Merge branch 'build-chunks-on-object-storage' into 'master'

Allow to store BuildTraceChunks on Object Storage

Closes #45712

See merge request gitlab-org/gitlab-ce!19515

4 files changed, 203 insertions, 85 deletions

diff --git a/app/models/ci/build_trace_chunk.rb b/app/models/ci/build_trace_chunk.rb
index 4856f10846c..b442de34061 100644
--- a/app/models/ci/build_trace_chunk.rb
+++ b/app/models/ci/build_trace_chunk.rb
@@ -1,54 +1,58 @@
 module Ci
   class BuildTraceChunk < ActiveRecord::Base
     include FastDestroyAll
+    include ::Gitlab::ExclusiveLeaseHelpers
     extend Gitlab::Ci::Model
 
     belongs_to :build, class_name: "Ci::Build", foreign_key: :build_id
 
     default_value_for :data_store, :redis
 
-    WriteError = Class.new(StandardError)
-
     CHUNK_SIZE = 128.kilobytes
-    CHUNK_REDIS_TTL = 1.week
     WRITE_LOCK_RETRY = 10
     WRITE_LOCK_SLEEP = 0.01.seconds
     WRITE_LOCK_TTL = 1.minute
 
+    # Note: The ordering of this enum is related to the precedence of persist store.
+    # The bottom item takes the higest precedence, and the top item takes the lowest precedence.
     enum data_store: {
       redis: 1,
-      db: 2
+      database: 2,
+      fog: 3
     }
 
     class << self
-      def redis_data_key(build_id, chunk_index)
-        "gitlab:ci:trace:#{build_id}:chunks:#{chunk_index}"
+      def all_stores
+        @all_stores ||= self.data_stores.keys
       end
 
-      def redis_data_keys
-        redis.pluck(:build_id, :chunk_index).map do |data|
-          redis_data_key(data.first, data.second)
-        end
+      def persistable_store
+        # get first available store from the back of the list
+        all_stores.reverse.find { |store| get_store_class(store).available? }
       end
 
-      def redis_delete_data(keys)
-        return if keys.empty?
-
-        Gitlab::Redis::SharedState.with do |redis|
-          redis.del(keys)
-        end
+      def get_store_class(store)
+        @stores ||= {}
+        @stores[store] ||= "Ci::BuildTraceChunks::#{store.capitalize}".constantize.new
       end
 
       ##
       # FastDestroyAll concerns
       def begin_fast_destroy
-        redis_data_keys
+        all_stores.each_with_object({}) do |store, result|
+          relation = public_send(store) # rubocop:disable GitlabSecurity/PublicSend
+          keys = get_store_class(store).keys(relation)
+
+          result[store] = keys if keys.present?
+        end
       end
 
       ##
       # FastDestroyAll concerns
       def finalize_fast_destroy(keys)
-        redis_delete_data(keys)
+        keys.each do |store, value|
+          get_store_class(store).delete_keys(value)
+        end
       end
     end
 
@@ -66,10 +70,15 @@ module Ci
     end
 
     def append(new_data, offset)
+      raise ArgumentError, 'New data is missing' unless new_data
       raise ArgumentError, 'Offset is out of range' if offset > size || offset < 0
       raise ArgumentError, 'Chunk size overflow' if CHUNK_SIZE < (offset + new_data.bytesize)
 
-      set_data(data.byteslice(0, offset) + new_data)
+      in_lock(*lock_params) do # Write opetation is atomic
+        unsafe_set_data!(data.byteslice(0, offset) + new_data)
+      end
+
+      schedule_to_persist if full?
     end
 
     def size
@@ -88,93 +97,63 @@ module Ci
       (start_offset...end_offset)
     end
 
-    def use_database!
-      in_lock do
-        break if db?
-        break unless size > 0
-
-        self.update!(raw_data: data, data_store: :db)
-        self.class.redis_delete_data([redis_data_key])
+    def persist_data!
+      in_lock(*lock_params) do # Write opetation is atomic
+        unsafe_persist_to!(self.class.persistable_store)
       end
     end
 
     private
 
-    def get_data
-      if redis?
-        redis_data
-      elsif db?
-        raw_data
-      else
-        raise 'Unsupported data store'
-      end&.force_encoding(Encoding::BINARY) # Redis/Database return UTF-8 string as default
-    end
-
-    def set_data(value)
-      raise ArgumentError, 'too much data' if value.bytesize > CHUNK_SIZE
-
-      in_lock do
-        if redis?
-          redis_set_data(value)
-        elsif db?
-          self.raw_data = value
-        else
-          raise 'Unsupported data store'
-        end
+    def unsafe_persist_to!(new_store)
+      return if data_store == new_store.to_s
+      raise ArgumentError, 'Can not persist empty data' unless size > 0
 
-        @data = value
+      old_store_class = self.class.get_store_class(data_store)
 
-        save! if changed?
+      get_data.tap do |the_data|
+        self.raw_data = nil
+        self.data_store = new_store
+        unsafe_set_data!(the_data)
       end
 
-      schedule_to_db if full?
-    end
-
-    def schedule_to_db
-      return if db?
-
-      Ci::BuildTraceChunkFlushWorker.perform_async(id)
+      old_store_class.delete_data(self)
     end
 
-    def full?
-      size == CHUNK_SIZE
+    def get_data
+      self.class.get_store_class(data_store).data(self)&.force_encoding(Encoding::BINARY) # Redis/Database return UTF-8 string as default
+    rescue Excon::Error::NotFound
+      # If the data store is :fog and the file does not exist in the object storage, this method returns nil.
     end
 
-    def redis_data
-      Gitlab::Redis::SharedState.with do |redis|
-        redis.get(redis_data_key)
-      end
-    end
+    def unsafe_set_data!(value)
+      raise ArgumentError, 'New data size exceeds chunk size' if value.bytesize > CHUNK_SIZE
 
-    def redis_set_data(data)
-      Gitlab::Redis::SharedState.with do |redis|
-        redis.set(redis_data_key, data, ex: CHUNK_REDIS_TTL)
-      end
-    end
+      self.class.get_store_class(data_store).set_data(self, value)
+      @data = value
 
-    def redis_data_key
-      self.class.redis_data_key(build_id, chunk_index)
+      save! if changed?
     end
 
-    def in_lock
-      write_lock_key = "trace_write:#{build_id}:chunks:#{chunk_index}"
+    def schedule_to_persist
+      return if data_persisted?
 
