add PDO Sqlite driver WIP

docs/datetime.md

@@ -16,6 +16,7 @@ The following table presents a matrix of available DB date-time types:
 | MySQL       | `datetime`                               | `timestamp`                     | -                |
 | Postgres    | `timestamp`                              | `timestamptz`                   | -                |
 | SQL Server  | `datetime`, `datetime2`                  | -                               | `datetimeoffset` |
+| Sqlite      | -                                        | -                               | -
 
 - **no timezone handling**: database stores the time-stamp and does not do any modification to it; this is the easiest solution, but brings a disadvantage: database cannot exactly diff two time-stamps, i.e. it may produce wrong results because day-light saving shift is needed but db does not know which zone to use for the calculation;
 - **timezone conversion**: database stores the time-stamp unified in UTC and reads it in connection's timezone;
@@ -90,3 +91,25 @@ This will make Dbal fully functional, although some SQL queries and expressions
 |------|-------------|--------
 | local datetime     | `datetime`  | value is converted into application timezone
 | datetime           | `datetimeoffset` | value is read with timezone offset and no further modification is done - i.e. no application timezone conversion happens
+
+--------------------------
+
+### Sqlite
+
+Sqlite does not have a dedicated type for date time at all. However, Sqlite provides a function that helps to transform unix time to a local time zone.
+
+Use `datetime(your_column, 'unixepoch', 'localtime')` to convert stored timestamp to your local time-zone. Read more in the [official documentation](https://sqlite.org/lang_datefunc.html#modifiers).
+
+##### Writing
+
+| Type | Modifier | Comment
+|------|----------|--------
+| local datetime  | `%ldt`  | the timezone offset is removed and value is formatter as ISO string without the timezone offset
+| datetime        | `%dt`   | no timezone conversion is done and value is formatted as ISO string with timezone offset
+
+##### Reading
+
+| Type               | Column Type | Comment
+|--------------------|-------------|--------
+| local datetime     | ❌ | cannot be auto-detected
+| datetime           | ❌ | cannot be auto-detected

docs/default.md

@@ -6,15 +6,16 @@ Supported platforms:
 
 - **MySQL** via `mysqli` or `pdo_mysql` extension,
 - **Postgres** via `pgsql` or `pdo_pgsql` extension,
-- **MS SQL Server** via `sqlsrv` or `pdo_sqlsrv` extension.
+- **MS SQL Server** via `sqlsrv` or `pdo_sqlsrv` extension,
+- **Sqlite** via `pdo_sqlite` extension.
 
 ### Connection
 
 The Connection instance is the main access point to the database. Connection's constructor accepts a configuration array. The possible keys depend on the specific driver; some configuration keys are shared for all drivers. To actual list of supported keys are enumerated in PhpDoc comment in driver's source code.
 
-| Key                                   | Description
-| ---                                   | ---                |
-| `driver`                         | driver name, use `mysqli`, `pgsql`, `sqlsrv`, `pdo_mysql`, `pdo_pgsql`, `pdo_sqlsrv`
+| Key                                    | Description
+| ---                                    | ---                |
+| `driver`                               | driver name, use `mysqli`, `pgsql`, `sqlsrv`, `pdo_mysql`, `pdo_pgsql`, `pdo_sqlsrv`, `pdo_sqlite`
 | `host`                                 | database server name
 | `username`                             | username for authentication
 | `password`                             | password for authentication

readme.md

@@ -12,6 +12,7 @@ Supported platforms:
 - **MySQL** via `mysqli` or `pdo_mysql` extension,
 - **PostgreSQL** via `pgsql` or `pdo_pgsql` extension,
 - **MS SQL Server** via `sqlsrv` or `pdo_sqlsrv` extension.
+- **Sqlite** via `pdo_sqlite` extension.
 
 Integrations:
 - Symfony Bundle

src/Drivers/PdoSqlite/PdoSqliteDriver.php

@@ -0,0 +1,112 @@
+<?php declare(strict_types = 1);
+
+namespace Nextras\Dbal\Drivers\PdoSqlite;
+
+
+use DateTimeZone;
+use Exception;
+use Nextras\Dbal\Connection;
+use Nextras\Dbal\Drivers\Exception\ConnectionException;
+use Nextras\Dbal\Drivers\Exception\DriverException;
+use Nextras\Dbal\Drivers\Exception\ForeignKeyConstraintViolationException;
+use Nextras\Dbal\Drivers\Exception\NotNullConstraintViolationException;
+use Nextras\Dbal\Drivers\Exception\QueryException;
+use Nextras\Dbal\Drivers\Exception\UniqueConstraintViolationException;
+use Nextras\Dbal\Drivers\Pdo\PdoDriver;
+use Nextras\Dbal\Exception\NotSupportedException;
+use Nextras\Dbal\IConnection;
+use Nextras\Dbal\ILogger;
+use Nextras\Dbal\Platforms\IPlatform;
+use Nextras\Dbal\Platforms\SqlitePlatform;
+use Nextras\Dbal\Result\IResultAdapter;
+use PDOStatement;
+
+
+/**
+ * Driver for php_pdo_sqlite ext.
+ *
+ * Supported configuration options:
+ * - filename - file path to database or `:memory:`; defaults to :memory:
+ */
+class PdoSqliteDriver extends PdoDriver
+{
+	/** @var PdoSqliteResultNormalizerFactory */
+	private $resultNormalizerFactory;
+
+
+	public function connect(array $params, ILogger $logger): void
+	{
+		$file = $params['filename'] ?? ':memory:';
+		$dsn = "sqlite:$file";
+		$this->connectPdo($dsn, '', '', [], $logger);
+		$this->resultNormalizerFactory = new PdoSqliteResultNormalizerFactory();
+
+		$this->connectionTz = new DateTimeZone('UTC');
+		$this->loggedQuery('PRAGMA foreign_keys = 1');
+	}
+
+
+	public function createPlatform(IConnection $connection): IPlatform
+	{
+		return new SqlitePlatform($connection);
+	}
+
+
+	public function getLastInsertedId(?string $sequenceName = null)
+	{
+		return $this->query('SELECT last_insert_rowid()')->fetchField();
+	}
+
+
+	public function setTransactionIsolationLevel(int $level): void
+	{
+		static $levels = [
+			Connection::TRANSACTION_READ_UNCOMMITTED => 'READ UNCOMMITTED',
+			Connection::TRANSACTION_READ_COMMITTED => 'READ COMMITTED',
+			Connection::TRANSACTION_REPEATABLE_READ => 'REPEATABLE READ',
+			Connection::TRANSACTION_SERIALIZABLE => 'SERIALIZABLE',
+		];
+		if (!isset($levels[$level])) {
+			throw new NotSupportedException("Unsupported transaction level $level");
+		}
+		$this->loggedQuery("SET SESSION TRANSACTION ISOLATION LEVEL {$levels[$level]}");
+	}
+
+
+	protected function createResultAdapter(PDOStatement $statement): IResultAdapter
+	{
+		return (new PdoSqliteResultAdapter($statement, $this->resultNormalizerFactory))->toBuffered();
+	}
+
+
+	protected function convertIdentifierToSql(string $identifier): string
+	{
+		return '[' . strtr($identifier, '[]', '  ') . ']';
+	}
+
+
+	protected function createException(string $error, int $errorNo, string $sqlState, ?string $query = null): Exception
+	{
+		if (stripos($error, 'FOREIGN KEY constraint failed') !== false) {
+			return new ForeignKeyConstraintViolationException($error, $errorNo, '', null, $query);
+		} elseif (
+			strpos($error, 'must be unique') !== false
+			|| strpos($error, 'is not unique') !== false
+			|| strpos($error, 'are not unique') !== false
+			|| strpos($error, 'UNIQUE constraint failed') !== false
+		) {
+			return new UniqueConstraintViolationException($error, $errorNo, '', null, $query);
+		} elseif (
+			strpos($error, 'may not be NULL') !== false
+			|| strpos($error, 'NOT NULL constraint failed') !== false
+		) {
+			return new NotNullConstraintViolationException($error, $errorNo, '', null, $query);
+		} elseif (stripos($error, 'unable to open database') !== false) {
+			return new ConnectionException($error, $errorNo, '');
+		} elseif ($query !== null) {
+			return new QueryException($error, $errorNo, '', null, $query);
+		} else {
+			return new DriverException($error, $errorNo, '');
+		}
+	}
+}

