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Upgraded to pgx

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This commit is contained in:
Magnus Åhall 2025-09-23 21:47:39 +02:00
parent 825cf0fc9a
commit ad601219ec
3 changed files with 66 additions and 49 deletions
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9
database.go
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@ -1,8 +1,11 @@
package dbschema
import (
// External
"github.com/jackc/pgx/v5/pgxpool"
// Standard
"database/sql"
"context"
"fmt"
)
@ -13,10 +16,10 @@ func newDatabase(host string, port int, dbName, user, pass string) (dbase Databa
dbase.Username = user
dbase.Password = pass
dbase.db, err = sql.Open("postgres", dbase.sqlConnString())
dbase.db, err = pgxpool.New(context.Background(), dbase.sqlConnString())
return
}// }}}
func databaseFromInstance(db *sql.DB) (dbase Database, err error) {
func databaseFromInstance(db *pgxpool.Pool) (dbase Database, err error) {
dbase.db = db
return
}

7
schema.go
View file

@ -21,10 +21,7 @@ package dbschema
import (
// External
_ "github.com/lib/pq"
// Standard
"database/sql"
"github.com/jackc/pgx/v5/pgxpool"
)
// An upgrader verifies the schema for one or more databases and upgrades them if possible.
@ -42,7 +39,7 @@ type Database struct {
Username string
Password string
db *sql.DB
db *pgxpool.Pool
upgrader *Upgrader
}

