[cdc_stream] Add wildcard support to stop command (#30)

Adds support for stuff like cdc_stream stop * or cdc_stream stop user*:dir*.

README.md

@@ -224,6 +224,11 @@ To stop the streaming session, enter
 ```
 cdc_stream stop user@linux.device.com:~/assets
 ```
+The command also accepts wildcards. For instance, 
+```
+cdc_stream stop user@*:*
+```
+stops all existing streaming sessions for the given user.
 
 ## Troubleshooting
 

cdc_stream/BUILD

@@ -208,6 +208,7 @@ cc_library(
         "//common:file_watcher",
         "//common:log",
         "//common:path",
+        "//common:path_filter",
         "//common:port_manager",
         "//common:process",
         "//common:remote_util",

cdc_stream/multi_session.cc

@@ -18,6 +18,7 @@
 #include "common/file_watcher_win.h"
 #include "common/log.h"
 #include "common/path.h"
+#include "common/path_filter.h"
 #include "common/platform.h"
 #include "common/port_manager.h"
 #include "common/process.h"
@@ -555,6 +556,21 @@ bool MultiSession::HasSession(const std::string& instance_id) {
   return sessions_.find(instance_id) != sessions_.end();
 }
 
+std::vector<std::string> MultiSession::MatchSessions(
+    const std::string& instance_id_filter) {
+  PathFilter filter;
+  filter.AddRule(PathFilter::Rule::Type::kInclude, instance_id_filter);
+  filter.AddRule(PathFilter::Rule::Type::kExclude, "*");
+
+  std::vector<std::string> matches;
+  for (const auto& [instance_id, session] : sessions_) {
+    if (filter.IsMatch(instance_id)) {
+      matches.push_back(instance_id);
+    }
+  }
+  return matches;
+}
+
 bool MultiSession::IsSessionHealthy(const std::string& instance_id) {
   absl::ReaderMutexLock lock(&sessions_mutex_);
   auto iter = sessions_.find(instance_id);

cdc_stream/multi_session.h

@@ -194,6 +194,11 @@ class MultiSession {
   absl::Status StopSession(const std::string& instance_id)
       ABSL_LOCKS_EXCLUDED(sessions_mutex_);
 
+  // Returns all instance ids that match the given filter. The filter may
+  // contain Windows-style wildcards, e.g. *, foo* or f?o.
+  // Matches are case sensitive.
+  std::vector<std::string> MatchSessions(const std::string& instance_id_filter);
+
   // Returns true if there is an existing session for |instance_id|.
   bool HasSession(const std::string& instance_id)
       ABSL_LOCKS_EXCLUDED(sessions_mutex_);

cdc_stream/session_manager.cc

@@ -136,9 +136,24 @@ absl::Status SessionManager::StartSession(
   return status;
 }
 
-absl::Status SessionManager::StopSession(const std::string& instance_id) {
+absl::Status SessionManager::StopSession(
+    const std::string& instance_id_filter) {
   absl::MutexLock lock(&sessions_mutex_);
-  return StopSessionInternal(instance_id);
+
+  std::vector<std::string> instance_ids;
+  for (const auto& [key, ms] : sessions_) {
+    auto ids = ms->MatchSessions(instance_id_filter);
+    instance_ids.insert(instance_ids.end(), ids.begin(), ids.end());
+  }
+  if (instance_ids.empty()) {
+    return absl::NotFoundError(
+        absl::StrFormat("No session found matching '%s'", instance_id_filter));
+  }
+
+  for (const std::string& instance_id : instance_ids) {
+    RETURN_IF_ERROR(StopSessionInternal(instance_id));
+  }
+  return absl::OkStatus();
 }
 
 MultiSession* SessionManager::GetMultiSession(const std::string& src_dir) {

cdc_stream/session_manager.h

@@ -58,9 +58,11 @@ class SessionManager {
                             metrics::SessionStartStatus* metrics_status)
       ABSL_LOCKS_EXCLUDED(sessions_mutex_);
 
-  // Stops the session for the given |instance_id|.
+  // Stops all sessions that match the given |instance_id_filter|.
+  // The filter may contain Windows-style wildcards like * and ?.
+  // Matching is case-sensitive.
   // Returns a NotFound error if no session exists.
-  absl::Status StopSession(const std::string& instance_id)
+  absl::Status StopSession(const std::string& instance_id_filter)
       ABSL_LOCKS_EXCLUDED(sessions_mutex_);
 
   // Shuts down all existing MultiSessions.

cdc_stream/start_command.cc

@@ -101,7 +101,7 @@ void StartCommand::RegisterCommandLineFlags(lyra::command& cmd) {
                        .help("Windows directory to stream"));
 
   cmd.add_argument(
-      lyra::arg(PosArgValidator(&user_host_dir_), "[user@]host:src-dir")
+      lyra::arg(PosArgValidator(&user_host_dir_), "[user@]host:dir")
           .required()
           .help("Linux host and directory to stream to"));
 }

cdc_stream/stop_command.cc

@@ -53,7 +53,7 @@ void StopCommand::RegisterCommandLineFlags(lyra::command& cmd) {
                 std::to_string(SessionManagementServer::kDefaultServicePort)));
 
   cmd.add_argument(
-      lyra::arg(PosArgValidator(&user_host_dir_), "[user@]host:src-dir")
+      lyra::arg(PosArgValidator(&user_host_dir_), "[user@]host:dir")
           .required()
           .help("Linux host and directory to stream to"));
 }
@@ -70,8 +70,14 @@ absl::Status StopCommand::Run() {
   LocalAssetsStreamManagerClient client(channel);
 
   std::string user_host, mount_dir;
-  RETURN_IF_ERROR(LocalAssetsStreamManagerClient::ParseUserHostDir(
-      user_host_dir_, &user_host, &mount_dir));
+  if (user_host_dir_ == "*") {
+    // Convenience shortcut "*" for "*:*".
+    user_host = "*";
+    mount_dir = "*";
+  } else {
+    RETURN_IF_ERROR(LocalAssetsStreamManagerClient::ParseUserHostDir(
+        user_host_dir_, &user_host, &mount_dir));
+  }
 
   absl::Status status = client.StopSession(user_host, mount_dir);
   if (status.ok()) {

proto/local_assets_stream_manager.proto

@@ -65,9 +65,10 @@ message StopSessionRequest {
   // ID of assets streaming target gamelet.
   // Only used by Stadia. Should set either this or user_host_dir.
   string gamelet_id = 1;
-  // Username and host, in the form [user@]host.
+  // Username and host, in the form [user@]host. Accepts wildcards * and ?.
   string user_host = 2;
   // Remote directory where the streamed directory is mounted.
+  // Accepts wildcards * and ?.
   string mount_dir = 3;
 }