Teil17 Datenbanken

db/testdb.py

@@ -1,65 +0,0 @@
-import unittest
-from  DBConnection import DBConnection
-import logging
-
-logging.basicConfig( format='%(asctime)-15s [%(levelname)s] %(funcName)s: %(message)s', level=logging.DEBUG)
-
-class TestDBConnection(unittest.TestCase):
-
-  @classmethod
-  def setUpClass(cls):
-    logging.debug(f'setUpClass() {cls}')
-
-    cls.db_connection = DBConnection()
-    cls.db_connection.connect('database','piuser','SW_Ep.6:ROTJ','pidb')
-    logging.debug('erzeuge Table fib...')
-    cls.db_connection.execute_query('create table if not exists fib (id int auto_increment primary key, wert int)')
-    cls.db_connection.execute_query('create table if not exists schueler (id int auto_increment primary key, vorname varchar(20),name varchar(20))')
-    logging.debug('setup() fertig')
-
-  @classmethod
-  def tearDownClass(cls):
-    logging.debug(f'tearDownClass() {cls}')
-
-    logging.debug('Räume Tables auf')
-    cls.db_connection.execute_query('drop table if exists fib')
-    cls.db_connection.execute_query('drop table if exists schueler')
-    logging.debug('schliesse Datenbankverbindung.')
-    cls.db_connection.disconnect()
-    cls.db_connection = None
-
-
-  def test_insert(self):
-    logging.debug(f'connected= {self.db_connection.isConnected()}')
-    self.assertTrue(self.db_connection.isConnected())
-    self.db_connection.execute_query("insert into schueler (name,vorname) values('Simpson','Bart')")
-    self.db_connection.execute_query("insert into schueler (name,vorname) values('Simpson','Lisa')")
-    self.db_connection.execute_query("insert into schueler (name,vorname) values('van Houten','Milhouse')")
-    self.db_connection.execute_query("insert into schueler (name,vorname) values('Wiggum','Ralph')")
-#    input('Press Any Key')
-
-  def test_select(self):
-#    self.test_insert()
-    self.assertTrue(self.db_connection.isConnected())
-    result = self.db_connection.execute_query("select * from  schueler where name='Simpson'")
-    self.assertEqual(2,len(result))
-    result = self.db_connection.execute_query("select * from  schueler")
-    self.assertEqual(4,len(result))
-
-  def test_connected(self):
-    self.assertTrue(self.db_connection.isConnected())
-
-  def test_disconnect(self):
-    self.db_connection.disconnect()
-    self.assertFalse(self.db_connection.isConnected())
-
-  def test_create_table(self):
-    self.assertTrue(self.db_connection.isConnected())
-
-      
-    
-
-
-if __name__ =='__main__':
-  unittest.main()
-

db/.gitignore → teil17/.gitignore

@@ -1,2 +1,3 @@
 ./__pycache__
+./db.ini
 ./network/__pycache__/*

db/DBConnection.py → teil17/DBConnection.py

@@ -1,3 +1,4 @@
+#encoding: utf-8
 import mysql.connector
 import logging
 
@@ -7,47 +8,38 @@ class DBConnection():
   def __init__(self):
     self.dbconnection = None
 
+  #Verbindung zur Datenbank mit den übergebenen Wreten herstellen.
   def connect(self, host, user, password, database):
 
     self.connection= mysql.connector.connect(host=host, user=user,password=password,database=database)
-    logging.debug(f'Datenbankverbindung aufgebaut ${self.connection}')
-    logging.debug(f'Cursor gesetzt ${self.cursor}')
 
+ # Verbindung trennen
   def disconnect(self):
     if self.connection is not None:
       self.connection.close()
+      self.connection = None
 
+  # Schüler-Record in  die Tabelle einfügen.
+  def insertSchueler(self,schueler):
+    self.execute_query('insert into schueler (name,vorname) values(%s,%s)', (schueler['name'],schueler['vorname']))
 
+  # Liefert True, wenn die Verbindung zur DB besteht, sonst False    
   def isConnected(self):
-#    logging.debug(f'connection={self.connection}')
-#    logging.debug(f'connected= {self.connection.is_connected()}')
     if self.connection is not None:
       return self.connection.is_connected()
     return False
 
