From 9100680162da8c44b85750ec8c72ec93131c3109 Mon Sep 17 00:00:00 2001
From: Pieter Noordhuis <pieter.noordhuis@databricks.com>
Date: Tue, 21 Mar 2023 17:05:04 +0100
Subject: [PATCH] Allow logger defaults to be configured through environment
 variables (#266)

These environment variables configure defaults for the logger related
flags:
* `BRICKS_LOG_FILE`
* `BRICKS_LOG_LEVEL`
* `BRICKS_LOG_FORMAT`
---
 cmd/root/logger.go | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/cmd/root/logger.go b/cmd/root/logger.go
index ebe65f60..29e75ed4 100644
--- a/cmd/root/logger.go
+++ b/cmd/root/logger.go
@@ -3,6 +3,7 @@ package root
 import (
 	"context"
 	"fmt"
+	"os"
 
 	"github.com/databricks/bricks/libs/flags"
 	"github.com/databricks/bricks/libs/log"
@@ -10,6 +11,12 @@ import (
 	"golang.org/x/exp/slog"
 )
 
+const (
+	envBricksLogFile   = "BRICKS_LOG_FILE"
+	envBricksLogLevel  = "BRICKS_LOG_LEVEL"
+	envBricksLogFormat = "BRICKS_LOG_FORMAT"
+)
+
 func initializeLogger(ctx context.Context, cmd *cobra.Command) (context.Context, error) {
 	opts := slog.HandlerOptions{}
 	opts.Level = logLevel.Level()
@@ -41,6 +48,18 @@ var logLevel = flags.NewLogLevelFlag()
 var logOutput = flags.OutputText
 
 func init() {
+	// Configure defaults from environment, if applicable.
+	// If the provided value is invalid it is ignored.
+	if v, ok := os.LookupEnv(envBricksLogFile); ok {
+		logFile.Set(v)
+	}
+	if v, ok := os.LookupEnv(envBricksLogLevel); ok {
+		logLevel.Set(v)
+	}
+	if v, ok := os.LookupEnv(envBricksLogFormat); ok {
+		logOutput.Set(v)
+	}
+
 	RootCmd.PersistentFlags().Var(&logFile, "log-file", "file to write logs to")
 	RootCmd.PersistentFlags().Var(&logLevel, "log-level", "log level")
 	RootCmd.PersistentFlags().Var(&logOutput, "log-format", "log output format (text or json)")