Support Snappy and Zstd for confighttp.go (#4441)

* feat: add snappy and zstd into confighttp

* fix: format the code

* fix: refactored. tests wip

* feat: add tests

* fix: fmt and lint

* fix: modified readme, removed decompression support, and removed compression from otlp

* fix: add compression on otlphttpexporter/readme

* chore: add changelog

* fix: applied changes from code review

* fix: comments and changelog

* fix: applied changes based on the code review

* fix: changed commend on changelog

* fix: changed map to switch case

* fix: move CompressionType to middleware to remove duplicated value

* fix: implement UnmarshalText for CompressionType

* fix: lint error

* fix: remove recommandation for compression type from readme

* chore: changelog

CHANGELOG.md

@@ -4,6 +4,8 @@
 
 ## 💡 Enhancements 💡
 
+- `confighttp`: add client-side compression support. (#4441)
+  - Each exporter should remove `compression` field if they have and should use `confighttp.HTTPClientSettings`
 -  Allow more zap logger configs: `disable_caller`, `disable_stacktrace`, `output_paths`, `error_output_paths`, `initial_fields` (#1048)
 - `configauth`: add ServerAuthenticator interfaces for HTTP receivers. (#4506)
 

config/confighttp/README.md

@@ -20,6 +20,9 @@ README](../configtls/README.md).
 - [`read_buffer_size`](https://golang.org/pkg/net/http/#Transport)
 - [`timeout`](https://golang.org/pkg/net/http/#Client)
 - [`write_buffer_size`](https://golang.org/pkg/net/http/#Transport)
+- `compression`: Compression type to use among `gzip`, `zstd`, `snappy`, `zlib`, and `deflate`.
+  - look at the documentation for the server-side of the communication.
+  - `none` will be treated as uncompressed, and any other inputs will cause an error.
 - [`max_idle_conns`](https://golang.org/pkg/net/http/#Transport)
 - [`max_idle_conns_per_host`](https://golang.org/pkg/net/http/#Transport)
 - [`max_conns_per_host`](https://golang.org/pkg/net/http/#Transport)
@@ -38,6 +41,7 @@ exporter:
     headers:
       test1: "value1"
       "test 2": "value 2"
+    compression: zstd
 ```
 
 ## Server Configuration

config/confighttp/confighttp.go

@@ -59,6 +59,9 @@ type HTTPClientSettings struct {
 	// Auth configuration for outgoing HTTP calls.
 	Auth *configauth.Authentication `mapstructure:"auth,omitempty"`
 
+	// The compression key for supported compression types within collector.
+	Compression middleware.CompressionType `mapstructure:"compression"`
+
 	// MaxIdleConns is used to set a limit to the maximum idle HTTP connections the client can keep open.
 	// There's an already set value, and we want to override it only if an explicit value provided
 	MaxIdleConns *int `mapstructure:"max_idle_conns"`
@@ -133,6 +136,12 @@ func (hcs *HTTPClientSettings) ToClient(ext map[config.ComponentID]component.Ext
 		}
 	}
 
+	// Compress the body using specified compression methods if non-empty string is provided.
+	// Supporting gzip, zlib, deflate, snappy, and zstd; none is treated as uncompressed.
+	if hcs.Compression != middleware.CompressionEmpty && hcs.Compression != middleware.CompressionNone {
+		clientTransport = middleware.NewCompressRoundTripper(clientTransport, hcs.Compression)
+	}
+
 	if hcs.Auth != nil {
 		if ext == nil {
 			return nil, fmt.Errorf("extensions configuration not found")

config/confighttp/confighttp_test.go

@@ -36,6 +36,7 @@ import (
 	"go.opentelemetry.io/collector/config"
 	"go.opentelemetry.io/collector/config/configauth"
 	"go.opentelemetry.io/collector/config/configtls"
+	"go.opentelemetry.io/collector/internal/middleware"
 )
 
 type customRoundTripper struct {
@@ -74,6 +75,43 @@ func TestAllHTTPClientSettings(t *testing.T) {
 				MaxConnsPerHost:     &maxConnsPerHost,
 				IdleConnTimeout:     &idleConnTimeout,
 				CustomRoundTripper:  func(next http.RoundTripper) (http.RoundTripper, error) { return next, nil },
+				Compression:         "",
+			},
+			shouldError: false,
+		},
+		{
+			name: "all_valid_settings_with_none_compression",
