1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
DEFAULT_TASK_MAX_DURATION = 36000
module OpenTox
# Class for handling asynchronous tasks
class Task
attr_accessor :pid, :observer_pid
def self.create service_uri, params={}
uri = RDF::URI.new File.join(service_uri,SecureRandom.uuid)
#uri = RestClientWrapper.post service_uri
#puts uri
task = Task.new uri
#task.pull
#puts task.to_turtle
task.rdf << RDF::Statement.new(uri, RDF.type, RDF::OT.Task)
task.rdf << RDF::Statement.new(uri, RDF::DC.date, RDF::Literal.new(DateTime.now))
task.rdf << RDF::Statement.new(uri, RDF::OT.hasStatus, RDF::Literal.new("Running"))
params.each {|k,v| task.rdf << RDF::Statement.new(uri, k, v)}
task.save
pid = fork do
begin
result_uri = yield
task.completed result_uri
rescue
if $!.respond_to? :to_ntriples
RestClientWrapper.put(File.join(task.uri,'Error'),:errorReport => $!.to_ntriples,:content_type => 'text/plain')
else
RestClientWrapper.put(File.join(task.uri,'Error')) #if $!.respond_to? :report
end
task.kill
end
end
Process.detach(pid)
task.pid = pid
# watch if task has been cancelled
observer_pid = fork do
task.wait
begin
Process.kill(9,task.pid) if task.cancelled?
rescue
$logger.warn "Could not kill process of task #{task.uri}, pid: #{task.pid}"
end
end
Process.detach(observer_pid)
task.observer_pid = observer_pid
task
end
def kill
Process.kill(9,@pid)
Process.kill(9,@observer_pid)
rescue # no need to raise an exeption if processes are not running
end
def description
pull
self.[](RDF::DC.description).uniq.first
end
def creator
pull
self.[](RDF::DC.creator).uniq.first
end
def cancel
kill
RestClientWrapper.put(File.join(@uri,'Cancelled'),{})
end
def completed(uri)
#TODO fix for https rewrites
not_found_error "Result URI \"#{uri}\" does not exist." unless URI.accessible? uri
RestClientWrapper.put(File.join(@uri,'Completed'),{:resultURI => uri})
end
# waits for a task, unless time exceeds or state is no longer running
# @param [optional,Numeric] dur seconds pausing before checking again for completion
# TODO: add waiting task
def wait
start_time = Time.new
due_to_time = start_time + DEFAULT_TASK_MAX_DURATION
dur = 0.3
while running?
sleep dur
dur = [[(Time.new - start_time)/20.0,0.3].max,300.0].min
time_out_error "max wait time exceeded ("+DEFAULT_TASK_MAX_DURATION.to_s+"sec), task: '"+@uri.to_s+"'" if (Time.new > due_to_time)
end
end
end
# get only header for status requests
def running?
RestClientWrapper.head(@uri).code == 202
end
def cancelled?
RestClientWrapper.head(@uri).code == 503
end
def completed?
RestClientWrapper.head(@uri).code == 200
end
def error?
code = RestClientWrapper.head(@uri).code
code >= 400 and code != 503
end
def errorReport
# TODO: fix rdf output at task service
not_implemented_error "RDF output of errorReports has to be fixed at task service"
end
[:hasStatus, :resultURI].each do |method|
define_method method do
response = self.[](RDF::OT[method])
response = self.[](RDF::OT1[method]) unless response # API 1.1 compatibility
response
end
end
#TODO: subtasks (only for progress)
end
|
