configure.go

package unikv

import (
	"io/ioutil"
	"os"

	"gopkg.in/yaml.v3"
)

// Configure is unikv's configure structure
type Configure struct {
	Separator  string                          `yaml:"separator" json:"separator"`
	Default    *ConfigureDefault               `yaml:"default" json:"default"`
	Namespaces map[string]*ConfigureNamespaces `yaml:"namespaces" json:"namespaces"`
}

var loadedConfigure bool = false

// GetNamespaceList returns the list of namespaces
func (c *Configure) GetNamespaceList() []string {
	var rslt []string
	for k := range c.Namespaces {
		rslt = append(rslt, k)
	}
	return rslt
}

// GetNamespace returns a specificated namespace from the list
func (c *Configure) GetNamespace(name string) (*ConfigureNamespaces, bool) {
	value, ok := c.Namespaces[name]
	return value, ok
}

// ConfigureDefault is the default segment
// in unikv's configure
type ConfigureDefault struct {
	Driver  string           `yaml:"driver" json:"driver"`
	Context DriverContextRaw `yaml:"context" json:"context"`
}

// ConfigureNamespaces is the namespace segment
// in unikv's configure
type ConfigureNamespaces struct {
	Prefix  string                       `yaml:"prefix" json:"prefix"`
	Buckets map[string]*ConfigureBuckets `yaml:"buckets" json:"buckets"`
}

// GetBucketList returns bucket list
func (c *ConfigureNamespaces) GetBucketList() []string {
	var rslt []string
	for k := range c.Buckets {
		rslt = append(rslt, k)
	}
	return rslt
}

// GetBucket returns the bucket
func (c *ConfigureNamespaces) GetBucket(name string) (*ConfigureBuckets, bool) {
	b, ok := c.Buckets[name]
	return b, ok
}

// ConfigureBuckets is the bucket segment
// in unikv's configure
type ConfigureBuckets struct {
	Prefix  string           `yaml:"prefix" json:"prefix"`
	Driver  string           `yaml:"driver" json:"driver"`
	Context DriverContextRaw `yaml:"context" json:"context"`
}

func determineConfigureFilePath() string {
	rslt, ok := os.LookupEnv(ConfigureEnvName)
	if ok == false {
		rslt = DefaultConfigureFile
	}
	return rslt
}

var configure *Configure

func loadConfigure() {
	content, err := ioutil.ReadFile(determineConfigureFilePath())
	if err != nil {
		panic(err)
	}
	configure = &Configure{
		Separator: PrefixSeparator,
		Default: &ConfigureDefault{
			Driver:  DefaultDriver,
			Context: make(DriverContextRaw),
		},
		Namespaces: make(map[string]*ConfigureNamespaces),
	}
	err = yaml.Unmarshal(content, configure)
	if err != nil {
		panic(err)
	}
	loadedConfigure = true
}

// GetConfigure returns the configure structure
func GetConfigure() *Configure {
	if !loadedConfigure {
		loadConfigure()
	}
	return configure
}

// ReloadConfigure reloads the configure
func ReloadConfigure() {
	loadConfigure()
}