+			settings: HTTPClientSettings{
+				Endpoint: "localhost:1234",
+				TLSSetting: configtls.TLSClientSetting{
+					Insecure: false,
+				},
+				ReadBufferSize:      1024,
+				WriteBufferSize:     512,
+				MaxIdleConns:        &maxIdleConns,
+				MaxIdleConnsPerHost: &maxIdleConnsPerHost,
+				MaxConnsPerHost:     &maxConnsPerHost,
+				IdleConnTimeout:     &idleConnTimeout,
+				CustomRoundTripper:  func(next http.RoundTripper) (http.RoundTripper, error) { return next, nil },
+				Compression:         "none",
+			},
+			shouldError: false,
+		},
+		{
+			name: "all_valid_settings_with_gzip_compression",
+			settings: HTTPClientSettings{
+				Endpoint: "localhost:1234",
+				TLSSetting: configtls.TLSClientSetting{
+					Insecure: false,
+				},
+				ReadBufferSize:      1024,
+				WriteBufferSize:     512,
+				MaxIdleConns:        &maxIdleConns,
+				MaxIdleConnsPerHost: &maxIdleConnsPerHost,
+				MaxConnsPerHost:     &maxConnsPerHost,
+				IdleConnTimeout:     &idleConnTimeout,
+				CustomRoundTripper:  func(next http.RoundTripper) (http.RoundTripper, error) { return next, nil },
+				Compression:         "gzip",
 			},
 			shouldError: false,
 		},
@@ -100,14 +138,17 @@ func TestAllHTTPClientSettings(t *testing.T) {
 				return
 			}
 			assert.NoError(t, err)
-			transport := client.Transport.(*http.Transport)
-			assert.EqualValues(t, 1024, transport.ReadBufferSize)
-			assert.EqualValues(t, 512, transport.WriteBufferSize)
-			assert.EqualValues(t, 50, transport.MaxIdleConns)
-			assert.EqualValues(t, 40, transport.MaxIdleConnsPerHost)
-			assert.EqualValues(t, 45, transport.MaxConnsPerHost)
-			assert.EqualValues(t, 30*time.Second, transport.IdleConnTimeout)
-
+			switch transport := client.Transport.(type) {
+			case *http.Transport:
+				assert.EqualValues(t, 1024, transport.ReadBufferSize)
+				assert.EqualValues(t, 512, transport.WriteBufferSize)
+				assert.EqualValues(t, 50, transport.MaxIdleConns)
+				assert.EqualValues(t, 40, transport.MaxIdleConnsPerHost)
+				assert.EqualValues(t, 45, transport.MaxConnsPerHost)
+				assert.EqualValues(t, 30*time.Second, transport.IdleConnTimeout)
+			case *middleware.CompressRoundTripper:
+				assert.EqualValues(t, "gzip", transport.CompressionType())
+			}
 		})
 	}
 }

exporter/otlphttpexporter/README.md

@@ -30,14 +30,10 @@ The following settings can be optionally configured:
   - `ca_file` path to the CA cert. For a client this verifies the server certificate. Should only be used if `insecure` is set to false.
   - `cert_file` path to the TLS cert to use for TLS required connections. Should only be used if `insecure` is set to false.
   - `key_file` path to the TLS key to use for TLS required connections. Should only be used if `insecure` is set to false.
-
-- `compression` (default = none): Compression type to use (only gzip is supported today)
-
 - `timeout` (default = 30s): HTTP request time limit. For details see https://golang.org/pkg/net/http/#Client
 - `read_buffer_size` (default = 0): ReadBufferSize for HTTP client.
 - `write_buffer_size` (default = 512 * 1024): WriteBufferSize for HTTP client.
 
-
 Example:
 
 ```yaml

exporter/otlphttpexporter/config.go

@@ -35,10 +35,6 @@ type Config struct {
 
 	// The URL to send logs to. If omitted the Endpoint + "/v1/logs" will be used.
 	LogsEndpoint string `mapstructure:"logs_endpoint"`
-
-	// The compression key for supported compression types within
-	// collector. Currently the only supported mode is `gzip`.
-	Compression string `mapstructure:"compression"`
 }
 
 var _ config.Exporter = (*Config)(nil)

exporter/otlphttpexporter/config_test.go

@@ -77,7 +77,7 @@ func TestLoadConfig(t *testing.T) {
 				ReadBufferSize:  123,
 				WriteBufferSize: 345,
 				Timeout:         time.Second * 10,
+				Compression:     "gzip",
 			},
-			Compression: "gzip",
 		})
 }

exporter/otlphttpexporter/otlp.go

@@ -25,7 +25,6 @@ import (
 	"net/url"
 	"runtime"
 	"strconv"
-	"strings"
 	"time"
 
