readme

README.md

@@ -2,5 +2,5 @@
 
 Given source DB,
 
-   1. fully sync to local db
-   1. continuously sync to local db
+   1. fully sync from src to dest db
+   1. continuously sync from src to dest db

go.mod

@@ -1,3 +1,5 @@
 module replicator
 
 go 1.21.1
+
+require gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -0,0 +1,3 @@
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -2,16 +2,67 @@ package main
 
 import (
 	"context"
+	"flag"
+	"net/url"
+	"os"
 	"os/signal"
 	"replicator/replicator"
 	"syscall"
+	"time"
+
+	"gopkg.in/yaml.v3"
 )
 
 func main() {
 	ctx, can := signal.NotifyContext(context.Background(), syscall.SIGINT)
 	defer can()
 
-	if err := replicator.Main(ctx); err != nil && ctx.Err() == nil {
+	config, err := getConfig()
+	if err != nil {
+		panic(err)
+	}
+
+	if err := replicator.Main(ctx, config); err != nil && ctx.Err() == nil {
 		panic(err)
 	}
 }
+
+func getConfig() (replicator.Config, error) {
+	var config replicator.Config
+	if p := os.Getenv("CONFIG"); p != "" {
+		f, err := os.Open(p)
+		if err != nil {
+			return config, err
+		}
+		defer f.Close()
+		if err := yaml.NewDecoder(f).Decode(&config); err != nil {
+			return config, err
+		}
+	}
+
+	var srcDriver, destDriver, interval string
+	flag.StringVar(&srcDriver, "src", "map://", "source db")
+	flag.StringVar(&destDriver, "dest", "map://", "dest db")
+	flag.StringVar(&interval, "interval", "1s", "interval")
+	flag.Parse()
+
+	if srcDriver, err := url.Parse(srcDriver); err != nil {
+		return config, err
+	} else {
+		config.Src.Driver = *srcDriver
+	}
+
+	if destDriver, err := url.Parse(destDriver); err != nil {
+		return config, err
+	} else {
+		config.Dest.Driver = *destDriver
+	}
+
+	if interval, err := time.ParseDuration(interval); err != nil {
+		return config, err
+	} else {
+		config.Interval = replicator.Duration(interval)
+	}
+
+	return config, nil
+}

replicator/config.go

@@ -1,20 +1,53 @@
 package replicator
 
-import "net/url"
+import (
+	"encoding/json"
+	"net/url"
+	"time"
+
+	"gopkg.in/yaml.v3"
+)
 
 type (
 	Config struct {
-		Local  Storage
-		Remote Storage
+		Src      Storage
+		Dest     Storage
+		Interval Duration
 	}
 
 	Storage struct {
-		Driver      url.URL
-		Full        Stream
-		Incremental Stream
+		Driver url.URL
 	}
 
-	Stream struct {
-		Disabled bool
-	}
+	Duration time.Duration
 )
+
+func (d *Duration) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	d2, err := time.ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = Duration(d2)
+	return nil
+}
+
+func (d Duration) MarshalJSON() ([]byte, error) {
+	return json.Marshal(time.Duration(d).String())
+}
+
+func (d *Duration) UnmarshalYAML(value *yaml.Node) error {
+	var s string
+	if err := value.Decode(&s); err != nil {
+		return err
+	}
+	b, _ := json.Marshal(s)
+	return d.UnmarshalJSON(b)
+}
+
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return time.Duration(d).String(), nil
+}

replicator/config_test.go

@@ -0,0 +1,30 @@
+package replicator
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"gopkg.in/yaml.v3"
+)
+
+func TestDuration(t *testing.T) {
+	d := Duration(3*time.Second + time.Minute)
+	var d2 Duration
+	if b, err := json.Marshal(d); err != nil {
+		t.Fatal(err)
+	} else if err := json.Unmarshal(b, &d2); err != nil {
+		t.Fatal(err)
+	} else if d != d2 {
+		t.Fatal(d, d2)
+	}
+
+	var d3 Duration
+	if b, err := yaml.Marshal(d); err != nil {
+		t.Fatal(err)
+	} else if err := yaml.Unmarshal(b, &d3); err != nil {
+		t.Fatal(err)
+	} else if d != d3 {
+		t.Fatal(d, d3)
+	}
+}

replicator/main.go

@@ -2,9 +2,19 @@ package replicator
 
 import (
 	"context"
-	"errors"
 )
 
-func Main(ctx context.Context) error {
-	return errors.New("not impl")
+func Main(ctx context.Context, config Config) error {
+	src, err := NewDriver(ctx, config.Src.Driver)
+	if err != nil {
+		return err
+	}
+
+	dest, err := NewDriver(ctx, config.Dest.Driver)
+	if err != nil {
+		return err
+	}
+
+	replicator := NewReplicator(dest, src)
+	return replicator.Stream(ctx)
 }

replicator/replicator.go

@@ -11,7 +11,7 @@ type Replicator struct {
 	Interval time.Duration
 }
 
-func NewReplicator(src, dest Driver) Replicator {
+func NewReplicator(dest, src Driver) Replicator {
 	return Replicator{
 		Src:      src,
 		Dest:     dest,