chore(config): simplify configuration flags

Drop config.dir and use config.file to pass full path to the config file. Passing two options is just an unnecessary complexity
Fixes #22.

demo/supervisord.conf

@@ -23,7 +23,7 @@ stderr_logfile=/dev/stderr
 stderr_logfile_maxbytes=0
 
 [program:karma]
-command=/karma --config.dir /etc/
+command=/karma --config.file /etc/karma.yaml
 autorestart=true
 stdout_logfile=/dev/stdout
 stdout_logfile_maxbytes=0

docs/CONFIGURATION.md

@@ -8,22 +8,15 @@ it needs to have `.yaml` extension.
 Custom filename and directory can be passed via command line flags or
 environment variables:
 
-- `--config.file` flag or `CONFIG_FILE` env variable - name of the config file
-  to load (without extension).
-- `--config.dir` flag or `CONFIG_DIR` env variable - directory where config file
-  can be found.
+- `--config.file` flag or `CONFIG_FILE` env variable - path to the config file
 
 Example with flags:
 
-    karma --config.file example --config.dir ./docs/
+    karma --config.file docs/example.yaml
 
 Example with environment variables:
 
-    CONFIG_FILE="example" CONFIG_DIR="./docs/" karma
-
-Example using both:
-
-    CONFIG_FILE="example" karma --config.dir ./docs/
+    CONFIG_FILE="docs/example.yaml"
 
 ### Alertmanagers
 

internal/config/config.go

@@ -3,7 +3,6 @@ package config
 import (
 	"bufio"
 	"bytes"
-	"path"
 	"strings"
 	"time"
 
@@ -40,10 +39,7 @@ func init() {
 	pflag.StringSlice("annotations.visible", []string{},
 		"List of annotations that are visible by default")
 
-	pflag.String("config.dir", ".",
-		"Directory with configuration file to read")
-	pflag.String("config.file", "karma",
-		"Name of the configuration file to read")
+	pflag.String("config.path", "", "Full path to the configuration file")
 
 	pflag.Bool("debug", false, "Enable debug mode")
 
@@ -105,21 +101,18 @@ func (config *configSchema) Read() {
 		log.Errorf("Failed to bind sentry.private config key to the SENTRY_DSN env variable: %s", err)
 	}
 
-	configFile := v.GetString("config.file")
-	configDir := v.GetString("config.dir")
 	v.SetConfigType("yaml")
-	v.SetConfigName(configFile)
-	v.AddConfigPath(configDir)
-	log.Infof("Reading configuration file %s.yaml", path.Join(configDir, configFile))
+	configPath := v.GetString("config.path")
+	if configPath != "" {
+		log.Infof("Reading configuration file %s", configPath)
+		v.SetConfigFile(configPath)
+	}
+
 	err = v.ReadInConfig()
 	if v.ConfigFileUsed() != "" && err != nil {
 		log.Fatal(err)
 	}
 
-	if v.ConfigFileUsed() != "" {
-		log.Infof("Config file used: %s", v.ConfigFileUsed())
-	}
-
 	config.Alertmanager.Servers = []alertmanagerConfig{}
 	config.Alertmanager.Interval = v.GetDuration("alertmanager.interval")
 	config.Annotations.Default.Hidden = v.GetBool("annotations.default.hidden")

internal/config/config_test.go

@@ -24,7 +24,6 @@ func resetEnv() {
 		"ANNOTATIONS_DEFAULT_HIDDEN",
 		"ANNOTATIONS_HIDDEN",
 		"ANNOTATIONS_VISIBLE",
-		"CONFIG_DIR",
 		"CONFIG_FILE",
 		"DEBUG",
 		"FILTERS_DEFAULT",