move client_configuration_finder to client_configuration

client_configuration.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"path"
 	"strings"
 )
 
@@ -20,6 +21,68 @@ const (
 	levelTrace string = "TRACE" // trace log level
 )
 
+const (
+	defaultConfigName = "sf_client_config.json"
+	clientConfEnvName = "SF_CLIENT_CONFIG_FILE"
+)
+
+func getClientConfig(filePathFromConnectionString string) (*ClientConfig, error) {
+	configPredefinedFilePaths, err := clientConfigPredefinedDirs()
+	var filePath string
+	filePath, err = findClientConfigFilePath(filePathFromConnectionString, configPredefinedFilePaths)
+	if err != nil {
+		return nil, err
+	}
+	if filePath == "" { // we did not find a config file
+		return nil, nil
+	}
+	return parseClientConfiguration(filePath)
+}
+
+func findClientConfigFilePath(filePathFromConnectionString string, configPredefinedDirs []string) (string, error) {
+	if filePathFromConnectionString != "" {
+		return filePathFromConnectionString, nil
+	}
+	envConfigFilePath := os.Getenv(clientConfEnvName)
+	if envConfigFilePath != "" {
+		return envConfigFilePath, nil
+	}
+	return searchForConfigFile(configPredefinedDirs)
+}
+
+func searchForConfigFile(directories []string) (string, error) {
+	for _, dir := range directories {
+		filePath := path.Join(dir, defaultConfigName)
+		exists, err := existsFile(filePath)
+		if err != nil {
+			return "", err
+		}
+		if exists {
+			return filePath, nil
+		}
+	}
+	return "", nil
+}
+
+func existsFile(filePath string) (bool, error) {
+	_, err := os.Stat(filePath)
+	if err == nil {
+		return true, nil
+	}
+	if errors.Is(err, os.ErrNotExist) {
+		return false, nil
+	}
+	return false, err
+}
+
+func clientConfigPredefinedDirs() ([]string, error) {
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		return nil, err
+	}
+	return []string{".", homeDir, os.TempDir()}, nil
+}
+
 // ClientConfig config root
 type ClientConfig struct {
 	Common *ClientConfigCommonProps `json:"common"`