Coverage for python/lsst/sphgeom/_yaml.py: 63%

Shortcuts on this page

r m x p   toggle line displays

j k   next/prev highlighted chunk

0   (zero) top of page

1   (one) first highlighted chunk

42 statements  

1# This file is part of sphgeom. 

2# 

3# Developed for the LSST Data Management System. 

4# This product includes software developed by the LSST Project 

5# (http://www.lsst.org). 

6# See the COPYRIGHT file at the top-level directory of this distribution 

7# for details of code ownership. 

8# 

9# This program is free software: you can redistribute it and/or modify 

10# it under the terms of the GNU General Public License as published by 

11# the Free Software Foundation, either version 3 of the License, or 

12# (at your option) any later version. 

13# 

14# This program is distributed in the hope that it will be useful, 

15# but WITHOUT ANY WARRANTY; without even the implied warranty of 

16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 

17# GNU General Public License for more details. 

18# 

19# You should have received a copy of the GNU General Public License 

20# along with this program. If not, see <http://www.gnu.org/licenses/>. 

21 

22"""Add support for YAML serialization of regions.""" 

23 

24__all__ = () 

25 

26# YAML representers and constructors are only useful if yaml itself can 

27# be imported. If yaml can not be imported then there is no reason to 

28# break the entire module import of sphgeom. 

29try: 

30 import yaml 

31except ImportError: 

32 yaml = None 

33 

34from ._sphgeom import ( 

35 Box, 

36 Circle, 

37 ConvexPolygon, 

38 Ellipse, 

39 UnionRegion, 

40 IntersectionRegion, 

41 HtmPixelization, 

42 Mq3cPixelization, 

43 Region, 

44 Q3cPixelization, 

45) 

46 

47from ._healpixPixelization import HealpixPixelization 

48 

49 

50if yaml: 50 ↛ 64line 50 didn't jump to line 64, because the condition on line 50 was never false

51 try: 

52 # CLoader is not always available 

53 from yaml import CLoader 

54 except ImportError: 

55 CLoader = None 

56 

57 YamlLoaders = (yaml.Loader, yaml.FullLoader, yaml.SafeLoader, yaml.UnsafeLoader) 

58 if CLoader is not None: 58 ↛ 64line 58 didn't jump to line 64, because the condition on line 58 was never false

59 YamlLoaders += (CLoader,) 

60 

61 

62# Regions 

63 

64def region_representer(dumper, data): 

65 """Represent a sphgeom region object in a form suitable for YAML. 

66 

67 Stores the region as a mapping with a single ``encoded`` key 

68 storing the hex encoded byte string. 

69 """ 

70 encoded = data.encode() 

71 return dumper.represent_mapping(f"lsst.sphgeom.{type(data).__name__}", 

72 {"encoded": encoded.hex()}) 

73 

74 

75def region_constructor(loader, node): 

76 """Construct a sphgeom region from YAML""" 

77 mapping = loader.construct_mapping(node) 

78 encoded = bytes.fromhex(mapping["encoded"]) 

79 # The generic Region base class can instantiate a region of the 

80 # correct type. 

81 return Region.decode(encoded) 

82 

83 

84# Register all the region classes with the same constructor and representer 

85if yaml: 85 ↛ 95line 85 didn't jump to line 95, because the condition on line 85 was never false

86 for region_class in (ConvexPolygon, Ellipse, Circle, Box, UnionRegion, IntersectionRegion): 

87 yaml.add_representer(region_class, region_representer) 

88 

89 for loader in YamlLoaders: 

90 yaml.add_constructor(f"lsst.sphgeom.{region_class.__name__}", region_constructor, Loader=loader) 

91 

92 

93# Pixelization schemes 

94 

95def pixel_representer(dumper, data): 

96 """Represent a pixelization in YAML 

97 

98 Stored as the pixelization level in a mapping with a single key 

99 ``level``. 

100 """ 

101 return dumper.represent_mapping(f"lsst.sphgeom.{type(data).__name__}", 

102 {"level": data.getLevel()}) 

103 

104 

105def pixel_constructor(loader, node): 

106 """Construct a pixelization object from YAML. 

107 """ 

108 mapping = loader.construct_mapping(node) 

109 

110 className = node.tag 

111 pixelMap = {"lsst.sphgeom.Q3cPixelization": Q3cPixelization, 

112 "lsst.sphgeom.Mq3cPixelization": Mq3cPixelization, 

113 "lsst.sphgeom.HtmPixelization": HtmPixelization, 

114 "lsst.sphgeom.HealpixPixelization": HealpixPixelization, 

115 } 

116 

117 if className not in pixelMap: 

118 raise RuntimeError(f"Encountered unexpected class {className} associated with" 

119 " sphgeom pixelization YAML constructor") 

120 

121 return pixelMap[className](mapping["level"]) 

122 

123 

124# All the pixelization schemes use the same approach with getLevel 

125if yaml: 125 ↛ exitline 125 didn't exit the module, because the condition on line 125 was never false

126 for pixelSchemeCls in (HtmPixelization, Q3cPixelization, Mq3cPixelization, HealpixPixelization): 

127 yaml.add_representer(pixelSchemeCls, pixel_representer) 

128 for loader in YamlLoaders: 

129 yaml.add_constructor(f"lsst.sphgeom.{pixelSchemeCls.__name__}", pixel_constructor, Loader=loader)