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

41 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 HtmPixelization, 

40 Mq3cPixelization, 

41 Region, 

42 Q3cPixelization, 

43) 

44 

45 

46if yaml: 46 ↛ 60line 46 didn't jump to line 60, because the condition on line 46 was never false

47 try: 

48 # CLoader is not always available 

49 from yaml import CLoader 

50 except ImportError: 

51 CLoader = None 

52 

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

54 if CLoader is not None: 54 ↛ 60line 54 didn't jump to line 60, because the condition on line 54 was never false

55 YamlLoaders += (CLoader,) 

56 

57 

58# Regions 

59 

60def region_representer(dumper, data): 

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

62 

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

64 storing the hex encoded byte string. 

65 """ 

66 encoded = data.encode() 

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

68 {"encoded": encoded.hex()}) 

69 

70 

71def region_constructor(loader, node): 

72 """Construct a sphgeom region from YAML""" 

73 mapping = loader.construct_mapping(node) 

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

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

76 # correct type. 

77 return Region.decode(encoded) 

78 

79 

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

81if yaml: 81 ↛ 91line 81 didn't jump to line 91, because the condition on line 81 was never false

82 for region_class in (ConvexPolygon, Ellipse, Circle, Box): 

83 yaml.add_representer(region_class, region_representer) 

84 

85 for loader in YamlLoaders: 

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

87 

88 

89# Pixelization schemes 

90 

91def pixel_representer(dumper, data): 

92 """Represent a pixelization in YAML 

93 

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

95 ``level``. 

96 """ 

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

98 {"level": data.getLevel()}) 

99 

100 

101def pixel_constructor(loader, node): 

102 """Construct a pixelization object from YAML. 

103 """ 

104 mapping = loader.construct_mapping(node) 

105 

106 className = node.tag 

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

108 "lsst.sphgeom.Mq3cPixelization": Mq3cPixelization, 

109 "lsst.sphgeom.HtmPixelization": HtmPixelization, 

110 } 

111 

112 if className not in pixelMap: 

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

114 " sphgeom pixelization YAML constructor") 

115 

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

117 

118 

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

120if yaml: 120 ↛ exitline 120 didn't exit the module, because the condition on line 120 was never false

121 for pixelSchemeCls in (HtmPixelization, Q3cPixelization, Mq3cPixelization): 

122 yaml.add_representer(pixelSchemeCls, pixel_representer) 

123 for loader in YamlLoaders: 

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