feat: Add support for receiving gzip event payloads

config/config.go

@@ -184,11 +184,12 @@ type OfflineModeConfig struct {
 // variables, individual fields are not documented here; instead, see the `README.md` section on
 // configuration.
 type EventsConfig struct {
-	EventsURI     ct.OptURLAbsolute        `conf:"EVENTS_HOST"`
-	SendEvents    bool                     `conf:"USE_EVENTS"`
-	FlushInterval ct.OptDuration           `conf:"EVENTS_FLUSH_INTERVAL"`
-	Capacity      ct.OptIntGreaterThanZero `conf:"EVENTS_CAPACITY"`
-	InlineUsers   bool                     `conf:"EVENTS_INLINE_USERS"`
+	EventsURI             ct.OptURLAbsolute        `conf:"EVENTS_HOST"`
+	SendEvents            bool                     `conf:"USE_EVENTS"`
+	FlushInterval         ct.OptDuration           `conf:"EVENTS_FLUSH_INTERVAL"`
+	Capacity              ct.OptIntGreaterThanZero `conf:"EVENTS_CAPACITY"`
+	InlineUsers           bool                     `conf:"EVENTS_INLINE_USERS"`
+	MaxInboundPayloadSize ct.OptBase2Bytes         `conf:"EVENTS_MAX_INBOUND_PAYLOAD_SIZE"`
 }
 
 // RedisConfig configures the optional Redis integration.

config/config_validation.go

@@ -16,6 +16,7 @@ var (
 	errFileDataWithAutoConf            = errors.New("cannot specify both auto-configuration key and file data source")
 	errOfflineModePropertiesWithNoFile = errors.New("must specify offline mode filename if other offline mode properties are set")
 	errOfflineModeWithEnvironments     = errors.New("cannot configure specific environments if offline mode is enabled")
+	errMaxInboundPayloadSize           = errors.New("max inbound payload size must be greater than zero")
 	errAutoConfWithoutDBDisambig       = errors.New(`when using auto-configuration with database storage, database prefix (or,` +
 		` if using DynamoDB, table name) must be specified and must contain "` + AutoConfigEnvironmentIDPlaceholder + `"`)
 	errRedisURLWithHostAndPort                 = errors.New("please specify Redis URL or host/port, but not both")
@@ -80,6 +81,7 @@ func ValidateConfig(c *Config, loggers ldlog.Loggers) error {
 	validateConfigFilters(&result, c)
 	validateOfflineMode(&result, c)
 	validateCredentialCleanupInterval(&result, c)
+	validateMaxInboundPayloadSize(&result, c)
 
 	return result.GetError()
 }
@@ -206,6 +208,16 @@ func validateCredentialCleanupInterval(result *ct.ValidationResult, c *Config) {
 		}
 	}
 }
+
+func validateMaxInboundPayloadSize(result *ct.ValidationResult, c *Config) {
+	if c.Events.MaxInboundPayloadSize.IsDefined() {
+		size := c.Events.MaxInboundPayloadSize.GetOrElse(0)
+		if size <= 0 {
+			result.AddError(nil, errMaxInboundPayloadSize)
+		}
+	}
+}
+
 func validateConfigDatabases(result *ct.ValidationResult, c *Config, loggers ldlog.Loggers) {
 	normalizeRedisConfig(result, c)
 

config/test_data_configs_valid_test.go

@@ -65,6 +65,9 @@ func makeValidConfigs() []testDataValidConfig {
 		makeValidConfigExplicitOldDefaultBaseURI(),
 		makeValidConfigAutoConfig(),
 		makeValidConfigAutoConfigWithDatabase(),
+		makeValidConfigMaxInboundPayloadSize("50KiB"),
+		makeValidConfigMaxInboundPayloadSize("7MiB"),
+		makeValidConfigMaxInboundPayloadSize("10GiB"),
 		makeValidConfigOfflineModeMinimal(),
 		makeValidConfigOfflineModeWithMonitoringInterval("100ms"),
 		makeValidConfigOfflineModeWithMonitoringInterval("1s"),
@@ -118,11 +121,12 @@ func makeValidConfigAllBaseProperties() testDataValidConfig {
 			ExpiredCredentialCleanupInterval: ct.NewOptDuration(1 * time.Minute),
 		}
 		c.Events = EventsConfig{
-			SendEvents:    true,
-			EventsURI:     newOptURLAbsoluteMustBeValid("http://events"),
-			FlushInterval: ct.NewOptDuration(120 * time.Second),
-			Capacity:      mustOptIntGreaterThanZero(500),
-			InlineUsers:   true,
+			SendEvents:            true,
+			EventsURI:             newOptURLAbsoluteMustBeValid("http://events"),
+			FlushInterval:         ct.NewOptDuration(120 * time.Second),
+			Capacity:              mustOptIntGreaterThanZero(500),
+			InlineUsers:           true,
+			MaxInboundPayloadSize: ct.OptBase2Bytes{},
 		}
 		c.Environment = map[string]*EnvConfig{
 			"earth": {
@@ -356,6 +360,25 @@ FileDataSource = my-file-path
 	return c
 }
 
+func makeValidConfigMaxInboundPayloadSize(size string) testDataValidConfig {
+	bytes, err := ct.NewOptBase2BytesFromString(size)
+	if err != nil {
+		panic(err)
+	}
+	c := testDataValidConfig{name: "file data properties"}
+	c.makeConfig = func(c *Config) {
+		c.Events.MaxInboundPayloadSize = bytes
+	}
+	c.envVars = map[string]string{
+		"EVENTS_MAX_INBOUND_PAYLOAD_SIZE": size,
+	}
+	c.fileContent = `
+[Events]
+MaxInboundPayloadSize = ` + size
+
+	return c
+}
+
 func MustOptDurationFromString(duration string) ct.OptDuration {
 	opt, err := ct.NewOptDurationFromString(duration)
 	if err != nil {

docs/configuration.md

@@ -114,15 +114,17 @@ Note that the last three properties have the same meanings and the same environm
 
 To learn more, read [Forwarding events](./events.md).
 
-| Property in file | Environment var         |   Type   | Default | Description                                                                                                                                                                                                               |
-|------------------|-------------------------|:--------:|:--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| `sendEvents`     | `USE_EVENTS`            | Boolean  | `false` | When enabled, the Relay Proxy will send analytic events it receives to LaunchDarkly, unless offline mode is enabled.                                                                                                     |
-| `eventsUri`      | `EVENTS_HOST`           |   URI    | _(7)_   | URI for the LaunchDarkly events service                                                                                                                                                                                   |
-| `flushInterval`  | `EVENTS_FLUSH_INTERVAL` | Duration | `5s`    | Controls how long the SDK buffers events before sending them back to our server. If your server generates many events per second, we suggest decreasing the flush interval and/or increasing capacity to meet your needs. |
-| `capacity`       | `EVENTS_CAPACITY`       |  Number  | `1000`  | Maximum number of events to accumulate for each flush interval.                                                                                                                                                           |
-| `inlineUsers`    | `EVENTS_INLINE_USERS`   | Boolean  | `false` | When enabled, individual events (if full event tracking is enabled for the feature flag) will contain all non-private user attributes.                                                                                    |
+| Property in file              | Environment var                      |   Type   | Default | Description                                                                                                                                                                                                               |
+|-------------------------------|--------------------------------------|:--------:|:--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `sendEvents`                  | `USE_EVENTS`                         | Boolean  | `false` | When enabled, the Relay Proxy will send analytic events it receives to LaunchDarkly, unless offline mode is enabled.                                                                                                      |
+| `eventsUri`                   | `EVENTS_HOST`                        |   URI    | _(7)_   | URI for the LaunchDarkly events service                                                                                                                                                                                   |
+| `flushInterval`               | `EVENTS_FLUSH_INTERVAL`              | Duration | `5s`    | Controls how long the SDK buffers events before sending them back to our server. If your server generates many events per second, we suggest decreasing the flush interval and/or increasing capacity to meet your needs. |
+| `capacity`                    | `EVENTS_CAPACITY`                    |  Number  | `1000`  | Maximum number of events to accumulate for each flush interval.                                                                                                                                                           |
+| `inlineUsers`                 | `EVENTS_INLINE_USERS`                | Boolean  | `false` | When enabled, individual events (if full event tracking is enabled for the feature flag) will contain all non-private user attributes.                                                                                    |
+| `maxInboundPayloadSize`       | `EVENTS_MAX_INBOUND_PAYLOAD_SIZE`    | Unit     | _(8)_   | Maximum size of an event payload the Relay Proxy will accept from an SDK.                                                                                                                                                 |
 
