internal/envoy: configurable access log format

* Adds new configuration option that allows setting the format string for
  Envoy's text based access log.
* Adds support for Envoy's REQ_WITHOUT_QUERY command operator, which can
  be used to avoid writing query string to access log.

Signed-off-by: Tero Saarni <[email protected]>

cmd/contour/serve.go

@@ -296,6 +296,8 @@ func doServe(log logrus.FieldLogger, ctx *serveContext) error {
 		HTTPSAccessLog:                ctx.httpsAccessLog,
 		AccessLogType:                 ctx.Config.AccessLogFormat,
 		AccessLogFields:               ctx.Config.AccessLogFields,
+		AccessLogFormatString:         ctx.Config.AccessLogFormatString,
+		AccessLogFormatterExtensions:  ctx.Config.AccessLogFormatterExtensions(),
 		MinimumTLSVersion:             annotation.MinTLSVersion(ctx.Config.TLS.MinimumProtocolVersion, "1.2"),
 		CipherSuites:                  config.SanitizeCipherSuites(ctx.Config.TLS.CipherSuites),
 		RequestTimeout:                requestTimeout,

examples/contour/01-contour-config.yaml

@@ -54,6 +54,8 @@ data:
     ### Logging options
     # Default setting
     accesslog-format: envoy
+    # The default access log format is defined by Envoy but it can be customized by setting following variable.
+    # accesslog-format-string: "...\n"
     # To enable JSON logging in Envoy
     # accesslog-format: json
     # The default fields that will be logged are specified below.

examples/render/contour-gateway.yaml

@@ -90,6 +90,8 @@ data:
     ### Logging options
     # Default setting
     accesslog-format: envoy
+    # The default access log format is defined by Envoy but it can be customized by setting following variable.
+    # accesslog-format-string: "...\n"
     # To enable JSON logging in Envoy
     # accesslog-format: json
     # The default fields that will be logged are specified below.

examples/render/contour.yaml

@@ -88,6 +88,8 @@ data:
     ### Logging options
     # Default setting
     accesslog-format: envoy
+    # The default access log format is defined by Envoy but it can be customized by setting following variable.
+    # accesslog-format-string: "...\n"
     # To enable JSON logging in Envoy
     # accesslog-format: json
     # The default fields that will be logged are specified below.

go.mod

@@ -5,7 +5,7 @@ go 1.15
 require (
 	github.com/ahmetb/gen-crd-api-reference-docs v0.3.0
 	github.com/bombsimon/logrusr v1.0.0
-	github.com/envoyproxy/go-control-plane v0.9.9-0.20210111201334-f1f47757da33
+	github.com/envoyproxy/go-control-plane v0.9.10-0.20210614203518-782de910ff04
 	github.com/go-logr/logr v0.4.0
 	github.com/golang/protobuf v1.4.3
 	github.com/google/go-cmp v0.5.2
@@ -17,9 +17,9 @@ require (
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.15.0
 	github.com/sirupsen/logrus v1.7.0
-	github.com/stretchr/testify v1.6.1
+	github.com/stretchr/testify v1.7.0
 	google.golang.org/genproto v0.0.0-20201110150050-8816d57aaa9a
-	google.golang.org/grpc v1.27.1
+	google.golang.org/grpc v1.36.0
 	google.golang.org/protobuf v1.25.0
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
 	gopkg.in/yaml.v2 v2.4.0