 	"go.uber.org/zap"
@@ -34,10 +33,8 @@ import (
 
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/config"
-	"go.opentelemetry.io/collector/config/configgrpc"
 	"go.opentelemetry.io/collector/consumer/consumererror"
 	"go.opentelemetry.io/collector/exporter/exporterhelper"
-	"go.opentelemetry.io/collector/internal/middleware"
 	"go.opentelemetry.io/collector/model/otlpgrpc"
 	"go.opentelemetry.io/collector/model/pdata"
 )
@@ -89,14 +86,6 @@ func (e *exporter) start(_ context.Context, host component.Host) error {
 	if err != nil {
 		return err
 	}
-
-	if e.config.Compression != "" {
-		if strings.ToLower(e.config.Compression) == configgrpc.CompressionGzip {
-			client.Transport = middleware.NewCompressRoundTripper(client.Transport)
-		} else {
-			return fmt.Errorf("unsupported compression type %q", e.config.Compression)
-		}
-	}
 	e.client = client
 	return nil
 }

exporter/otlphttpexporter/otlp_test.go

@@ -134,63 +134,6 @@ func TestTraceRoundTrip(t *testing.T) {
 	}
 }
 
-func TestCompressionOptions(t *testing.T) {
-	addr := testutil.GetAvailableLocalAddress(t)
-
-	tests := []struct {
-		name        string
-		baseURL     string
-		compression string
-		err         bool
-	}{
-		{
-			name:        "no compression",
-			baseURL:     fmt.Sprintf("http://%s", addr),
-			compression: "",
-		},
-		{
-			name:        "gzip",
-			baseURL:     fmt.Sprintf("http://%s", addr),
-			compression: "gzip",
-		},
-		{
-			name:        "incorrect compression",
-			baseURL:     fmt.Sprintf("http://%s", addr),
-			compression: "gzip2",
-			err:         true,
-		},
-	}
-
-	for _, test := range tests {
-		t.Run(test.name, func(t *testing.T) {
-			sink := new(consumertest.TracesSink)
-			startTracesReceiver(t, addr, sink)
-
-			factory := NewFactory()
-			cfg := createExporterConfig(test.baseURL, factory.CreateDefaultConfig())
-			cfg.Compression = test.compression
-			exp, _ := factory.CreateTracesExporter(context.Background(), componenttest.NewNopExporterCreateSettings(), cfg)
-			err := exp.Start(context.Background(), componenttest.NewNopHost())
-			t.Cleanup(func() {
-				require.NoError(t, exp.Shutdown(context.Background()))
-			})
-			if test.err {
-				require.Error(t, err)
-				return
-			}
-
-			td := testdata.GenerateTracesOneSpan()
-			assert.NoError(t, exp.ConsumeTraces(context.Background(), td))
-			require.Eventually(t, func() bool {
-				return sink.SpanCount() > 0
-			}, 1*time.Second, 10*time.Millisecond)
-			allTraces := sink.AllTraces()
-			require.Len(t, allTraces, 1)
-			assert.EqualValues(t, td, allTraces[0])
-		})
-	}
-}
-
 func TestMetricsError(t *testing.T) {
 	addr := testutil.GetAvailableLocalAddress(t)
 

go.mod

@@ -6,8 +6,10 @@ require (
 	contrib.go.opencensus.io/exporter/prometheus v0.4.0
 	github.com/cenkalti/backoff/v4 v4.1.2
 	github.com/gogo/protobuf v1.3.2
+	github.com/golang/snappy v0.0.4
 	github.com/google/uuid v1.3.0
 	github.com/gorilla/mux v1.8.0
+	github.com/klauspost/compress v1.13.6
 	github.com/knadh/koanf v1.3.3
 	github.com/magiconair/properties v1.8.5
 	github.com/mitchellh/mapstructure v1.4.3
@@ -50,9 +52,7 @@ require (
 	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
-	github.com/golang/snappy v0.0.4 // indirect
 	github.com/inconshreveable/mousetrap v1.0.0 // indirect
-	github.com/klauspost/compress v1.13.6 // indirect
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect