcp_pubsub_consumer_worker_ack_error", reason => Reason}),
@@ -384,14 +384,13 @@ acknowledge(State0) ->
 
 do_get_subscription(State) ->
     #{
-        connector_state := ConnectorState,
-        instance_id := InstanceId
+        client := Client
     } = State,
     Method = get,
     Path = path(State, get_subscription),
     Body = body(State, get_subscription),
     PreparedRequest = {prepared_request, {Method, Path, Body}},
-    Res = emqx_bridge_gcp_pubsub_connector:on_query(InstanceId, PreparedRequest, ConnectorState),
+    Res = emqx_bridge_gcp_pubsub_client:query_sync(PreparedRequest, Client),
     case Res of
         {error, Reason} ->
             ?SLOG(warning, #{
@@ -410,7 +409,7 @@ do_get_subscription(State) ->
             {error, Details}
     end.
 
--spec subscription_id(bridge_name(), emqx_bridge_gcp_pubsub_connector:topic()) -> subscription_id().
+-spec subscription_id(bridge_name(), emqx_bridge_gcp_pubsub_client:topic()) -> subscription_id().
 subscription_id(BridgeName0, Topic) ->
     %% The real GCP PubSub accepts colons in subscription names, but its emulator
     %% doesn't...  We currently validate bridge names to not include that character.  The
@@ -422,7 +421,7 @@ subscription_id(BridgeName0, Topic) ->
 -spec path(state(), pull | create | ack | get_subscription) -> binary().
 path(State, Type) ->
     #{
-        connector_state := #{project_id := ProjectId},
+        client := #{project_id := ProjectId},
         subscription_id := SubscriptionId
     } = State,
     SubscriptionResource = subscription_resource(ProjectId, SubscriptionId),
@@ -444,7 +443,7 @@ body(State, pull) ->
 body(State, create) ->
     #{
         ack_retry_interval := AckRetryInterval,
-        connector_state := #{project_id := ProjectId},
+        project_id := ProjectId,
         topic := PubSubTopic
     } = State,
     TopicResource = <<"projects/", ProjectId/binary, "/topics/", PubSubTopic/binary>>,
@@ -457,7 +456,7 @@ body(State, create) ->
 body(State, patch_subscription) ->
     #{
         ack_retry_interval := AckRetryInterval,
-        connector_state := #{project_id := ProjectId},
+        project_id := ProjectId,
         topic := PubSubTopic,
         subscription_id := SubscriptionId
     } = State,
@@ -484,7 +483,7 @@ body(_State, ack, Opts) ->
     JSON = #{<<"ackIds">> => AckIds},
     emqx_utils_json:encode(JSON).
 
--spec subscription_resource(emqx_bridge_gcp_pubsub_connector:project_id(), subscription_id()) ->
+-spec subscription_resource(emqx_bridge_gcp_pubsub_client:project_id(), subscription_id()) ->
     binary().
 subscription_resource(ProjectId, SubscriptionId) ->
     <<"projects/", ProjectId/binary, "/subscriptions/", SubscriptionId/binary>>.
diff --git a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_consumer.erl b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_consumer.erl
index e004875f9..88b57be1e 100644
--- a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_consumer.erl
+++ b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_consumer.erl
@@ -29,11 +29,11 @@
     max_retries := non_neg_integer(),
     pool_size := non_neg_integer(),
     resource_opts := #{request_ttl := infinity | emqx_schema:duration_ms(), any() => term()},
-    service_account_json := emqx_bridge_gcp_pubsub_connector:service_account_json(),
+    service_account_json := emqx_bridge_gcp_pubsub_client:service_account_json(),
     any() => term()
 }.
 -type state() :: #{
-    connector_state := emqx_bridge_gcp_pubsub_connector:state()
+    client := emqx_bridge_gcp_pubsub_client:state()
 }.
 
 -export_type([mqtt_config/0]).
@@ -52,24 +52,21 @@ query_mode(_Config) -> no_queries.
 
 -spec on_start(resource_id(), config()) -> {ok, state()} | {error, term()}.
 on_start(InstanceId, Config) ->
-    case emqx_bridge_gcp_pubsub_connector:on_start(InstanceId, Config) of
-        {ok, ConnectorState} ->
-            start_consumers(InstanceId, ConnectorState, Config);
+    case emqx_bridge_gcp_pubsub_client:start(InstanceId, Config) of
+        {ok, Client} ->
+            start_consumers(InstanceId, Client, Config);
         Error ->
             Error
     end.
 
 -spec on_stop(resource_id(), state()) -> ok | {error, term()}.
-on_stop(InstanceId, #{connector_state := ConnectorState}) ->
+on_stop(InstanceId, _State) ->
     ok = stop_consumers(InstanceId),
-    emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, ConnectorState);
-on_stop(InstanceId, undefined = _State) ->
-    ok = stop_consumers(InstanceId),
-    emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, undefined).
+    emqx_bridge_gcp_pubsub_client:stop(InstanceId).
 
 -spec on_get_status(resource_id(), state()) -> connected | disconnected.
 on_get_status(InstanceId, _State) ->
-    %% Note: do *not* alter the `connector_state' value here.  It must be immutable, since
+    %% Note: do *not* alter the `client' value here.  It must be immutable, since
     %% we have handed it over to the pull workers.
     case
         emqx_resource_pool:health_check_workers(
@@ -85,11 +82,12 @@ on_get_status(InstanceId, _State) ->
 %% Internal fns
 %%-------------------------------------------------------------------------------------------------
 
-start_consumers(InstanceId, ConnectorState, Config) ->
+start_consumers(InstanceId, Client, Config) ->
     #{
         bridge_name := BridgeName,
         consumer := ConsumerConfig0,
-        hookpoint := Hookpoint
+        hookpoint := Hookpoint,
+        service_account_json := #{project_id := ProjectId}
     } = Config,
     ConsumerConfig1 = maps:update_with(topic_mapping, fun convert_topic_mapping/1, ConsumerConfig0),
     TopicMapping = maps:get(topic_mapping, ConsumerConfig1),
@@ -98,18 +96,19 @@ start_consumers(InstanceId, ConnectorState, Config) ->
     ConsumerConfig = ConsumerConfig1#{
         auto_reconnect => ?AUTO_RECONNECT_S,
         bridge_name => BridgeName,
-        connector_state => ConnectorState,
+        client => Client,
         hookpoint => Hookpoint,
         instance_id => InstanceId,
-        pool_size => PoolSize
+        pool_size => PoolSize,
+        project_id => ProjectId
     },
     ConsumerOpts = maps:to_list(ConsumerConfig),
     %% FIXME: mark as unhealthy if topics do not exist!
-    case validate_pubsub_topics(InstanceId, TopicMapping, ConnectorState) of
+    case validate_pubsub_topics(TopicMapping, Client) of
         ok ->
             ok;
         error ->
-            _ = emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, ConnectorState),
+            _ = emqx_bridge_gcp_pubsub_client:stop(InstanceId),
             throw(
                 "GCP PubSub topics are invalid.  Please check the logs, check if the "
                 "topic exists in GCP and if the service account has permissions to use them."
@@ -120,12 +119,12 @@ start_consumers(InstanceId, ConnectorState, Config) ->
     of
         ok ->
             State = #{
-                connector_state => ConnectorState,
+                client => Client,
                 pool_name => InstanceId
             },
             {ok, State};
         {error, Reason} ->
-            _ = emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, ConnectorState),
+            _ = emqx_bridge_gcp_pubsub_client:stop(InstanceId),
             {error, Reason}
     end.
 
@@ -163,23 +162,23 @@ convert_topic_mapping(TopicMappingList) ->
         TopicMappingList
     ).
 
-validate_pubsub_topics(InstanceId, TopicMapping, ConnectorState) ->
+validate_pubsub_topics(TopicMapping, Client) ->
     PubSubTopics = maps:keys(TopicMapping),
-    do_validate_pubsub_topics(InstanceId, ConnectorState, PubSubTopics).
+    do_validate_pubsub_topics(Client, PubSubTopics).
 
-do_validate_pubsub_topics(InstanceId, ConnectorState, [Topic | Rest]) ->
-    case check_for_topic_existence(InstanceId, Topic, ConnectorState) of
+do_validate_pubsub_topics(Client, [Topic | Rest]) ->
+    case check_for_topic_existence(Topic, Client) of
         ok ->
-            do_validate_pubsub_topics(InstanceId, ConnectorState, Rest);
+            do_validate_pubsub_topics(Client, Rest);
         {error, _} ->
             error
     end;
-do_validate_pubsub_topics(_InstanceId, _ConnectorState, []) ->
+do_validate_pubsub_topics(_Client, []) ->
     %% we already validate that the mapping is not empty in the config schema.
     ok.
 
