feat: add support for debug logging (#2107)

Co-authored-by: Jack Wotherspoon <[email protected]>

README.md

@@ -454,6 +454,13 @@ To enable Prometheus, use the `--prometheus` flag. This will start an HTTP
 server on localhost with a `/metrics` endpoint. The Prometheus namespace may
 optionally be set with `--prometheus-namespace`.
 
+## Debug logging
+
+To enable debug logging to report on internal certificate refresh operations,
+use the `--debug-logs` flag. Typical use of the Proxy should not require debug
+logs, but if you are surprised by the Proxy's behavior, debug logging should
+provide insight into internal operations and can help when reporting issues.
+
 ## Localhost Admin Server
 
 The Proxy includes support for an admin server on localhost. By default, the

cmd/root.go

@@ -262,6 +262,13 @@ Localhost Admin Server
   /quitquitquit. The admin server exits gracefully when it receives a POST
   request at /quitquitquit.
 
+Debug logging
+
+  On occasion, it can help to enable debug logging which will report on
+  internal certificate refresh operations. To enable debug logging, use:
+
+      ./cloud-sql-proxy <INSTANCE_CONNECTION_NAME> --debug-logs
+
 Waiting for Startup
 
   See the wait subcommand's help for details.
@@ -458,6 +465,8 @@ Instead prefer Application Default Credentials
 the Proxy will then pick-up automatically.`)
 	localFlags.BoolVarP(&c.conf.StructuredLogs, "structured-logs", "l", false,
 		"Enable structured logging with LogEntry format")
+	localFlags.BoolVar(&c.conf.DebugLogs, "debug-logs", false,
+		"Enable debug logging")
 	localFlags.Uint64Var(&c.conf.MaxConnections, "max-connections", 0,
 		"Limit the number of connections. Default is no limit.")
 	localFlags.DurationVar(&c.conf.WaitOnClose, "max-sigterm-delay", 0,

go.mod

@@ -3,31 +3,31 @@ module github.com/GoogleCloudPlatform/cloud-sql-proxy/v2
 go 1.20
 
 require (
-	cloud.google.com/go/cloudsqlconn v1.6.0
+	cloud.google.com/go/cloudsqlconn v1.7.0
 	contrib.go.opencensus.io/exporter/prometheus v0.4.2
 	contrib.go.opencensus.io/exporter/stackdriver v0.13.14
 	github.com/coreos/go-systemd/v22 v22.5.0
 	github.com/go-sql-driver/mysql v1.7.1
 	github.com/google/go-cmp v0.6.0
 	github.com/hanwen/go-fuse/v2 v2.5.0
-	github.com/jackc/pgx/v5 v5.5.2
+	github.com/jackc/pgx/v5 v5.5.3
 	github.com/microsoft/go-mssqldb v1.6.0
 	github.com/spf13/cobra v1.8.0
 	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.18.2
 	go.opencensus.io v0.24.0
 	go.uber.org/zap v1.26.0
-	golang.org/x/oauth2 v0.16.0
-	golang.org/x/sys v0.16.0
-	google.golang.org/api v0.156.0
+	golang.org/x/oauth2 v0.17.0
+	golang.org/x/sys v0.17.0
+	google.golang.org/api v0.164.0
 	gopkg.in/natefinch/lumberjack.v2 v2.2.1
 )
 
 require (
-	cloud.google.com/go/compute v1.23.3 // indirect
+	cloud.google.com/go/compute v1.23.4 // indirect
 	cloud.google.com/go/compute/metadata v0.2.3 // indirect
-	cloud.google.com/go/monitoring v1.17.0 // indirect
-	cloud.google.com/go/trace v1.10.4 // indirect
+	cloud.google.com/go/monitoring v1.17.1 // indirect
+	cloud.google.com/go/trace v1.10.5 // indirect
 	github.com/aws/aws-sdk-go v1.43.31 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/census-instrumentation/opencensus-proto v0.4.1 // indirect
@@ -36,14 +36,14 @@ require (
 	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/go-kit/log v0.2.1 // indirect
 	github.com/go-logfmt/logfmt v0.5.1 // indirect
-	github.com/go-logr/logr v1.3.0 // indirect
+	github.com/go-logr/logr v1.4.1 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/golang-sql/civil v0.0.0-20220223132316-b832511892a9 // indirect
 	github.com/golang-sql/sqlexp v0.1.0 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/google/s2a-go v0.1.7 // indirect
-	github.com/google/uuid v1.5.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.2 // indirect
 	github.com/googleapis/gax-go/v2 v2.12.0 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
@@ -68,23 +68,23 @@ require (
 	github.com/spf13/afero v1.11.0 // indirect
 	github.com/spf13/cast v1.6.0 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
-	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.46.1 // indirect
-	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.46.1 // indirect
-	go.opentelemetry.io/otel v1.21.0 // indirect
-	go.opentelemetry.io/otel/metric v1.21.0 // indirect
-	go.opentelemetry.io/otel/trace v1.21.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.47.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.47.0 // indirect
+	go.opentelemetry.io/otel v1.23.0 // indirect
+	go.opentelemetry.io/otel/metric v1.23.0 // indirect
+	go.opentelemetry.io/otel/trace v1.23.0 // indirect
 	go.uber.org/multierr v1.10.0 // indirect
-	golang.org/x/crypto v0.18.0 // indirect
+	golang.org/x/crypto v0.19.0 // indirect
 	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
-	golang.org/x/net v0.20.0 // indirect
+	golang.org/x/net v0.21.0 // indirect
 	golang.org/x/sync v0.6.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/time v0.5.0 // indirect
 	google.golang.org/appengine v1.6.8 // indirect
-	google.golang.org/genproto v0.0.0-20240102182953-50ed04b92917 // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20231212172506-995d672761c0 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240116215550-a9fa1716bcac // indirect
-	google.golang.org/grpc v1.60.1 // indirect
+	google.golang.org/genproto v0.0.0-20240205150955-31a09d347014 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20240125205218-1f4bbc51befe // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240213162025-012b6fc9bca9 // indirect
+	google.golang.org/grpc v1.61.0 // indirect
 	google.golang.org/protobuf v1.32.0 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect