##// END OF EJS Templates
Remove deprecated encodestring infavor of encodebytes
Matthias Bussonnier -
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@@ -1,195 +1,199
1 # -*- coding: utf-8 -*-
1 # -*- coding: utf-8 -*-
2 """Tools for handling LaTeX."""
2 """Tools for handling LaTeX."""
3
3
4 # Copyright (c) IPython Development Team.
4 # Copyright (c) IPython Development Team.
5 # Distributed under the terms of the Modified BSD License.
5 # Distributed under the terms of the Modified BSD License.
6
6
7 from io import BytesIO, open
7 from io import BytesIO, open
8 from base64 import encodestring
9 import os
8 import os
10 import tempfile
9 import tempfile
11 import shutil
10 import shutil
12 import subprocess
11 import subprocess
13
12
14 from IPython.utils.process import find_cmd, FindCmdError
13 from IPython.utils.process import find_cmd, FindCmdError
15 from traitlets.config import get_config
14 from traitlets.config import get_config
16 from traitlets.config.configurable import SingletonConfigurable
15 from traitlets.config.configurable import SingletonConfigurable
17 from traitlets import List, Bool, Unicode
16 from traitlets import List, Bool, Unicode
18 from IPython.utils.py3compat import cast_unicode, cast_unicode_py2 as u
17 from IPython.utils.py3compat import cast_unicode, cast_unicode_py2 as u, PY3
18
19 if PY3:
20 from base64 import encodebytes
21 else :
22 from base64 import encodestring as encodebytes
19
23
20
24
21 class LaTeXTool(SingletonConfigurable):
25 class LaTeXTool(SingletonConfigurable):
22 """An object to store configuration of the LaTeX tool."""
26 """An object to store configuration of the LaTeX tool."""
23 def _config_default(self):
27 def _config_default(self):
24 return get_config()
28 return get_config()
25
29
26 backends = List(
30 backends = List(
27 Unicode(), ["matplotlib", "dvipng"],
31 Unicode(), ["matplotlib", "dvipng"],
28 help="Preferred backend to draw LaTeX math equations. "
32 help="Preferred backend to draw LaTeX math equations. "
29 "Backends in the list are checked one by one and the first "
33 "Backends in the list are checked one by one and the first "
30 "usable one is used. Note that `matplotlib` backend "
34 "usable one is used. Note that `matplotlib` backend "
31 "is usable only for inline style equations. To draw "
35 "is usable only for inline style equations. To draw "
32 "display style equations, `dvipng` backend must be specified. ",
36 "display style equations, `dvipng` backend must be specified. ",
33 # It is a List instead of Enum, to make configuration more
37 # It is a List instead of Enum, to make configuration more
34 # flexible. For example, to use matplotlib mainly but dvipng
38 # flexible. For example, to use matplotlib mainly but dvipng
35 # for display style, the default ["matplotlib", "dvipng"] can
39 # for display style, the default ["matplotlib", "dvipng"] can
36 # be used. To NOT use dvipng so that other repr such as
40 # be used. To NOT use dvipng so that other repr such as
37 # unicode pretty printing is used, you can use ["matplotlib"].
41 # unicode pretty printing is used, you can use ["matplotlib"].
38 config=True)
42 config=True)
39
43
40 use_breqn = Bool(
44 use_breqn = Bool(
41 True,
45 True,
42 help="Use breqn.sty to automatically break long equations. "
46 help="Use breqn.sty to automatically break long equations. "
43 "This configuration takes effect only for dvipng backend.",
47 "This configuration takes effect only for dvipng backend.",
44 config=True)
48 config=True)
45
49
46 packages = List(
50 packages = List(
47 ['amsmath', 'amsthm', 'amssymb', 'bm'],
51 ['amsmath', 'amsthm', 'amssymb', 'bm'],
48 help="A list of packages to use for dvipng backend. "
52 help="A list of packages to use for dvipng backend. "
49 "'breqn' will be automatically appended when use_breqn=True.",
53 "'breqn' will be automatically appended when use_breqn=True.",
50 config=True)
54 config=True)
51
55
52 preamble = Unicode(
56 preamble = Unicode(
53 help="Additional preamble to use when generating LaTeX source "
57 help="Additional preamble to use when generating LaTeX source "
54 "for dvipng backend.",
58 "for dvipng backend.",
55 config=True)
59 config=True)
56
60
57
61
58 def latex_to_png(s, encode=False, backend=None, wrap=False):
62 def latex_to_png(s, encode=False, backend=None, wrap=False):
59 """Render a LaTeX string to PNG.
63 """Render a LaTeX string to PNG.
60
64
61 Parameters
65 Parameters
62 ----------
66 ----------
63 s : text
67 s : text
64 The raw string containing valid inline LaTeX.
68 The raw string containing valid inline LaTeX.
65 encode : bool, optional
69 encode : bool, optional
66 Should the PNG data base64 encoded to make it JSON'able.
70 Should the PNG data base64 encoded to make it JSON'able.
67 backend : {matplotlib, dvipng}
71 backend : {matplotlib, dvipng}
68 Backend for producing PNG data.
72 Backend for producing PNG data.
69 wrap : bool
73 wrap : bool
70 If true, Automatically wrap `s` as a LaTeX equation.
74 If true, Automatically wrap `s` as a LaTeX equation.
71
75
72 None is returned when the backend cannot be used.
76 None is returned when the backend cannot be used.
73
77
74 """
78 """
75 s = cast_unicode(s)
79 s = cast_unicode(s)
76 allowed_backends = LaTeXTool.instance().backends
80 allowed_backends = LaTeXTool.instance().backends
77 if backend is None:
81 if backend is None:
78 backend = allowed_backends[0]
82 backend = allowed_backends[0]
79 if backend not in allowed_backends:
83 if backend not in allowed_backends:
80 return None
84 return None
81 if backend == 'matplotlib':
85 if backend == 'matplotlib':
82 f = latex_to_png_mpl
86 f = latex_to_png_mpl
83 elif backend == 'dvipng':
87 elif backend == 'dvipng':
84 f = latex_to_png_dvipng
88 f = latex_to_png_dvipng
85 else:
89 else:
86 raise ValueError('No such backend {0}'.format(backend))
90 raise ValueError('No such backend {0}'.format(backend))
87 bin_data = f(s, wrap)
91 bin_data = f(s, wrap)
88 if encode and bin_data:
92 if encode and bin_data:
89 bin_data = encodestring(bin_data)
93 bin_data = encodebytes(bin_data)
90 return bin_data
94 return bin_data
91
95
92
96
93 def latex_to_png_mpl(s, wrap):
97 def latex_to_png_mpl(s, wrap):
94 try:
98 try:
95 from matplotlib import mathtext
99 from matplotlib import mathtext
96 except ImportError:
100 except ImportError:
97 return None
101 return None
98
102
99 # mpl mathtext doesn't support display math, force inline
103 # mpl mathtext doesn't support display math, force inline
100 s = s.replace('$$', '$')
104 s = s.replace('$$', '$')
101 if wrap:
105 if wrap:
102 s = u'${0}$'.format(s)
106 s = u'${0}$'.format(s)
103
107
104 mt = mathtext.MathTextParser('bitmap')
108 mt = mathtext.MathTextParser('bitmap')
105 f = BytesIO()
109 f = BytesIO()
106 mt.to_png(f, s, fontsize=12)
110 mt.to_png(f, s, fontsize=12)
107 return f.getvalue()
111 return f.getvalue()
108
112
109
113
110 def latex_to_png_dvipng(s, wrap):
114 def latex_to_png_dvipng(s, wrap):
111 try:
115 try:
112 find_cmd('latex')
116 find_cmd('latex')
113 find_cmd('dvipng')
117 find_cmd('dvipng')
114 except FindCmdError:
118 except FindCmdError:
115 return None
119 return None
116 try:
120 try:
117 workdir = tempfile.mkdtemp()
121 workdir = tempfile.mkdtemp()
118 tmpfile = os.path.join(workdir, "tmp.tex")
122 tmpfile = os.path.join(workdir, "tmp.tex")
119 dvifile = os.path.join(workdir, "tmp.dvi")
123 dvifile = os.path.join(workdir, "tmp.dvi")
120 outfile = os.path.join(workdir, "tmp.png")
124 outfile = os.path.join(workdir, "tmp.png")
121
125
122 with open(tmpfile, "w", encoding='utf8') as f:
126 with open(tmpfile, "w", encoding='utf8') as f:
123 f.writelines(genelatex(s, wrap))
127 f.writelines(genelatex(s, wrap))
124
128
125 with open(os.devnull, 'wb') as devnull:
129 with open(os.devnull, 'wb') as devnull:
126 subprocess.check_call(
130 subprocess.check_call(
127 ["latex", "-halt-on-error", "-interaction", "batchmode", tmpfile],
131 ["latex", "-halt-on-error", "-interaction", "batchmode", tmpfile],
128 cwd=workdir, stdout=devnull, stderr=devnull)
132 cwd=workdir, stdout=devnull, stderr=devnull)
129
133
130 subprocess.check_call(
134 subprocess.check_call(
131 ["dvipng", "-T", "tight", "-x", "1500", "-z", "9",
135 ["dvipng", "-T", "tight", "-x", "1500", "-z", "9",
132 "-bg", "transparent", "-o", outfile, dvifile], cwd=workdir,
136 "-bg", "transparent", "-o", outfile, dvifile], cwd=workdir,
133 stdout=devnull, stderr=devnull)
137 stdout=devnull, stderr=devnull)
134
138
135 with open(outfile, "rb") as f:
139 with open(outfile, "rb") as f:
136 return f.read()
140 return f.read()
137 finally:
141 finally:
138 shutil.rmtree(workdir)
142 shutil.rmtree(workdir)
139
143
140
144
141 def kpsewhich(filename):
145 def kpsewhich(filename):
142 """Invoke kpsewhich command with an argument `filename`."""
