MikkelHJuul/ld

package impl

import (
    "context"
    "io"

    pb "github.com/MikkelHJuul/ld/proto"
    "github.com/dgraph-io/badger/v3"
    log "github.com/sirupsen/logrus"
)

// Set implements method Set from proto.LdServer. returns nothing for succes, the value and error for any error.
func (l ldService) Set(_ context.Context, value *pb.KeyValue) (*pb.KeyValue, error) {
    err := l.DB.Update(func(txn *badger.Txn) error {
        return txn.Set(value.Key, value.Value)
    })
    if err != nil {
        log.Errorf("error while saving data to database: %v ", err)
        return value, err
    }
    return &pb.KeyValue{}, nil
}

// SetMany implements method SetMany from proto.LdServer.
func (l ldService) SetMany(server pb.Ld_SetManyServer) error {
    in := make(chan *pb.KeyValue)
    ctx, ccl := context.WithCancel(context.Background())
    out := l.setManyGenerator(in)
    go sendCancel(server, out, ccl)
    for {
        create, err := server.Recv()
        if err == io.EOF {
            close(in)
            break
        }
        if err != nil {
            return err
        }
        in <- create
    }
    <-ctx.Done()
    return nil
}

func (l ldService) setManyGenerator(in chan *pb.KeyValue) chan *pb.KeyValue {
    out := make(chan *pb.KeyValue)
    go func() {
        txn := l.DB.NewTransaction(true)
        for create := range in {
            err := l.handleKeyTransaction(txn, &pb.Key{Key: create.Key}, true, func(txn *badger.Txn, key *pb.Key) error {
                return txn.Set(create.Key, create.Value)
            })
            if err != nil {
                out <- create
            } else {
                out <- &pb.KeyValue{}
            }
        }
        close(out)
        if err := txn.Commit(); err != nil {
            log.Warn("error when committing transaction in goroutine", err) //probably not?
        }
    }()
    return out
}