4 # Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com> |
4 # Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com> |
5 # |
5 # |
6 # This software may be used and distributed according to the terms of the |
6 # This software may be used and distributed according to the terms of the |
7 # GNU General Public License version 2 or any later version. |
7 # GNU General Public License version 2 or any later version. |
8 |
8 |
9 from i18n import _ |
9 from __future__ import absolute_import |
10 import error |
10 |
|
11 from .i18n import _ |
|
12 from . import ( |
|
13 error, |
|
14 util, |
|
15 ) |
|
16 |
|
17 # abstract batching support |
|
18 |
|
19 class future(object): |
|
20 '''placeholder for a value to be set later''' |
|
21 def set(self, value): |
|
22 if util.safehasattr(self, 'value'): |
|
23 raise error.RepoError("future is already set") |
|
24 self.value = value |
|
25 |
|
26 class batcher(object): |
|
27 '''base class for batches of commands submittable in a single request |
|
28 |
|
29 All methods invoked on instances of this class are simply queued and |
|
30 return a a future for the result. Once you call submit(), all the queued |
|
31 calls are performed and the results set in their respective futures. |
|
32 ''' |
|
33 def __init__(self): |
|
34 self.calls = [] |
|
35 def __getattr__(self, name): |
|
36 def call(*args, **opts): |
|
37 resref = future() |
|
38 self.calls.append((name, args, opts, resref,)) |
|
39 return resref |
|
40 return call |
|
41 def submit(self): |
|
42 pass |
|
43 |
|
44 class localbatch(batcher): |
|
45 '''performs the queued calls directly''' |
|
46 def __init__(self, local): |
|
47 batcher.__init__(self) |
|
48 self.local = local |
|
49 def submit(self): |
|
50 for name, args, opts, resref in self.calls: |
|
51 resref.set(getattr(self.local, name)(*args, **opts)) |
|
52 |
|
53 def batchable(f): |
|
54 '''annotation for batchable methods |
|
55 |
|
56 Such methods must implement a coroutine as follows: |
|
57 |
|
58 @batchable |
|
59 def sample(self, one, two=None): |
|
60 # Handle locally computable results first: |
|
61 if not one: |
|
62 yield "a local result", None |
|
63 # Build list of encoded arguments suitable for your wire protocol: |
|
64 encargs = [('one', encode(one),), ('two', encode(two),)] |
|
65 # Create future for injection of encoded result: |
|
66 encresref = future() |
|
67 # Return encoded arguments and future: |
|
68 yield encargs, encresref |
|
69 # Assuming the future to be filled with the result from the batched |
|
70 # request now. Decode it: |
|
71 yield decode(encresref.value) |
|
72 |
|
73 The decorator returns a function which wraps this coroutine as a plain |
|
74 method, but adds the original method as an attribute called "batchable", |
|
75 which is used by remotebatch to split the call into separate encoding and |
|
76 decoding phases. |
|
77 ''' |
|
78 def plain(*args, **opts): |
|
79 batchable = f(*args, **opts) |
|
80 encargsorres, encresref = batchable.next() |
|
81 if not encresref: |
|
82 return encargsorres # a local result in this case |
|
83 self = args[0] |
|
84 encresref.set(self._submitone(f.func_name, encargsorres)) |
|
85 return batchable.next() |
|
86 setattr(plain, 'batchable', f) |
|
87 return plain |
11 |
88 |
12 class peerrepository(object): |
89 class peerrepository(object): |
|
90 |
|
91 def batch(self): |
|
92 return localbatch(self) |
13 |
93 |
14 def capable(self, name): |
94 def capable(self, name): |
15 '''tell whether repo supports named capability. |
95 '''tell whether repo supports named capability. |
16 return False if not supported. |
96 return False if not supported. |
17 if boolean capability, return True. |
97 if boolean capability, return True. |