Module SQLite

SQLite interface to be used with Python projects. Can be installed by pip install macwinnie_sqlite3

Classes

class database (dbPath, migrationsPath=None)

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class database:

    def __init__(self, dbPath, migrationsPath=None):
        self.connection = None
        self.result = None
        self.dbPath = dbPath
        if migrationsPath != None:
            self.migrate(migrationsPath)

    def __getattr__(self, name):
        """magic method to use given methods of database response objects like `fetchall` or `fetchone`."""

        # args:   positional arguments
        # kwargs: keyword arguments
        def method(*args, **kwargs):
            cllbl = getattr(self.result, name)
            if callable(cllbl):
                return cllbl(*args, **kwargs)
            else:
                return cllbl

        return method

    def migrate(self, migrationsPath):
        """Method to apply yoyo-migrations to database"""
        backendS = "sqlite:///{}".format(self.dbPath)
        # ensure DB file exists
        if not os.path.isfile(self.dbPath):
            open(self.dbPath, "w").close()
        # ensure all DB migrations are applied
        backend = yoyo.get_backend(backendS)
        migrations = yoyo.read_migrations(migrationsPath)
        with backend.lock():
            backend.apply_migrations(backend.to_apply(migrations))

    def startAction(self):
        """Connect to database and so start an action"""
        if self.connection != None:
            raise Exception("DB already connected!")
        self.connection = sqlite3.connect(self.dbPath)

    def execute(self, query, params=None):
        """execute SQL statement on database"""
        if params is None:
            params = []
        self.result = self.connection.cursor()
        self.result.execute(query, params)

    def commitAction(self):
        """commit your actions done through the execute statements between `startAction` and `commitAction` – so finish the transaction."""
        self.connection.commit()
        self.close()

    def fullExecute(self, query, params=None):
        """combination method for a full transaction"""
        if params is None:
            params = []
        self.startAction()
        self.execute(query, params)
        self.commitAction()

    def rollbackAction(self):
        """method to roll back executed statements from `startAction` until `rollbackAction` without `commitAction` has been invoked."""
        self.connection.rollback()
        self.close()

    def close(self):
        """clean close of the database connection"""
        self.connection.close()
        self.connection = None

    def fetchallNamed(self):
        """regular `fetchall` for the results of `SELECT` statements executed return lists of lists of values. This method migrates those inner lists to key-value dicts."""
        rowKeys = [i[0] for i in self.description()]
        allResults = self.fetchall()
        allReturn = []
        for ar in allResults:
            allReturn.append(dict(zip(rowKeys, ar)))
        return allReturn

    def fetchoneNamed(self):
        """regular `fetchone` for results of `SELECT` statements executed return a list of values. This method migrates those lists to key-value dicts."""
        rowKeys = [i[0] for i in self.description()]
        results = self.fetchone()
        toReturn = dict(zip(rowKeys, results))
        return toReturn

Methods

def close(self)

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def close(self):
    """clean close of the database connection"""
    self.connection.close()
    self.connection = None

clean close of the database connection

def commitAction(self)

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def commitAction(self):
    """commit your actions done through the execute statements between `startAction` and `commitAction` – so finish the transaction."""
    self.connection.commit()
    self.close()

commit your actions done through the execute statements between startAction and commitAction – so finish the transaction.

def execute(self, query, params=None)

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def execute(self, query, params=None):
    """execute SQL statement on database"""
    if params is None:
        params = []
    self.result = self.connection.cursor()
    self.result.execute(query, params)

execute SQL statement on database

def fetchallNamed(self)

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def fetchallNamed(self):
    """regular `fetchall` for the results of `SELECT` statements executed return lists of lists of values. This method migrates those inner lists to key-value dicts."""
    rowKeys = [i[0] for i in self.description()]
    allResults = self.fetchall()
    allReturn = []
    for ar in allResults:
        allReturn.append(dict(zip(rowKeys, ar)))
    return allReturn

regular fetchall for the results of SELECT statements executed return lists of lists of values. This method migrates those inner lists to key-value dicts.

def fetchoneNamed(self)

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def fetchoneNamed(self):
    """regular `fetchone` for results of `SELECT` statements executed return a list of values. This method migrates those lists to key-value dicts."""
    rowKeys = [i[0] for i in self.description()]
    results = self.fetchone()
    toReturn = dict(zip(rowKeys, results))
    return toReturn

regular fetchone for results of SELECT statements executed return a list of values. This method migrates those lists to key-value dicts.

def fullExecute(self, query, params=None)

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def fullExecute(self, query, params=None):
    """combination method for a full transaction"""
    if params is None:
        params = []
    self.startAction()
    self.execute(query, params)
    self.commitAction()

combination method for a full transaction

def migrate(self, migrationsPath)

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def migrate(self, migrationsPath):
    """Method to apply yoyo-migrations to database"""
    backendS = "sqlite:///{}".format(self.dbPath)
    # ensure DB file exists
    if not os.path.isfile(self.dbPath):
        open(self.dbPath, "w").close()
    # ensure all DB migrations are applied
    backend = yoyo.get_backend(backendS)
    migrations = yoyo.read_migrations(migrationsPath)
    with backend.lock():
        backend.apply_migrations(backend.to_apply(migrations))

Method to apply yoyo-migrations to database

def rollbackAction(self)

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def rollbackAction(self):
    """method to roll back executed statements from `startAction` until `rollbackAction` without `commitAction` has been invoked."""
    self.connection.rollback()
    self.close()

method to roll back executed statements from startAction until rollbackAction without commitAction has been invoked.

def startAction(self)

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def startAction(self):
    """Connect to database and so start an action"""
    if self.connection != None:
        raise Exception("DB already connected!")
    self.connection = sqlite3.connect(self.dbPath)

Connect to database and so start an action