 _(7)_ See note _(1)_ above. The default value for `eventsUri` is `https://events.launchdarkly.com`.
+_(8)_ The `maxInboundPayloadSize` setting is used to limit the size of the payload that the Relay Proxy will accept from an SDK. This is an optional safety feature to prevent the Relay Proxy from being overwhelmed by a very large payload. The default value is `0B` which provides no restriction on the payload size. The value should be a number followed by a unit: `B` for bytes, `KiB` for kibibytes, `MiB` for mebibytes, `GiB` for gibibytes, `TiB` for tebibytes, `PiB` for pebibytes, or `EiB` for exbibytes. For example, `100MiB` is 100 mebibytes.
 
 
 ### File section: `[Environment "NAME"]`

go.mod

@@ -1,6 +1,6 @@
 module github.com/launchdarkly/ld-relay/v8
 
-go 1.20
+go 1.21
 
 require (
 	contrib.go.opencensus.io/exporter/prometheus v0.4.2
@@ -12,7 +12,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/dynamodb v1.27.0
 	github.com/cyphar/filepath-securejoin v0.2.4
 	github.com/fatih/color v1.15.0 // indirect
-	github.com/fsnotify/fsnotify v1.7.0
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/go-redis/redis/v8 v8.11.5
 	github.com/gomodule/redigo v1.8.9
 	github.com/google/uuid v1.5.0 // indirect
@@ -25,15 +25,15 @@ require (
 	github.com/hashicorp/golang-lru v1.0.2 // indirect
 	github.com/kardianos/minwinsvc v1.0.2
 	github.com/launchdarkly/eventsource v1.7.1
-	github.com/launchdarkly/go-configtypes v1.1.0
+	github.com/launchdarkly/go-configtypes v1.2.0
 	github.com/launchdarkly/go-jsonstream/v3 v3.0.0
 	github.com/launchdarkly/go-sdk-common/v3 v3.1.0
-	github.com/launchdarkly/go-sdk-events/v3 v3.2.0
+	github.com/launchdarkly/go-sdk-events/v3 v3.4.0
 	github.com/launchdarkly/go-server-sdk-consul/v3 v3.0.0
 	github.com/launchdarkly/go-server-sdk-dynamodb/v4 v4.0.0
 	github.com/launchdarkly/go-server-sdk-evaluation/v3 v3.0.0
 	github.com/launchdarkly/go-server-sdk-redis-redigo/v3 v3.0.0
-	github.com/launchdarkly/go-server-sdk/v7 v7.1.0
+	github.com/launchdarkly/go-server-sdk/v7 v7.6.0
 	github.com/launchdarkly/go-test-helpers/v3 v3.0.2
 	github.com/launchdarkly/opencensus-go-exporter-stackdriver v0.14.2
 	github.com/pborman/uuid v1.2.1
@@ -59,7 +59,10 @@ require (
 	golang.org/x/exp v0.0.0-20231206192017-f3f8817b8deb
 )
 
-require github.com/launchdarkly/api-client-go/v13 v13.0.1-0.20230420175109-f5469391a13e
+require (
+	github.com/alecthomas/units v0.0.0-20231202071711-9a357b53e9c9
+	github.com/launchdarkly/api-client-go/v13 v13.0.1-0.20230420175109-f5469391a13e
+)
 
 require (
 	cloud.google.com/go/compute v1.23.3 // indirect
@@ -123,8 +126,6 @@ require (
 	google.golang.org/grpc v1.59.0 // indirect
 	google.golang.org/protobuf v1.33.0 // indirect
 	gopkg.in/DataDog/dd-trace-go.v1 v1.56.1 // indirect
-	gopkg.in/launchdarkly/go-jsonstream.v1 v1.0.1 // indirect
-	gopkg.in/launchdarkly/go-sdk-common.v2 v2.5.1 // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect