Require all MQTT feature flags and remove their compatibility code:
* delete_ra_cluster_mqtt_node
* rabbit_mqtt_qos0_queue
* mqtt_v5
These feature flags were introduced in or before 3.13.0.
This commit is a follow up of https://github.com/rabbitmq/rabbitmq-server/pull/11604
This commit changes the AMQP address format v2 from
```
/e/:exchange/:routing-key
/e/:exchange
/q/:queue
```
to
```
/exchanges/:exchange/:routing-key
/exchanges/:exchange
/queues/:queue
```
Advantages:
1. more user friendly
2. matches nicely with the plural forms of HTTP API v1 and HTTP API v2
This plural form is still non-overlapping with AMQP address format v1.
Although it might feel unusual at first to send a message to `/queues/q1`,
if you think about `queues` just being a namespace or entity type, this
address format makes sense.
to distinguish between v1 and v2 address formats.
Previously, v1 and v2 address formats overlapped and behaved differently
for example for:
```
/queue/:queue
/exchange/:exchange
```
This PR changes the v2 format to:
```
/e/:exchange/:routing-key
/e/:exchange
/q/:queue
```
to distinguish between v1 and v2 addresses.
This allows to call `rabbit_deprecated_features:is_permitted(amqp_address_v1)`
only if we know that the user requests address format v1.
Note that `rabbit_deprecated_features:is_permitted/1` should only
be called when the old feature is actually used.
Use percent encoding / decoding for address URI format v2.
This allows to use any UTF-8 encoded characters including slashes (`/`)
in routing keys, exchange names, and queue names and is more future
safe.
We don't need to duplicate so many patterns in so many
files since we have a monorepo (and want to keep it).
If I managed to miss something or remove something that
should stay, please put it back. Note that monorepo-wide
patterns should go in the top-level .gitignore file.
Other .gitignore files are for application or folder-
specific patterns.
* MQTT: speed up shared_SUITE:many_qos1_messages
* speed up block_only_publisher
* MQTT: reorganise tests groups
To avoid starting a new broker for each protocol group (v3,v4,v5).
Instead we run all protocol groups under a single cluster configuration
group.
* MQTT: speed up publish_to_all_queue_types_qos* tests.
* Remove separate mnesia_store group
to speed up the test suite
* Fix wrong_shard_count
* Remove unused field
* Run subset of v3 tests
The code being tested under v3 and v4 is almost identical.
To save time in CI, we therefore run only a very small subset of tests in v3.
This cuts the total time reported by CT for the shared_SUITE from 898
seconds to 614 seconds.
Also, the java_SUITE tests in v3.
* Fix wrong_shard_count
* Fix mixed version failure
---------
Co-authored-by: David Ansari <david.ansari@gmx.de>
## What?
Introduce RabbitMQ internal flow control for messages sent to AMQP
clients.
Prior this PR, when an AMQP client granted a large amount of link
credit (e.g. 100k) to the sending queue, the sending queue sent
that amount of messages to the session process no matter what.
This becomes problematic for memory usage when the session process
cannot send out messages fast enough to the AMQP client, especially if
1. The writer proc cannot send fast enough. This can happen when
the AMQP client does not receive fast enough and causes TCP
back-pressure to the server. Or
2. The server session proc is limited by remote-incoming-window.
Both scenarios are now added as test cases.
Tests
* tcp_back_pressure_rabbitmq_internal_flow_quorum_queue
* tcp_back_pressure_rabbitmq_internal_flow_classic_queue
cover scenario 1.
Tests
* incoming_window_closed_rabbitmq_internal_flow_quorum_queue
* incoming_window_closed_rabbitmq_internal_flow_classic_queue
cover scenario 2.
This PR sends messages from queues to AMQP clients in a more controlled
manner.
To illustrate:
```
make run-broker PLUGINS="rabbitmq_management" RABBITMQ_SERVER_ADDITIONAL_ERL_ARGS="+S 4"
observer_cli:start()
mq
```
where `mq` sorts by message queue length.
Create a stream:
```
deps/rabbitmq_management/bin/rabbitmqadmin declare queue name=s1 queue_type=stream durable=true
```
Next, send and receive from the Stream via AMQP.
Grant a large number of link credit to the sending stream:
```
docker run -it --rm --add-host host.docker.internal:host-gateway ssorj/quiver:latest
bash-5.1# quiver --version
quiver 0.4.0-SNAPSHOT
bash-5.1# quiver //host.docker.internal//queue/s1 --durable -d 30s --credit 100000
```
**Before** to this PR:
```
RESULTS
Count ............................................... 100,696 messages
Duration ............................................... 30.0 seconds
Sender rate ......................................... 120,422 messages/s
Receiver rate ......................................... 3,363 messages/s
End-to-end rate ....................................... 3,359 messages/s
```
We observe that all 100k link credit worth of messages are buffered in the
writer proc's mailbox:
```
|No | Pid | MsgQueue |Name or Initial Call | Memory | Reductions |Current Function |
|1 |<0.845.0> |100001 |rabbit_amqp_writer:init/1 | 126.0734 MB| 466633491 |prim_inet:send/5 |
```
**After** to this PR:
```
RESULTS
Count ............................................. 2,973,440 messages
Duration ............................................... 30.0 seconds
Sender rate ......................................... 123,322 messages/s
Receiver rate ........................................ 99,250 messages/s
End-to-end rate ...................................... 99,148 messages/s
```
We observe that the message queue lengths of both writer and session
procs are low.
## How?
Our goal is to have queues send out messages in a controlled manner
without overloading RabbitMQ itself.
We want RabbitMQ internal flow control between:
```
AMQP writer proc <--- session proc <--- queue proc
```
A similar concept exists for classic queues sending via AMQP 0.9.1.
We want an approach that applies to AMQP and works generic for all queue
types.
For the interaction between AMQP writer proc and session proc we use a
simple credit based approach reusing module `credit_flow`.
For the interaction between session proc and queue proc, the following options
exist:
### Option 1
The session process provides expliclity feedback to the queue after it
has sent N messages.
This approach is implemented in
https://github.com/ansd/rabbitmq-server/tree/amqp-flow-control-poc-1
and works well.
A new `rabbit_queue_type:sent/4` API was added which lets the queue proc know
that it can send further messages to the session proc.
Pros:
* Will work equally well for AMQP 0.9.1, e.g. when quorum queues send messages
in auto ack mode to AMQP 0.9.1 clients.
* Simple for the session proc
Cons:
* Sligthly added complexity in every queue type implementation
* Multiple Ra commands (settle, credit, sent) to decide when a quorum
queue sends more messages.
### Option 2
A dual link approach where two AMQP links exists between
```
AMQP client <---link--> session proc <---link---> queue proc
```
When the client grants a large amount of credits, the session proc will
top up credits to the queue proc periodically in smaller batches.
Pros:
* No queue type modifications required.
* Re-uses AMQP link flow control
Cons:
* Significant added complexity in the session proc. A client can
dynamically decrease or increase credits and dynamically change the drain
mode while the session tops up credit to the queue.
### Option 3
Credit is a 32 bit unsigned integer.
The spec mandates that the receiver independently chooses a credit.
Nothing in the spec prevents the receiver to choose a credit of 1 billion.
However the credit value is merely a **maximum**:
> The link-credit variable defines the current maximum legal amount that the delivery-count can be increased by.
Therefore, the server is not required to send all available messages to this
receiver.
For delivery-count:
> Only the sender MAY independently modify this field.
"independently" could be interpreted as the sender could add to the delivery-count
irrespective of what the client chose for drain and link-credit.
Option 3: The queue proc could at credit time already consume credit
and advance the delivery-count if credit is too large before checking out any messages.
For example if credit is 100k, but the queue only wants to send 1k, the queue could
consume 99k of credits and advance the delivery-count, and subsequently send maximum 1k messages.
If the queue advanced the delivery-count, RabbitMQ must send a FLOW to the receiver,
otherwise the receiver wouldn’t know that it ran out of link-credit.
