Class: WaterDrop::Producer
- Inherits:
-
Object
- Object
- WaterDrop::Producer
- Extended by:
- Forwardable
- Includes:
- Karafka::Core::Helpers::Time, Karafka::Core::Taggable, Async, Buffer, Sync, Transactions
- Defined in:
- lib/waterdrop/producer.rb,
lib/waterdrop/producer/sync.rb,
lib/waterdrop/producer/async.rb,
lib/waterdrop/producer/buffer.rb,
lib/waterdrop/producer/status.rb,
lib/waterdrop/producer/builder.rb,
lib/waterdrop/producer/variant.rb,
lib/waterdrop/producer/transactions.rb
Overview
Main WaterDrop messages producer
Defined Under Namespace
Modules: Async, Buffer, Sync, Transactions Classes: Builder, Status, Variant
Instance Attribute Summary collapse
-
#config ⇒ Object
readonly
Dry-configurable config object.
-
#id ⇒ String
readonly
Uuid of the current producer.
-
#messages ⇒ Array
readonly
Internal messages buffer.
-
#monitor ⇒ Object
readonly
Monitor we want to use.
-
#status ⇒ Status
readonly
Producer status object.
Instance Method Summary collapse
-
#client ⇒ Rdkafka::Producer
Raw rdkafka producer.
-
#close(force: false) ⇒ Object
Flushes the buffers in a sync way and closes the producer.
-
#close! ⇒ Object
Closes the producer with forced close after timeout, purging any outgoing data.
-
#disconnect ⇒ Boolean
Disconnects the producer from Kafka while keeping it configured for potential reconnection.
-
#disconnectable? ⇒ Boolean
Is the producer in a state from which we can disconnect.
-
#idempotent? ⇒ Boolean
True if current producer is idempotent.
-
#initialize(&block) ⇒ Producer
constructor
Creates a not-yet-configured instance of the producer.
-
#inspect ⇒ String
Mutex-safe inspect details.
-
#middleware ⇒ WaterDrop::Producer::Middleware
Returns and caches the middleware object that may be used.
-
#partition_count(topic) ⇒ Integer
Fetches and caches the partition count of a topic.
-
#purge ⇒ Object
Purges data from both the buffer queue as well as the librdkafka queue.
-
#setup(&block) ⇒ Object
Sets up the whole configuration and initializes all that is needed.
-
#with(**args) ⇒ WaterDrop::Producer::Variant
(also: #variant)
Builds the variant alteration and returns it.
Methods included from Transactions
#transaction, #transaction?, #transaction_mark_as_consumed, #transactional?
Methods included from Buffer
#buffer, #buffer_many, #flush_async, #flush_sync
Methods included from Async
#produce_async, #produce_many_async
Methods included from Sync
#produce_many_sync, #produce_sync
Constructor Details
#initialize(&block) ⇒ Producer
Creates a not-yet-configured instance of the producer
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# File 'lib/waterdrop/producer.rb', line 47 def initialize(&block) @operations_in_progress = Helpers::Counter.new @buffer_mutex = Mutex.new @connecting_mutex = Mutex.new @operating_mutex = Mutex.new @transaction_mutex = Mutex.new @id = nil @monitor = nil @contract = nil @default_variant = nil @client = nil @closing_thread_id = nil @status = Status.new @messages = [] return unless block setup(&block) end |
Instance Attribute Details
#config ⇒ Object (readonly)
Returns dry-configurable config object.
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# File 'lib/waterdrop/producer.rb', line 42 def config @config end |
#id ⇒ String (readonly)
Returns uuid of the current producer.
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# File 'lib/waterdrop/producer.rb', line 34 def id @id end |
#messages ⇒ Array (readonly)
Returns internal messages buffer.
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# File 'lib/waterdrop/producer.rb', line 38 def @messages end |
#monitor ⇒ Object (readonly)
Returns monitor we want to use.
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# File 'lib/waterdrop/producer.rb', line 40 def monitor @monitor end |
#status ⇒ Status (readonly)
Returns producer status object.
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# File 'lib/waterdrop/producer.rb', line 36 def status @status end |
Instance Method Details
#client ⇒ Rdkafka::Producer
Client is lazy initialized, keeping in mind also the fact of a potential fork that can happen any time.
It is not recommended to fork a producer that is already in use so in case of bootstrapping a cluster, it’s much better to fork configured but not used producers
Returns raw rdkafka producer.
