def _n_from_marker_numbers(self, tytup, item, topic, date_time, n,
throw_if_data_lost):
nums = (tytup[1] * n)()
dts = (_DateTimeStamp * n)()
g = _long_()
_lib_call("TOSDB_GetN" + tytup[0] + "sFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
nums,
n,
dts if date_time else _PTR_(_DateTimeStamp)(),
_pointer(g),
arg_types=(_str_, _str_, _str_, _PTR_(tytup[1]), _uint32_,
_PTR_(_DateTimeStamp), _PTR_(_long_)))
g = g.value
if g == 0:
return None
elif g < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
g *= -1
return list(zip(nums[:g], _map_dt(dts[:g])) if date_time else nums[:g])
def _n_from_marker_strings(self, item, topic, date_time, n,
throw_if_data_lost, data_str_max):
strs = _gen_str_buffers(data_str_max + 1, n)
pstrs = _gen_str_buffers_ptrs(strs)
dts = (_DateTimeStamp * n)()
g = _long_()
_lib_call("TOSDB_GetNStringsFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
pstrs,
n,
data_str_max + 1,
dts if date_time else _PTR_(_DateTimeStamp)(),
_pointer(g),
arg_types=(_str_, _str_, _str_, _ppchar_, _uint32_, _uint32_,
_PTR_(_DateTimeStamp), _PTR_(_long_)))
g = g.value
if g == 0:
return None
elif g < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
g *= -1
return list(
_zip_cstr_dt(pstrs[:g], dts[:g]
) if date_time else _map_cstr(pstrs[:g]))
def stream_snapshot_from_marker(self,
item,
topic,
date_time=False,
beg=0,
margin_of_safety=100,
throw_if_data_lost=True,
data_str_max=STR_DATA_SZ):
item = item.upper()
topic = topic.upper()
if date_time and not self._date_time:
raise TOSDB_DateTimeError("date_time not available for this block")
self._valid_item(item)
self._valid_topic(topic)
if beg < 0:
beg += self._block_size
if beg < 0 or beg >= self._block_size:
raise TOSDB_IndexError("invalid 'beg' index value")
if margin_of_safety < MIN_MARGIN_OF_SAFETY:
raise TOSDB_ValueError("margin_of_safety < MIN_MARGIN_OF_SAFETY")
is_dirty = _uint_()
_lib_call("TOSDB_IsMarkerDirty",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(is_dirty),
arg_types=(_str_, _str_, _str_, _PTR_(_uint_)))
if is_dirty and throw_if_data_lost:
raise TOSDB_DataError("marker is already dirty")
mpos = _longlong_()
_lib_call("TOSDB_GetMarkerPosition",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(mpos),
arg_types=(_str_, _str_, _str_, _PTR_(_longlong_)))
cur_sz = mpos.value - beg + 1
if cur_sz < 0:
return None
safe_sz = cur_sz + margin_of_safety
dtss = (_DateTimeStamp * safe_sz)()
tbits = type_bits(topic)
tytup = _type_switch(tbits)
get_size = _long_()
if tytup[0] == "String":
strs = [_BUF_(data_str_max + 1) for _ in range(safe_sz)]
strs_array = (_pchar_ *
safe_sz)(*[_cast(s, _pchar_) for s in strs])
_lib_call("TOSDB_GetStreamSnapshotStringsFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
strs_array,
safe_sz,
data_str_max + 1,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer(get_size),
arg_types=(_str_, _str_, _str_, _ppchar_, _uint32_,
_uint32_, _PTR_(_DateTimeStamp), _long_,
_PTR_(_long_)))
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [
sd for sd in zip(map(_cast_cstr, strs_array[:get_size]),
adj_dts)
]
else:
return [_cast_cstr(s) for s in strs_array[:get_size]]
else:
num_array = (tytup[1] * safe_sz)()
_lib_call("TOSDB_GetStreamSnapshot" + tytup[0] + "sFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
num_array,
safe_sz,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer(get_size),
arg_types=(_str_, _str_, _str_, _PTR_(tytup[1]),
_uint32_, _PTR_(_DateTimeStamp), _long_,
_PTR_(_long_)))
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [nd for nd in zip(num_array[:get_size], adj_dts)]
else:
return [n for n in num_array[:get_size]]
def stream_snapshot_from_marker(self, item, topic, date_time=False, beg=0,
margin_of_safety=100, throw_if_data_lost=True,
data_str_max=STR_DATA_SZ):
item = item.upper()
topic = topic.upper()
if date_time and not self._date_time:
raise TOSDB_DateTimeError("date_time not available for this block")