99
upgrader.go
View file

@ -2,19 +2,22 @@ package dbschema
import (
// External
"github.com/lib/pq"
"github.com/jackc/pgx/v5"
"github.com/jackc/pgx/v5/pgconn"
"github.com/jackc/pgx/v5/pgxpool"
// Standard
"context"
"database/sql"
"fmt"
)
func defaultCallback(topic, msg string) {// {{{
func defaultCallback(topic, msg string) { // {{{
fmt.Printf("[%s] %s\n", topic, msg)
}// }}}
} // }}}
// NewUpgrader creates an upgrader with an empty list of databases.
func NewUpgrader(schema ...string) (upgrader Upgrader) {// {{{
func NewUpgrader(schema ...string) (upgrader Upgrader) { // {{{
// Using a variadic function for backward compatibility.
if len(schema) > 0 {
upgrader.schema = schema[0]
@ -25,18 +28,18 @@ func NewUpgrader(schema ...string) (upgrader Upgrader) {// {{{
upgrader.logCallback = defaultCallback
upgrader.databases = map[string]Database{}
return
}// }}}
} // }}}
// SetLogCallback allows to set a callback for custom logging.
func (upgrader *Upgrader) SetLogCallback(callback func(string, string)) {// {{{
func (upgrader *Upgrader) SetLogCallback(callback func(string, string)) { // {{{
upgrader.logCallback = callback
}// }}}
} // }}}
// SetSqlCallback is required for providing the SQL schema updates.
func (upgrader *Upgrader) SetSqlCallback(callback func(string, int) ([]byte, bool)) {// {{{
func (upgrader *Upgrader) SetSqlCallback(callback func(string, int) ([]byte, bool)) { // {{{
upgrader.sqlCallback = callback
}// }}}
} // }}}
// Version returns the current dbschema version for the given database name.
func (upgrader *Upgrader) Version(dbName string) (version int, err error) {// {{{
func (upgrader *Upgrader) Version(dbName string) (version int, err error) { // {{{
dbase, found := upgrader.databases[dbName]
if !found {
err = fmt.Errorf("Database %s not previously added to the upgrader", dbName)
@ -45,21 +48,22 @@ func (upgrader *Upgrader) Version(dbName string) (version int, err error) {// {{
version, err = dbase.Version()
return
}// }}}
} // }}}
func (dbase Database) createSchemaTable() (err error) {// {{{
func (dbase Database) createSchemaTable() (err error) { // {{{
dbase.upgrader.logCallback("create", fmt.Sprintf("%s, %s.schema", dbase.DbName, dbase.upgrader.schema))
_, err = dbase.db.Exec(`CREATE SCHEMA "`+dbase.upgrader.schema+`"`)
_, err = dbase.db.Exec(context.Background(), `CREATE SCHEMA "` + dbase.upgrader.schema + `"`)
// Error code 42P06 "duplicate_schema" is an OK error,
// table can still be missing and created.
pqErr, _ := err.(*pq.Error)
pqErr, _ := err.(*pgconn.PgError)
if pqErr != nil && pqErr.Code != "42P06" {
return
}
_, err = dbase.db.Exec(`
CREATE TABLE "`+dbase.upgrader.schema+`"."schema" (
_, err = dbase.db.Exec(
context.Background(),
`CREATE TABLE "` + dbase.upgrader.schema + `"."schema" (
version int4 NOT NULL,
updated timestamp NOT NULL DEFAULT NOW(),
@ -67,19 +71,20 @@ func (dbase Database) createSchemaTable() (err error) {// {{{
)`,
)
return
}// }}}
func (dbase Database) appendSchemaVersion(version int) (err error) {// {{{
_, err = dbase.db.Exec(`INSERT INTO `+dbase.upgrader.schema+`.schema(version) VALUES($1)`, version)
} // }}}
func (dbase Database) appendSchemaVersion(version int) (err error) { // {{{
_, err = dbase.db.Exec(context.Background(), `INSERT INTO `+dbase.upgrader.schema+`.schema(version) VALUES($1)`, version)
return
}// }}}
} // }}}
func (dbase Database) verifySchemaTable() (err error) {// {{{
var rows *sql.Rows
func (dbase Database) verifySchemaTable() (err error) { // {{{
var rows pgx.Rows
if rows, err = dbase.db.Query(
context.Background(),
`SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE n.nspname = '`+dbase.upgrader.schema+`'
WHERE n.nspname = '` + dbase.upgrader.schema + `'
AND c.relname = 'schema'
)`,
); err != nil {
@ -97,11 +102,11 @@ func (dbase Database) verifySchemaTable() (err error) {// {{{
}
err = dbase.createSchemaTable()
return
}// }}}
func (dbase Database) verifySchemaEntry() (err error) {// {{{
} // }}}
func (dbase Database) verifySchemaEntry() (err error) { // {{{
var version int
var row *sql.Row
row = dbase.db.QueryRow(`SELECT version FROM `+dbase.upgrader.schema+`.schema LIMIT 1`)
var row pgx.Row
row = dbase.db.QueryRow(context.Background(), `SELECT version FROM `+dbase.upgrader.schema+`.schema LIMIT 1`)
err = row.Scan(&version)
if err == sql.ErrNoRows {
@ -110,11 +115,12 @@ func (dbase Database) verifySchemaEntry() (err error) {// {{{
}
return
}// }}}
func (dbase Database) Version() (version int, err error) {// {{{
var rows *sql.Rows
} // }}}
func (dbase Database) Version() (version int, err error) { // {{{
var rows pgx.Rows
rows, err = dbase.db.Query(
`SELECT version FROM `+dbase.upgrader.schema+`.schema ORDER BY version DESC LIMIT 1`,
context.Background(),
`SELECT version FROM ` + dbase.upgrader.schema + `.schema ORDER BY version DESC LIMIT 1`,
)
if err != nil {
return
@ -127,15 +133,15 @@ func (dbase Database) Version() (version int, err error) {// {{{
err = fmt.Errorf(`Database "%s" is missing an entry in `+dbase.upgrader.schema+`.schema`, dbase.DbName)
}
return
}// }}}
} // }}}
// AddDatabase sets a database up for the Run() function with verifying/creating the _db.schema table.
func (upgrader Upgrader) AddDatabase(host string, port int, dbName, user, pass string) (db Database, err error) {// {{{
func (upgrader Upgrader) AddDatabase(host string, port int, dbName, user, pass string) (db Database, err error) { // {{{
if db, err = newDatabase(host, port, dbName, user, pass); err != nil {
return
}
db.upgrader = &upgrader
upgrader.databases[dbName] = db
if err = db.verifySchemaTable(); err != nil {
@ -144,13 +150,24 @@ func (upgrader Upgrader) AddDatabase(host string, port int, dbName, user, pass s
err = db.verifySchemaEntry()
return
}// }}}
func (upgrader Upgrader) AddDatabaseInstance(sqlDB *sql.DB) (db Database, err error) {// {{{
return databaseFromInstance(sqlDB)
}// }}}
} // }}}
func (upgrader Upgrader) AddDatabaseInstance(sqlDB *pgxpool.Pool, dbName string) (db Database, err error) { // {{{
db, err = databaseFromInstance(sqlDB)
db.upgrader = &upgrader
upgrader.databases[dbName] = db
if err = db.verifySchemaTable(); err != nil {
return
}
err = db.verifySchemaEntry()
return
} // }}}
// Run executes the actual schema updates until there are no more available.
func (upgrader Upgrader) Run() (err error) {// {{{
func (upgrader Upgrader) Run() (err error) { // {{{
var version int
for dbName, dbase := range upgrader.databases {
@ -168,7 +185,7 @@ func (upgrader Upgrader) Run() (err error) {// {{{
}
upgrader.logCallback("exec", fmt.Sprintf("%s.%s: %d", dbName, upgrader.schema, version))
if _, err = dbase.db.Exec(string(sql)); err != nil {
if _, err = dbase.db.Exec(context.Background(), string(sql)); err != nil {
return
}
if err = dbase.appendSchemaVersion(version); err != nil {
@ -177,6 +194,6 @@ func (upgrader Upgrader) Run() (err error) {// {{{
}
}
return
}// }}}
} // }}}
// vim: foldmethod=marker