spoc-bot-vr/persistence.go

48 lines
1.2 KiB
Go

package main
import (
"context"
"fmt"
)
type MessageToPersistence struct {
pipeline Pipeline
}
func NewMessageToPersistencePipeline(ctx context.Context, cfg Config) (Pipeline, error) {
reader, err := NewQueue(ctx, "new_message", cfg.driver)
if err != nil {
return Pipeline{}, err
}
writer, err := NewQueue(ctx, "new_persistence", cfg.driver)
if err != nil {
return Pipeline{}, err
}
return Pipeline{
writer: writer,
reader: reader,
process: newMessageToPersistenceProcess(cfg.driver),
}, nil
}
func newMessageToPersistenceProcess(driver Driver) processFunc {
return func(ctx context.Context, msg []byte) ([]byte, error) {
m, err := Deserialize(msg)
if err != nil {
return nil, err
}
if result, err := driver.ExecContext(ctx, `
CREATE TABLE IF NOT EXISTS messages (id TEXT UNIQUE, v TEXT);
INSERT INTO messages (id, v) VALUES (?, ?)
ON CONFLICT(id) DO UPDATE set v = ?;
`, m.ID, msg, msg); err != nil {
return nil, err
} else if n, err := result.RowsAffected(); err != nil {
return nil, err
} else if n != 1 {
return nil, fmt.Errorf("upserting event to persistence modified %v rows", n)
}
return msg, nil
}
}