from pathlib import Path import jinja2 from django.conf import settings from django.template import TemplateDoesNotExist, TemplateSyntaxError from django.utils.functional import cached_property from django.utils.module_loading import import_string from .base import BaseEngine from .utils import csrf_input_lazy, csrf_token_lazy class Jinja2(BaseEngine): app_dirname = "jinja2" def __init__(self, params): params = params.copy() options = params.pop("OPTIONS").copy() super().__init__(params) self.context_processors = options.pop("context_processors", []) environment = options.pop("environment", "jinja2.Environment") environment_cls = import_string(environment) if "loader" not in options: options["loader"] = jinja2.FileSystemLoader(self.template_dirs) options.setdefault("autoescape", True) options.setdefault("auto_reload", settings.DEBUG) options.setdefault( "undefined", jinja2.DebugUndefined if settings.DEBUG else jinja2.Undefined ) self.env = environment_cls(**options) def from_string(self, template_code): return Template(self.env.from_string(template_code), self) def get_template(self, template_name): try: return Template(self.env.get_template(template_name), self) except jinja2.TemplateNotFound as exc: raise TemplateDoesNotExist(exc.name, backend=self) from exc except jinja2.TemplateSyntaxError as exc: new = TemplateSyntaxError(exc.args) new.template_debug = get_exception_info(exc) raise new from exc @cached_property def template_context_processors(self): return [import_string(path) for path in self.context_processors] class Template: def __init__(self, template, backend): self.template = template self.backend = backend self.origin = Origin( name=template.filename, template_name=template.name, ) def render(self, context=None, request=None): if context is None: context = {} if request is not None: context["request"] = request context["csrf_input"] = csrf_input_lazy(request) context["csrf_token"] = csrf_token_lazy(request) for context_processor in self.backend.template_context_processors: context.update(context_processor(request)) try: return self.template.render(context) except jinja2.TemplateSyntaxError as exc: new = TemplateSyntaxError(exc.args) new.template_debug = get_exception_info(exc) raise new from exc class Origin: """ A container to hold debug information as described in the template API documentation. """ def __init__(self, name, template_name): self.name = name self.template_name = template_name def get_exception_info(exception): """ Format exception information for display on the debug page using the structure described in the template API documentation. """ context_lines = 10 lineno = exception.lineno source = exception.source if source is None: exception_file = Path(exception.filename) if exception_file.exists(): source = exception_file.read_text() if source is not None: lines = list(enumerate(source.strip().split("\n"), start=1)) during = lines[lineno - 1][1] total = len(lines) top = max(0, lineno - context_lines - 1) bottom = min(total, lineno + context_lines) else: during = "" lines = [] total = top = bottom = 0 return { "name": exception.filename, "message": exception.message, "source_lines": lines[top:bottom], "line": lineno, "before": "", "during": during, "after": "", "total": total, "top": top, "bottom": bottom, }