From 35536c6f8903945dcf656ad0dd5b43022987d8e0 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 10:39:09 -0500
Subject: [PATCH 01/14] init commit

---
 go.mod           |  1 +
 go.sum           |  4 ++++
 server/logger.go | 41 ++++++++++++++++++++++++++++++++++++
 server/util.go   | 54 +++++++++++++++++++++++++++++++++---------------
 4 files changed, 83 insertions(+), 17 deletions(-)
 create mode 100644 server/logger.go

diff --git a/go.mod b/go.mod
index 8163ebbfbe62..b437a1006342 100644
--- a/go.mod
+++ b/go.mod
@@ -35,6 +35,7 @@ require (
 	github.com/prometheus/common v0.15.0
 	github.com/rakyll/statik v0.1.7
 	github.com/regen-network/cosmos-proto v0.3.0
+	github.com/rs/zerolog v1.20.0
 	github.com/spf13/afero v1.2.2 // indirect
 	github.com/spf13/cast v1.3.1
 	github.com/spf13/cobra v1.1.1
diff --git a/go.sum b/go.sum
index b6ae47006000..4542327b0e4b 100644
--- a/go.sum
+++ b/go.sum
@@ -481,6 +481,9 @@ github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6L
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/rs/cors v1.7.0 h1:+88SsELBHx5r+hZ8TCkggzSstaWNbDvThkVK8H6f9ik=
 github.com/rs/cors v1.7.0/go.mod h1:gFx+x8UowdsKA9AchylcLynDq+nNFfI8FkUZdN/jGCU=
+github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
+github.com/rs/zerolog v1.20.0 h1:38k9hgtUBdxFwE34yS8rTHmHBa4eN16E4DJlv177LNs=
+github.com/rs/zerolog v1.20.0/go.mod h1:IzD0RJ65iWH0w97OQQebJEvTZYvsCUm9WVLWBQrJRjo=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
@@ -726,6 +729,7 @@ golang.org/x/tools v0.0.0-20190606124116-d0a3d012864b/go.mod h1:/rFqwRUd4F7ZHNgw
 golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190628153133-6cdbf07be9d0/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190816200558-6889da9d5479/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20190828213141-aed303cbaa74/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20190911174233-4f2ddba30aff/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191012152004-8de300cfc20a/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191029041327-9cc4af7d6b2c/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
diff --git a/server/logger.go b/server/logger.go
new file mode 100644
index 000000000000..f4d9479dbf2a
--- /dev/null
+++ b/server/logger.go
@@ -0,0 +1,41 @@
+package server
+
+import (
+	"github.com/rs/zerolog"
+	tmlog "github.com/tendermint/tendermint/libs/log"
+)
+
+var _ tmlog.Logger = (*ZeroLogWrapper)(nil)
+
+type ZeroLogWrapper struct {
+	zerolog.Logger
+}
+
+func (z ZeroLogWrapper) Info(msg string, keyVals ...interface{}) {
+	z.Logger.Info().Fields(getLogFields(keyVals)).Msg(msg)
+}
+
+func (z ZeroLogWrapper) Error(msg string, keyVals ...interface{}) {
+	z.Logger.Error().Fields(getLogFields(keyVals)).Msg(msg)
+}
+
+func (z ZeroLogWrapper) Debug(msg string, keyVals ...interface{}) {
+	z.Logger.Debug().Fields(getLogFields(keyVals)).Msg(msg)
+}
+
+func (z ZeroLogWrapper) With(keyVals ...interface{}) tmlog.Logger {
+	return ZeroLogWrapper{z.Logger.With().Fields(getLogFields(keyVals)).Logger()}
+}
+
+func getLogFields(keyVals ...interface{}) map[string]interface{} {
+	if len(keyVals)%2 != 0 {
+		return nil
+	}
+
+	fields := make(map[string]interface{})
+	for i := 0; i < len(keyVals); i += 2 {
+		fields[keyVals[i].(string)] = keyVals[i+1]
+	}
+
+	return fields
+}
diff --git a/server/util.go b/server/util.go
index 7118d5b8d556..ca9a78475643 100644
--- a/server/util.go
+++ b/server/util.go
@@ -14,12 +14,12 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 	tmcfg "github.com/tendermint/tendermint/config"
-	tmcli "github.com/tendermint/tendermint/libs/cli"
-	tmflags "github.com/tendermint/tendermint/libs/cli/flags"
-	"github.com/tendermint/tendermint/libs/log"
+	tmlog "github.com/tendermint/tendermint/libs/log"
 	dbm "github.com/tendermint/tm-db"
 
 	"github.com/cosmos/cosmos-sdk/client/flags"
@@ -39,7 +39,7 @@ const ServerContextKey = sdk.ContextKey("server.context")
 type Context struct {
 	Viper  *viper.Viper
 	Config *tmcfg.Config
-	Logger log.Logger
+	Logger tmlog.Logger
 }
 
 // ErrorCode contains the exit code for server exit.
@@ -52,10 +52,14 @@ func (e ErrorCode) Error() string {
 }
 
 func NewDefaultContext() *Context {
-	return NewContext(viper.New(), tmcfg.DefaultConfig(), log.NewTMLogger(log.NewSyncWriter(os.Stdout)))
+	return NewContext(
+		viper.New(),
+		tmcfg.DefaultConfig(),
+		ZeroLogWrapper{log.Logger},
+	)
 }
 
-func NewContext(v *viper.Viper, config *tmcfg.Config, logger log.Logger) *Context {
+func NewContext(v *viper.Viper, config *tmcfg.Config, logger tmlog.Logger) *Context {
 	return &Context{v, config, logger}
 }
 
@@ -86,27 +90,43 @@ func InterceptConfigsPreRunHandler(cmd *cobra.Command) error {
 	serverCtx.Viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_", "-", "_"))
 	serverCtx.Viper.AutomaticEnv()
 
-	// Intercept configuration files, using both Viper instances separately
+	// intercept configuration files, using both Viper instances separately
 	config, err := interceptConfigs(serverCtx.Viper)
 	if err != nil {
 		return err
 	}
-	// Return value is a tendermint configuration object
+
+	// return value is a tendermint configuration object
 	serverCtx.Config = config
 
-	logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
-	logger, err = tmflags.ParseLogLevel(config.LogLevel, logger, tmcfg.DefaultLogLevel())
-	if err != nil {
-		return err
+	var logWriter io.Writer
+	if strings.ToLower(config.LogFormat) == tmcfg.LogFormatPlain {
+		logWriter = zerolog.ConsoleWriter{Out: os.Stderr}
+	} else {
+		logWriter = os.Stderr
 	}
 
-	// Check if the tendermint flag for trace logging is set
-	// if it is then setup a tracing logger in this app as well
-	if serverCtx.Viper.GetBool(tmcli.TraceFlag) {
-		logger = log.NewTracingLogger(logger)
+	// logLvl, err := zerolog.ParseLevel(config.LogLevel)
+	logLvl, err := zerolog.ParseLevel("info")
+	if err != nil {
+		return fmt.Errorf("failed to parse log level (%s): %w", config.LogLevel, err)
 	}
 
-	serverCtx.Logger = logger.With("module", "main")
+	serverCtx.Logger = ZeroLogWrapper{zerolog.New(logWriter).Level(logLvl).With().Timestamp().Logger()}
+
+	// logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
+	// logger, err = tmflags.ParseLogLevel(config.LogLevel, logger, tmcfg.DefaultLogLevel())
+	// if err != nil {
+	// 	return err
+	// }
+
+	// // Check if the tendermint flag for trace logging is set
+	// // if it is then setup a tracing logger in this app as well
+	// if serverCtx.Viper.GetBool(tmcli.TraceFlag) {
+	// 	logger = log.NewTracingLogger(logger)
+	// }
+
+	// serverCtx.Logger = logger.With("module", "main")
 
 	return SetCmdServerContext(cmd, serverCtx)
 }

From fde418db0dbfe249cc5d355ad75bb24747166076 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 11:08:05 -0500
Subject: [PATCH 02/14] server: use flags

---
 client/flags/flags.go   |  4 ++++
 server/util.go          | 22 ++++------------------
 simapp/simd/cmd/root.go |  5 ++++-
 3 files changed, 12 insertions(+), 19 deletions(-)

diff --git a/client/flags/flags.go b/client/flags/flags.go
index 2131c376397e..72bcabcd60db 100644
--- a/client/flags/flags.go
+++ b/client/flags/flags.go
@@ -65,6 +65,10 @@ const (
 	FlagCountTotal       = "count-total"
 	FlagTimeoutHeight    = "timeout-height"
 	FlagKeyAlgorithm     = "algo"
+
+	// Tendermint logging flags
+	FlagLogLevel  = "log_level"
+	FlagLogFormat = "log_format"
 )
 
 // LineBreak can be included in a command list to provide a blank line
diff --git a/server/util.go b/server/util.go
index ca9a78475643..e461a12fb843 100644
--- a/server/util.go
+++ b/server/util.go
@@ -100,34 +100,20 @@ func InterceptConfigsPreRunHandler(cmd *cobra.Command) error {
 	serverCtx.Config = config
 
 	var logWriter io.Writer
-	if strings.ToLower(config.LogFormat) == tmcfg.LogFormatPlain {
+	if strings.ToLower(serverCtx.Viper.GetString(flags.FlagLogFormat)) == tmcfg.LogFormatPlain {
 		logWriter = zerolog.ConsoleWriter{Out: os.Stderr}
 	} else {
 		logWriter = os.Stderr
 	}
 
-	// logLvl, err := zerolog.ParseLevel(config.LogLevel)
-	logLvl, err := zerolog.ParseLevel("info")
+	logLvlStr := serverCtx.Viper.GetString(flags.FlagLogLevel)
+	logLvl, err := zerolog.ParseLevel(logLvlStr)
 	if err != nil {
-		return fmt.Errorf("failed to parse log level (%s): %w", config.LogLevel, err)
+		return fmt.Errorf("failed to parse log level (%s): %w", logLvlStr, err)
 	}
 
 	serverCtx.Logger = ZeroLogWrapper{zerolog.New(logWriter).Level(logLvl).With().Timestamp().Logger()}
 
-	// logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
-	// logger, err = tmflags.ParseLogLevel(config.LogLevel, logger, tmcfg.DefaultLogLevel())
-	// if err != nil {
-	// 	return err
-	// }
-
-	// // Check if the tendermint flag for trace logging is set
-	// // if it is then setup a tracing logger in this app as well
-	// if serverCtx.Viper.GetBool(tmcli.TraceFlag) {
-	// 	logger = log.NewTracingLogger(logger)
-	// }
-
-	// serverCtx.Logger = logger.With("module", "main")
-
 	return SetCmdServerContext(cmd, serverCtx)
 }
 
diff --git a/simapp/simd/cmd/root.go b/simapp/simd/cmd/root.go
index dd6132095c88..847a31f21168 100644
--- a/simapp/simd/cmd/root.go
+++ b/simapp/simd/cmd/root.go
@@ -6,8 +6,10 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/rs/zerolog"
 	"github.com/spf13/cast"
 	"github.com/spf13/cobra"
+	tmcfg "github.com/tendermint/tendermint/config"
 	tmcli "github.com/tendermint/tendermint/libs/cli"
 	"github.com/tendermint/tendermint/libs/log"
 	dbm "github.com/tendermint/tm-db"
@@ -79,7 +81,8 @@ func Execute(rootCmd *cobra.Command) error {
 	ctx = context.WithValue(ctx, client.ClientContextKey, &client.Context{})
 	ctx = context.WithValue(ctx, server.ServerContextKey, srvCtx)
 
-	rootCmd.PersistentFlags().String("log_level", srvCtx.Config.LogLevel, "The logging level in the format of <module>:<level>,...")
+	rootCmd.PersistentFlags().String(flags.FlagLogLevel, zerolog.InfoLevel.String(), "The logging level (trace|debug|info|warn|error|fatal|panic)")
+	rootCmd.PersistentFlags().String(flags.FlagLogFormat, tmcfg.LogFormatJSON, "The logging format (json|plain)")
 
 	executor := tmcli.PrepareBaseCmd(rootCmd, "", simapp.DefaultNodeHome)
 	return executor.ExecuteContext(ctx)

From 35da7bc6d8a6ae4474ee74ae1a351556eff6d18d Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 11:18:12 -0500
Subject: [PATCH 03/14] server: godoc++

---
 server/logger.go | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/server/logger.go b/server/logger.go
index f4d9479dbf2a..8e96315d187e 100644
--- a/server/logger.go
+++ b/server/logger.go
@@ -7,22 +7,36 @@ import (
 
 var _ tmlog.Logger = (*ZeroLogWrapper)(nil)
 
+// ZeroLogWrapper provides a wrapper around a zerolog.Logger instance. It implements
+// Tendermint's Logger interface.
 type ZeroLogWrapper struct {
 	zerolog.Logger
 }
 
+// Info implements Tendermint's Logger interface and logs with level INFO. A set
+// of key/value tuples may be provided to add context to the log. The number of
+// tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Info(msg string, keyVals ...interface{}) {
 	z.Logger.Info().Fields(getLogFields(keyVals)).Msg(msg)
 }
 
+// Error implements Tendermint's Logger interface and logs with level ERR. A set
+// of key/value tuples may be provided to add context to the log. The number of
+// tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Error(msg string, keyVals ...interface{}) {
 	z.Logger.Error().Fields(getLogFields(keyVals)).Msg(msg)
 }
 
+// Debug implements Tendermint's Logger interface and logs with level DEBUG. A set
+// of key/value tuples may be provided to add context to the log. The number of
+// tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Debug(msg string, keyVals ...interface{}) {
 	z.Logger.Debug().Fields(getLogFields(keyVals)).Msg(msg)
 }
 
+// With returns a new wrapped logger with additional context provided by a set
+// of key/value tuples. The number of tuples must be even and the key of the
+// tuple must be a string.
 func (z ZeroLogWrapper) With(keyVals ...interface{}) tmlog.Logger {
 	return ZeroLogWrapper{z.Logger.With().Fields(getLogFields(keyVals)).Logger()}
 }

From aee6a0c6ae021f8c580f1dd8dd3e257e133b9bcb Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:31:30 -0500
Subject: [PATCH 04/14] updates

---
 contrib/images/simd-env/Dockerfile | 2 +-
 server/logger.go                   | 8 ++++----
 x/bank/keeper/keeper.go            | 2 +-
 x/bank/keeper/view.go              | 2 +-
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/contrib/images/simd-env/Dockerfile b/contrib/images/simd-env/Dockerfile
index 3be7eb5c847e..1ccaeac657db 100644
--- a/contrib/images/simd-env/Dockerfile
+++ b/contrib/images/simd-env/Dockerfile
@@ -12,7 +12,7 @@ VOLUME [ /simd ]
 WORKDIR /simd
 EXPOSE 26656 26657
 ENTRYPOINT ["/usr/bin/wrapper.sh"]
-CMD ["start"]
+CMD ["start", "--log_format", "plain"]
 STOPSIGNAL SIGTERM
 
 COPY wrapper.sh /usr/bin/wrapper.sh
diff --git a/server/logger.go b/server/logger.go
index 8e96315d187e..e6f6f8c1110f 100644
--- a/server/logger.go
+++ b/server/logger.go
@@ -17,28 +17,28 @@ type ZeroLogWrapper struct {
 // of key/value tuples may be provided to add context to the log. The number of
 // tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Info(msg string, keyVals ...interface{}) {
-	z.Logger.Info().Fields(getLogFields(keyVals)).Msg(msg)
+	z.Logger.Info().Fields(getLogFields(keyVals...)).Msg(msg)
 }
 
 // Error implements Tendermint's Logger interface and logs with level ERR. A set
 // of key/value tuples may be provided to add context to the log. The number of
 // tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Error(msg string, keyVals ...interface{}) {
-	z.Logger.Error().Fields(getLogFields(keyVals)).Msg(msg)
+	z.Logger.Error().Fields(getLogFields(keyVals...)).Msg(msg)
 }
 
 // Debug implements Tendermint's Logger interface and logs with level DEBUG. A set
 // of key/value tuples may be provided to add context to the log. The number of
 // tuples must be even and the key of the tuple must be a string.
 func (z ZeroLogWrapper) Debug(msg string, keyVals ...interface{}) {
-	z.Logger.Debug().Fields(getLogFields(keyVals)).Msg(msg)
+	z.Logger.Debug().Fields(getLogFields(keyVals...)).Msg(msg)
 }
 
 // With returns a new wrapped logger with additional context provided by a set
 // of key/value tuples. The number of tuples must be even and the key of the
 // tuple must be a string.
 func (z ZeroLogWrapper) With(keyVals ...interface{}) tmlog.Logger {
-	return ZeroLogWrapper{z.Logger.With().Fields(getLogFields(keyVals)).Logger()}
+	return ZeroLogWrapper{z.Logger.With().Fields(getLogFields(keyVals...)).Logger()}
 }
 
 func getLogFields(keyVals ...interface{}) map[string]interface{} {
diff --git a/x/bank/keeper/keeper.go b/x/bank/keeper/keeper.go
index 2fd76ea58c34..8ceace8c0daa 100644
--- a/x/bank/keeper/keeper.go
+++ b/x/bank/keeper/keeper.go
@@ -341,7 +341,7 @@ func (k BaseKeeper) MintCoins(ctx sdk.Context, moduleName string, amt sdk.Coins)
 	k.SetSupply(ctx, supply)
 
 	logger := k.Logger(ctx)
-	logger.Info(fmt.Sprintf("minted %s from %s module account", amt.String(), moduleName))
+	logger.Info("minted coins from module account", "amount", amt.String(), "from", moduleName)
 
 	return nil
 }
diff --git a/x/bank/keeper/view.go b/x/bank/keeper/view.go
index 2c4c4239bc23..d4bcabad2b62 100644
--- a/x/bank/keeper/view.go
+++ b/x/bank/keeper/view.go
@@ -49,7 +49,7 @@ func NewBaseViewKeeper(cdc codec.BinaryMarshaler, storeKey sdk.StoreKey, ak type
 
 // Logger returns a module-specific logger.
 func (k BaseViewKeeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // HasBalance returns whether or not an account has at least amt balance.

From 823bfe85f2d5b816e2b5dd9c2b67152e8bb8c95f Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:36:58 -0500
Subject: [PATCH 05/14] baseapp: update logging

---
 baseapp/abci.go | 63 ++++++++++++++++++++++++++++++++++---------------
 1 file changed, 44 insertions(+), 19 deletions(-)

diff --git a/baseapp/abci.go b/baseapp/abci.go
index b46afd6c73ef..aaa48bb8c0ab 100644
--- a/baseapp/abci.go
+++ b/baseapp/abci.go
@@ -291,7 +291,7 @@ func (app *BaseApp) Commit() (res abci.ResponseCommit) {
 	// MultiStore (app.cms) so when Commit() is called is persists those values.
 	app.deliverState.ms.Write()
 	commitID := app.cms.Commit()
-	app.logger.Debug("Commit synced", "commit", fmt.Sprintf("%X", commitID))
+	app.logger.Info("commit synced", "commit", fmt.Sprintf("%X", commitID))
 
 	// Reset the Check state to the latest committed.
 	//
@@ -358,22 +358,27 @@ func (app *BaseApp) snapshot(height int64) {
 		app.logger.Info("snapshot manager not configured")
 		return
 	}
-	app.logger.Info("Creating state snapshot", "height", height)
+
+	app.logger.Info("creating state snapshot", "height", height)
+
 	snapshot, err := app.snapshotManager.Create(uint64(height))
 	if err != nil {
-		app.logger.Error("Failed to create state snapshot", "height", height, "err", err)
+		app.logger.Error("failed to create state snapshot", "height", height, "err", err)
 		return
 	}
-	app.logger.Info("Completed state snapshot", "height", height, "format", snapshot.Format)
+
+	app.logger.Info("completed state snapshot", "height", height, "format", snapshot.Format)
 
 	if app.snapshotKeepRecent > 0 {
-		app.logger.Debug("Pruning state snapshots")
+		app.logger.Debug("pruning state snapshots")
+
 		pruned, err := app.snapshotManager.Prune(app.snapshotKeepRecent)
 		if err != nil {
 			app.logger.Error("Failed to prune state snapshots", "err", err)
 			return
 		}
-		app.logger.Debug("Pruned state snapshots", "pruned", pruned)
+
+		app.logger.Debug("pruned state snapshots", "pruned", pruned)
 	}
 }
 
@@ -433,13 +438,14 @@ func (app *BaseApp) ListSnapshots(req abci.RequestListSnapshots) abci.ResponseLi
 
 	snapshots, err := app.snapshotManager.List()
 	if err != nil {
-		app.logger.Error("Failed to list snapshots", "err", err)
+		app.logger.Error("failed to list snapshots", "err", err)
 		return resp
 	}
+
 	for _, snapshot := range snapshots {
 		abciSnapshot, err := snapshot.ToABCI()
 		if err != nil {
-			app.logger.Error("Failed to list snapshots", "err", err)
+			app.logger.Error("failed to list snapshots", "err", err)
 			return resp
 		}
 		resp.Snapshots = append(resp.Snapshots, &abciSnapshot)
@@ -455,8 +461,13 @@ func (app *BaseApp) LoadSnapshotChunk(req abci.RequestLoadSnapshotChunk) abci.Re
 	}
 	chunk, err := app.snapshotManager.LoadChunk(req.Height, req.Format, req.Chunk)
 	if err != nil {
-		app.logger.Error("Failed to load snapshot chunk", "height", req.Height, "format", req.Format,
-			"chunk", req.Chunk, "err")
+		app.logger.Error(
+			"failed to load snapshot chunk",
+			"height", req.Height,
+			"format", req.Format,
+			"chunk", req.Chunk,
+			"err", err,
+		)
 		return abci.ResponseLoadSnapshotChunk{}
 	}
 	return abci.ResponseLoadSnapshotChunk{Chunk: chunk}
@@ -470,15 +481,16 @@ func (app *BaseApp) OfferSnapshot(req abci.RequestOfferSnapshot) abci.ResponseOf
 	}
 
 	if req.Snapshot == nil {
-		app.logger.Error("Received nil snapshot")
+		app.logger.Error("received nil snapshot")
 		return abci.ResponseOfferSnapshot{Result: abci.ResponseOfferSnapshot_REJECT}
 	}
 
 	snapshot, err := snapshottypes.SnapshotFromABCI(req.Snapshot)
 	if err != nil {
-		app.logger.Error("Failed to decode snapshot metadata", "err", err)
+		app.logger.Error("failed to decode snapshot metadata", "err", err)
 		return abci.ResponseOfferSnapshot{Result: abci.ResponseOfferSnapshot_REJECT}
 	}
+
 	err = app.snapshotManager.Restore(snapshot)
 	switch {
 	case err == nil:
@@ -488,13 +500,22 @@ func (app *BaseApp) OfferSnapshot(req abci.RequestOfferSnapshot) abci.ResponseOf
 		return abci.ResponseOfferSnapshot{Result: abci.ResponseOfferSnapshot_REJECT_FORMAT}
 
 	case errors.Is(err, snapshottypes.ErrInvalidMetadata):
-		app.logger.Error("Rejecting invalid snapshot", "height", req.Snapshot.Height,
-			"format", req.Snapshot.Format, "err", err)
+		app.logger.Error(
+			"rejecting invalid snapshot",
+			"height", req.Snapshot.Height,
+			"format", req.Snapshot.Format,
+			"err", err,
+		)
 		return abci.ResponseOfferSnapshot{Result: abci.ResponseOfferSnapshot_REJECT}
 
 	default:
-		app.logger.Error("Failed to restore snapshot", "height", req.Snapshot.Height,
-			"format", req.Snapshot.Format, "err", err)
+		app.logger.Error(
+			"failed to restore snapshot",
+			"height", req.Snapshot.Height,
+			"format", req.Snapshot.Format,
+			"err", err,
+		)
+
 		// We currently don't support resetting the IAVL stores and retrying a different snapshot,
 		// so we ask Tendermint to abort all snapshot restoration.
 		return abci.ResponseOfferSnapshot{Result: abci.ResponseOfferSnapshot_ABORT}
@@ -514,8 +535,12 @@ func (app *BaseApp) ApplySnapshotChunk(req abci.RequestApplySnapshotChunk) abci.
 		return abci.ResponseApplySnapshotChunk{Result: abci.ResponseApplySnapshotChunk_ACCEPT}
 
 	case errors.Is(err, snapshottypes.ErrChunkHashMismatch):
-		app.logger.Error("Chunk checksum mismatch, rejecting sender and requesting refetch",
-			"chunk", req.Index, "sender", req.Sender, "err", err)
+		app.logger.Error(
+			"chunk checksum mismatch; rejecting sender and requesting refetch",
+			"chunk", req.Index,
+			"sender", req.Sender,
+			"err", err,
+		)
 		return abci.ResponseApplySnapshotChunk{
 			Result:        abci.ResponseApplySnapshotChunk_RETRY,
 			RefetchChunks: []uint32{req.Index},
@@ -523,7 +548,7 @@ func (app *BaseApp) ApplySnapshotChunk(req abci.RequestApplySnapshotChunk) abci.
 		}
 
 	default:
-		app.logger.Error("Failed to restore snapshot", "err", err)
+		app.logger.Error("failed to restore snapshot", "err", err)
 		return abci.ResponseApplySnapshotChunk{Result: abci.ResponseApplySnapshotChunk_ABORT}
 	}
 }

From b78ce015db5ffdcb9aa7ca13491f7d90b332de33 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:39:49 -0500
Subject: [PATCH 06/14] logging updates

---
 server/start.go         | 6 +++---
 x/auth/keeper/keeper.go | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/server/start.go b/server/start.go
index e4ecd47de601..d3af7db42ca4 100644
--- a/server/start.go
+++ b/server/start.go
@@ -240,17 +240,17 @@ func startInProcess(ctx *Context, clientCtx client.Context, appCreator types.App
 		genDocProvider,
 		node.DefaultDBProvider,
 		node.DefaultMetricsProvider(cfg.Instrumentation),
-		ctx.Logger.With("module", "node"),
+		ctx.Logger,
 	)
 	if err != nil {
 		return err
 	}
-	ctx.Logger.Debug("Initialization: tmNode created")
 
+	ctx.Logger.Debug("initialization: tmNode created")
 	if err := tmNode.Start(); err != nil {
 		return err
 	}
-	ctx.Logger.Debug("Initialization: tmNode started")
+	ctx.Logger.Debug("initialization: tmNode started")
 
 	config := config.GetConfig(ctx.Viper)
 
diff --git a/x/auth/keeper/keeper.go b/x/auth/keeper/keeper.go
index 75724f7d3c81..abc1cdabfc29 100644
--- a/x/auth/keeper/keeper.go
+++ b/x/auth/keeper/keeper.go
@@ -86,7 +86,7 @@ func NewAccountKeeper(
 
 // Logger returns a module-specific logger.
 func (ak AccountKeeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // GetPubKey Returns the PubKey of the account at address

From 6781f7eb86069a60d57f468a9a9e47b3515fac4e Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:41:09 -0500
Subject: [PATCH 07/14] x/bank: update logging

---
 x/bank/keeper/keeper.go | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/x/bank/keeper/keeper.go b/x/bank/keeper/keeper.go
index 8ceace8c0daa..7661c1d31573 100644
--- a/x/bank/keeper/keeper.go
+++ b/x/bank/keeper/keeper.go
@@ -1,7 +1,6 @@
 package keeper
 
 import (
-	"fmt"
 	"time"
 
 	"github.com/cosmos/cosmos-sdk/codec"
@@ -369,7 +368,7 @@ func (k BaseKeeper) BurnCoins(ctx sdk.Context, moduleName string, amt sdk.Coins)
 	k.SetSupply(ctx, supply)
 
 	logger := k.Logger(ctx)
-	logger.Info(fmt.Sprintf("burned %s from %s module account", amt.String(), moduleName))
+	logger.Info("burned tokens from module account", "amount", amt.String(), "from", moduleName)
 
 	return nil
 }

From a9c586630b84f6365cf213fdf851cf15aaf98de0 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:45:32 -0500
Subject: [PATCH 08/14] logging updates

---
 x/crisis/keeper/keeper.go                 |  4 ++--
 x/distribution/keeper/delegation.go       | 10 +++++++---
 x/distribution/keeper/keeper.go           |  2 +-
 x/distribution/keeper/proposal_handler.go |  5 ++---
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/x/crisis/keeper/keeper.go b/x/crisis/keeper/keeper.go
index 8a78c936c3f1..818e272d9038 100644
--- a/x/crisis/keeper/keeper.go
+++ b/x/crisis/keeper/keeper.go
@@ -44,7 +44,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // RegisterRoute register the routes for each of the invariants
@@ -76,7 +76,7 @@ func (k Keeper) AssertInvariants(ctx sdk.Context) {
 	invarRoutes := k.Routes()
 	n := len(invarRoutes)
 	for i, ir := range invarRoutes {
-		logger.Debug("Asserting cirisis invariants", "inv", fmt.Sprint(i, "/", n))
+		logger.Info("asserting cirisis invariants", "inv", fmt.Sprint(i, "/", n))
 		if res, stop := ir.Invar(ctx); stop {
 			// TODO: Include app name as part of context to allow for this to be
 			// variable.
diff --git a/x/distribution/keeper/delegation.go b/x/distribution/keeper/delegation.go
index 7d1e66611b83..61631da5dc22 100644
--- a/x/distribution/keeper/delegation.go
+++ b/x/distribution/keeper/delegation.go
@@ -152,9 +152,13 @@ func (k Keeper) withdrawDelegationRewards(ctx sdk.Context, val stakingtypes.Vali
 	rewards := rewardsRaw.Intersect(outstanding)
 	if !rewards.IsEqual(rewardsRaw) {
 		logger := k.Logger(ctx)
-		logger.Info(fmt.Sprintf("missing rewards rounding error, delegator %v"+
-			"withdrawing rewards from validator %v, should have received %v, got %v",
-			val.GetOperator(), del.GetDelegatorAddr(), rewardsRaw, rewards))
+		logger.Info(
+			"rounding error withdrawing rewards from validator",
+			"delegator", del.GetDelegatorAddr().String(),
+			"validator", val.GetOperator().String(),
+			"got", rewards.String(),
+			"expected", rewardsRaw.String(),
+		)
 	}
 
 	// truncate coins, return remainder to community pool
diff --git a/x/distribution/keeper/keeper.go b/x/distribution/keeper/keeper.go
index 0c2f25c83af4..0d5c32f78eb0 100644
--- a/x/distribution/keeper/keeper.go
+++ b/x/distribution/keeper/keeper.go
@@ -57,7 +57,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // SetWithdrawAddr sets a new address that will receive the rewards upon withdrawal
diff --git a/x/distribution/keeper/proposal_handler.go b/x/distribution/keeper/proposal_handler.go
index 9f9c4ec9e4a9..efea719977e2 100644
--- a/x/distribution/keeper/proposal_handler.go
+++ b/x/distribution/keeper/proposal_handler.go
@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"fmt"
-
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/x/distribution/types"
@@ -23,6 +21,7 @@ func HandleCommunityPoolSpendProposal(ctx sdk.Context, k Keeper, p *types.Commun
 	}
 
 	logger := k.Logger(ctx)
-	logger.Info(fmt.Sprintf("transferred %s from the community pool to recipient %s", p.Amount, p.Recipient))
+	logger.Info("transferred from the community pool to recipient", "amount", p.Amount.String(), "recipient", p.Recipient)
+
 	return nil
 }

From be4a1eeaea15b2991e2c2f1a408253894f1ed107 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:45:47 -0500
Subject: [PATCH 09/14] lint++

---
 x/distribution/keeper/proposal_handler.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/x/distribution/keeper/proposal_handler.go b/x/distribution/keeper/proposal_handler.go
index efea719977e2..d96bfc64908c 100644
--- a/x/distribution/keeper/proposal_handler.go
+++ b/x/distribution/keeper/proposal_handler.go
@@ -11,10 +11,12 @@ func HandleCommunityPoolSpendProposal(ctx sdk.Context, k Keeper, p *types.Commun
 	if k.blockedAddrs[p.Recipient] {
 		return sdkerrors.Wrapf(sdkerrors.ErrUnauthorized, "%s is not allowed to receive external funds", p.Recipient)
 	}
+
 	recipient, addrErr := sdk.AccAddressFromBech32(p.Recipient)
 	if addrErr != nil {
 		return addrErr
 	}
+
 	err := k.DistributeFromFeePool(ctx, p.Amount, recipient)
 	if err != nil {
 		return err

From fbd45f210773d96f7170239423243833ebfbb988 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:52:08 -0500
Subject: [PATCH 10/14] logging updates

---
 x/evidence/keeper/keeper.go |  2 +-
 x/gov/abci.go               | 20 ++++++++++----------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/x/evidence/keeper/keeper.go b/x/evidence/keeper/keeper.go
index e15cd74c8a07..8a2bfa686834 100644
--- a/x/evidence/keeper/keeper.go
+++ b/x/evidence/keeper/keeper.go
@@ -40,7 +40,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // SetRouter sets the Evidence Handler router for the x/evidence module. Note,
diff --git a/x/gov/abci.go b/x/gov/abci.go
index f31e15062788..f9815e0fb812 100644
--- a/x/gov/abci.go
+++ b/x/gov/abci.go
@@ -30,13 +30,13 @@ func EndBlocker(ctx sdk.Context, keeper keeper.Keeper) {
 		)
 
 		logger.Info(
-			fmt.Sprintf("proposal %d (%s) didn't meet minimum deposit of %s (had only %s); deleted",
-				proposal.ProposalId,
-				proposal.GetTitle(),
-				keeper.GetDepositParams(ctx).MinDeposit,
-				proposal.TotalDeposit,
-			),
+			"proposal did not meet minimum deposit; deleted",
+			"proposal", proposal.ProposalId,
+			"title", proposal.GetTitle(),
+			"min_deposit", keeper.GetDepositParams(ctx).MinDeposit.String(),
+			"total_deposit", proposal.TotalDeposit.String(),
 		)
+
 		return false
 	})
 
@@ -90,10 +90,10 @@ func EndBlocker(ctx sdk.Context, keeper keeper.Keeper) {
 		keeper.RemoveFromActiveProposalQueue(ctx, proposal.ProposalId, proposal.VotingEndTime)
 
 		logger.Info(
-			fmt.Sprintf(
-				"proposal %d (%s) tallied; result: %s",
-				proposal.ProposalId, proposal.GetTitle(), logMsg,
-			),
+			"proposal tallied",
+			"proposal", proposal.ProposalId,
+			"title", proposal.GetTitle(),
+			"result", logMsg,
 		)
 
 		ctx.EventManager().EmitEvent(

From 4f53a922f9850912c38ca454c7a82811f37c4518 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 12:55:53 -0500
Subject: [PATCH 11/14] logging updates

---
 x/gov/keeper/keeper.go                       | 2 +-
 x/ibc/applications/transfer/keeper/keeper.go | 4 +---
 x/ibc/core/02-client/keeper/keeper.go        | 2 +-
 x/ibc/core/03-connection/keeper/keeper.go    | 4 +---
 x/ibc/core/04-channel/keeper/keeper.go       | 3 +--
 x/ibc/core/05-port/keeper/keeper.go          | 2 +-
 x/mint/keeper/keeper.go                      | 4 +---
 x/params/keeper/keeper.go                    | 4 +---
 8 files changed, 8 insertions(+), 17 deletions(-)

diff --git a/x/gov/keeper/keeper.go b/x/gov/keeper/keeper.go
index 0e999d7f2876..60db99d32c11 100644
--- a/x/gov/keeper/keeper.go
+++ b/x/gov/keeper/keeper.go
@@ -68,7 +68,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (keeper Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // Router returns the gov Keeper's Router
diff --git a/x/ibc/applications/transfer/keeper/keeper.go b/x/ibc/applications/transfer/keeper/keeper.go
index e1149ef9be49..a2eebb55e1ea 100644
--- a/x/ibc/applications/transfer/keeper/keeper.go
+++ b/x/ibc/applications/transfer/keeper/keeper.go
@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"fmt"
-
 	tmbytes "github.com/tendermint/tendermint/libs/bytes"
 	"github.com/tendermint/tendermint/libs/log"
 
@@ -63,7 +61,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s-%s", host.ModuleName, types.ModuleName))
+	return ctx.Logger().With("module", "x/"+host.ModuleName+"-"+types.ModuleName)
 }
 
 // GetTransferAccount returns the ICS20 - transfers ModuleAccount
diff --git a/x/ibc/core/02-client/keeper/keeper.go b/x/ibc/core/02-client/keeper/keeper.go
index 18cb4afd68d8..bae7d3627cfe 100644
--- a/x/ibc/core/02-client/keeper/keeper.go
+++ b/x/ibc/core/02-client/keeper/keeper.go
@@ -47,7 +47,7 @@ func NewKeeper(cdc codec.BinaryMarshaler, key sdk.StoreKey, paramSpace paramtype
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s/%s", host.ModuleName, types.SubModuleName))
+	return ctx.Logger().With("module", "x/"+host.ModuleName+"/"+types.SubModuleName)
 }
 
 // GenerateClientIdentifier returns the next client identifier.
diff --git a/x/ibc/core/03-connection/keeper/keeper.go b/x/ibc/core/03-connection/keeper/keeper.go
index 05d110fec809..6637268687c0 100644
--- a/x/ibc/core/03-connection/keeper/keeper.go
+++ b/x/ibc/core/03-connection/keeper/keeper.go
@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"fmt"
-
 	"github.com/tendermint/tendermint/libs/log"
 
 	"github.com/cosmos/cosmos-sdk/codec"
@@ -36,7 +34,7 @@ func NewKeeper(cdc codec.BinaryMarshaler, key sdk.StoreKey, ck types.ClientKeepe
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s/%s", host.ModuleName, types.SubModuleName))
+	return ctx.Logger().With("module", "x/"+host.ModuleName+"/"+types.SubModuleName)
 }
 
 // GetCommitmentPrefix returns the IBC connection store prefix as a commitment
diff --git a/x/ibc/core/04-channel/keeper/keeper.go b/x/ibc/core/04-channel/keeper/keeper.go
index 2390fb41cff5..1651eec5ec87 100644
--- a/x/ibc/core/04-channel/keeper/keeper.go
+++ b/x/ibc/core/04-channel/keeper/keeper.go
@@ -1,7 +1,6 @@
 package keeper
 
 import (
-	"fmt"
 	"strconv"
 	"strings"
 
@@ -52,7 +51,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s/%s", host.ModuleName, types.SubModuleName))
+	return ctx.Logger().With("module", "x/"+host.ModuleName+"/"+types.SubModuleName)
 }
 
 // GenerateChannelIdentifier returns the next channel identifier.
diff --git a/x/ibc/core/05-port/keeper/keeper.go b/x/ibc/core/05-port/keeper/keeper.go
index 5321aeb66a5c..8a4b2300a4e0 100644
--- a/x/ibc/core/05-port/keeper/keeper.go
+++ b/x/ibc/core/05-port/keeper/keeper.go
@@ -26,7 +26,7 @@ func NewKeeper(sck capabilitykeeper.ScopedKeeper) Keeper {
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s/%s", host.ModuleName, types.SubModuleName))
+	return ctx.Logger().With("module", "x/"+host.ModuleName+"/"+types.SubModuleName)
 }
 
 // isBounded checks a given port ID is already bounded.
diff --git a/x/mint/keeper/keeper.go b/x/mint/keeper/keeper.go
index 485ac961b1f1..de0a31222845 100644
--- a/x/mint/keeper/keeper.go
+++ b/x/mint/keeper/keeper.go
@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"fmt"
-
 	"github.com/tendermint/tendermint/libs/log"
 
 	"github.com/cosmos/cosmos-sdk/codec"
@@ -51,7 +49,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // get the minter
diff --git a/x/params/keeper/keeper.go b/x/params/keeper/keeper.go
index a2fdeaa5c0f5..b3d649a2ec49 100644
--- a/x/params/keeper/keeper.go
+++ b/x/params/keeper/keeper.go
@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"fmt"
-
 	"github.com/tendermint/tendermint/libs/log"
 
 	"github.com/cosmos/cosmos-sdk/codec"
@@ -33,7 +31,7 @@ func NewKeeper(cdc codec.BinaryMarshaler, legacyAmino *codec.LegacyAmino, key, t
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", proposal.ModuleName))
+	return ctx.Logger().With("module", "x/"+proposal.ModuleName)
 }
 
 // Allocate subspace used for keepers

From 7c559ec3876aba1d79d53e7a5d1701a8fc514191 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 13:15:08 -0500
Subject: [PATCH 12/14] logging updates

---
 x/slashing/keeper/infractions.go | 30 ++++++++++++++++++++++--------
 x/slashing/keeper/keeper.go      |  2 +-
 x/staking/keeper/keeper.go       |  2 +-
 x/upgrade/keeper/keeper.go       |  3 +--
 4 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/x/slashing/keeper/infractions.go b/x/slashing/keeper/infractions.go
index 168b97b235b9..0c93717d13eb 100644
--- a/x/slashing/keeper/infractions.go
+++ b/x/slashing/keeper/infractions.go
@@ -48,6 +48,8 @@ func (k Keeper) HandleValidatorSignature(ctx sdk.Context, addr cryptotypes.Addre
 		// Array value at this index has not changed, no need to update counter
 	}
 
+	minSignedPerWindow := k.MinSignedPerWindow(ctx)
+
 	if missed {
 		ctx.EventManager().EmitEvent(
 			sdk.NewEvent(
@@ -59,21 +61,22 @@ func (k Keeper) HandleValidatorSignature(ctx sdk.Context, addr cryptotypes.Addre
 		)
 
 		logger.Info(
-			fmt.Sprintf("Absent validator %s at height %d, %d missed, threshold %d", consAddr, height, signInfo.MissedBlocksCounter, k.MinSignedPerWindow(ctx)))
+			"absent validator",
+			"height", height,
+			"validator", consAddr.String(),
+			"missed", signInfo.MissedBlocksCounter,
+			"threshold", minSignedPerWindow,
+		)
 	}
 
 	minHeight := signInfo.StartHeight + k.SignedBlocksWindow(ctx)
-	maxMissed := k.SignedBlocksWindow(ctx) - k.MinSignedPerWindow(ctx)
+	maxMissed := k.SignedBlocksWindow(ctx) - minSignedPerWindow
 
 	// if we are past the minimum height and the validator has missed too many blocks, punish them
 	if height > minHeight && signInfo.MissedBlocksCounter > maxMissed {
 		validator := k.sk.ValidatorByConsAddr(ctx, consAddr)
 		if validator != nil && !validator.IsJailed() {
-
 			// Downtime confirmed: slash and jail the validator
-			logger.Info(fmt.Sprintf("Validator %s past min height of %d and below signed blocks threshold of %d",
-				consAddr, minHeight, k.MinSignedPerWindow(ctx)))
-
 			// We need to retrieve the stake distribution which signed the block, so we subtract ValidatorUpdateDelay from the evidence height,
 			// and subtract an additional 1 since this is the LastCommit.
 			// Note that this *can* result in a negative "distributionHeight" up to -ValidatorUpdateDelay-1,
@@ -99,10 +102,21 @@ func (k Keeper) HandleValidatorSignature(ctx sdk.Context, addr cryptotypes.Addre
 			signInfo.MissedBlocksCounter = 0
 			signInfo.IndexOffset = 0
 			k.clearValidatorMissedBlockBitArray(ctx, consAddr)
+
+			logger.Info(
+				"slashing and jailing validator due to liveness fault",
+				"height", height,
+				"validator", consAddr.String(),
+				"min_height", minHeight,
+				"threshold", minSignedPerWindow,
+				"slashed", k.SlashFractionDowntime(ctx).String(),
+				"jailed_until", signInfo.JailedUntil,
+			)
 		} else {
-			// Validator was (a) not found or (b) already jailed, don't slash
+			// validator was (a) not found or (b) already jailed so we do not slash
 			logger.Info(
-				fmt.Sprintf("Validator %s would have been slashed for downtime, but was either not found in store or already jailed", consAddr),
+				"validator would have been slashed for downtime, but was either not found in store or already jailed",
+				"validator", consAddr.String(),
 			)
 		}
 	}
diff --git a/x/slashing/keeper/keeper.go b/x/slashing/keeper/keeper.go
index b5304a6c5e25..cbed27e9a195 100644
--- a/x/slashing/keeper/keeper.go
+++ b/x/slashing/keeper/keeper.go
@@ -36,7 +36,7 @@ func NewKeeper(cdc codec.BinaryMarshaler, key sdk.StoreKey, sk types.StakingKeep
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // AddPubkey sets a address-pubkey relation
diff --git a/x/staking/keeper/keeper.go b/x/staking/keeper/keeper.go
index 86e32665d11a..74d85a645bf7 100644
--- a/x/staking/keeper/keeper.go
+++ b/x/staking/keeper/keeper.go
@@ -65,7 +65,7 @@ func NewKeeper(
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // Set the validator hooks
diff --git a/x/upgrade/keeper/keeper.go b/x/upgrade/keeper/keeper.go
index 861fd0393a39..05fe6bd0f726 100644
--- a/x/upgrade/keeper/keeper.go
+++ b/x/upgrade/keeper/keeper.go
@@ -3,7 +3,6 @@ package keeper
 import (
 	"encoding/binary"
 	"encoding/json"
-	"fmt"
 	"io/ioutil"
 	"os"
 	"path"
@@ -183,7 +182,7 @@ func (k Keeper) ClearUpgradePlan(ctx sdk.Context) {
 
 // Logger returns a module-specific logger.
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
-	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
+	return ctx.Logger().With("module", "x/"+types.ModuleName)
 }
 
 // GetUpgradePlan returns the currently scheduled Plan if any, setting havePlan to true if there is a scheduled

From 89599016a5cc6a387809b335b908b3c75db1c9e0 Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 13:19:25 -0500
Subject: [PATCH 13/14] logging updates

---
 x/staking/keeper/slash.go | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/x/staking/keeper/slash.go b/x/staking/keeper/slash.go
index 7bef3220f731..a36f6f2e6e20 100644
--- a/x/staking/keeper/slash.go
+++ b/x/staking/keeper/slash.go
@@ -41,10 +41,10 @@ func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeigh
 		// NOTE:  Correctness dependent on invariant that unbonding delegations / redelegations must also have been completely
 		//        slashed in this case - which we don't explicitly check, but should be true.
 		// Log the slash attempt for future reference (maybe we should tag it too)
-		logger.Error(fmt.Sprintf(
-			"WARNING: Ignored attempt to slash a nonexistent validator with address %s, we recommend you investigate immediately",
-			consAddr))
-
+		logger.Error(
+			"WARNING: ignored attempt to slash a nonexistent validator; we recommend you investigate immediately",
+			"validator", consAddr.String(),
+		)
 		return
 	}
 
@@ -71,10 +71,12 @@ func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeigh
 			infractionHeight, ctx.BlockHeight()))
 
 	case infractionHeight == ctx.BlockHeight():
-		// Special-case slash at current height for efficiency - we don't need to look through unbonding delegations or redelegations
-		logger.Info(fmt.Sprintf(
-			"slashing at current height %d, not scanning unbonding delegations & redelegations",
-			infractionHeight))
+		// Special-case slash at current height for efficiency - we don't need to
+		// look through unbonding delegations or redelegations.
+		logger.Info(
+			"slashing at current height; not scanning unbonding delegations & redelegations",
+			"height", infractionHeight,
+		)
 
 	case infractionHeight < ctx.BlockHeight():
 		// Iterate through unbonding delegations from slashed validator
@@ -132,10 +134,12 @@ func (k Keeper) Slash(ctx sdk.Context, consAddr sdk.ConsAddress, infractionHeigh
 		panic("invalid validator status")
 	}
 
-	// Log that a slash occurred!
-	logger.Info(fmt.Sprintf(
-		"validator %s slashed by slash factor of %s; burned %v tokens",
-		validator.GetOperator(), slashFactor.String(), tokensToBurn))
+	logger.Info(
+		"validator slashed by slash factor",
+		"validator", validator.GetOperator().String(),
+		"slash_factor", slashFactor.String(),
+		"burned", tokensToBurn,
+	)
 }
 
 // jail a validator
@@ -143,7 +147,7 @@ func (k Keeper) Jail(ctx sdk.Context, consAddr sdk.ConsAddress) {
 	validator := k.mustGetValidatorByConsAddr(ctx, consAddr)
 	k.jailValidator(ctx, validator)
 	logger := k.Logger(ctx)
-	logger.Info(fmt.Sprintf("validator %s jailed", consAddr))
+	logger.Info("validator jailed", "validator", consAddr)
 }
 
 // unjail a validator
@@ -151,7 +155,7 @@ func (k Keeper) Unjail(ctx sdk.Context, consAddr sdk.ConsAddress) {
 	validator := k.mustGetValidatorByConsAddr(ctx, consAddr)
 	k.unjailValidator(ctx, validator)
 	logger := k.Logger(ctx)
-	logger.Info(fmt.Sprintf("validator %s unjailed", consAddr))
+	logger.Info("validator un-jailed", "validator", consAddr)
 }
 
 // slash an unbonding delegation and update the pool

From daa80b9947cc5d537f7b40ffc38931762c64ffff Mon Sep 17 00:00:00 2001
From: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>
Date: Thu, 3 Dec 2020 13:25:30 -0500
Subject: [PATCH 14/14] cl++

---
 CHANGELOG.md | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d4cf410ec645..5be5c9bddfa0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,6 +37,13 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ## [Unreleased]
 
 ### Improvements
+
+* (logging) [\#8072](https://github.com/cosmos/cosmos-sdk/pull/8072) Refactor logging:
+  * Use [zerolog](https://github.com/rs/zerolog) over Tendermint's go-kit logging wrapper.
+  * Introduce Tendermint's `--log_format=plain|json` flag. Using format `json` allows for emitting structured JSON
+  logs which can be consumed by an external logging facility (e.g. Loggly). Both formats log to STDERR.
+  * The existing `--log_level` flag and it's default value now solely relates to the global logging
+  level (e.g. `info`, `debug`, etc...) instead of `<module>:<level>`.
 * (crypto) [\#7987](https://github.com/cosmos/cosmos-sdk/pull/7987) Fix the inconsistency of CryptoCdc, only use `codec/legacy.Cdc`.
 * (SDK) [\#7925](https://github.com/cosmos/cosmos-sdk/pull/7925) Updated dependencies to use gRPC v1.33.2
   * Updated gRPC dependency to v1.33.2
@@ -44,6 +51,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (version) [\#7848](https://github.com/cosmos/cosmos-sdk/pull/7848) [\#7941](https://github.com/cosmos/cosmos-sdk/pull/7941) `version --long` output now shows the list of build dependencies and replaced build dependencies.
 
 ### State Machine Breaking Changes
+
 * (x/upgrade) [\#7979](https://github.com/cosmos/cosmos-sdk/pull/7979) keeper pubkey storage serialization migration from bech32 to protobuf. 
 
 ### Bug Fixes
@@ -57,6 +65,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/staking) [\#7419](https://github.com/cosmos/cosmos-sdk/pull/7419) The `TmConsPubKey` method on ValidatorI has been removed and replaced instead by `ConsPubKey` (which returns a SDK `cryptotypes.PubKey`) and `TmConsPublicKey` (which returns a Tendermint proto PublicKey).
 
 ### Improvements
+
 * (tendermint) [\#7828](https://github.com/cosmos/cosmos-sdk/pull/7828) Update tendermint dependency to v0.34.0-rc6
 
 ## [v0.40.0-rc2](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.40.0-rc2) - 2020-11-02
@@ -89,18 +98,16 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * __Modules__
   * `x/crisis` has a new function: `AddModuleInitFlags`, which will register optional crisis module flags for the start command.
 
-
 ### Bug Fixes
 
 * (client) [\#7699](https://github.com/cosmos/cosmos-sdk/pull/7699) Fix panic in context when setting invalid nodeURI. `WithNodeURI` does not set the `Client` in the context.
 * (x/gov) [#7641](https://github.com/cosmos/cosmos-sdk/pull/7641) Fix tally calculation precision error.
 
-### Improvements 
+### Improvements
 
 * (rest) [#7649](https://github.com/cosmos/cosmos-sdk/pull/7649) Return an unsigned tx in legacy GET /tx endpoint when signature conversion fails
 * (cli) [#7764](https://github.com/cosmos/cosmos-sdk/pull/7764) Update x/banking and x/crisis InitChain to improve node startup time
 
-
 ## [v0.40.0-rc1](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.40.0-rc1) - 2020-10-19
 
 ### Client Breaking Changes