Pros:
* Very simple
Cons:
* Possibly unexpected behaviour for receiving AMQP clients
* Possibly poor end-to-end throughput in auto-ack mode because the queue
would send a batch of messages followed by a FLOW containing the advanced
delivery-count. Only therafter the client will learn that it ran out of
credits and top-up again. This feels like synchronously pulling a batch
of messages. In contrast, option 2 sends out more messages as soon as
the previous messages left RabbitMQ without requiring again a credit top
up from the receiver.
* drain mode with large credits requires the queue to send all available
messages and only thereafter advance the delivery-count. Therefore,
drain mode breaks option 3 somewhat.
### Option 4
Session proc drops message payload when its outgoing-pending queue gets
too large and re-reads payloads from the queue once the message can be
sent (see `get_checked_out` Ra command for quorum queues).
Cons:
* Would need to be implemented for every queue type, especially classic queues
* Doesn't limit the amount of message metadata in the session proc's
outgoing-pending queue
### Decision: Option 2
This commit implements option 2 to avoid any queue type modification.
At most one credit request is in-flight between session process and
queue process for a given queue consumer.
If the AMQP client sends another FLOW in between, the session proc
stashes the FLOW until it processes the previous credit reply.
A delivery is only sent from the outgoing-pending queue if the
session proc is not blocked by
1. writer proc, or
2. remote-incoming-window
The credit reply is placed into the outgoing-pending queue.
This ensures that the session proc will only top up the next batch of
credits if sufficient messages were sent out to the writer proc.
A future commit could additionally have each queue limit the number of
unacked messages for a given AMQP consumer, or alternatively make use
of session outgoing-window.
Put configuration credit_flow_default_credit into persistent term such
that the tuple doesn't have to be copied on the hot path.
Also, change persistent term keys from `{rabbit, AtomKey}` to `AtomKey`
so that hashing becomes cheaper.
We reject CQv1 in rabbit.schema as well.
Most of the v1 code is still around as it is needed
for conversion to v2. It will be removed at a later
time when conversion is no longer supported.
We don't shard the CQ property suite anymore:
there's only 1 case remaining.
the `mc` module is ideally meant to be kept pure and portable
and feature flags have external infrastructure dependencies
as well as impure semantics.
Moving the check of this feature flag into the amqp session
simplifies the code (as no message containers with the new
format will enter the system before the feature flag is enabled).
Fixes#11171
An MQTT user encountered TLS handshake timeouts with their IoT device,
and the actual error from `ssl:handshake` / `ranch:handshake` was not
caught and logged.
At this time, `ranch` uses `exit(normal)` in the case of timeouts, but
that should change in the future
(https://github.com/ninenines/ranch/issues/336)
Similar to how we convert from mc_amqp to mc_amqpl before
sending to a classic queue or quorum queue process if
feature flag message_containers_store_amqp_v1 is disabled,
we also need to do the same conversion before sending to an MQTT QoS 0
queue on the old node.
Prior to this commit the entire amqp-value or amqp-sequence sections
were parsed when converting a message from mc_amqp.
Parsing the entire amqp-value or amqp-sequence section can generate a
huge amount of garbage depending on how large these sections are.
Given that other protocol cannot make use of amqp-value and
amqp-sequence sections anyway, leave them AMQP encoded when converting
from mc_amqp.
In fact prior to this commit, the entire body section was parsed
generating huge amounts of garbage just to subsequently encode it again
in mc_amqpl or mc_mqtt.
The new conversion interface from mc_amqp to other mc_* modules will
either output amqp-data sections or the encoded amqp-value /
amqp-sequence sections.
AMQP 3.2.1 defines durable=false to be the default.
However, the same section also mentions:
> If the header section is omitted the receiver MUST assume the appropriate
> default values (or the meaning implied by no value being set) for the
> fields within the header unless other target or node specific defaults
> have otherwise been set.
We want RabbitMQ to be secure by default, hence in RabbitMQ we set
durable=true to be the default.
This commit fixes test
```
bazel test //deps/rabbitmq_mqtt:shared_SUITE-mixed -t- \
--test_sharding_strategy=disabled --test_env \
FOCUS="-group [mqtt,v3,cluster_size_3] -case pubsub"
```
Fix some mixed version tests
Assume the AMQP body, especially amqp-value section won't be parsed.
Hence, omit smart conversions from AMQP to MQTT involving the
Payload-Format-Indicator bit.
Fix test
Fix
```
bazel test //deps/amqp10_client:system_SUITE-mixed -t- --test_sharding_strategy=disabled --test_env FOCUS="-group [rabbitmq]
```
This is a follow up to https://github.com/rabbitmq/rabbitmq-server/pull/11012
## What?
For incoming MQTT messages, always set the `durable` message container
annotation.
## Why?
Even though defaulting to `durable=true` when no durable annotation is
set, as prior to this commit, is good enough, explicitly setting the
durable annotation makes the code a bit more future proof and
maintainable going forward in 4.0 where we will rely more on the durable
annotation because AMQP 1.0 message headers will be omitted in classic
and quorum queues (see https://github.com/rabbitmq/rabbitmq-server/pull/10964)
For MQTT messages, it's important to know whether the message was
published with QoS 0 or QoS 1 because it affects the QoS for the MQTT
message that will delivered to the MQTT subscriber.
The performance impact of always setting the durable annotation is
negligible.
Resolves https://github.com/rabbitmq/rabbitmq-server/discussions/11021
Prior to this commit, an MQTT client that connects to RabbitMQ needed
configure access to its will queue even if the will queue has never
existed. This breaks client apps connecting with either v3 or v4 or with
v5 without making use of the Will-Delay-Interval.
Specifically, in 3.13.0 and 3.13.1 an MQTT client that connects to
RabbitMQ needs unnecessarily configure access to queue
`mqtt-will-<MQTT client ID>`.
This commit only check for configure access, if the queue actually gets
deleted, i.e. if it existed.
By default, when the 'durable' message container (mc) annotation is unset,
messages are interpreted to be durable.
Prior to this commit, MQTT messages that were sent with QoS 0 were
stored durably in classic queues.
This commit takes the same approach for mc_mqtt as for mc_amqpl and mc_amqp:
If the message is durable, the durable mc annotation will not be set.
If the message is non-durable, the durable mc annotation will be set to false.
When feature flag message_containers is enabled, setting
```
message_interceptors.incoming.set_header_timestamp
```
wasn't respected anymore when a message is published via MQTT to a
stream and subsequently consumed via AMQP 0.9.1.
This commit ensures that AMQP 0.9.1 header timestamp_in_ms will be
set.
Note that we must not modify the AMQP 1.0 properties section when messages
are received via AMQP 1.0 and consumed via AMQP 1.0.
Also, message annoation keys not starting with "x-" are reserved.
## What?
Introduce a new address format (let's call it v2) for AMQP 1.0 source and target addresses.
The old format (let's call it v1) is described in
https://github.com/rabbitmq/rabbitmq-server/tree/v3.13.x/deps/rabbitmq_amqp1_0#routing-and-addressing
The only v2 source address format is:
```
/queue/:queue
```
The 4 possible v2 target addresses formats are:
```
/exchange/:exchange/key/:routing-key
/exchange/:exchange
/queue/:queue
<null>
```
where the last AMQP <null> value format requires that each message’s `to` field contains one of:
```
/exchange/:exchange/key/:routing-key
/exchange/:exchange
/queue/:queue
```
## Why?
The AMQP address v1 format comes with the following flaws:
1. Obscure address format:
Without reading the documentation, the differences for example between source addresses
```
/amq/queue/:queue
/queue/:queue
:queue
```
are unknown to users. Hence, the address format is obscure.
2. Implicit creation of topologies
Some address formats implicitly create queues (and bindings), such as source address
```
/exchange/:exchange/:binding-key
```
or target address
```
/queue/:queue
```
These queues and bindings are never deleted (by the AMQP 1.0 plugin.)
Implicit creation of such topologies is also obscure.
3. Redundant address formats
```
/queue/:queue
:queue
```
have the same meaning and are therefore redundant.
