manager.go

// Copyright 2018 The SQLer Authors. All rights reserved.
// Use of this source code is governed by a Apache 2.0
// license that can be found in the LICENSE file.
package main

import (
	"fmt"
	"io/ioutil"
	"path/filepath"
	"strings"
	"text/template"

	"github.com/hashicorp/hcl"
)

// Manager - a macros manager
type Manager struct {
	macros   map[string]*Macro
	compiled *template.Template
}

// NewManager - initialize a new manager
func NewManager(configpath string) (*Manager, error) {
	manager := new(Manager)
	manager.macros = make(map[string]*Macro)
	manager.compiled = template.New("main")

	for _, p := range strings.Split(configpath, ",") {
		files, _ := filepath.Glob(p)

		if len(files) < 1 {
			return nil, fmt.Errorf("invalid path (%s)", p)
		}

		for _, file := range files {
			data, err := ioutil.ReadFile(file)
			if err != nil {
				return nil, err
			}

			var config map[string]*Macro
			if err := hcl.Unmarshal(data, &config); err != nil {
				return nil, err
			}

			for k, v := range config {
				manager.macros[k] = v
				_, err := manager.compiled.New(k).Parse(v.Exec)
				if err != nil {
					return nil, err
				}
				v.manager = manager
				v.name = k
			}
		}
	}

	return manager, nil
}

// Get - fetches the required macro
func (m *Manager) Get(macro string) *Macro {
	return m.macros[macro]
}

// Size - return the size of the currently loaded configs
func (m *Manager) Size() int {
	return len(m.macros)
}

// List - return a list of registered macros
func (m *Manager) List() (ret []string) {
	for k := range m.macros {
		ret = append(ret, k)
	}

	return ret
}