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# File 'lib/waterdrop/producer.rb', line 102 def client return @client if @client && @pid == Process.pid # Don't allow to obtain a client reference for a producer that was not configured raise Errors::ProducerNotConfiguredError, id if @status.initial? raise Errors::ProducerClosedError, id if @status.closed? @connecting_mutex.synchronize do return @client if @client && @pid == Process.pid # We undefine all the finalizers, in case it was a fork, so the finalizers from the parent # process don't leak ObjectSpace.undefine_finalizer(id) # We should raise an error when trying to use a producer with client from a fork. Always. if @client # We need to reset the client, otherwise there might be attempt to close the parent # client @client = nil raise Errors::ProducerUsedInParentProcess, Process.pid end # Finalizer tracking is needed for handling shutdowns gracefully. # I don't expect everyone to remember about closing all the producers all the time, thus # this approach is better. Although it is still worth keeping in mind, that this will # block GC from removing a no longer used producer unless closed properly but at least # won't crash the VM upon closing the process ObjectSpace.define_finalizer(id, proc { close }) @pid = Process.pid @client = Builder.new.call(self, @config) @status.connected! @monitor.instrument('producer.connected', producer_id: id) end @client end |
#close(force: false) ⇒ Object
Flushes the buffers in a sync way and closes the producer
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# File 'lib/waterdrop/producer.rb', line 270 def close(force: false) # If we already own the transactional mutex, it means we are inside of a transaction and # it should not we allowed to close the producer in such a case. if @transaction_mutex.locked? && @transaction_mutex.owned? raise Errors::ProducerTransactionalCloseAttemptError, id end # The transactional mutex here can be used even when no transactions are in use # It prevents us from closing a mutex during transactions and is irrelevant in other cases @transaction_mutex.synchronize do @operating_mutex.synchronize do return unless @status.active? @monitor.instrument( 'producer.closed', producer_id: id ) do @status.closing! @monitor.instrument('producer.closing', producer_id: id) # No need for auto-gc if everything got closed by us # This should be used only in case a producer was not closed properly and forgotten ObjectSpace.undefine_finalizer(id) # We save this thread id because we need to bypass the activity verification on the # producer for final flush of buffers. @closing_thread_id = Thread.current.object_id # Wait until all the outgoing operations are done. Only when no one is using the # underlying client running operations we can close sleep(0.001) until @operations_in_progress.value.zero? # Flush has its own buffer mutex but even if it is blocked, flushing can still happen # as we close the client after the flushing (even if blocked by the mutex) flush(true) # We should not close the client in several threads the same time # It is safe to run it several times but not exactly the same moment # We also mark it as closed only if it was connected, if not, it would trigger a new # connection that anyhow would be immediately closed if @client # Why do we trigger it early instead of just having `#close` do it? # The linger.ms time will be ignored for the duration of the call, # queued messages will be sent to the broker as soon as possible. begin @client.flush(current_variant.max_wait_timeout) unless @client.closed? # We can safely ignore timeouts here because any left outstanding requests # will anyhow force wait on close if not forced. # If forced, we will purge the queue and just close rescue ::Rdkafka::RdkafkaError, Rdkafka::AbstractHandle::WaitTimeoutError nil ensure # Purge fully the local queue in case of a forceful shutdown just to be sure, that # there are no dangling messages. In case flush was successful, there should be # none but we do it just in case it timed out purge if force end @client.close @client = nil end # Remove callbacks runners that were registered ::Karafka::Core::Instrumentation.statistics_callbacks.delete(@id) ::Karafka::Core::Instrumentation.error_callbacks.delete(@id) ::Karafka::Core::Instrumentation.oauthbearer_token_refresh_callbacks.delete(@id) @status.closed! end end end end |
#close! ⇒ Object
Closes the producer with forced close after timeout, purging any outgoing data
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# File 'lib/waterdrop/producer.rb', line 345 def close! close(force: true) end |
#disconnect ⇒ Boolean
This method will refuse to disconnect if: - There are pending messages in the internal buffer - There are operations currently in progress - A transaction is currently active - The client is not currently connected - Required mutexes are locked by other operations
After successful disconnection, the producer status changes to disconnected but remains configured, allowing for future reconnection when client access is needed.
Disconnects the producer from Kafka while keeping it configured for potential reconnection
This method safely disconnects the underlying Kafka client while preserving the producer’s
configuration. Unlike #close
, this allows the producer to be reconnected later by calling
methods that require the client. The disconnection will only proceed if certain safety
conditions are met.