4. Properties section must be parsed to determine whether a routing key is present
Target address
```
/exchange/:exchange
```
requires RabbitMQ to parse the properties section in order to check whether the message `subject` is set.
If `subject` is not set, the routing key will default to the empty string.
5. Using `subject` as routing key misuses the purpose of this field.
According to the AMQP spec, the message `subject` field's purpose is:
> A common field for summary information about the message content and purpose.
6. Exchange names, queue names and routing keys must not contain the "/" (slash) character.
The current 3.13 implemenation splits by "/" disallowing these
characters in exchange, and queue names, and routing keys which is
unnecessary prohibitive.
7. Clients must create a separate link per target exchange
While this is reasonable working assumption, there might be rare use
cases where it could make sense to create many exchanges (e.g. 1
exchange per queue, see
https://github.com/rabbitmq/rabbitmq-server/discussions/10708) and have
a single application publish to all these exchanges.
With the v1 address format, for an application to send to 500 different
exchanges, it needs to create 500 links.
Due to these disadvantages and thanks to #10559 which allows clients to explicitly create topologies,
we can create a simpler, clearer, and better v2 address format.
## How?
### Design goals
Following the 7 cons from v1, the design goals for v2 are:
1. The address format should be simple so that users have a chance to
understand the meaning of the address without necessarily consulting the docs.
2. The address format should not implicitly create queues, bindings, or exchanges.
Instead, topologies should be created either explicitly via the new management node
prior to link attachment (see #10559), or in future, we might support the `dynamic`
source or target properties so that RabbitMQ creates queues dynamically.
3. No redundant address formats.
4. The target address format should explicitly state whether the routing key is present, empty,
or will be provided dynamically in each message.
5. `Subject` should not be used as routing key. Instead, a better
fitting field should be used.
6. Exchange names, queue names, and routing keys should allow to contain
valid UTF-8 encoded data including the "/" character.
7. Allow both target exchange and routing key to by dynamically provided within each message.
Furthermore
8. v2 must co-exist with v1 for at least some time. Applications should be able to upgrade to
RabbitMQ 4.0 while continuing to use v1. Examples include AMQP 1.0 shovels and plugins communicating
between a 4.0 and a 3.13 cluster. Starting with 4.1, we should change the AMQP 1.0 shovel and plugin clients
to use only the new v2 address format. This will allow AMQP 1.0 and plugins to communicate between a 4.1 and 4.2 cluster.
We will deprecate v1 in 4.0 and remove support for v1 in a later 4.x version.
### Additional Context
The address is usually a String, but can be of any type.
The [AMQP Addressing extension](https://docs.oasis-open.org/amqp/addressing/v1.0/addressing-v1.0.html)
suggests that addresses are URIs and are therefore hierarchical and could even contain query parameters:
> An AMQP address is a URI reference as defined by RFC3986.
> the path expression is a sequence of identifier segments that reflects a path through an
> implementation specific relationship graph of AMQP nodes and their termini.
> The path expression MUST resolve to a node’s terminus in an AMQP container.
The [Using the AMQP Anonymous Terminus for Message Routing Version 1.0](https://docs.oasis-open.org/amqp/anonterm/v1.0/cs01/anonterm-v1.0-cs01.html)
extension allows for the target being `null` and the `To` property to contain the node address.
This corresponds to AMQP 0.9.1 where clients can send each message on the same channel to a different `{exchange, routing-key}` destination.
The following v2 address formats will be used.
### v2 addresses
A new deprecated feature flag `amqp_address_v1` will be introduced in 4.0 which is permitted by default.
Starting with 4.1, we should change the AMQP 1.0 shovel and plugin AMQP 1.0 clients to use only the new v2 address format.
However, 4.1 server code must still understand the 4.0 AMQP 1.0 shovel and plugin AMQP 1.0 clients’ v1 address format.
The new deprecated feature flag will therefore be denied by default in 4.2.
This allows AMQP 1.0 shovels and plugins to work between
* 4.0 and 3.13 clusters using v1
* 4.1 and 4.0 clusters using v2 from 4.1 to v4.0 and v1 from 4.0 to 4.1
* 4.2 and 4.1 clusters using v2
without having to support both v1 and v2 at the same time in the AMQP 1.0 shovel and plugin clients.
While supporting both v1 and v2 in these clients is feasible, it's simpler to switch the client code directly from v1 to v2.
### v2 source addresses
The source address format is
```
/queue/:queue
```
If the deprecated feature flag `amqp_address_v1` is permitted and the queue does not exist, the queue will be auto-created.
If the deprecated feature flag `amqp_address_v1` is denied, the queue must exist.
### v2 target addresses
v1 requires attaching a new link for each destination exchange.
v2 will allow dynamic `{exchange, routing-key}` combinations for a given link.
v2 therefore allows for the rare use cases where a single AMQP 1.0 publisher app needs to send to many different exchanges.
Setting up a link per destination exchange could be cumbersome.
Hence, v2 will support the dynamic `{exchange, routing-key}` combinations of AMQP 0.9.1.
To achieve this, we make use of the "Anonymous Terminus for Message Routing" extension:
The target address will contain the AMQP value null.
The `To` field in each message must be set and contain either address format
```
/exchange/:exchange/key/:routing-key
```
or
```
/exchange/:exchange
```
when using the empty routing key.
The `to` field requires an address type and is better suited than the `subject field.
Note that each message will contain this `To` value for the anonymous terminus.
Hence, we should save some bytes being sent across the network and stored on disk.
Using a format
```
/e/:exchange/k/:routing-key
```
saves more bytes, but is too obscure.
However, we use only `/key/` instead of `/routing-key/` so save a few bytes.
This also simplifies the format because users don’t have to remember whether to use spell `routing-key` or `routing_key` or `routingkey`.
The other allowed target address formats are:
```
/exchange/:exchange/key/:routing-key
```
where exchange and routing key are static on the given link.
```
/exchange/:exchange
```
where exchange and routing key are static on the given link, and routing key will be the empty string (useful for example for the fanout exchange).
```
/queue/:queue
```
This provides RabbitMQ beginners the illusion of sending a message directly
to a queue without having to understand what exchanges and routing keys are.
If the deprecated feature flag `amqp_address_v1` is permitted and the queue does not exist, the queue will be auto-created.
If the deprecated feature flag `amqp_address_v1` is denied, the queue must exist.
Besides the additional queue existence check, this queue target is different from
```
/exchange//key/:queue
```
in that queue specific optimisations might be done (in future) by RabbitMQ
(for example different receiving queue types could grant different amounts of link credits to the sending clients).
A write permission check to the amq.default exchange will be performed nevertheless.
v2 will prohibit the v1 static link & dynamic routing-key combination
where the routing key is sent in the message `subject` as that’s also obscure.
For this use case, v2’s new anonymous terminus can be used where both exchange and routing key are defined in the message’s `To` field.
(The bare message must not be modified because it could be signed.)
The alias format
```
/topic/:topic
```
will also be removed.
Sending to topic exchanges is arguably an advanced feature.
Users can directly use the format
```
/exchange/amq.topic/key/:topic
```
which reduces the number of redundant address formats.
### v2 address format reference
To sump up (and as stated at the top of this commit message):
The only v2 source address format is:
```
/queue/:queue
```
The 4 possible v2 target addresses formats are:
```
/exchange/:exchange/key/:routing-key
/exchange/:exchange
/queue/:queue
<null>
```
where the last AMQP <null> value format requires that each message’s `to` field contains one of:
```
/exchange/:exchange/key/:routing-key
/exchange/:exchange
/queue/:queue
```
Hence, all 8 listed design goals are reached.
The Web MQTT link is not used in the rabbitmq_mqtt Erlang app.
This link is only used in the rabbitmq_web_mqtt Erlang app.
Hence, move the link to the correct Erlang app.
PR #10761 added a new CLI command to list Web MQTT connections.
That new CLI command relies on feature flag delete_ra_cluster_mqtt_node
being enabled.
This commit ensures exactly this condition.