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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
|
"""
SleekXMPP: The Sleek XMPP Library
Implementation of xeps for Internet of Things
http://wiki.xmpp.org/web/Tech_pages/IoT_systems
Copyright (C) 2013 Sustainable Innovation, Joachim.lindborg@sust.se, bjorn.westrom@consoden.se
This file is part of SleekXMPP.
See the file LICENSE for copying permission.
"""
import datetime
import logging
class Device(object):
"""
Example implementation of a device readout object.
Is registered in the XEP_0323.register_node call
The device object may be any custom implementation to support
specific devices, but it must implement the functions:
has_field
request_fields
"""
def __init__(self, nodeId, fields={}):
self.nodeId = nodeId
self.fields = fields # see fields described below
# {'type':'numeric',
# 'name':'myname',
# 'value': 42,
# 'unit':'Z'}];
self.timestamp_data = {}
self.momentary_data = {}
self.momentary_timestamp = ""
logging.debug("Device object started nodeId %s",nodeId)
def has_field(self, field):
"""
Returns true if the supplied field name exists in this device.
Arguments:
field -- The field name
"""
if field in self.fields.keys():
return True;
return False;
def refresh(self, fields):
"""
override method to do the refresh work
refresh values from hardware or other
"""
pass
def request_fields(self, fields, flags, session, callback):
"""
Starts a data readout. Verifies the requested fields,
refreshes the data (if needed) and calls the callback
with requested data.
Arguments:
fields -- List of field names to readout
flags -- [optional] data classifier flags for the field, e.g. momentary
Formatted as a dictionary like { "flag name": "flag value" ... }
session -- Session id, only used in the callback as identifier
callback -- Callback function to call when data is available.
The callback function must support the following arguments:
session -- Session id, as supplied in the request_fields call
nodeId -- Identifier for this device
result -- The current result status of the readout. Valid values are:
"error" - Readout failed.
"fields" - Contains readout data.
"done" - Indicates that the readout is complete. May contain
readout data.
timestamp_block -- [optional] Only applies when result != "error"
The readout data. Structured as a dictionary:
{
timestamp: timestamp for this datablock,
fields: list of field dictionary (one per readout field).
readout field dictionary format:
{
type: The field type (numeric, boolean, dateTime, timeSpan, string, enum)
name: The field name
value: The field value
unit: The unit of the field. Only applies to type numeric.
dataType: The datatype of the field. Only applies to type enum.
flags: [optional] data classifier flags for the field, e.g. momentary
Formatted as a dictionary like { "flag name": "flag value" ... }
}
}
error_msg -- [optional] Only applies when result == "error".
Error details when a request failed.
"""
logging.debug("request_fields called looking for fields %s",fields)
if len(fields) > 0:
# Check availiability
for f in fields:
if f not in self.fields.keys():
self._send_reject(session, callback)
return False;
else:
# Request all fields
fields = self.fields.keys();
# Refresh data from device
# ...
logging.debug("about to refresh device fields %s",fields)
self.refresh(fields)
if "momentary" in flags and flags['momentary'] == "true" or \
"all" in flags and flags['all'] == "true":
ts_block = {};
timestamp = "";
if len(self.momentary_timestamp) > 0:
timestamp = self.momentary_timestamp;
else:
timestamp = self._get_timestamp();
field_block = [];
for f in self.momentary_data:
if f in fields:
field_block.append({"name": f,
"type": self.fields[f]["type"],
"unit": self.fields[f]["unit"],
"dataType": self.fields[f]["dataType"],
"value": self.momentary_data[f]["value"],
"flags": self.momentary_data[f]["flags"]});
ts_block["timestamp"] = timestamp;
ts_block["fields"] = field_block;
callback(session, result="done", nodeId=self.nodeId, timestamp_block=ts_block);
return
from_flag = self._datetime_flag_parser(flags, 'from')
to_flag = self._datetime_flag_parser(flags, 'to')
for ts in sorted(self.timestamp_data.keys()):
tsdt = datetime.datetime.strptime(ts, "%Y-%m-%dT%H:%M:%S")
if not from_flag is None:
if tsdt < from_flag:
#print (str(tsdt) + " < " + str(from_flag))
continue
if not to_flag is None:
if tsdt > to_flag:
#print (str(tsdt) + " > " + str(to_flag))
continue
ts_block = {};
field_block = [];
for f in self.timestamp_data[ts]:
if f in fields:
field_block.append({"name": f,
"type": self.fields[f]["type"],
"unit": self.fields[f]["unit"],
"dataType": self.fields[f]["dataType"],
"value": self.timestamp_data[ts][f]["value"],
"flags": self.timestamp_data[ts][f]["flags"]});
ts_block["timestamp"] = ts;
ts_block["fields"] = field_block;
callback(session, result="fields", nodeId=self.nodeId, timestamp_block=ts_block);
callback(session, result="done", nodeId=self.nodeId, timestamp_block=None);
def _datetime_flag_parser(self, flags, flagname):
if not flagname in flags:
return None
dt = None
try:
dt = datetime.datetime.strptime(flags[flagname], "%Y-%m-%dT%H:%M:%S")
except ValueError:
# Badly formatted datetime, ignore it
pass
return dt
def _get_timestamp(self):
"""
Generates a properly formatted timestamp of current time
"""
return datetime.datetime.now().replace(microsecond=0).isoformat()
def _send_reject(self, session, callback):
"""
Sends a reject to the caller
Arguments:
session -- Session id, see definition in request_fields function
callback -- Callback function, see definition in request_fields function
"""
callback(session, result="error", nodeId=self.nodeId, timestamp_block=None, error_msg="Reject");
def _add_field(self, name, typename, unit=None, dataType=None):
"""
Adds a field to the device
Arguments:
name -- Name of the field
typename -- Type of the field (numeric, boolean, dateTime, timeSpan, string, enum)
unit -- [optional] only applies to "numeric". Unit for the field.
dataType -- [optional] only applies to "enum". Datatype for the field.
"""
self.fields[name] = {"type": typename, "unit": unit, "dataType": dataType};
def _add_field_timestamp_data(self, name, timestamp, value, flags=None):
"""
Adds timestamped data to a field
Arguments:
name -- Name of the field
timestamp -- Timestamp for the data (string)
value -- Field value at the timestamp
flags -- [optional] data classifier flags for the field, e.g. momentary
Formatted as a dictionary like { "flag name": "flag value" ... }
"""
if not name in self.fields.keys():
return False;
if not timestamp in self.timestamp_data:
self.timestamp_data[timestamp] = {};
self.timestamp_data[timestamp][name] = {"value": value, "flags": flags};
return True;
def _add_field_momentary_data(self, name, value, flags=None):
"""
Sets momentary data to a field
Arguments:
name -- Name of the field
value -- Field value at the timestamp
flags -- [optional] data classifier flags for the field, e.g. momentary
Formatted as a dictionary like { "flag name": "flag value" ... }
"""
if not self.fields.has_key(name):
return False;
if flags is None:
flags = {};
flags["momentary"] = "true"
self.momentary_data[name] = {"value": value, "flags": flags};
return True;
def _set_momentary_timestamp(self, timestamp):
"""
This function is only for unit testing to produce predictable results.
"""
self.momentary_timestamp = timestamp;
|