go.sum

@@ -83,6 +83,7 @@ github.com/alecthomas/units v0.0.0-20190717042225-c3de453c63f4/go.mod h1:ybxpYRF
 github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d h1:UQZhZ2O0vMHr2cI+DC1Mbh0TJxzA3RcLoMsFw+aXw7E=
 github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d/go.mod h1:rBZYJk541a8SKzHPHnH3zbiI+7dagKZ0cgpgrD7Fyho=
 github.com/andreyvit/diff v0.0.0-20170406064948-c7f18ee00883/go.mod h1:rCTlJbsFo29Kk6CurOXKm700vrz8f0KW0JNfpkRJY/8=
+github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/apache/thrift v0.12.0/go.mod h1:cp2SuWMxlEZw2r+iP2GNCdIi4C1qmUzdZFSVb+bacwQ=
 github.com/apache/thrift v0.13.0/go.mod h1:cp2SuWMxlEZw2r+iP2GNCdIi4C1qmUzdZFSVb+bacwQ=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
@@ -121,8 +122,11 @@ github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMn
 github.com/clbanning/x2j v0.0.0-20191024224557-825249438eec/go.mod h1:jMjuTZXRI4dUb/I5gc9Hdhagfvm9+RyrPryS/auMzxE=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cloudflare/cloudflare-go v0.13.2/go.mod h1:27kfc1apuifUmJhp069y0+hwlKDg4bd8LWlu7oKeZvM=
+github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403 h1:cqQfy1jclcSy/FwLjemeg3SR1yaINm74aQyupQ0Bl8M=
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
+github.com/cncf/xds/go v0.0.0-20210312221358-fbca930ec8ed h1:OZmjad4L3H8ncOIR8rnb5MREYqG8ixi5+WbeUsquF0c=
+github.com/cncf/xds/go v0.0.0-20210312221358-fbca930ec8ed/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
 github.com/cockroachdb/datadriven v0.0.0-20190809214429-80d97fb3cbaa/go.mod h1:zn76sxSg3SzpJ0PPJaLDCu+Bu0Lg3sKTORVIj19EIF8=
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd/go.mod h1:sE/e/2PUdi/liOCUjSTXgM1o87ZssimdTWN964YiIeI=
 github.com/coreos/bbolt v1.3.2/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
@@ -169,8 +173,12 @@ github.com/emicklei/go-restful v2.9.5+incompatible/go.mod h1:otzb+WCGbkyDHkqmQmT
 github.com/envoyproxy/go-control-plane v0.6.9/go.mod h1:SBwIajubJHhxtWwsL9s8ss4safvEdbitLhGGK48rN6g=
 github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
+github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
+github.com/envoyproxy/go-control-plane v0.9.9-0.20201210154907-fd9021fe5dad/go.mod h1:cXg6YxExXjJnVBQHBLXeUAgxn2UodCpnH306RInaBQk=
 github.com/envoyproxy/go-control-plane v0.9.9-0.20210111201334-f1f47757da33 h1:U16cYLyGghDDNddBIk9+PwCIwkyqGnt+W29t8JmYfnk=
 github.com/envoyproxy/go-control-plane v0.9.9-0.20210111201334-f1f47757da33/go.mod h1:cXg6YxExXjJnVBQHBLXeUAgxn2UodCpnH306RInaBQk=
+github.com/envoyproxy/go-control-plane v0.9.10-0.20210614203518-782de910ff04 h1:Tf/fkJiR5CnKHqyr+qwRGhnimnWnM6J6tIfjUc9k3L0=
+github.com/envoyproxy/go-control-plane v0.9.10-0.20210614203518-782de910ff04/go.mod h1:+baROYa9cKpDyN21rZlsSq5zgBrZOrMTNu78Lm3fFJQ=
 github.com/envoyproxy/protoc-gen-validate v0.1.0 h1:EQciDnbrYxy13PgWoY8AqoxGiPrpgBZ1R8UNe3ddc+A=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/evanphx/json-patch v4.2.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
@@ -364,6 +372,7 @@ github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0 h1:Ovs26xHkKqVztRpIrF/92Bcuy
 github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0/go.mod h1:8NvIoxWQoOIhqOTXgfV/d3M/q6VIi02HzZEHgUlZvzk=
 github.com/grpc-ecosystem/grpc-gateway v1.9.0/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
 github.com/grpc-ecosystem/grpc-gateway v1.9.5/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