src/Drivers/PdoSqlite/PdoSqliteResultAdapter.php

@@ -0,0 +1,100 @@
+<?php declare(strict_types = 1);
+
+namespace Nextras\Dbal\Drivers\PdoSqlite;
+
+
+use Nextras\Dbal\Exception\NotSupportedException;
+use Nextras\Dbal\Result\FullyBufferedResultAdapter;
+use Nextras\Dbal\Result\IResultAdapter;
+use Nextras\Dbal\Utils\StrictObjectTrait;
+use PDO;
+use PDOStatement;
+use function strtolower;
+
+
+class PdoSqliteResultAdapter implements IResultAdapter
+{
+	use StrictObjectTrait;
+
+
+	/** @var PDOStatement<mixed> */
+	private $statement;
+
+	/** @var bool */
+	private $beforeFirstFetch = true;
+
+	/** @var PdoSqliteResultNormalizerFactory */
+	private $normalizerFactory;
+
+
+	/**
+	 * @param PDOStatement<mixed> $statement
+	 */
+	public function __construct(PDOStatement $statement, PdoSqliteResultNormalizerFactory $normalizerFactory)
+	{
+		$this->statement = $statement;
+		$this->normalizerFactory = $normalizerFactory;
+	}
+
+
+	public function toBuffered(): IResultAdapter
+	{
+		return new FullyBufferedResultAdapter($this);
+	}
+
+
+	public function toUnbuffered(): IResultAdapter
+	{
+		return $this;
+	}
+
+
+	public function seek(int $index): void
+	{
+		if ($index === 0 && $this->beforeFirstFetch) {
+			return;
+		}
+
+		throw new NotSupportedException("PDO does not support rewinding or seeking. Use Result::buffered() before first consume of the result.");
+	}
+
+
+	public function fetch(): ?array
+	{
+		$this->beforeFirstFetch = false;
+		$fetched = $this->statement->fetch(PDO::FETCH_ASSOC);
+		return $fetched !== false ? $fetched : null;
+	}
+
+
+	public function getRowsCount(): int
+	{
+		return $this->statement->rowCount();
+	}
+
+
+	public function getTypes(): array
+	{
+		$types = [];
+		$count = $this->statement->columnCount();
+
+		for ($i = 0; $i < $count; $i++) {
+			$field = $this->statement->getColumnMeta($i);
+			if ($field === false) { // @phpstan-ignore-line
+				// Sqlite does not return meta for special queries (PRAGMA, etc.)
+				continue;
+			}
+
+			$type = strtolower($field['sqlite:decl_type'] ?? $field['native_type'] ?? '');
+			$types[(string) $field['name']] = $type;
+		}
+
+		return $types;
+	}
+
+
+	public function getNormalizers(): array
+	{
+		return $this->normalizerFactory->resolve($this->getTypes());
+	}
+}

src/Drivers/PdoSqlite/PdoSqliteResultNormalizerFactory.php

@@ -0,0 +1,78 @@
+<?php declare(strict_types = 1);
+
+namespace Nextras\Dbal\Drivers\PdoSqlite;
+
+
+use Closure;
+use Nextras\Dbal\Utils\StrictObjectTrait;
+
+
+/**
+ * @internal
+ */
+class PdoSqliteResultNormalizerFactory
+{
+	use StrictObjectTrait;
+
+
+	/** @var Closure(mixed): mixed */
+	private $intNormalizer;
+
+	/** @var Closure(mixed): mixed */
+	private $floatNormalizer;
+
+
+	public function __construct()
+	{
+		$this->intNormalizer = static function ($value): ?int {
+			if ($value === null) return null;
+			return (int) $value;
+		};
+
+		$this->floatNormalizer = static function ($value): ?float {
+			if ($value === null) return null;
+			return (float) $value;
+		};
+	}
+
+
+	/**
+	 * @param array<string, mixed> $types
+	 * @return array<string, callable (mixed): mixed>
+	 */
+	public function resolve(array $types): array
+	{
+		static $ints = [
+			'int' => true,
+			'integer' => true,
+			'tinyint' => true,
+			'smallint' => true,
+			'mediumint' => true,
+			'bigint' => true,
+			'unsigned big int' => true,
+			'int2' => true,
+			'int8' => true,
+		];
+
+		static $floats = [
+			'real' => self::TYPE_FLOAT,
+					'double' => self::TYPE_FLOAT,
+					'double precision' => self::TYPE_FLOAT,
+					'float' => self::TYPE_FLOAT,
+					'numeric' => self::TYPE_FLOAT,
+					'decimal' => self::TYPE_FLOAT,
+		];
+
+		$normalizers = [];
+		foreach ($types as $column => $type) {
+			if ($type === 'text' || $type === 'varchar') {
+				continue; // optimization
+			} elseif ($type === 'integer') {
+				$normalizers[$column] = $this->intNormalizer;
+			} elseif ($type === 'real') {
+				$normalizers[$column] = $this->floatNormalizer;
+			}
+		}
+		return $normalizers;
+	}
+}

src/Platforms/IPlatform.php

@@ -15,6 +15,7 @@ interface IPlatform
 	public const SUPPORT_MULTI_COLUMN_IN = 1;
 	public const SUPPORT_QUERY_EXPLAIN = 2;
 	public const SUPPORT_WHITESPACE_EXPLAIN = 3;
+	public const SUPPORT_INSERT_DEFAULT_KEYWORD = 4;
 
 
 	/**