self._valid_item(item)
self._valid_topic(topic)
if beg < 0:
beg += self._block_size
if beg < 0 or beg >= self._block_size:
raise TOSDB_IndexError("invalid 'beg' index value")
if margin_of_safety < MIN_MARGIN_OF_SAFETY:
raise TOSDB_ValueError("margin_of_safety < MIN_MARGIN_OF_SAFETY")
is_dirty = _uint_()
_lib_call("TOSDB_IsMarkerDirty",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(is_dirty),
arg_types=(_str_, _str_, _str_, _PTR_(_uint_)))
if is_dirty and throw_if_data_lost:
raise TOSDB_DataError("marker is already dirty")
mpos = _longlong_()
_lib_call("TOSDB_GetMarkerPosition",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(mpos),
arg_types=(_str_, _str_, _str_, _PTR_(_longlong_)))
cur_sz = mpos.value - beg + 1
if cur_sz < 0:
return None
safe_sz = cur_sz + margin_of_safety
dtss = (_DateTimeStamp * safe_sz)()
tbits = type_bits(topic)
tytup = _type_switch(tbits)
get_size = _long_()
if tytup[0] == "String":
strs = [ _BUF_( data_str_max +1) for _ in range(safe_sz) ]
strs_array = (_pchar_ * safe_sz)(*[_cast(s,_pchar_) for s in strs])
_lib_call("TOSDB_GetStreamSnapshotStringsFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
strs_array,
safe_sz,
data_str_max + 1,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer(get_size),
arg_types=(_str_, _str_, _str_, _ppchar_, _uint32_, _uint32_,
_PTR_(_DateTimeStamp), _long_, _PTR_(_long_)))
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [sd for sd in zip(map(_cast_cstr, strs_array[:get_size]), adj_dts)]
else:
return [_cast_cstr(s) for s in strs_array[:get_size]]
else:
num_array = (tytup[1] * safe_sz)()
_lib_call("TOSDB_GetStreamSnapshot" + tytup[0] + "sFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
num_array,
safe_sz,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer(get_size),
arg_types=(_str_, _str_, _str_, _PTR_(tytup[1]), _uint32_,
_PTR_(_DateTimeStamp), _long_, _PTR_(_long_)))
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [nd for nd in zip(num_array[:get_size], adj_dts)]
else:
return [n for n in num_array[:get_size]]
def stream_snapshot_from_marker( self, item, topic, date_time = False,
beg = 0, margin_of_safety = 100,
throw_if_data_lost = True,
data_str_max = STR_DATA_SZ ):
""" Return multiple data-points(a snapshot) from the data-stream,
ending where the last call began
It's likely the stream will grow between consecutive calls. This call
guarantees to pick up where the last get(), stream_snapshot(), or
stream_snapshot_from_marker() call ended (under a few assumptions, see
below).
Internally the stream maintains a 'marker' that tracks the position of
the last value pulled; the act of retreiving data and moving the
marker can be thought of as a single, 'atomic' operation.
There are three states to be aware of:
1) a 'beg' value that is greater than the marker (even if beg = 0)
2) a marker that moves through the entire stream and hits the bound
3) passing a buffer that is too small for the whole range
State (1) can be caused by passing in a beginning index that is past
the current marker, or by passing in 0 when the marker has yet to
move. 'None' will be returned.
State (2) occurs when the marker doesn't get reset before it hits the
bound (block_size); as the oldest data is popped of the back of the
stream it is lost (the marker can't grow past the end of the stream).
State (3) occurs when an inadequately small buffer is used. The call
handles buffer sizing for you by calling down to get the marker index,
adjusting by 'beg' and 'margin_of_safety'. The latter helps assure the
marker doesn't outgrow the buffer by the time the low-level retrieval
operation completes. The default value indicates that over 100 push
operations would have to take place during this call(highly unlikely).
In either case (state (2) or (3)) if throw_if_data_lost is True a
TOSDB_DataError will be thrown, otherwise the available data will
be returned as normal.
