Source Code for Module park.core.user

 1  # This program is public domain 
 2  """ 
 3  Resource management. 
 4   
 5  Handles authentication, privilege, resource accounting and notification 
 6  for individual users on the server. 
 7   
 8  Maps to a backend user database and resource database. 
 9  """ 
10   
11 -class Usage(object): 
12      """ 
13      Resource management. 
14   
15      Resource management is based on domains.  All jobs in the particular 
16      domain have the same privileges.  Note that domain is explicitly 
17      separate from any concept of user so that we can separate privilege 
18      from identity.  In systems with full user accounting, each user id 
19      may be a separate domain.  In looser systems where users are not 
20      explicitly identified, the domain may be something like the IP 
21      address of the client. 
22   
23      By default all jobs compete for resources at an equal level with 
24      no limits on the number of jobs that can be requested. 
25      """ 
26      id = "" 
27      """Unique id for the resource domain""" 
28      priority = 0 
29      """Priority for jobs in this domain""" 
30      credit = -1 
31      """Amount of credit remaining in this domain, or -1 if unlimited""" 
32      cpu_requested = 0 
33      """Number of CPU hours requested in this domain""" 
34      cpu_used = 0 
35      """Number of CPU hours used in this domain""" 
36      last_credit = 0 
37      """timestamp of last credit""" 
38      @staticmethod 
39 -    def fetch(id): 
40          """ 
41          Fetch a resource domain from the database. 
42          """ 
43          usage=databaselookup(id) 
44          return usage 
45 -    def nice(self, points=1, cost=None): 
46          """ 
47          Purchase or sell nice points. 
48   
49          Users who let some jobs run at lower priority are rewarded by having 
50          other jobs run at higher priority.  To avoid too much gaming of the 
51          system, the cost of the jobs must be estimated, based on number of 
52          cpu hours. 
53   
54          Raises ValueError if insufficient credit to raise the privilege. 
55          """ 
56          if self.credit >= 0: 
57              if points*cost<self.credit: 
58                  raise ValueError("Insufficient credit") 
59              self.credit -= points*cost 
60              databasestore(self) 
61 -    def requested(self, cost=None): 
62          """ 
63          Record the request. 
64   
65          Note that no request will be denied at this point.  By always 
66          allowing work to run we avoid under-utilizing the machine. 
67          """ 
68   
69 -class User(object): 
70      """ 
71      Information about the individual user. 
72   
73      This is mapped to a persistent store in the service database. 
74      """ 
75      domain = "" 
76      """ 
77      Domain to use for the user. 
78      """ 
79      name = "" 
80      """Screen name for the user.  This is for convenience and need not 
81      be unique.  The real identiy is the user id and the associated 
82      authentication key.""" 
83      key = "" 
84      """Authentication key used to uniquely identify the user.  This should 
85      be the public key portion of a public-private pair, or the key hash 
86      for secure remote password.""" 
87      password = "" 
88      """Password for logging into the service without a public key.""" 
89