ecn-robots: reimplemented PostgreSQL robot using psycopg2

pgdb.py

@@ -1,12 +1,17 @@
-'Python interface to PostgreSQL for managing database nodes.'
+r'''Python interface to PostgreSQL for managing database nodes.
+'''
 
 from subprocess import Popen, PIPE
+import psycopg2 
+import psycopg2.extensions
 
 class Db(object):
     
     def __init__(self,name):
         self._name = name
-        self._p = Popen('/usr/bin/psql -Aqt -U postgres', stdin=PIPE, stdout=PIPE, stderr=PIPE, shell=True)
+        self.conn = psycopg2.connect("dbname='postgres' user='postgres' host='localhost' password=''");
+	self.conn.set_isolation_level(psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT)
+	self.cursor = self.conn.cursor()
 
     def _run(self, command,args=[]):
         execfn = [command] + list(args)
@@ -19,77 +24,77 @@ class Db(object):
 
     def _runsql(self, sql, db='postgres'):
 	given_sql = sql
-        sql = sql +'\echo this is the end' +'\n'
-        self._p.stdout.flush()
-        self._p.stdin.write(str(sql))
-	out = ""
-	out  = self._p.stdout.readline()
-	while out.find("this is the end") == -1:
-	    out = out +self._p.stdout.readline()
-        lout = out.replace('this is the end','')
-	return lout.strip()
+        self.cursor.execute(given_sql)
+	try:
+	    out = self.cursor.fetchall()
+	except Exception,e: 
+	    out = "Executed with exception "
+        return out
     
     def _get_owner(self):
-        sql = "SELECT pg_get_userbyid(datdba) FROM pg_database WHERE datname ='"+self.sanitize(self._name)+"';"
+        sql = "SELECT pg_get_userbyid(datdba) FROM pg_database WHERE datname ='"+self._name+"';"
 	own = self._runsql(sql)
         return own
 
     def _set_owner(self, owner):
-        sql = "ALTER DATABASE "+self._name+" OWNER TO "+self.sanitize(owner)+";"
+        sql = "ALTER DATABASE "+self._name+" OWNER TO "+owner+";"
         own = self._runsql(sql)
 	return own
     
-    db_owner = property(_get_owner, _set_owner)
+    owner = property(_get_owner, _set_owner)
 
     @property
-    def db_OID(self):
-        sql = "SELECT oid FROM pg_database WHERE datname = '"+self.sanitize(self._name)+"';"
+    def OID(self):
+        sql = "SELECT oid FROM pg_database WHERE datname = '"+self._name+"';"
 	oid = self._runsql(sql)
 	return oid
 
     @property
-    def db_info(self):
+    def info(self):
         information = {'size':'', 'encoding':'', 'collation':'','ctype':''}
-        information['size'] = self._runsql("SELECT pg_size_pretty(pg_database_size('"+self.sanitize(self._name)+"'));")
-        information['encoding'], information['collation'], \
-	    information['ctype'] = self._runsql("SELECT pg_encoding_to_char(encoding), datcollate, datctype FROM pg_database WHERE datname='"+self.sanitize(self._name)+"';").split('|')
+        information['size'] = self._runsql("SELECT pg_size_pretty(pg_database_size('"+self._name+"'));")
+        inf = self._runsql("""SELECT pg_encoding_to_char(encoding), 
+	                datcollate, datctype FROM pg_database WHERE datname='"""+self._name+"';")
+        information['encoding'] = inf[0][0]
+	information['collation'] = inf[0][1]
+        information['ctype'] = inf[0][2]
         return information
 
     @property
-    def db_connections(self):
-        sql = "SELECT numbackends from pg_stat_database WHERE datname = '"+self.sanitize(self._name)+"';"
+    def connections(self):
+        sql = "SELECT numbackends from pg_stat_database WHERE datname = '"+self._name+"';"
 	cncs = self._runsql(sql)
 	return cncs
     
     def user_exists(self, user):
-        sql = "SELECT rolname FROM pg_authid WHERE rolname = '"+self.sanitize(user)+"';"
+        sql = "SELECT rolname FROM pg_authid WHERE rolname = '"+user+"';"
 	u = self._runsql(sql)
-	if (u == ""):
+	if (len(u) == 0):
 	    return False
 	return True
 
     def db_exists(self, xdb):
-        sql = "SELECT datname FROM pg_database WHERE datname = '"+self.sanitize(xdb)+"';"
+        sql = "SELECT datname FROM pg_database WHERE datname = '"+xdb+"';"
 	d = self._runsql(sql)
-        if (d == ""):
+        if (len(d) == 0):
 	    return False
 	return True
 
