github.com/Jeffail/benthos/v3@v3.65.0/lib/buffer/memory.go (about) 1 package buffer 2 3 import ( 4 "fmt" 5 6 "github.com/Jeffail/benthos/v3/internal/docs" 7 "github.com/Jeffail/benthos/v3/lib/buffer/parallel" 8 "github.com/Jeffail/benthos/v3/lib/log" 9 "github.com/Jeffail/benthos/v3/lib/message/batch" 10 "github.com/Jeffail/benthos/v3/lib/metrics" 11 "github.com/Jeffail/benthos/v3/lib/types" 12 ) 13 14 //------------------------------------------------------------------------------ 15 16 func init() { 17 Constructors[TypeMemory] = TypeSpec{ 18 constructor: NewMemory, 19 Summary: ` 20 Stores consumed messages in memory and acknowledges them at the input level. 21 During shutdown Benthos will make a best attempt at flushing all remaining 22 messages before exiting cleanly.`, 23 Description: ` 24 This buffer is appropriate when consuming messages from inputs that do not 25 gracefully handle back pressure and where delivery guarantees aren't critical. 26 27 This buffer has a configurable limit, where consumption will be stopped with 28 back pressure upstream if the total size of messages in the buffer reaches this 29 amount. Since this calculation is only an estimate, and the real size of 30 messages in RAM is always higher, it is recommended to set the limit 31 significantly below the amount of RAM available. 32 33 ## Delivery Guarantees 34 35 This buffer intentionally weakens the delivery guarantees of the pipeline and 36 therefore should never be used in places where data loss is unacceptable. 37 38 ## Batching 39 40 It is possible to batch up messages sent from this buffer using a 41 [batch policy](/docs/configuration/batching#batch-policy).`, 42 FieldSpecs: docs.FieldSpecs{ 43 docs.FieldCommon("limit", "The maximum buffer size (in bytes) to allow before applying backpressure upstream."), 44 docs.FieldCommon("batch_policy", "Optionally configure a policy to flush buffered messages in batches.").WithChildren( 45 append(docs.FieldSpecs{ 46 docs.FieldCommon("enabled", "Whether to batch messages as they are flushed."), 47 }, batch.FieldSpec().Children...)..., 48 ), 49 }, 50 } 51 } 52 53 //------------------------------------------------------------------------------ 54 55 // EnabledBatchPolicyConfig is a batch.PolicyConfig with an enable field. 56 type EnabledBatchPolicyConfig struct { 57 Enabled bool `json:"enabled" yaml:"enabled"` 58 batch.PolicyConfig `json:",inline" yaml:",inline"` 59 } 60 61 // MemoryConfig is config values for a purely memory based ring buffer type. 62 type MemoryConfig struct { 63 Limit int `json:"limit" yaml:"limit"` 64 BatchPolicy EnabledBatchPolicyConfig `json:"batch_policy" yaml:"batch_policy"` 65 } 66 67 // NewMemoryConfig creates a new MemoryConfig with default values. 68 func NewMemoryConfig() MemoryConfig { 69 return MemoryConfig{ 70 Limit: 1024 * 1024 * 500, // 500MB 71 BatchPolicy: EnabledBatchPolicyConfig{ 72 Enabled: false, 73 PolicyConfig: batch.NewPolicyConfig(), 74 }, 75 } 76 } 77 78 //------------------------------------------------------------------------------ 79 80 // NewMemory creates a buffer held in memory. 81 func NewMemory(config Config, mgr types.Manager, log log.Modular, stats metrics.Type) (Type, error) { 82 wrap := NewParallelWrapper(config, parallel.NewMemory(config.Memory.Limit), log, stats) 83 if !config.Memory.BatchPolicy.Enabled { 84 return wrap, nil 85 } 86 pol, err := batch.NewPolicy(config.Memory.BatchPolicy.PolicyConfig, mgr, log, stats) 87 if err != nil { 88 return nil, fmt.Errorf("batch policy config error: %v", err) 89 } 90 return NewParallelBatcher(pol, wrap, log, stats), nil 91 } 92 93 //------------------------------------------------------------------------------