-check_for_topic_existence(InstanceId, Topic, ConnectorState) ->
-    Res = emqx_bridge_gcp_pubsub_connector:get_topic(InstanceId, Topic, ConnectorState),
+check_for_topic_existence(Topic, Client) ->
+    Res = emqx_bridge_gcp_pubsub_client:get_topic(Topic, Client),
     case Res of
         {ok, _} ->
             ok;
diff --git a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_producer.erl b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_producer.erl
index 1f198af23..d2469160b 100644
--- a/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_producer.erl
+++ b/apps/emqx_bridge_gcp_pubsub/src/emqx_bridge_gcp_pubsub_impl_producer.erl
@@ -13,17 +13,18 @@
     max_retries := non_neg_integer(),
     pubsub_topic := binary(),
     resource_opts := #{request_ttl := infinity | emqx_schema:duration_ms(), any() => term()},
-    service_account_json := emqx_bridge_gcp_pubsub_connector:service_account_json(),
+    service_account_json := emqx_bridge_gcp_pubsub_client:service_account_json(),
     any() => term()
 }.
 -type state() :: #{
-    connector_state := emqx_bridge_gcp_pubsub_connector:state(),
+    client := emqx_bridge_gcp_pubsub_client:state(),
     payload_template := emqx_placeholder:tmpl_token(),
+    project_id := emqx_bridge_gcp_pubsub_client:project_id(),
     pubsub_topic := binary()
 }.
--type headers() :: emqx_bridge_gcp_pubsub_connector:headers().
--type body() :: emqx_bridge_gcp_pubsub_connector:body().
--type status_code() :: emqx_bridge_gcp_pubsub_connector:status_code().
+-type headers() :: emqx_bridge_gcp_pubsub_client:headers().
+-type body() :: emqx_bridge_gcp_pubsub_client:body().
+-type status_code() :: emqx_bridge_gcp_pubsub_client:status_code().
 
 %% `emqx_resource' API
 -export([
@@ -50,15 +51,21 @@ query_mode(_Config) -> async.
 
 -spec on_start(resource_id(), config()) -> {ok, state()} | {error, term()}.
 on_start(InstanceId, Config) ->
+    ?SLOG(info, #{
+        msg => "starting_gcp_pubsub_bridge",
+        config => Config
+    }),
     #{
         payload_template := PayloadTemplate,
-        pubsub_topic := PubSubTopic
+        pubsub_topic := PubSubTopic,
+        service_account_json := #{project_id := ProjectId}
     } = Config,
-    case emqx_bridge_gcp_pubsub_connector:on_start(InstanceId, Config) of
-        {ok, ConnectorState} ->
+    case emqx_bridge_gcp_pubsub_client:start(InstanceId, Config) of
+        {ok, Client} ->
             State = #{
-                connector_state => ConnectorState,
+                client => Client,
                 payload_template => emqx_placeholder:preproc_tmpl(PayloadTemplate),
+                project_id => ProjectId,
                 pubsub_topic => PubSubTopic
             },
             {ok, State};
@@ -67,22 +74,19 @@ on_start(InstanceId, Config) ->
     end.
 
 -spec on_stop(resource_id(), state()) -> ok | {error, term()}.
-on_stop(InstanceId, #{connector_state := ConnectorState}) ->
-    emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, ConnectorState);
-on_stop(InstanceId, undefined = _State) ->
-    emqx_bridge_gcp_pubsub_connector:on_stop(InstanceId, undefined).
+on_stop(InstanceId, _State) ->
+    emqx_bridge_gcp_pubsub_client:stop(InstanceId).
 
 -spec on_get_status(resource_id(), state()) -> connected | disconnected.
-on_get_status(InstanceId, #{connector_state := ConnectorState} = _State) ->
-    emqx_bridge_gcp_pubsub_connector:on_get_status(InstanceId, ConnectorState).
+on_get_status(_InstanceId, #{client := Client} = _State) ->
+    emqx_bridge_gcp_pubsub_client:get_status(Client).
 
 -spec on_query(
     resource_id(),
     {send_message, map()},
     state()
 ) ->
-    {ok, status_code(), headers()}
-    | {ok, status_code(), headers(), body()}
+    {ok, map()}
     | {error, {recoverable_error, term()}}
     | {error, term()}.
 on_query(ResourceId, {send_message, Selected}, State) ->
@@ -107,15 +111,14 @@ on_query_async(ResourceId, {send_message, Selected}, ReplyFunAndArgs, State) ->
         "gcp_pubsub_received",
         #{requests => Requests, connector => ResourceId, state => State}
     ),
-    do_send_requests_async(State, Requests, ReplyFunAndArgs, ResourceId).
+    do_send_requests_async(State, Requests, ReplyFunAndArgs).
 
 -spec on_batch_query(
     resource_id(),
     [{send_message, map()}],
     state()
 ) ->
-    {ok, status_code(), headers()}
-    | {ok, status_code(), headers(), body()}
+    {ok, map()}
     | {error, {recoverable_error, term()}}
     | {error, term()}.
 on_batch_query(ResourceId, Requests, State) ->
@@ -138,7 +141,7 @@ on_batch_query_async(ResourceId, Requests, ReplyFunAndArgs, State) ->
         "gcp_pubsub_received",
         #{requests => Requests, connector => ResourceId, state => State}
     ),
-    do_send_requests_async(State, Requests, ReplyFunAndArgs, ResourceId).
+    do_send_requests_async(State, Requests, ReplyFunAndArgs).
 
 %%-------------------------------------------------------------------------------------------------
 %% Helper fns
@@ -154,7 +157,7 @@ on_batch_query_async(ResourceId, Requests, ReplyFunAndArgs, State) ->
     | {error, {recoverable_error, term()}}
     | {error, term()}.
 do_send_requests_sync(State, Requests, InstanceId) ->
-    #{connector_state := ConnectorState} = State,
+    #{client := Client} = State,
     Payloads =
         lists:map(
             fun({send_message, Selected}) ->
@@ -166,18 +169,17 @@ do_send_requests_sync(State, Requests, InstanceId) ->
     Path = publish_path(State),
     Method = post,
     Request = {prepared_request, {Method, Path, Body}},
-    Result = emqx_bridge_gcp_pubsub_connector:on_query(InstanceId, Request, ConnectorState),
+    Result = emqx_bridge_gcp_pubsub_client:query_sync(Request, Client),
     QueryMode = sync,
     handle_result(Result, Request, QueryMode, InstanceId).
 
 -spec do_send_requests_async(
     state(),
     [{send_message, map()}],
-    {ReplyFun :: function(), Args :: list()},
-    resource_id()
+    {ReplyFun :: function(), Args :: list()}
 ) -> {ok, pid()}.
-do_send_requests_async(State, Requests, ReplyFunAndArgs0, InstanceId) ->
-    #{connector_state := ConnectorState} = State,
+do_send_requests_async(State, Requests, ReplyFunAndArgs0) ->
+    #{client := Client} = State,
     Payloads =
         lists:map(
             fun({send_message, Selected}) ->
@@ -190,8 +192,8 @@ do_send_requests_async(State, Requests, ReplyFunAndArgs0, InstanceId) ->
     Method = post,
     Request = {prepared_request, {Method, Path, Body}},
     ReplyFunAndArgs = {fun ?MODULE:reply_delegator/2, [ReplyFunAndArgs0]},
-    emqx_bridge_gcp_pubsub_connector:on_query_async(
-        InstanceId, Request, ReplyFunAndArgs, ConnectorState
+    emqx_bridge_gcp_pubsub_client:query_async(
+        Request, ReplyFunAndArgs, Client
     ).
 
 -spec encode_payload(state(), Selected :: map()) -> #{data := binary()}.
@@ -210,7 +212,7 @@ to_pubsub_request(Payloads) ->
 -spec publish_path(state()) -> binary().
 publish_path(
     _State = #{
-        connector_state := #{project_id := ProjectId},
+        project_id := ProjectId,
         pubsub_topic := PubSubTopic
     }
 ) ->
diff --git a/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_consumer_SUITE.erl b/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_consumer_SUITE.erl
index 6d81b88d2..2e32f630a 100644
--- a/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_consumer_SUITE.erl
+++ b/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_consumer_SUITE.erl
@@ -44,14 +44,14 @@ init_per_suite(Config) ->
             emqx_mgmt_api_test_util:init_suite(),
             HostPort = GCPEmulatorHost ++ ":" ++ GCPEmulatorPortStr,
             true = os:putenv("PUBSUB_EMULATOR_HOST", HostPort),
-            ConnectorState = start_control_connector(),
+            Client = start_control_connector(),
             [
                 {proxy_name, ProxyName},
                 {proxy_host, ProxyHost},
                 {proxy_port, ProxyPort},
                 {gcp_emulator_host, GCPEmulatorHost},
                 {gcp_emulator_port, GCPEmulatorPort},
-                {connector_state, ConnectorState}
+                {client, Client}
                 | Config
             ];
         false ->
@@ -64,8 +64,8 @@ init_per_suite(Config) ->
     end.
 