146 """Invoke kpsewhich command with an argument `filename`."""
143 try:
147 try:
144 find_cmd("kpsewhich")
148 find_cmd("kpsewhich")
145 proc = subprocess.Popen(
149 proc = subprocess.Popen(
146 ["kpsewhich", filename],
150 ["kpsewhich", filename],
147 stdout=subprocess.PIPE, stderr=subprocess.PIPE)
151 stdout=subprocess.PIPE, stderr=subprocess.PIPE)
148 (stdout, stderr) = proc.communicate()
152 (stdout, stderr) = proc.communicate()
149 return stdout.strip().decode('utf8', 'replace')
153 return stdout.strip().decode('utf8', 'replace')
150 except FindCmdError:
154 except FindCmdError:
151 pass
155 pass
152
156
153
157
154 def genelatex(body, wrap):
158 def genelatex(body, wrap):
155 """Generate LaTeX document for dvipng backend."""
159 """Generate LaTeX document for dvipng backend."""
156 lt = LaTeXTool.instance()
160 lt = LaTeXTool.instance()
157 breqn = wrap and lt.use_breqn and kpsewhich("breqn.sty")
161 breqn = wrap and lt.use_breqn and kpsewhich("breqn.sty")
158 yield u(r'\documentclass{article}')
162 yield u(r'\documentclass{article}')
159 packages = lt.packages
163 packages = lt.packages
160 if breqn:
164 if breqn:
161 packages = packages + ['breqn']
165 packages = packages + ['breqn']
162 for pack in packages:
166 for pack in packages:
163 yield u(r'\usepackage{{{0}}}'.format(pack))
167 yield u(r'\usepackage{{{0}}}'.format(pack))
164 yield u(r'\pagestyle{empty}')
168 yield u(r'\pagestyle{empty}')
165 if lt.preamble:
169 if lt.preamble:
166 yield lt.preamble
170 yield lt.preamble
167 yield u(r'\begin{document}')
171 yield u(r'\begin{document}')
168 if breqn:
172 if breqn:
169 yield u(r'\begin{dmath*}')
173 yield u(r'\begin{dmath*}')
170 yield body
174 yield body
171 yield u(r'\end{dmath*}')
175 yield u(r'\end{dmath*}')
172 elif wrap:
176 elif wrap:
173 yield u'$${0}$$'.format(body)
177 yield u'$${0}$$'.format(body)
174 else:
178 else:
175 yield body
179 yield body
176 yield u'\end{document}'
180 yield u'\end{document}'
177
181
178
182
179 _data_uri_template_png = u"""<img src="data:image/png;base64,%s" alt=%s />"""
183 _data_uri_template_png = u"""<img src="data:image/png;base64,%s" alt=%s />"""
180
184
181 def latex_to_html(s, alt='image'):
185 def latex_to_html(s, alt='image'):
182 """Render LaTeX to HTML with embedded PNG data using data URIs.
186 """Render LaTeX to HTML with embedded PNG data using data URIs.
183
187
184 Parameters
188 Parameters
185 ----------
189 ----------
186 s : str
190 s : str
187 The raw string containing valid inline LateX.
191 The raw string containing valid inline LateX.
188 alt : str
192 alt : str
189 The alt text to use for the HTML.
193 The alt text to use for the HTML.
190 """
194 """
191 base64_data = latex_to_png(s, encode=True).decode('ascii')
195 base64_data = latex_to_png(s, encode=True).decode('ascii')
192 if base64_data:
196 if base64_data:
193 return _data_uri_template_png % (base64_data, alt)
197 return _data_uri_template_png % (base64_data, alt)
194
198
195
199
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