+github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/hashicorp/consul/api v1.1.0/go.mod h1:VmuI/Lkw1nC05EYQWNKwWGbkg+FbDBtguAZLlVdkD9Q=
 github.com/hashicorp/consul/api v1.3.0/go.mod h1:MmDNSzIMUjNpY/mQ398R4bk2FnqQLoPndWW5VkKPlCE=
 github.com/hashicorp/consul/sdk v0.1.1/go.mod h1:VKf9jXwCTEY1QZP2MOLRhb5i/I/ssyNV1vwHyQBF0x8=
@@ -608,6 +617,7 @@ github.com/prometheus/procfs v0.2.0/go.mod h1:lV6e/gmhEcM9IjHGsFOCxxuZ+z1YqCvr4O
 github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40TwIPHuXU=
 github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a/go.mod h1:bCqnVzQkZxMG4s8nGwiZ5l3QUCyqpo9Y+/ZMZ9VjZe4=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
+github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6LYCDYWNEvQ=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/russross/blackfriday v1.5.2 h1:HyvC0ARfnZBqnXwABFeSZHpKvJHJJfPz81GNueLj0oo=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
@@ -663,6 +673,8 @@ github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81P
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0/go.mod h1:N0PQaV/YGNqwC0u51sEeR/aUtSLEXKX9iv69rRypqCw=
 github.com/tidwall/pretty v1.0.0/go.mod h1:XNkn88O1ChpSDQmQeStsy+sBenx6DDtFZJxhVysOjyk=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20170815181823-89b8d40f7ca8/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
@@ -695,6 +707,7 @@ go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 go.opencensus.io v0.22.0/go.mod h1:+kGneAE2xo2IficOXnaByMWTGM9T73dGwxeWcUqIpI8=
 go.opencensus.io v0.22.2/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opencensus.io v0.22.3/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
+go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 go.uber.org/atomic v1.3.2/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.5.0/go.mod h1:sABNBOSYdrvTF6hTgEIbc7YasKWGhgEQZyfxyTvoXHQ=
@@ -1002,6 +1015,7 @@ google.golang.org/genproto v0.0.0-20200204135345-fa8e72b47b90/go.mod h1:GmwEX6Z4
 google.golang.org/genproto v0.0.0-20200212174721-66ed5ce911ce/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200224152610-e50cd9704f63/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200305110556-506484158171/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
+google.golang.org/genproto v0.0.0-20200513103714-09dca8ec2884/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
 google.golang.org/genproto v0.0.0-20201019141844-1ed22bb0c154/go.mod h1:FWY/as6DDZQgahTzZj3fqbO1CbirC29ZNUFHwi0/+no=
 google.golang.org/genproto v0.0.0-20201110150050-8816d57aaa9a h1:pOwg4OoaRYScjmR4LlLgdtnyoHYTSAVhhqe5uPdpII8=
@@ -1022,6 +1036,9 @@ google.golang.org/grpc v1.26.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.27.1 h1:zvIju4sqAGvwKspUQOhwnpcqSbzi7/H6QomNNjTL4sk=
 google.golang.org/grpc v1.27.1/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
+google.golang.org/grpc v1.33.1/go.mod h1:fr5YgcSWrqhRRxogOsw7RzIpsmvOZ6IcH4kBYTpR3n0=
+google.golang.org/grpc v1.36.0 h1:o1bcQ6imQMIOpdrO3SWf2z5RV72WbDwdXuK0MDlc8As=
+google.golang.org/grpc v1.36.0/go.mod h1:qjiiYl8FncCW8feJPdyg3v6XW24KsRHe+dy9BAGRRjU=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
@@ -1060,6 +1077,7 @@ gopkg.in/yaml.v2 v2.0.0-20170812160011-eb3733d160e7/go.mod h1:JAlM8MvJe8wmxCU4Bl
 gopkg.in/yaml.v2 v2.0.0/go.mod h1:JAlM8MvJe8wmxCU4Bli9HhUf9+ttbYbLASfIpnQbh74=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.5/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.7/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

internal/envoy/v3/accesslog.go

@@ -17,29 +17,47 @@ import (
 	envoy_accesslog_v3 "github.com/envoyproxy/go-control-plane/envoy/config/accesslog/v3"
 	envoy_config_core_v3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
 	envoy_file_v3 "github.com/envoyproxy/go-control-plane/envoy/extensions/access_loggers/file/v3"
+	envoy_req_without_query_v3 "github.com/envoyproxy/go-control-plane/envoy/extensions/formatter/req_without_query/v3"
 	"github.com/envoyproxy/go-control-plane/pkg/wellknown"
 	_struct "github.com/golang/protobuf/ptypes/struct"
 	"github.com/projectcontour/contour/internal/protobuf"
 	"github.com/projectcontour/contour/pkg/config"
 )
 
 // FileAccessLogEnvoy returns a new file based access log filter
-// that will output Envoy's default access logs.
-func FileAccessLogEnvoy(path string) []*envoy_accesslog_v3.AccessLog {
+func FileAccessLogEnvoy(path string, format string, extensions []string) []*envoy_accesslog_v3.AccessLog {
+	// Nil by default to defer to Envoy's default log format.
+	var logFormat *envoy_file_v3.FileAccessLog_LogFormat
+
+	if format != "" {
+		logFormat = &envoy_file_v3.FileAccessLog_LogFormat{
+			LogFormat: &envoy_config_core_v3.SubstitutionFormatString{
+				Format: &envoy_config_core_v3.SubstitutionFormatString_TextFormatSource{
+					TextFormatSource: &envoy_config_core_v3.DataSource{
+						Specifier: &envoy_config_core_v3.DataSource_InlineString{
+							InlineString: format,
+						},
+					},
+				},
+				Formatters: extensionConfig(extensions),
+			},
+		}
+	}
+
 	return []*envoy_accesslog_v3.AccessLog{{
 		Name: wellknown.FileAccessLog,
 		ConfigType: &envoy_accesslog_v3.AccessLog_TypedConfig{
 			TypedConfig: protobuf.MustMarshalAny(&envoy_file_v3.FileAccessLog{
-				Path: path,
-				// AccessLogFormat left blank to defer to Envoy's default log format.
+				Path:            path,
+				AccessLogFormat: logFormat,
 			}),
 		},
 	}}
 }
 
 // FileAccessLogJSON returns a new file based access log filter
 // that will log in JSON format
-func FileAccessLogJSON(path string, fields config.AccessLogFields) []*envoy_accesslog_v3.AccessLog {
+func FileAccessLogJSON(path string, fields config.AccessLogFields, extensions []string) []*envoy_accesslog_v3.AccessLog {
 
 	jsonformat := &_struct.Struct{
 		Fields: make(map[string]*_struct.Value),
@@ -59,6 +77,7 @@ func FileAccessLogJSON(path string, fields config.AccessLogFields) []*envoy_acce
 						Format: &envoy_config_core_v3.SubstitutionFormatString_JsonFormat{
 							JsonFormat: jsonformat,
 						},
+						Formatters: extensionConfig(extensions),
 					},
 				},
 			}),
@@ -73,3 +92,23 @@ func sv(s string) *_struct.Value {
 		},
 	}
 }
+
+// extensionConfig returns a list of extension configs required by the access log format.
+//
+// Note: When adding support for new formatter, update the list of extensions here and
+// add the corresponding extension in pkg/config/parameters.go AccessLogFormatterExtensions().
+// Currently only one extension exist in Envoy.
+func extensionConfig(extensions []string) []*envoy_config_core_v3.TypedExtensionConfig {
+	var config []*envoy_config_core_v3.TypedExtensionConfig
+
+	for _, e := range extensions {
+		if e == "envoy.formatter.req_without_query" {
+			config = append(config, &envoy_config_core_v3.TypedExtensionConfig{
+				Name:        "envoy.formatter.req_without_query",
+				TypedConfig: protobuf.MustMarshalAny(&envoy_req_without_query_v3.ReqWithoutQuery{ /* empty */ }),
+			})
+		}
+	}
+
+	return config
+}

internal/envoy/v3/accesslog_test.go

@@ -19,6 +19,7 @@ import (
 	envoy_accesslog_v3 "github.com/envoyproxy/go-control-plane/envoy/config/accesslog/v3"
 	envoy_config_core_v3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
 	envoy_file_v3 "github.com/envoyproxy/go-control-plane/envoy/extensions/access_loggers/file/v3"
+	envoy_req_without_query_v3 "github.com/envoyproxy/go-control-plane/envoy/extensions/formatter/req_without_query/v3"
 	"github.com/envoyproxy/go-control-plane/pkg/wellknown"
 	_struct "github.com/golang/protobuf/ptypes/struct"
 	"github.com/projectcontour/contour/internal/protobuf"
@@ -27,8 +28,10 @@ import (
 
