Source Code for Module turbogears.command.sacommand

  1  from peak.rules import abstract, when, around 
  2  from turbogears import config 
  3  from turbogears.util import get_model 
  4  from turbogears.decorator import simple_decorator 
  5  try: 
  6      from sqlalchemy import MetaData, exceptions, Table, String, Unicode 
  7      from turbogears.database import bind_metadata, metadata, get_engine 
  8  except ImportError: # if not available, complain only at run-time 
  9      from turbogears.util import missing_dependency_error 
 10      no_sqlalchemy = missing_dependency_error('SQLAlchemy') 
 11  else: 
 12      from sqlalchemy import Text, UnicodeText 
 13      no_sqlalchemy = False 
 14   
 15   
 16  @abstract() 
 17 -def sacommand(command, args): 
 18      pass 
 19   
 20  @around(sacommand, "command and command != 'help' and no_sqlalchemy") 
 21 -def no_engine(command, args): 
 22      print no_sqlalchemy 
 23   
 24  @when(sacommand, "command == 'help'") 
 25 -def help(command, args): 
 26      print """TurboGears SQLAlchemy Helper 
 27   
 28  tg-admin sql command [options] 
 29   
 30  Available commands: 
 31      create  Create tables 
 32      execute Execute SQL statements 
 33      help    Show help 
 34      list    List tables that appear in the model 
 35      status  Show differences between model and database 
 36  """ 
 37   
 38  @when(sacommand, "command == 'create'") 
 39 -def create(command, args): 
 40      print "Creating tables at %s" % (config.get("sqlalchemy.dburi")) 
 41      bind_metadata() 
 42      get_model() 
 43      metadata.create_all() 
 44   
 45  @when(sacommand, "command == 'list'") 
 46 -def list_(command, args): 
 47      get_model() 
 48      for tbl in metadata.tables.values(): 
 49          print tbl.fullname 
 50   
 51  @when(sacommand, "command == 'execute'") 
 52 -def execute(command, args): 
 53      eng = get_engine() 
 54      for cmd in args[2:]: 
 55          ret = eng.execute(cmd) 
 56          try: 
 57              print list(ret) 
 58          except: 
 59              # Proceed silently if the command produced no results 
 60              pass 
 61   
 62  @when(sacommand, "command == 'status'") 
 63 -def status(command, args): 
 64      bind_metadata() 
 65      get_model() 
 66      ret = compare_metadata(metadata, MetaData(metadata.bind)) 
 67      for l in ret: 
 68          print l 
 69      if not ret: 
 70          print "Database matches model" 
 71   
 72 -def indent(ls): 
 73      return ['    ' + l for l in ls] 
 74   
 75 -def compare_metadata(pym, dbm): 
 76      rc = [] 
 77      for pyt in pym.tables.values(): 
 78          try: 
 79              dbt = Table(pyt.name, dbm, autoload=True, schema=pyt.schema) 
 80          except exceptions.NoSuchTableError: 
 81              rc.extend(("Create table " + pyt.fullname, '')) 
 82          else: 
 83              ret = compare_table(pyt, dbt) 
 84              if ret: 
 85                  rc.append("Change table " + pyt.fullname) 
 86                  rc.extend(indent(ret) + ['']) 
 87      return rc 
 88   
 89 -def compare_table(pyt, dbt): 
 90      rc = [] 
 91      dbcols = dict([(s.lower(), s) for s in dbt.columns.keys()]) 
 92      for pyc in pyt.columns: 
 93          name = pyc.name.lower() 
 94          if dbcols.has_key(name): 
 95              ret = compare_column(pyc, dbt.columns[dbcols[name]]) 
 96              if ret: 
 97                  rc.append("Change column " + pyc.name) 
 98                  rc.extend(indent(ret)) 
 99              dbcols.pop(name) 
100          else: 
101              rc.append("Add column " + pyc.name) 
102      for dbcol in dbcols: 
103          rc.append("Remove column " + dbcol) 
104      return rc 
105   
106 -def compare_column(pyc, dbc): 
107      rc = [] 
108      pyt, dbt = pyc.type, dbc.type 
109   
110      # Table reflection cannot recognize Unicode, so check only for String 
111      if isinstance(pyt, Unicode): 
112          pyt = String(pyt.length) 
113      elif isinstance(pyt, UnicodeText): 
114          pyt = Text(pyt.length) 
115   
116      # Check type 
117      if not isinstance(dbt, pyt.__class__): 
118          rc.append('Change type to ' + pyt.__class__.__name__) 
119   
120      # Check length (for strings) 
121      else: 
122          if isinstance(pyt, String): 
123              if pyt.length != dbt.length: 
124                  rc.append('Change length to ' + str(pyt.length)) 
125   
126      # Check primary key 
127      if dbc.primary_key != pyc.primary_key: 
128          rc.append(pyc.primary_key and 'Make primary key' or 'Remove primary key') 
129   
130      # TODO: Check foreign keys 
131   
132      # Check default 
133      if (dbc.default is not None and pyc.default is not None 
134              and dbc.default != pyc.default): 
135          rc.append('Change default to ' + str(pyc.default.arg)) 
136   
137      # Check index 
138      if dbc.index is not None and dbc.index != pyc.index: 
139          rc.append(pyc.index and 'Add index' or 'Remove index') 
140   
141      return rc 
142