 end_per_suite(Config) ->
-    ConnectorState = ?config(connector_state, Config),
-    stop_control_connector(ConnectorState),
+    Client = ?config(client, Config),
+    stop_control_connector(Client),
     emqx_mgmt_api_test_util:end_suite(),
     ok = emqx_common_test_helpers:stop_apps([emqx_conf]),
     ok = emqx_connector_test_helpers:stop_apps([emqx_bridge, emqx_resource, emqx_rule_engine]),
@@ -229,14 +229,13 @@ ensure_topics(Config) ->
 
 ensure_topic(Config, Topic) ->
     ProjectId = ?config(project_id, Config),
-    ConnectorState = #{pool_name := PoolName} = ?config(connector_state, Config),
+    Client = ?config(client, Config),
     Method = put,
     Path = <<"/v1/projects/", ProjectId/binary, "/topics/", Topic/binary>>,
     Body = <<"{}">>,
-    Res = emqx_bridge_gcp_pubsub_connector:on_query(
-        PoolName,
+    Res = emqx_bridge_gcp_pubsub_client:query_sync(
         {prepared_request, {Method, Path, Body}},
-        ConnectorState
+        Client
     ),
     case Res of
         {ok, _} ->
@@ -259,16 +258,15 @@ start_control_connector() ->
             service_account_json => ServiceAccount
         },
     PoolName = <<"control_connector">>,
-    {ok, ConnectorState} = emqx_bridge_gcp_pubsub_connector:on_start(PoolName, ConnectorConfig),
-    ConnectorState.
+    {ok, Client} = emqx_bridge_gcp_pubsub_client:start(PoolName, ConnectorConfig),
+    Client.
 
-stop_control_connector(ConnectorState) ->
-    #{pool_name := PoolName} = ConnectorState,
-    ok = emqx_bridge_gcp_pubsub_connector:on_stop(PoolName, ConnectorState),
+stop_control_connector(Client) ->
+    ok = emqx_bridge_gcp_pubsub_client:stop(Client),
     ok.
 
 pubsub_publish(Config, Topic, Messages0) ->
-    ConnectorState = #{pool_name := PoolName} = ?config(connector_state, Config),
+    Client = ?config(client, Config),
     ProjectId = ?config(project_id, Config),
     Method = post,
     Path = <<"/v1/projects/", ProjectId/binary, "/topics/", Topic/binary, ":publish">>,
@@ -287,10 +285,9 @@ pubsub_publish(Config, Topic, Messages0) ->
             Messages0
         ),
     Body = emqx_utils_json:encode(#{<<"messages">> => Messages}),
-    {ok, _} = emqx_bridge_gcp_pubsub_connector:on_query(
-        PoolName,
+    {ok, _} = emqx_bridge_gcp_pubsub_client:query_sync(
         {prepared_request, {Method, Path, Body}},
-        ConnectorState
+        Client
     ),
     ok.
 
@@ -688,3 +685,4 @@ t_bridge_rule_action_source(Config) ->
 %%   * connection down during ack
 %%   * topic deleted while consumer is running
 %%   * subscription deleted while consumer is running
+%%   * ensure client is terminated when bridge stops
diff --git a/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_producer_SUITE.erl b/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_producer_SUITE.erl
index 5b1e7c6c6..67e4f52d1 100644
--- a/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_producer_SUITE.erl
+++ b/apps/emqx_bridge_gcp_pubsub/test/emqx_bridge_gcp_pubsub_producer_SUITE.erl
@@ -74,7 +74,7 @@ init_per_suite(Config) ->
     ok = emqx_connector_test_helpers:start_apps([emqx_resource, emqx_bridge, emqx_rule_engine]),
     {ok, _} = application:ensure_all_started(emqx_connector),
     emqx_mgmt_api_test_util:init_suite(),
-    persistent_term:put({emqx_bridge_gcp_pubsub_connector, transport}, tls),
+    persistent_term:put({emqx_bridge_gcp_pubsub_client, transport}, tls),
     Config.
 
 end_per_suite(_Config) ->
@@ -82,7 +82,7 @@ end_per_suite(_Config) ->
     ok = emqx_common_test_helpers:stop_apps([emqx_conf]),
     ok = emqx_connector_test_helpers:stop_apps([emqx_bridge, emqx_resource, emqx_rule_engine]),
     _ = application:stop(emqx_connector),
-    persistent_term:erase({emqx_bridge_gcp_pubsub_connector, transport}),
+    persistent_term:erase({emqx_bridge_gcp_pubsub_client, transport}),
     ok.
 
 init_per_group(sync_query, Config) ->