feat(log): add warn log level (#18898)

Co-authored-by: marbar3778 <[email protected]>

log/CHANGELOG.md

@@ -24,6 +24,7 @@ Each entry must include the Github issue reference in the following format:
 
 * [#18916](https://github.com/cosmos/cosmos-sdk/pull/18916) Introduce an option for setting hooks.
 * [#18429](https://github.com/cosmos/cosmos-sdk/pull/18429) Support customization of log json marshal.
+* [#18898](https://github.com/cosmos/cosmos-sdk/pull/18898) Add `WARN` level. 
 
 ## [v1.2.1](https://github.com/cosmos/cosmos-sdk/releases/tag/log/v1.2.1) - 2023-08-25
 

log/logger.go

@@ -40,6 +40,10 @@ type Logger interface {
 	// The key of the tuple must be a string.
 	Info(msg string, keyVals ...any)
 
+	// Warn takes a message and a set of key/value pairs and logs with level WARN.
+	// The key of the tuple must be a string.
+	Warn(msg string, keyVals ...any)
+
 	// Error takes a message and a set of key/value pairs and logs with level ERR.
 	// The key of the tuple must be a string.
 	Error(msg string, keyVals ...any)
@@ -140,6 +144,12 @@ func (l zeroLogWrapper) Info(msg string, keyVals ...interface{}) {
 	l.Logger.Info().Fields(keyVals).Msg(msg)
 }
 
+// Info takes a message and a set of key/value pairs and logs with level INFO.
+// The key of the tuple must be a string.
+func (l zeroLogWrapper) Warn(msg string, keyVals ...interface{}) {
+	l.Logger.Warn().Fields(keyVals).Msg(msg)
+}
+
 // Error takes a message and a set of key/value pairs and logs with level DEBUG.
 // The key of the tuple must be a string.
 func (l zeroLogWrapper) Error(msg string, keyVals ...interface{}) {
@@ -176,6 +186,7 @@ func NewNopLogger() Logger {
 type nopLogger struct{}
 
 func (nopLogger) Info(string, ...any)  {}
+func (nopLogger) Warn(string, ...any)  {}
 func (nopLogger) Error(string, ...any) {}
 func (nopLogger) Debug(string, ...any) {}
 func (nopLogger) With(...any) Logger   { return nopLogger{} }