config.go

// BSD 3-Clause License

// Copyright (c) 2021, Michael Grigoryan
// All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:

// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.

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//    this list of conditions and the following disclaimer in the documentation
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//    this software without specific prior written permission.

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package hydra

import (
	"os"
	"path/filepath"
)

// hydra.Config is the configuration struct which is going to be
// used by Hydra for initialization.
type Config struct {
	Paths []string
}

// This function will attempt to get the first usable and correct
// path where the configuration has been specified. Will return an
// error if something goes wrong.
func (c *Config) findConfigPath() (string, error) {
	// In this part, we are looping through all the provided
	// configuration Paths, in search of the first valid path.
	for _, path := range c.Paths {
		path = filepath.Clean(path) // cleaning the path from various redundancies.
		dir, file := filepath.Split(path)

		// Scanning all the files in all the directories provided by
		// the user, and checking file/folder entries.
		if entries, err := os.ReadDir(dir); err == nil {
			for _, i := range entries {
				// Since we only need files and not folders, we can break the loop
				// from here and move forward.
				if i.Type().IsRegular() && i.Name() == file {
					return path, nil
				}
			}
		}
	}

	// If nothing was matched, or the user did not provide any
	// search paths, defaulting to an empty string and moving on
	// to parsing the environment variables.
	return "", nil
}