-    def db_delete(self):
+    def delete(self):
         if self.db_exists(self._name) == True:
-            sql = "DROP DATABASE "+self.sanitize(self._name)+";"
+            sql = "DROP DATABASE "+self._name+";"
 	    drop = self._runsql(sql)
 	    return drop
         return "Failed"
 
-    def db_create(self, own, coll, ctyp, enc=u'UTF8'):
+    def create(self, own, coll, ctyp, enc=u'UTF8'):
         if self.db_exists(self._name) == False:
-	    sql = "CREATE DATABASE "+self.sanitize(self._name)+" WITH OWNER = "+self.sanitize(own)+" ENCODING = '"+self.sanitize(enc)+"' LC_COLLATE = '"+self.sanitize(coll)+"' LC_CTYPE = '"+self.sanitize(ctyp)+"';"
+	    sql = "CREATE DATABASE "+self._name+" WITH OWNER = "+own+" ENCODING = '"+enc+"' LC_COLLATE = '"+coll+"' LC_CTYPE = '"+ctyp+"';"
 	    create = self._runsql(sql)
 	    return create
         return "Failed"
 
-    def db_dump(self, path, method):
+    def dump(self, path, method):
         dump = Popen(['/usr/bin/pg_dump', '-U','postgres','-F'+ method, self._name], stdout=PIPE)
 	fl = open(path,"wb")
 	gz = Popen(['gzip'], stdin = dump.stdout, stdout = fl)
@@ -97,46 +102,50 @@ class Db(object):
 	return "Finished dumping "+self._name
 
 
-    def db_rename(self,old, new):
+    def rename(self,old, new):
         if self.db_exists(new) == True or self.db_exists(old) == False:
 	    return "Cannot"
-	sql = "ALTER DATABASE "+self.sanitize(old)+" RENAME TO "+self.sanitize(new)+";"
+	sql = "ALTER DATABASE "+old+" RENAME TO "+new+";"
 	rename = self._runsql(sql)
 	return rename
 
     def copy():
         pass
 
-    def db_list(self):
+    def dblist(self):
         sql = "SELECT datname FROM pg_database WHERE datname NOT IN ('template0', 'template1', 'postgres');"
-	dbl = self._runsql(sql)
-	return dbl
+	dblist = self._runsql(sql)
+	return dblist
 
-    def usr_list(self):
+    def usrlist(self):
         sql = "SELECT rolname FROM pg_authid WHERE rolcanlogin=true;"
-	usrl = self._runsql(sql)
-	return usrl
-
-    def usr_add(self, us, passw):
-        sql = "CREATE ROLE "+self.sanitize(us)+" WITH NOSUPERUSER NOCREATEDB NOCREATEROLE NOCREATEUSER LOGIN PASSWORD '"+self.sanitize(passw)+"';"
-        usra = self._runsql(sql)
-        return usra
-
-    def usr_delete(self, us):
-        sql = "DROP ROLE IF EXISTS "+self.sanitize(us)+";"
-        usrd = self._runsql(sql)
-        return usrd
-    
-    def sanitize(self,s):
-        mset = '0123456789ABCDEFGHIJKLMNOPRSTUVXYZabcdefghijklmnoprstuvxyz-_.'
-        return ''.join([c for c in s if c in mset])
+	usrlist = self._runsql(sql)
+	return usrlist
 
 def _test():
     test = Db(u'postgres')
-    print    test.db_list()
-    print    test.usr_list()
-    print test.db_info['encoding'], test.info['collation'], test.info['ctype']
-    print test.sanitize("aaaa-fgdg?sd/!_fb*gs'h;s'hdghj.dn ")
+    print "                             "
+    print 'Encoding is ',test.info['encoding'], 'Collation is ',test.info['collation'], 'CType is ',test.info['ctype']
+#    print test.owner
+#    print test.connections
+    print "User aaa is ",test.user_exists("aaa")
+    print "User postgres is ",test.user_exists("postgres")
+    print "database xxxaaa is ", test.db_exists("xxxaaa")
+    print "database postgres is ", test.db_exists("postgres")
+    print test.dblist()
+    test2 = Db(u'test')
+#    print test2.create(u'postgres', u'en_US.UTF-8', u'en_US.UTF-8')
+    print test2.dblist()
+    test2.rename(u'test',u'bbb')
+    print test2.dblist()
+    #print test2.usrlist()
+    #print test2.owner
+    #test2.owner = u'karasz'
+    #print test2.owner
+    #test = Db(u'aaa')
+    #test.create(u'postgres', u'en_US.UTF-8', u'en_US.UTF-8')
+ #   print test.dump('/tmp/aaa.gz',u'p')
+    #test.delete()
 if __name__ == '__main__':
     _test()