1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
import typing as t
from jinja2 import BaseLoader
from jinja2 import Environment as BaseEnvironment
from jinja2 import Template
from jinja2 import TemplateNotFound
from .globals import _cv_app
from .globals import _cv_request
from .globals import current_app
from .globals import request
from .helpers import stream_with_context
from .signals import before_render_template
from .signals import template_rendered
if t.TYPE_CHECKING: # pragma: no cover
from .app import Flask
from .scaffold import Scaffold
def _default_template_ctx_processor() -> t.Dict[str, t.Any]:
"""Default template context processor. Injects `request`,
`session` and `g`.
"""
appctx = _cv_app.get(None)
reqctx = _cv_request.get(None)
rv: t.Dict[str, t.Any] = {}
if appctx is not None:
rv["g"] = appctx.g
if reqctx is not None:
rv["request"] = reqctx.request
rv["session"] = reqctx.session
return rv
class Environment(BaseEnvironment):
"""Works like a regular Jinja2 environment but has some additional
knowledge of how Flask's blueprint works so that it can prepend the
name of the blueprint to referenced templates if necessary.
"""
def __init__(self, app: "Flask", **options: t.Any) -> None:
if "loader" not in options:
options["loader"] = app.create_global_jinja_loader()
BaseEnvironment.__init__(self, **options)
self.app = app
class DispatchingJinjaLoader(BaseLoader):
"""A loader that looks for templates in the application and all
the blueprint folders.
"""
def __init__(self, app: "Flask") -> None:
self.app = app
def get_source( # type: ignore
self, environment: Environment, template: str
) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable]]:
if self.app.config["EXPLAIN_TEMPLATE_LOADING"]:
return self._get_source_explained(environment, template)
return self._get_source_fast(environment, template)
def _get_source_explained(
self, environment: Environment, template: str
) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable]]:
attempts = []
rv: t.Optional[t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]]
trv: t.Optional[
t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]
] = None
for srcobj, loader in self._iter_loaders(template):
try:
rv = loader.get_source(environment, template)
if trv is None:
trv = rv
except TemplateNotFound:
rv = None
attempts.append((loader, srcobj, rv))
from .debughelpers import explain_template_loading_attempts
explain_template_loading_attempts(self.app, template, attempts)
if trv is not None:
return trv
raise TemplateNotFound(template)
def _get_source_fast(
self, environment: Environment, template: str
) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable]]:
for _srcobj, loader in self._iter_loaders(template):
try:
return loader.get_source(environment, template)
except TemplateNotFound:
continue
raise TemplateNotFound(template)
def _iter_loaders(
self, template: str
) -> t.Generator[t.Tuple["Scaffold", BaseLoader], None, None]:
loader = self.app.jinja_loader
if loader is not None:
yield self.app, loader
for blueprint in self.app.iter_blueprints():
loader = blueprint.jinja_loader
if loader is not None:
yield blueprint, loader
def list_templates(self) -> t.List[str]:
result = set()
loader = self.app.jinja_loader
if loader is not None:
result.update(loader.list_templates())
for blueprint in self.app.iter_blueprints():
loader = blueprint.jinja_loader
if loader is not None:
for template in loader.list_templates():
result.add(template)
return list(result)
def _render(app: "Flask", template: Template, context: t.Dict[str, t.Any]) -> str:
app.update_template_context(context)
before_render_template.send(app, template=template, context=context)
rv = template.render(context)
template_rendered.send(app, template=template, context=context)
return rv
def render_template(
template_name_or_list: t.Union[str, Template, t.List[t.Union[str, Template]]],
**context: t.Any
) -> str:
"""Render a template by name with the given context.
:param template_name_or_list: The name of the template to render. If
a list is given, the first name to exist will be rendered.
:param context: The variables to make available in the template.
"""
app = current_app._get_current_object() # type: ignore[attr-defined]
template = app.jinja_env.get_or_select_template(template_name_or_list)
return _render(app, template, context)
def render_template_string(source: str, **context: t.Any) -> str:
"""Render a template from the given source string with the given
context.
:param source: The source code of the template to render.
:param context: The variables to make available in the template.
"""
app = current_app._get_current_object() # type: ignore[attr-defined]
template = app.jinja_env.from_string(source)
return _render(app, template, context)
def _stream(
app: "Flask", template: Template, context: t.Dict[str, t.Any]
) -> t.Iterator[str]:
app.update_template_context(context)
before_render_template.send(app, template=template, context=context)
def generate() -> t.Iterator[str]:
yield from template.generate(context)
template_rendered.send(app, template=template, context=context)
rv = generate()
# If a request context is active, keep it while generating.
if request:
rv = stream_with_context(rv)
return rv
def stream_template(
template_name_or_list: t.Union[str, Template, t.List[t.Union[str, Template]]],
**context: t.Any
) -> t.Iterator[str]:
"""Render a template by name with the given context as a stream.
This returns an iterator of strings, which can be used as a
streaming response from a view.
:param template_name_or_list: The name of the template to render. If
a list is given, the first name to exist will be rendered.
:param context: The variables to make available in the template.
.. versionadded:: 2.2
"""
app = current_app._get_current_object() # type: ignore[attr-defined]
template = app.jinja_env.get_or_select_template(template_name_or_list)
return _stream(app, template, context)
def stream_template_string(source: str, **context: t.Any) -> t.Iterator[str]:
"""Render a template from the given source string with the given
context as a stream. This returns an iterator of strings, which can
be used as a streaming response from a view.
:param source: The source code of the template to render.
:param context: The variables to make available in the template.
.. versionadded:: 2.2
"""
app = current_app._get_current_object() # type: ignore[attr-defined]
template = app.jinja_env.from_string(source)
return _stream(app, template, context)
|
