def field_spec_getter(msg_reg, chan):
# we have already read the header containing the field number
# read the byte count, the length of the spec
byte_count = read_raw_varint(chan)
end = chan.position + byte_count
# read field 0
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
string = read_raw_len_plus(chan)
name = string.decode('utf-8') # convert bytes to str
# read field 1
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
field_type = VENUM_GET(chan)
# read field 2
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
quant = VENUM_GET(chan)
# read field 3
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
f_nbr = VENUM_GET(chan)
# XXX IGNORING DEFAULT
default = None
val = FieldSpec(msg_reg, name, field_type, quant, f_nbr, default)
return val
def enum_spec_getter(dummy_reg, chan):
# we have already read the header containing the field number
# read the byte count, the length of the spec
byte_count = read_raw_varint(chan)
end = chan.position + byte_count # XXX should use for validation
# read field 0
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
string = read_raw_len_plus(chan)
name = string.decode('utf-8') # convert bytes to str
# read instances of field 1: should enforce the + quantifier here
pairs = []
while chan.position < end:
hdr = read_raw_varint(chan)
if hdr_field_nbr(hdr) != 1:
# XXX SHOULD COMPLAIN IF WRONG HEADER
# XXX This is a a peek: pos only gets advanced if OK
print("EXPECTED FIELD 1, FOUND %s" % hdr_field_nbr(hdr))
break
exc = enum_pair_spec_getter(dummy_reg, chan)
pairs.append(exc)
# create EnumSpec instance, which gets returned
val = EnumSpec(name, pairs)
return val
def round_trip(self, nnn):
"""
Test writing and reading a varint as the first and
only field in a buffer.
"""
# -- write varint -------------------------------------------
field_nbr = 1 + self.rng.next_int16(1024)
chan = Channel(LEN_BUFFER)
write_varint_field(chan, nnn, field_nbr)
chan.flip()
# -- read varint --------------------------------------------
# first the header (which is a varint) ------------
(prim_type, field_nbr2) = read_field_hdr(chan)
offset2 = chan.position
self.assertEqual(PrimTypes.VARINT, prim_type)
self.assertEqual(field_nbr, field_nbr2)
self.assertEqual(length_as_varint(field_nbr << 3), offset2)
# then the varint proper --------------------------
varint_ = read_raw_varint(chan)
chan.flip()
offset3 = chan.limit
self.assertEqual(nnn, varint_)
self.assertEqual(offset2 + length_as_varint(nnn), offset3)
def enum_pair_spec_getter(dummy_reg, chan):
# we have already read the header containing the field number
# read the byte count, the length of the spec
byte_count = read_raw_varint(chan)
end = chan.position + byte_count # XXX should use for validation
# read field 0
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
string = read_raw_len_plus(chan)
sym = string.decode('utf-8') # convert bytes to str
# read field 1
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
val = read_raw_varint(chan)
# construct the EnumPairSpec object from field values
obj = EnumPairSpec(sym, val)
return obj
def msg_spec_getter(msg_reg, chan):
# read the byte count, the length of the spec
byte_count = read_raw_varint(chan)
end = chan.position + byte_count
# read field 0
hdr = read_raw_varint(chan)
# SHOULD COMPLAIN IF WRONG HEADER
string = read_raw_len_plus(chan)
name = string.decode('utf8') # convert byte to str
# read instances of field 1: should enforce the + quantifier here
fields = []
while chan.position < end:
hdr = read_raw_varint(chan)
if hdr_field_nbr(hdr) != 1:
# XXX SHOULD COMPLAIN IF WRONG HEADER
# XXX This is a a peek: pos only gets advanced if OK
print("EXPECTED FIELD 1, FOUND %s" % hdr_field_nbr(hdr))
break
# XXX params should be (msgReg, chan)
file = field_spec_getter(msg_reg, chan) # was chan0
fields.append(file)
# we may have multiple enums
enums = []
while chan.position < end:
hdr = read_raw_varint(chan)
if hdr_field_nbr(hdr) != 2:
print("EXPECTED FIELD 2, FOUND %s" % hdr_field_nbr(hdr))
break
enum = enum_spec_getter(chan) # was chan0
enums.append(enum)
# XXX WRONG PARAMETER LIST
# val = MsgSpec(name, fields, enums)
dummy_parent = MsgSpec('dummy', msg_reg, None)
val = MsgSpec(name, msg_reg, dummy_parent)
return val
def recv_from_cnx(cnx, chan):
"""
Receive a serialized message from a connection into a channel.
On return the channel has been flipped (offset = 0, limit =
data length). Returns the msgNbr.
"""
# ---------------------------------------------------------------
# SEE fieldz.msgImpl for an example of this kind of Channel
# manipulation. Use a Python buffer to select the region of the
# buffer we want to write into.
# ---------------------------------------------------------------
# receive something from the connection
chan.clear()
count = cnx.recv_into(chan.buffer, BUFSIZE)
if count <= 0:
raise IOError('initial read of message gets zero bytes')
# read the header to determine the message type and its length
(p_type, msg_nbr) = read_field_hdr(chan)
# DEBUG
print("CHAN_IO: count = %d; pType = %s, msgNbr = %s" %
(count, p_type, msg_nbr))
# END
if p_type != PrimTypes.LEN_PLUS:
raise IOError('message header type is %d, not PrimTypes.LEN_PLUS' %
p_type)
# XXX raise exception of msgNbr <0 or msgNbr > 2
msg_len = read_raw_varint(chan)
# XXX ignoring pathological possibility that offset > count
# if we don't have all of the data, loop getting the rest
while count < msg_len:
# vBuf = buffer(chan.buffer, count)
v_buf = memoryview(chan.buffer)[count:]
count += cnx.recv_into(v_buf, BUFSIZE - count)
chan.position = count
chan.flip()
return msg_nbr
def vsint64_get(chan):
varint_ = read_raw_varint(chan)
return decode_sint64(varint_)
def vuint64_get(chan):
return read_raw_varint(chan)
def vbool_get(chan):
varint_ = read_raw_varint(chan)
return bool(varint_)
def venum_get(chan):
return read_raw_varint(chan)
def read(cls, chan, parent_spec):
"""msg refers to the msg, n is field number; returns msg, n"""
(p_type, nnn) = read_field_hdr(chan)
if nnn < 0 or nnn >= len(parent_spec.msgs):
raise RuntimeError("msg ID '%s' out of range" % nnn)
msg_spec = parent_spec.msgs[nnn]
msg_len = read_raw_varint(chan)
# DEBUG
print("IMPL_GETTER, P_TYPE %d, MSG/FIELD NBR %d, MSG_LEN %d" % (
p_type, nnn, msg_len))
# END
end = chan.position + msg_len
cls = _make_msg_class(parent_spec, msg_spec) # generated class
fields = [] # ???
values = [] # ???
# XXX THIS IS NOT GOING TO WORK, BECAUSE WE NEED TO PEEK XXX
for f_class in cls._fieldClasses:
field_type = f_class._field_type # a number
f_quant = f_class._quantifier
field_nbr = f_class._field_nbr
# read the field header
(p_type, nbr) = read_field_hdr(chan)
# DEBUG
print(
" GET_FROM_CHAN, FIELD %u, TYPE %u" %
(field_nbr, field_type))
# END
if field_nbr != nbr:
raise RuntimeError(" EXPECTED FIELD_NBR %d, GOT %d" % (
field_nbr, nbr))
if f_quant == Q_REQUIRED or f_quant == Q_OPTIONAL:
if field_type > 23:
reg = cls.msg_spec.reg
# BEGIN JUNK ------------------------------------
# DEBUG
print(
"READING: FIELD TYPE IS %s" %
reg.reg_id2name(field_type))
# END
entry = reg.reg_id2entry(field_type)
print("READING: FIELD TYPE bis IS %s" % entry.name)
# END JUNK --------------------------------------
child_spec = entry.msg_spec
child_class = _make_msg_class(msg_spec, child_spec)
# RECURSE: read(childCls, chan, msgSpec)
# msgSpec is parentSpec here
value = T_GET_FUNCS[field_type](chan) # XXX WRONG
else:
value = T_GET_FUNCS[field_type](chan)
_check_position(chan, end)
values.append(value)
elif f_quant == Q_PLUS or f_quant == Q_STAR:
v_list = [] # we are reading a list of values
# WORKING HERE
else:
raise RuntimeError("unknown quantifier, index '%u'" % f_quant)
# DEBUG
print("AFTER COLLECTING %u FIELDS, OFFSET IS %u" % (
len(fields), chan.position))
# END
# XXX BLOWS UP: can't handle Q_PLUS or Q_STAR (about line 407)
return (cls(values), nnn) # GEEP
