It's not used. Also, the callback shall run completely at once. This ensures that it won't (continue to) run once another coroutine on the strand calls Timeout#Cancel().
The reason for introducing AsioTlsStream::GracefulDisconnect() was to handle
the TLS shutdown properly with a timeout since it involves a timeout. However,
the implementation of this timeout involves spwaning coroutines which are
redundant in some cases. This commit adds comments to the remaining calls of
async_shutdown() stating why calling it is safe in these places.
Calling `AsioTlsStream::async_shutdown()` performs a TLS shutdown which
exchanges messages (that's why it takes a `yield_context`) and thus has the
potential to block the coroutine. Therefore, it should be protected with a
timeout. As `async_shutdown()` doesn't simply take a timeout, this has to be
implemented using a timer. So far, these timers are scattered throughout the
codebase with some places missing them entirely. This commit adds helper
functions to properly shutdown a TLS connection with a single function call.
The .ti files call `DependencyGraph::AddDependency(this, service.get())`. Obviously, `service.get()` is the parent and `this` (Downtime, Notification, ...) is the child. The DependencyGraph terminology should reflect this not to confuse its future users.
Currently, for each `Disconnect()` call, we spawn a coroutine, but every
one of them is just usesless, except the first one. However, since all
`Disconnect()` usages share the same asio strand and cannot interfere
with each other, spawning another coroutine within `Disconnect()` isn't
even necessary. When a coroutine calls `Disconnect()` now, it will
immediately initiate an async shutdown of the socket, potentially causing
the coroutine to yield and allowing the others to resume. Therefore, the
`m_ShuttingDown` flag is still required by the coroutines to be checked
regularly.
In fact, this is already done for the outer loop (for each bulk), just not yet for the inner one (for each message of a bulk). So once the remote signals EOF, don't try to process the remaining queue until write error (which can't be associated with a particular message anyway, due to buffering), but just let the peer go. Flush already half-written messages, though, if possible.
by not calling `std::atomic<T>::atomic(void)`.
After the latter the instance "does not contain a T object, and its only valid uses are destruction and initialization by std::atomic_init" which we don't call. So the only safe option is `std::atomic<T>::atomic(T)`.
https://en.cppreference.com/w/cpp/atomic/atomic/atomic
When the `Desconnect()` method is called, clients are not disconnected
immediately. Instead, a new coroutine is spawned using the same strand
as the other coroutines. This coroutine calls `async_shutdown` on the
TCP socket, which might be blocking. However, in order not to block
indefintely, the `Timeout` class cancels all operations on the socket
after `10` seconds. Though, the timeout does not trigger the handler
immediately; it creates spawns another coroutine using the same strand
as in the `JsonRpcConnection` class. This can cause unexpected delays if
e.g. `HandleIncomingMessages` gets resumed before the coroutine from the
timeout class. Apart from that, the coroutine for writing messages uses
the same condition, making the two symmetrical.
Something is definitely going wrong if a client tries to reconnect to
this endpoint while it still has an active connection to that client. So
we shouldn't hide this, but at least log it at info level. Apart from
that, I've added some additional information about the currently active
client, such as when the last message was sent and received.
The Redis ACL system was introduced with Redis 6.0. It introduced users
with precisely granular permissions. This change allows Icinga 2 to use
the Icinga DB feature against a Redis with an ACL user.
This was reflected in the documentation, next to the already
implemented, but undocumented Redis database.
Closes#9536.
Each configuration field of an IcingaDB Object was marked with
no_user_modify as modifications via the API would not result in an
actual change. While the Object would be updated, the internal Redis
connection would not be restarted, resulting in an unexpected behavior.
The missing db_index was added to the documentation.
Alexander A. Klimov
Julian Brost
Yonas Habteab
Julian Brost
Alvar Penning