micro-config-file/file.go
Vasiliy Tolstov 369a16afd9 update to micro v3.1.2
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2021-01-19 03:16:37 +03:00

117 lines
2.2 KiB
Go

package file
import (
"context"
"errors"
"fmt"
"io"
"io/ioutil"
"os"
"github.com/imdario/mergo"
"github.com/unistack-org/micro/v3/codec"
"github.com/unistack-org/micro/v3/config"
rutil "github.com/unistack-org/micro/v3/util/reflect"
)
var (
DefaultStructTag = "file"
ErrPathNotExist = errors.New("path is not exist")
)
type fileConfig struct {
opts config.Options
path string
}
func (c *fileConfig) Options() config.Options {
return c.opts
}
func (c *fileConfig) Init(opts ...config.Option) error {
for _, o := range opts {
o(&c.opts)
}
path := ""
if c.opts.Context != nil {
if v, ok := c.opts.Context.Value(pathKey{}).(string); ok {
path = v
}
}
if path == "" {
return ErrPathNotExist
}
c.path = path
return nil
}
func (c *fileConfig) Load(ctx context.Context) error {
for _, fn := range c.opts.BeforeLoad {
if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
return err
}
}
fp, err := os.OpenFile(c.path, os.O_RDONLY, os.FileMode(0400))
if err != nil && !c.opts.AllowFail {
return fmt.Errorf("failed to open: %s, error: %w", c.path, ErrPathNotExist)
} else if err == nil {
defer fp.Close()
var buf []byte
buf, err = ioutil.ReadAll(io.LimitReader(fp, int64(codec.DefaultMaxMsgSize)))
if err == nil {
src, err := rutil.Zero(c.opts.Struct)
if err == nil {
err = c.opts.Codec.Unmarshal(buf, src)
if err == nil {
err = mergo.Merge(c.opts.Struct, src, mergo.WithOverride, mergo.WithTypeCheck, mergo.WithAppendSlice)
}
}
}
if err != nil && !c.opts.AllowFail {
return err
}
}
for _, fn := range c.opts.AfterLoad {
if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
return err
}
}
return nil
}
func (c *fileConfig) Save(ctx context.Context) error {
for _, fn := range c.opts.BeforeSave {
if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
return err
}
}
for _, fn := range c.opts.AfterSave {
if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
return err
}
}
return nil
}
func (c *fileConfig) String() string {
return "file"
}
func NewConfig(opts ...config.Option) config.Config {
options := config.NewOptions(opts...)
if len(options.StructTag) == 0 {
options.StructTag = DefaultStructTag
}
return &fileConfig{opts: options}
}