item: any item string in the block
topic: any topic string in the block
date_time: (True/False) attempt to retrieve a TOSDB_DateTime object
beg: index of most recent data-point ( beginning of the snapshot )
margin_of_safety: (True/False) error margin for async stream growth
throw_if_data_loss: (True/False) how to handle error states (see above)
data_str_max: the maximum length of string data returned
if beg > internal marker value: returns -> None
if date_time is True: returns-> list of 2tuple
else: returns -> list
"""
item = item.upper()
topic = topic.upper()
if date_time and not self._date_time:
raise TOSDB_DateTimeError("date_time not available for this block")
self._valid_item(item)
self._valid_topic(topic)
if beg < 0:
beg += self._block_size
if beg < 0 or beg >= self._block_size:
raise TOSDB_IndexError("invalid 'beg' index value")
if margin_of_safety < MIN_MARGIN_OF_SAFETY:
raise TOSDB_ValueError("margin_of_safety < MIN_MARGIN_OF_SAFETY")
is_dirty = _uint_()
err = _lib_call( "TOSDB_IsMarkerDirty",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(is_dirty),
arg_list = [ _str_, _str_, _str_, _PTR_(_uint_) ] )
if err:
raise TOSDB_CLibError( "error value [ "+ str(err) + " ] " +
"returned from library call",
"TOSDB_IsMarkerDirty" )
if is_dirty and throw_if_data_lost:
raise TOSDB_DataError("marker is already dirty")
mpos = _longlong_()
err2 = _lib_call( "TOSDB_GetMarkerPosition",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(mpos),
arg_list = [ _str_, _str_, _str_, _PTR_(_longlong_) ])
if err2:
raise TOSDB_CLibError( "error value [ "+ str(err2) + " ] " +
"returned from library call",
"TOSDB_GetMarkerPosition" )
cur_sz = mpos.value - beg + 1
if cur_sz < 0:
return None
safe_sz = cur_sz + margin_of_safety
dtss = (_DateTimeStamp * safe_sz)()
tbits = type_bits( topic )
tytup = _type_switch( tbits )
get_size = _long_()
if tytup[0] == "String":
# store char buffers
strs = [ _BUF_( data_str_max +1 ) for _ in range(safe_sz) ]
# cast char buffers into (char*)[ ]
strs_array = (_pchar_ * safe_sz)(*[ cast(s,_pchar_) for s in strs])
err3 = _lib_call( "TOSDB_GetStreamSnapshotStringsFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
strs_array,
safe_sz,
data_str_max + 1,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer( get_size ),
arg_list = [ _str_, _str_, _str_, _ppchar_,
_ulong_, _ulong_,
_PTR_(_DateTimeStamp), _long_,
_PTR_(_long_) ] )
if err3:
raise TOSDB_CLibError( "error value [ " + str(err3) +
" ] returned from library call",
"TOSDB_GetStreamSnapshotStrings" \
+ "FromMarker")
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [ TOSDB_DateTime( x ) for x in dtss[:get_size] ]
return [ _ for _ in \
zip( map( lambda x : cast(x, _str_).value.decode(),
strs_array[:get_size] ), adj_dts ) ]
else:
return [ cast(ptr,_str_).value.decode()
for ptr in strs_array[:get_size] ]
else:
num_array = (tytup[1] * safe_sz)()
err3 = _lib_call( "TOSDB_GetStreamSnapshot" \
+ tytup[0] + "sFromMarker" ,
self._name,
item.encode("ascii"),
topic.encode("ascii"),
num_array,
safe_sz,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer( get_size ),
arg_list = [ _str_, _str_, _str_,
_PTR_(tytup[1]), _ulong_,
_PTR_(_DateTimeStamp), _long_,
_PTR_(_long_) ] )
if err3:
raise TOSDB_CLibError( "error value of [ " + str(err3) +
" ] returned from library call",
"TOSDB_GetStreamSnapshot" \
+ tytup[0] + "sFromMarker" )
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [ TOSDB_DateTime( x ) for x in dtss[:get_size] ]
return [ _ for _ in zip( num_array[:get_size], adj_dts ) ]
else:
return [ _ for _ in num_array[:get_size] ]
def stream_snapshot_from_marker(self,
item,
topic,
date_time=False,
beg=0,
margin_of_safety=100,
throw_if_data_lost=True,
data_str_max=STR_DATA_SZ):
""" Return multiple data-points(a snapshot) from the data-stream,
ending where the last call began
It's likely the stream will grow between consecutive calls. This call
guarantees to pick up where the last get(), stream_snapshot(), or
stream_snapshot_from_marker() call ended (under a few assumptions, see
below).
Internally the stream maintains a 'marker' that tracks the position of
the last value pulled; the act of retreiving data and moving the
marker can be thought of as a single, 'atomic' operation.
There are three states to be aware of:
1) a 'beg' value that is greater than the marker (even if beg = 0)
2) a marker that moves through the entire stream and hits the bound
3) passing a buffer that is too small for the whole range
State (1) can be caused by passing in a beginning index that is past
the current marker, or by passing in 0 when the marker has yet to
move. 'None' will be returned.
State (2) occurs when the marker doesn't get reset before it hits the
bound (block_size); as the oldest data is popped of the back of the
stream it is lost (the marker can't grow past the end of the stream).
State (3) occurs when an inadequately small buffer is used. The call
handles buffer sizing for you by calling down to get the marker index,
adjusting by 'beg' and 'margin_of_safety'. The latter helps assure the
marker doesn't outgrow the buffer by the time the low-level retrieval
operation completes. The default value indicates that over 100 push
operations would have to take place during this call(highly unlikely).