 func TestFileAccessLog(t *testing.T) {
 	tests := map[string]struct {
-		path string
-		want []*envoy_accesslog_v3.AccessLog
+		path       string
+		format     string
+		extensions []string
+		want       []*envoy_accesslog_v3.AccessLog
 	}{
 		"stdout": {
 			path: "/dev/stdout",
@@ -41,10 +44,61 @@ func TestFileAccessLog(t *testing.T) {
 				},
 			}},
 		},
+		"custom log format": {
+			path:   "/dev/stdout",
+			format: "%CUSTOM%\n",
+			want: []*envoy_accesslog_v3.AccessLog{{
+				Name: wellknown.FileAccessLog,
+				ConfigType: &envoy_accesslog_v3.AccessLog_TypedConfig{
+					TypedConfig: protobuf.MustMarshalAny(&envoy_file_v3.FileAccessLog{
+						Path: "/dev/stdout",
+						AccessLogFormat: &envoy_file_v3.FileAccessLog_LogFormat{
+							LogFormat: &envoy_config_core_v3.SubstitutionFormatString{
+								Format: &envoy_config_core_v3.SubstitutionFormatString_TextFormatSource{
+									TextFormatSource: &envoy_config_core_v3.DataSource{
+										Specifier: &envoy_config_core_v3.DataSource_InlineString{
+											InlineString: "%CUSTOM%\n",
+										},
+									},
+								},
+							},
+						},
+					}),
+				},
+			}},
+		},
+		"custom log format with access log extension": {
+			path:       "/dev/stdout",
+			format:     "[%START_TIME%] \"%REQ_WITHOUT_QUERY(X-ENVOY-ORIGINAL-PATH?:PATH)%\"\n",
+			extensions: []string{"envoy.formatter.req_without_query"},
+			want: []*envoy_accesslog_v3.AccessLog{{
+				Name: wellknown.FileAccessLog,
+				ConfigType: &envoy_accesslog_v3.AccessLog_TypedConfig{
+					TypedConfig: protobuf.MustMarshalAny(&envoy_file_v3.FileAccessLog{
+						Path: "/dev/stdout",
+						AccessLogFormat: &envoy_file_v3.FileAccessLog_LogFormat{
+							LogFormat: &envoy_config_core_v3.SubstitutionFormatString{
+								Format: &envoy_config_core_v3.SubstitutionFormatString_TextFormatSource{
+									TextFormatSource: &envoy_config_core_v3.DataSource{
+										Specifier: &envoy_config_core_v3.DataSource_InlineString{
+											InlineString: "[%START_TIME%] \"%REQ_WITHOUT_QUERY(X-ENVOY-ORIGINAL-PATH?:PATH)%\"\n",
+										},
+									},
+								},
+								Formatters: []*envoy_config_core_v3.TypedExtensionConfig{{
+									Name:        "envoy.formatter.req_without_query",
+									TypedConfig: protobuf.MustMarshalAny(&envoy_req_without_query_v3.ReqWithoutQuery{ /* empty */ }),
+								}},
+							},
+						},
+					}),
+				},
+			}},
+		},
 	}
 	for name, tc := range tests {
 		t.Run(name, func(t *testing.T) {
-			got := FileAccessLogEnvoy(tc.path)
+			got := FileAccessLogEnvoy(tc.path, tc.format, tc.extensions)
 			protobuf.ExpectEqual(t, tc.want, got)
 		})
 	}
@@ -117,7 +171,7 @@ func TestJSONFileAccessLog(t *testing.T) {
 	}
 	for name, tc := range tests {
 		t.Run(name, func(t *testing.T) {
-			got := FileAccessLogJSON(tc.path, tc.headers)
+			got := FileAccessLogJSON(tc.path, tc.headers, nil)
 			protobuf.ExpectEqual(t, tc.want, got)
 		})
 	}