+  # Wenn DB-Verbindung besteht, wird der Cursor geliefert, sonst None
   def cursor(self):
      if self.isConnected():
        return self.connection.cursor()
      return None
 
-  def insert(self,cmd):
-    pass
-
-  def fetch(self):
-    pass  
-
-  def create_table(self):
-    pass
-
+  # Datenbank Kommando ausführen. Das params-Tupel wird in die Query eingesetzt.
+  # Liefert ein Resultset zurück.
   def execute_query(self, query, params = None):
     if self.isConnected():
       cursor = self.cursor()
       if cursor is not None:
-        cursor.execute(query,params)
-        return cursor.fetchall()
-
-
-
-  
-
-
+        cursor.execute(query,params) #Kommdo ausführen
+        return cursor.fetchall() # Ergebnis zurückliefern.

teil17/db.ini.sample

@@ -0,0 +1,8 @@
+[pidb]
+host=database
+user=piuser
+password=<passwort>
+database=pidb
+
+
+

teil17/testdb.py

@@ -0,0 +1,88 @@
+#!/usr/bin/python3
+# encoding:utf-8
+
+import unittest
+from  DBConnection import DBConnection
+import logging
+import configparser
+
+logging.basicConfig( format='%(asctime)-15s [%(levelname)s] %(funcName)s: %(message)s', level=logging.DEBUG)
+
+schueler = [
+    {'name':'Simpson','vorname': 'Bart'},
+    {'name':'Simpson','vorname':'Lisa'},
+    {'name':'van Houten','vorname':'Milhouse'},
+    {'name':'Wiggum','vorname':'Ralph'},
+    {'name':'Jones','vorname':'Jimbo'}
+]
+
+class TestDBConnection(unittest.TestCase):
+
+  @classmethod
+  def setUpClass(cls):
+    logging.debug(f'setUpClass() {cls}')
+
+    config = configparser.ConfigParser()
+    config.read('db.ini')
+    logging.debug(f"host={config['pidb']['host']}")
+
+    cls.db_connection = DBConnection()
+    cls.db_connection.connect(config['pidb']['host'],config['pidb']['user'],config['pidb']['password'],config['pidb']['database'])
+    if cls.db_connection.isConnected():
+      logging.debug('erzeuge Table schueler...')
+      cls.db_connection.execute_query('create table if not exists schueler (id int auto_increment primary key, vorname varchar(20),name varchar(20))')
+
+    # Testdaten aufbauen.
+    cls.fill_table()
+    logging.debug('setup() fertig')
+
+  @classmethod
+  def tearDownClass(cls):
+    logging.debug(f'tearDownClass() {cls}')
+
+    logging.debug('Räume Tables auf')
+    cls.db_connection.execute_query('drop table if exists schueler')
+    logging.debug('schliesse Datenbankverbindung.')
+    cls.db_connection.disconnect()
+    cls.db_connection = None
+
+
+#    input('Press Any Key')
+
+  #Testdaten in die Datenbank übertragen
+  @classmethod
+  def fill_table(cls):
+    for s in range(0,len(schueler)):
+      student = schueler[s]
+      cls.db_connection.insertSchueler(student)
+
+# Nur die Records mit Nachname ='Simpson' lesen
+  def test_select_name(self):
+    self.assertTrue(self.db_connection.isConnected())
+    
+    result = self.db_connection.execute_query("select * from  schueler where name='Simpson'")
+    self.assertEqual(2,len(result))
+
+  def test_select_all(self):
+#    self.test_insert()
+    result = self.db_connection.execute_query("select * from  schueler")
+    logging.debug(f'result={result}')
+    self.assertEqual(len(schueler),len(result))
+    
+    for i in range(len(result)):
+      self.assertEqual(schueler[i]['vorname'], result[i][1])
+
+  def test_connected(self):
+    self.assertTrue(self.db_connection.isConnected())
+
+
+  def test_create_table(self):
+    self.assertTrue(self.db_connection.isConnected())
+
+      
+    
+
+
+if __name__ =='__main__':
+  unittest.main()
+