api: reference httpd::* symbols like 'httpd::*'

it turns out we have `using namespace httpd;` in seastar's
`request_parser.rl`, and we should not rely on this statement to
expose the symbols in `seatar::httpd` to `seastar` namespace.
in this change,

* api/*.hh: all httpd symbols are referenced by `httpd::*`
  instead of being referenced as if they are in `seastar`.
* api/*.cc: add `using namespace seastar::httpd`.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>

api/api.cc

@@ -35,6 +35,7 @@
 logging::logger apilog("api");
 
 namespace api {
+using namespace seastar::httpd;
 
 static std::unique_ptr<reply> exception_reply(std::exception_ptr eptr) {
     try {

api/authorization_cache.cc

@@ -14,6 +14,7 @@
 
 namespace api {
 using namespace json;
+using namespace seastar::httpd;
 
 void set_authorization_cache(http_context& ctx, routes& r, sharded<auth::service> &auth_service) {
     httpd::authorization_cache_json::authorization_cache_reset.set(r, [&auth_service] (std::unique_ptr<http::request> req) -> future<json::json_return_type> {

api/cache_service.cc

@@ -12,6 +12,7 @@
 
 namespace api {
 using namespace json;
+using namespace seastar::httpd;
 namespace cs = httpd::cache_service_json;
 
 void set_cache_service(http_context& ctx, routes& r) {

api/commitlog.cc

@@ -13,6 +13,7 @@
 #include <vector>
 
 namespace api {
+using namespace seastar::httpd;
 
 template<typename T>
 static auto acquire_cl_metric(http_context& ctx, std::function<T (db::commitlog*)> func) {

api/config.cc

@@ -13,6 +13,7 @@
 #include <boost/algorithm/string/replace.hpp>
 
 namespace api {
+using namespace seastar::httpd;
 
 template<class T>
 json::json_return_type get_json_return_type(const T& val) {

api/endpoint_snitch.cc

@@ -15,6 +15,7 @@
 #include "utils/fb_utilities.hh"
 
 namespace api {
+using namespace seastar::httpd;
 
 void set_endpoint_snitch(http_context& ctx, routes& r, sharded<locator::snitch_ptr>& snitch) {
     static auto host_or_broadcast = [](const_req req) {

api/error_injection.cc

@@ -15,6 +15,7 @@
 #include <seastar/core/future-util.hh>
 
 namespace api {
+using namespace seastar::httpd;
 
 namespace hf = httpd::error_injection_json;
 

api/failure_detector.cc

@@ -11,7 +11,9 @@
 #include "gms/failure_detector.hh"
 #include "gms/application_state.hh"
 #include "gms/gossiper.hh"
+
 namespace api {
+using namespace seastar::httpd;
 
 namespace fd = httpd::failure_detector_json;
 

api/gossiper.cc

@@ -11,6 +11,7 @@
 #include "gms/gossiper.hh"
 
 namespace api {
+using namespace seastar::httpd;
 using namespace json;
 
 void set_gossiper(http_context& ctx, routes& r, gms::gossiper& g) {

api/hinted_handoff.cc

@@ -19,6 +19,7 @@
 namespace api {
 
 using namespace json;
+using namespace seastar::httpd;
 namespace hh = httpd::hinted_handoff_json;
 
 void set_hinted_handoff(http_context& ctx, routes& r, gms::gossiper& g) {

api/lsa.cc

@@ -16,6 +16,7 @@
 #include "replica/database.hh"
 
 namespace api {
+using namespace seastar::httpd;
 
 static logging::logger alogger("lsa-api");
 

api/messaging_service.cc

@@ -13,6 +13,7 @@
 #include <iostream>
 #include <sstream>
 
+using namespace seastar::httpd;
 using namespace httpd::messaging_service_json;
 using namespace netw;
 

api/storage_proxy.cc

@@ -20,6 +20,7 @@ namespace api {
 
 namespace sp = httpd::storage_proxy_json;
 using proxy = service::storage_proxy;
+using namespace seastar::httpd;
 using namespace json;
 
 utils::time_estimated_histogram timed_rate_moving_average_summary_merge(utils::time_estimated_histogram a, const utils::timed_rate_moving_average_summary_and_histogram& b) {

api/storage_service.cc

@@ -47,6 +47,9 @@
 #include "sstables_loader.hh"
 #include "db/view/view_builder.hh"
 
+using namespace seastar::httpd;
+using namespace std::chrono_literals;
+
 extern logging::logger apilog;
 
 namespace std {

api/stream_manager.cc

@@ -14,6 +14,7 @@
 #include "gms/gossiper.hh"
 
 namespace api {
+using namespace seastar::httpd;
 
 namespace hs = httpd::stream_manager_json;
 

api/system.cc

@@ -17,6 +17,7 @@
 extern logging::logger apilog;
 
 namespace api {
+using namespace seastar::httpd;
 
 namespace hs = httpd::system_json;
 

api/task_manager.cc

@@ -22,6 +22,7 @@ namespace api {
 
 namespace tm = httpd::task_manager_json;
 using namespace json;
+using namespace seastar::httpd;
 
 inline bool filter_tasks(tasks::task_manager::task_ptr task, std::unordered_map<sstring, sstring>& query_params) {
     return (!query_params.contains("keyspace") || query_params["keyspace"] == task->get_status().keyspace) &&

api/task_manager_test.cc

@@ -18,6 +18,7 @@ namespace api {
 
 namespace tmt = httpd::task_manager_test_json;
 using namespace json;
+using namespace seastar::httpd;
 
 void set_task_manager_test(http_context& ctx, routes& r) {
     tmt::register_test_module.set(r, [&ctx] (std::unique_ptr<http::request> req) -> future<json::json_return_type> {