62 lines
1.2 KiB
Go
62 lines
1.2 KiB
Go
package server
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import (
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"database/sql"
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"time"
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_ "github.com/mattn/go-sqlite3" // SQLite driver
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)
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const (
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createTableQuery = `CREATE TABLE IF NOT EXISTS messages (
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id VARCHAR(20) PRIMARY KEY,
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time INT NOT NULL,
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topic VARCHAR(64) NOT NULL,
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message VARCHAR(1024) NOT NULL
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)`
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insertQuery = `INSERT INTO messages (id, time, topic, message) VALUES (?, ?, ?, ?)`
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pruneOlderThanQuery = `DELETE FROM messages WHERE time < ?`
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)
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type cache struct {
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db *sql.DB
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insert *sql.Stmt
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prune *sql.Stmt
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}
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func newCache(filename string) (*cache, error) {
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db, err := sql.Open("sqlite3", filename)
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if err != nil {
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return nil, err
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}
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if _, err := db.Exec(createTableQuery); err != nil {
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return nil, err
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}
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insert, err := db.Prepare(insertQuery)
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if err != nil {
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return nil, err
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}
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prune, err := db.Prepare(pruneOlderThanQuery)
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if err != nil {
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return nil, err
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}
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return &cache{
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db: db,
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insert: insert,
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prune: prune,
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}, nil
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}
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func (c *cache) Load() (map[string]*topic, error) {
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}
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func (c *cache) Add(m *message) error {
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_, err := c.insert.Exec(m.ID, m.Time, m.Topic, m.Message)
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return err
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}
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func (c *cache) Prune(olderThan time.Duration) error {
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_, err := c.prune.Exec(time.Now().Add(-1 * olderThan).Unix())
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return err
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}
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