In either case (state (2) or (3)) if throw_if_data_lost is True a
TOSDB_DataError will be thrown, otherwise the available data will
be returned as normal.
item: any item string in the block
topic: any topic string in the block
date_time: (True/False) attempt to retrieve a TOSDB_DateTime object
beg: index of most recent data-point ( beginning of the snapshot )
margin_of_safety: (True/False) error margin for async stream growth
throw_if_data_loss: (True/False) how to handle error states (see above)
data_str_max: the maximum length of string data returned
if beg > internal marker value: returns -> None
if date_time is True: returns-> list of 2tuple
else: returns -> list
"""
item = item.upper()
topic = topic.upper()
if date_time and not self._date_time:
raise TOSDB_DateTimeError("date_time not available for this block")
self._valid_item(item)
self._valid_topic(topic)
if beg < 0:
beg += self._block_size
if beg < 0 or beg >= self._block_size:
raise TOSDB_IndexError("invalid 'beg' index value")
if margin_of_safety < MIN_MARGIN_OF_SAFETY:
raise TOSDB_ValueError("margin_of_safety < MIN_MARGIN_OF_SAFETY")
is_dirty = _uint_()
err = _lib_call("TOSDB_IsMarkerDirty",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(is_dirty),
arg_list=[_str_, _str_, _str_,
_PTR_(_uint_)])
if err:
raise TOSDB_CLibError(
"error value [ " + str(err) + " ] " +
"returned from library call", "TOSDB_IsMarkerDirty")
if is_dirty and throw_if_data_lost:
raise TOSDB_DataError("marker is already dirty")
mpos = _longlong_()
err2 = _lib_call("TOSDB_GetMarkerPosition",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
_pointer(mpos),
arg_list=[_str_, _str_, _str_,
_PTR_(_longlong_)])
if err2:
raise TOSDB_CLibError(
"error value [ " + str(err2) + " ] " +
"returned from library call", "TOSDB_GetMarkerPosition")
cur_sz = mpos.value - beg + 1
if cur_sz < 0:
return None
safe_sz = cur_sz + margin_of_safety
dtss = (_DateTimeStamp * safe_sz)()
tbits = type_bits(topic)
tytup = _type_switch(tbits)
get_size = _long_()
if tytup[0] == "String":
# store char buffers
strs = [_BUF_(data_str_max + 1) for _ in range(safe_sz)]
# cast char buffers into (char*)[ ]
strs_array = (_pchar_ * safe_sz)(*[cast(s, _pchar_) for s in strs])
err3 = _lib_call("TOSDB_GetStreamSnapshotStringsFromMarker",
self._name,
item.encode("ascii"),
topic.encode("ascii"),
strs_array,
safe_sz,
data_str_max + 1,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer(get_size),
arg_list=[
_str_, _str_, _str_, _ppchar_, _ulong_,
_ulong_,
_PTR_(_DateTimeStamp), _long_,
_PTR_(_long_)
])
if err3:
raise TOSDB_CLibError( "error value [ " + str(err3) +
" ] returned from library call",
"TOSDB_GetStreamSnapshotStrings" \
+ "FromMarker")
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [ _ for _ in \
zip( map( lambda x : cast(x, _str_).value.decode(),
strs_array[:get_size] ), adj_dts ) ]
else:
return [
cast(ptr, _str_).value.decode()
for ptr in strs_array[:get_size]
]
else:
num_array = (tytup[1] * safe_sz)()
err3 = _lib_call( "TOSDB_GetStreamSnapshot" \
+ tytup[0] + "sFromMarker" ,
self._name,
item.encode("ascii"),
topic.encode("ascii"),
num_array,
safe_sz,
dtss if date_time else _PTR_(_DateTimeStamp)(),
beg,
_pointer( get_size ),
arg_list = [ _str_, _str_, _str_,
_PTR_(tytup[1]), _ulong_,
_PTR_(_DateTimeStamp), _long_,
_PTR_(_long_) ] )
if err3:
raise TOSDB_CLibError( "error value of [ " + str(err3) +
" ] returned from library call",
"TOSDB_GetStreamSnapshot" \
+ tytup[0] + "sFromMarker" )
get_size = get_size.value
if get_size == 0:
return None
elif get_size < 0:
if throw_if_data_lost:
raise TOSDB_DataError("data lost behind the 'marker'")
else:
get_size *= -1
if date_time:
adj_dts = [TOSDB_DateTime(x) for x in dtss[:get_size]]
return [_ for _ in zip(num_array[:get_size], adj_dts)]
else:
return [_ for _ in num_array[:get_size]]