This API can be used to preserve connections on low-intensity producer instances, etc.
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# File 'lib/waterdrop/producer.rb', line 221 def disconnect return false unless disconnectable? # Use the same mutex pattern as the regular close method to prevent race conditions @transaction_mutex.synchronize do @operating_mutex.synchronize do @buffer_mutex.synchronize do return false unless @client return false unless @status.connected? return false unless @messages.empty? return false unless @operations_in_progress.value.zero? @status.disconnecting! @monitor.instrument('producer.disconnecting', producer_id: id) @monitor.instrument('producer.disconnected', producer_id: id) do # Close the client @client.close @client = nil # Reset connection status but keep producer configured @status.disconnected! end true end end end end |
#disconnectable? ⇒ Boolean
This is a best effort method. The proper checks happen also when disconnecting behind all the needed mutexes
Is the producer in a state from which we can disconnect
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# File 'lib/waterdrop/producer.rb', line 257 def disconnectable? return false unless @client return false unless @status.connected? return false unless @messages.empty? return false if @transaction_mutex.locked? return false if @operating_mutex.locked? true end |
#idempotent? ⇒ Boolean
Returns true if current producer is idempotent.
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# File 'lib/waterdrop/producer.rb', line 185 def idempotent? # Every transactional producer is idempotent by default always return true if transactional? return @idempotent if instance_variable_defined?(:'@idempotent') @idempotent = config.kafka.to_h.fetch(:'enable.idempotence', false) end |
#inspect ⇒ String
Returns mutex-safe inspect details.
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# File 'lib/waterdrop/producer.rb', line 350 def inspect # Basic info that's always safe to access parts = [] parts << "id=#{@id.inspect}" parts << "status=#{@status}" if @status # Try to get buffer info safely if @buffer_mutex.try_lock begin parts << "buffer_size=#{@messages.size}" ensure @buffer_mutex.unlock end else parts << 'buffer_size=busy' end # Check if client is connected without triggering connection parts << if @status.connected? 'connected=true' else 'connected=false' end parts << "operations=#{@operations_in_progress.value}" parts << 'in_transaction=true' if @transaction_mutex.locked? "#<#{self.class.name}:#{format('%#x', object_id)} #{parts.join(' ')}>" end |
#middleware ⇒ WaterDrop::Producer::Middleware
Returns and caches the middleware object that may be used
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# File 'lib/waterdrop/producer.rb', line 195 def middleware @middleware ||= config.middleware end |
#partition_count(topic) ⇒ Integer
It uses the underlying rdkafka-ruby
partition count fetch and cache.
Fetches and caches the partition count of a topic
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# File 'lib/waterdrop/producer.rb', line 148 def partition_count(topic) client.partition_count(topic.to_s) end |
#purge ⇒ Object
This is an operation that can cause data loss. Keep that in mind. It will not only purge the internal WaterDrop buffer but will also purge the librdkafka queue as well as will cancel any outgoing messages dispatches.
Purges data from both the buffer queue as well as the librdkafka queue.
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# File 'lib/waterdrop/producer.rb', line 157 def purge @monitor.instrument('buffer.purged', producer_id: id) do @buffer_mutex.synchronize do @messages = [] end # We should not purge if there is no client initialized # It may not be initialized if we created a new producer that never connected to kafka, # we used buffer and purged. In cases like this client won't exist @connecting_mutex.synchronize do @client&.purge end end end |
#setup(&block) ⇒ Object
Sets up the whole configuration and initializes all that is needed
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# File 'lib/waterdrop/producer.rb', line 70 def setup(&block) raise Errors::ProducerAlreadyConfiguredError, id unless @status.initial? @config = Config .new .setup(&block) .config @id = @config.id @monitor = @config.monitor @contract = Contracts::Message.new(max_payload_size: @config.max_payload_size) @default_variant = Variant.new(self, default: true) return @status.configured! if @config.idle_disconnect_timeout.zero? # Setup idle disconnect listener if configured so we preserve tcp connections on rarely # used producers disconnector = Instrumentation::IdleDisconnectorListener.new( self, disconnect_timeout: @config.idle_disconnect_timeout ) @monitor.subscribe(disconnector) @status.configured! end |
#with(**args) ⇒ WaterDrop::Producer::Variant Also known as: variant
Builds the variant alteration and returns it.
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# File 'lib/waterdrop/producer.rb', line 176 def with(**args) ensure_active! Variant.new(self, **args) end |