tendermint/grpcdb/example_test.go
Emmanuel T Odeke 11bee6194a
DB as a service
Fixes https://github.com/tendermint/tendermint/issues/1162

Databases as a service!

Can now access Databases as a remote service
via gRPC for performance and easy deployment.

The caveat is that each service is stateful in regards to
the DB i.e. each unique service uses only one unique DB
but nonetheless multiple clients can access it.

A full standalone example

```go
package main

import (
  "bytes"
  "context"
  "log"

  grpcdb "github.com/tendermint/tmlibs/grpcdb"
  protodb "github.com/tendermint/tmlibs/proto"
)

func main() {
  addr := ":8998"
  go func() {
    if err := grpcdb.BindRemoteDBServer(addr); err != nil {
      log.Fatalf("BindRemoteDBServer: %v", err)
    }
  }()

  client, err := grpcdb.NewClient(addr, false)
  if err != nil {
    log.Fatalf("Failed to create grpcDB client: %v", err)
  }

  ctx := context.Background()
  // 1. Initialize the DB
  in := &protodb.Init{
    Type: "leveldb",
    Name: "grpc-uno-test",
    Dir:  ".",
  }
  if _, err := client.Init(ctx, in); err != nil {
    log.Fatalf("Init error: %v", err)
  }

  // 2. Now it can be used!
  query1 := &protodb.Entity{Key: []byte("Project"), Value:
[]byte("Tmlibs-on-gRPC")}
  if _, err := client.SetSync(ctx, query1); err != nil {
    log.Fatalf("SetSync err: %v", err)
  }

  query2 := &protodb.Entity{Key: []byte("Project")}
  read, err := client.Get(ctx, query2)
  if err != nil {
    log.Fatalf("Get err: %v", err)
  }
  if g, w := read.Value, []byte("Tmlibs-on-gRPC"); !bytes.Equal(g, w) {
    log.Fatalf("got= (%q ==> % X)\nwant=(%q ==> % X)", g, g, w, w)
  }
}
```
2018-05-07 22:00:33 +02:00

51 lines
1.1 KiB
Go

package grpcdb_test
import (
"bytes"
"context"
"log"
grpcdb "github.com/tendermint/tmlibs/grpcdb"
protodb "github.com/tendermint/tmlibs/proto"
)
func Example() {
addr := ":8998"
go func() {
if err := grpcdb.BindRemoteDBServer(addr); err != nil {
log.Fatalf("BindRemoteDBServer: %v", err)
}
}()
client, err := grpcdb.NewClient(addr, false)
if err != nil {
log.Fatalf("Failed to create grpcDB client: %v", err)
}
ctx := context.Background()
// 1. Initialize the DB
in := &protodb.Init{
Type: "leveldb",
Name: "grpc-uno-test",
Dir: ".",
}
if _, err := client.Init(ctx, in); err != nil {
log.Fatalf("Init error: %v", err)
}
// 2. Now it can be used!
query1 := &protodb.Entity{Key: []byte("Project"), Value: []byte("Tmlibs-on-gRPC")}
if _, err := client.SetSync(ctx, query1); err != nil {
log.Fatalf("SetSync err: %v", err)
}
query2 := &protodb.Entity{Key: []byte("Project")}
read, err := client.Get(ctx, query2)
if err != nil {
log.Fatalf("Get err: %v", err)
}
if g, w := read.Value, []byte("Tmlibs-on-gRPC"); !bytes.Equal(g, w) {
log.Fatalf("got= (%q ==> % X)\nwant=(%q ==> % X)", g, g, w, w)
}
}