pooling 0.1.12
pooling anything.
License: MIT
Keywords: pooling

# pooling

pooling anything.

## Install

```
pip install pooling
```

## Usage Example 1


```
import MySQLdb
from MySQLdb.cursors import DictCursor

from pooling import PoolBase

class MysqlConnectionPool(PoolBase):
    
    def do_session_create(self, *create_args, **create_kwargs):
        create_kwargs.setdefault("cursorclass", DictCursor)
        create_kwargs.setdefault("autocommit", True)
        create_kwargs.setdefault("charset", "utf8mb4")
        return MySQLdb.connect(*create_args, **create_kwargs)

    def do_session_destory(self, real_session):
        real_session.close()

if __name__ == "__main__":
    conn_info = {
        "host": "127.0.0.1",
        "port": 3306,
        "user": "test",
        "password": "test",
        "db": "test",
    }
    pool = MysqlConnectionPool(pool_size=10, kwargs=conn_info)
    connection = pool.get_session()
    cursor = connection.cursor()
    count = cursor.execute("show databases")
    data = cursor.fetchall()
    print("rows count=", count)
    print("data=", data)
    assert count == len(data)

```

## Usage Example 2

```
import MySQLdb
from MySQLdb.cursors import DictCursor

from pooling import Pool

def mysql_conn_create():
    conn_info = {
        "host": "127.0.0.1",
        "port": 3306,
        "user": "test",
        "password": "test",
        "db": "test",
    }
    conn = MySQLdb.connect(cursorclass=DictCursor, autocommit=True, **conn_info)
    return conn

def mysql_conn_close(session):
    session.close()

if __name__ == "__main__":
    pool = Pool(pool_size=10, create_factory=mysql_conn_create, destory_factory=mysql_conn_close)
    connection = pool.get_session()
    cursor = connection.cursor()
    count = cursor.execute("show databases")
    data = cursor.fetchall()
    print("rows count=", count)
    print("data=", data)
    assert count == len(data)
```

## Usage Example 3

```
conn_info = {
    "host": "127.0.0.1",
    "port": 3306,
    "user": "test",
    "password": "test",
    "db": "test",
}

from pooling.mysql import MysqlConnectionPool

pool = MysqlConnectionPool(10, kwargs=conn_info)
connection = pool.get_session()
cursor = connection.cursor()
count = cursor.execute("show databases")
data = cursor.fetchall()
print("rows count=", count)
print("data=", data)
assert count == len(data)
```

## Usage Example 4

```
conn_info = {
    "host": "127.0.0.1",
    "port": 3306,
    "user": "test",
    "password": "test",
    "db": "test",
}

from pooling.mysql import MysqlConnectionPool

pool = MysqlConnectionPool(10, kwargs=conn_info)
data = pool.query("select * from table1")
for row in data:
    print(row)

```

## Note

* Call pool.get_session() returns a proxied connection instance.
* The returned proxied connection instance is a proxy instance of the real connection.
* When the returned proxied connection is being deleted, the real connection will be returned to the pool so that the real connection can be used again.
* A simple mysql connection pool can be imported by doing `from pooling.mysql import MysqlConnectionPool`. Compare with the `MysqlConnectionPool` implemented in `Usage Example 1`, it add ping() test and errors handler in get_session() method.
* The `pooling.mysql` module depends on `mysqlclient`, but `pooling` is NOT, so that `mysqlclient` is not auto installed after `pooling` installed. You should do `pip install mysqlclient` by yourself if you want to use `MysqlConnectionPool`.
* If you want to use `MysqlConnectorPool`, you need to install package `mysql-connector-python` by yourself.
* If you want to use `PyMySQLConnectionPool`, you need to install package `PyMySQL` by yourself.

## Releases

### v0.1.0

- First release.

### v0.1.1

- `MysqlConnectionPool.get_session()` do `connection.ping()` to make sure the connection is avaiable.
- `Pool.counter` and `Pool.version` use thread safe counter.

### v0.1.2

- Fix problem in using `get_session` with `with` statement. `with pool.get_session() as session: pass` got the real session instread of our wrapped Session.

### v0.1.5

- Fix problem in handling a proxied real-session instance.
- Fix un-sleep-problem while connecting to mysql server failed.
- Add python2.7 support.

### v0.1.6

- Use zenutils.importutils.
- Fix get_session timeout calc problem.

### v0.1.7

- Unit test passed.

### v0.1.8

- Add _pooling_is_connection_closed test.

### v0.1.9

- Fix doing useless time.sleep problem in pooling.mysql.MysqlConnectionPoolBase.get_session.
- Add pooling.mysql.PyMySQLConnectionPool.

### v0.1.10

- Fix PoolBase.return_session double called in `with pool.get_session() as session: pass`.
- PoolBase add ping_test support.

### v0.1.11

- Doc update.

### v0.1.12

- Doc update.