-      lease = Gitlab::ExclusiveLease.new(write_lock_key, timeout: WRITE_LOCK_TTL)
-      retry_count = 0
+      Ci::BuildTraceChunkFlushWorker.perform_async(id)
+    end
 
-      until uuid = lease.try_obtain
-        # Keep trying until we obtain the lease. To prevent hammering Redis too
-        # much we'll wait for a bit between retries.
-        sleep(WRITE_LOCK_SLEEP)
-        break if WRITE_LOCK_RETRY < (retry_count += 1)
-      end
+    def data_persisted?
+      !redis?
+    end
 
-      raise WriteError, 'Failed to obtain write lock' unless uuid
+    def full?
+      size == CHUNK_SIZE
+    end
 
-      self.reload if self.persisted?
-      return yield
-    ensure
-      Gitlab::ExclusiveLease.cancel(write_lock_key, uuid)
+    def lock_params
+      ["trace_write:#{build_id}:chunks:#{chunk_index}",
+       { ttl: WRITE_LOCK_TTL,
+         retries: WRITE_LOCK_RETRY,
+         sleep_sec: WRITE_LOCK_SLEEP }]
     end
   end
 end
diff --git a/app/models/ci/build_trace_chunks/database.rb b/app/models/ci/build_trace_chunks/database.rb
new file mode 100644
index 00000000000..3666d77c790
--- /dev/null
+++ b/app/models/ci/build_trace_chunks/database.rb
@@ -0,0 +1,29 @@
+module Ci
+  module BuildTraceChunks
+    class Database
+      def available?
+        true
+      end
+
+      def keys(relation)
+        []
+      end
+
+      def delete_keys(keys)
+        # no-op
+      end
+
+      def data(model)
+        model.raw_data
+      end
+
+      def set_data(model, data)
+        model.raw_data = data
+      end
+
+      def delete_data(model)
+        model.update_columns(raw_data: nil) unless model.raw_data.nil?
+      end
+    end
+  end
+end
diff --git a/app/models/ci/build_trace_chunks/fog.rb b/app/models/ci/build_trace_chunks/fog.rb
new file mode 100644
index 00000000000..7506c40a39d
--- /dev/null
+++ b/app/models/ci/build_trace_chunks/fog.rb
@@ -0,0 +1,59 @@
+module Ci
+  module BuildTraceChunks
+    class Fog
+      def available?
+        object_store.enabled
+      end
+
+      def data(model)
+        connection.get_object(bucket_name, key(model))[:body]
+      end
+
+      def set_data(model, data)
+        connection.put_object(bucket_name, key(model), data)
+      end
+
+      def delete_data(model)
+        delete_keys([[model.build_id, model.chunk_index]])
+      end
+
+      def keys(relation)
+        return [] unless available?
+
+        relation.pluck(:build_id, :chunk_index)
+      end
+
+      def delete_keys(keys)
+        keys.each do |key|
+          connection.delete_object(bucket_name, key_raw(*key))
+        end
+      end
+
+      private
+
+      def key(model)
+        key_raw(model.build_id, model.chunk_index)
+      end
+
+      def key_raw(build_id, chunk_index)
+        "tmp/builds/#{build_id.to_i}/chunks/#{chunk_index.to_i}.log"
+      end
+
+      def bucket_name
+        return unless available?
+
+        object_store.remote_directory
+      end
+
+      def connection
+        return unless available?
+
+        @connection ||= ::Fog::Storage.new(object_store.connection.to_hash.deep_symbolize_keys)
+      end
+
+      def object_store
+        Gitlab.config.artifacts.object_store
+      end
+    end
+  end
+end
diff --git a/app/models/ci/build_trace_chunks/redis.rb b/app/models/ci/build_trace_chunks/redis.rb
new file mode 100644
index 00000000000..fdb6065e2a0
--- /dev/null
+++ b/app/models/ci/build_trace_chunks/redis.rb
@@ -0,0 +1,51 @@
+module Ci
+  module BuildTraceChunks
+    class Redis
+      CHUNK_REDIS_TTL = 1.week
+
+      def available?
+        true
+      end
+
+      def data(model)
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.get(key(model))
+        end
+      end
+
+      def set_data(model, data)
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.set(key(model), data, ex: CHUNK_REDIS_TTL)
+        end
+      end
+
+      def delete_data(model)
+        delete_keys([[model.build_id, model.chunk_index]])
+      end
+
+      def keys(relation)
+        relation.pluck(:build_id, :chunk_index)
+      end
+
+      def delete_keys(keys)
+        return if keys.empty?
+
+        keys = keys.map { |key| key_raw(*key) }
+
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.del(keys)
+        end
+      end
+
+      private
+
+      def key(model)
+        key_raw(model.build_id, model.chunk_index)
+      end
+
+      def key_raw(build_id, chunk_index)
+        "gitlab:ci:trace:#{build_id.to_i}:chunks:#{chunk_index.to_i}"
+      end
+    end
+  end
+end