Coverage for arrakis_server/channel.py: 90.5%

1# Copyright (c) 2025, California Institute of Technology and contributors 

2# 

3# You should have received a copy of the licensing terms for this 

4# software included in the file "LICENSE" located in the top-level 

5# directory of this package. If you did not, you can view a copy at 

6# https://git.ligo.org/ngdd/arrakis-python/-/raw/main/LICENSE 

7 

8"""Server-specific channel information.""" 

9 

10from __future__ import annotations 

11 

12from dataclasses import dataclass 

13from functools import cached_property 

14 

15from arrakis.channel import Channel as BaseChannel 

16 

17 

18@dataclass(frozen=True, order=True) 

19class Channel(BaseChannel): 

20 """Metadata associated with a channel. 

21 

22 Channels have the form {domain}:{subsystem}-*. 

23 

24 Parameters 

25 ---------- 

26 name : str 

27 The name associated with this channel. 

28 data_type : numpy.dtype 

29 The data type associated with this channel. 

30 sample_rate : float 

31 The sampling rate associated with this channel. 

32 time : int, optional 

33 The timestamp when this metadata became active. 

34 publisher : str 

35 The publisher associated with this channel. 

36 partition_id : str, optional 

37 The partition ID associated with this channel. 

38 expected_latency: int, optional 

39 Expected publication latency for this channel's data, in 

40 seconds. 

41 

42 """ 

43 

44 def validate(self) -> None: 

45 components = self.name.split(":") 

46 if len(components) != 2 or "-" not in self.name: 

47 raise ValueError( 

48 "channel is malformed, needs to be in the form {domain}:{subsystem}-*" 

49 ) 

50 

51 @cached_property 

52 def subsystem(self) -> str: 

53 """The subsystem associated with a given channel.""" 

54 _, rest = self.name.split(":") 

55 return rest.split("-")[0] 

56 

57 

58def extract_channel_scope(channel: str) -> tuple[str, str]: 

59 """Given a channel name, extracts the channel's scope. 

60 

61 Parameters 

62 ---------- 

63 channel : str 

64 The channel with the form {domain}:{subsystem}-*. 

65 

66 Returns 

67 ------- 

68 tuple[str, str] 

69 The domain and the subsystem, respectively. 

70 """ 

71 components = channel.split(":") 

72 if len(components) != 2 or "-" not in channel: 

73 raise ValueError( 

74 "channel is malformed, needs to be in the form {domain}:{subsystem}-*" 

75 ) 

76 

77 domain, rest = components 

78 subsystem = rest.split("-")[0] 

79 

80 return domain, subsystem