diff --git a/sanic/config.py b/sanic/config.py
index 3fbc157f..7b7e170d 100644
--- a/sanic/config.py
+++ b/sanic/config.py
@@ -32,6 +32,7 @@ DEFAULT_CONFIG = {
"REAL_IP_HEADER": None,
"PROXIES_COUNT": None,
"FORWARDED_FOR_HEADER": "X-Forwarded-For",
+ "FALLBACK_ERROR_FORMAT": "html",
}
diff --git a/sanic/errorpages.py b/sanic/errorpages.py
index 2d17cbde..a4d6b494 100644
--- a/sanic/errorpages.py
+++ b/sanic/errorpages.py
@@ -1,13 +1,283 @@
import sys
+import typing as t
+from functools import partial
from traceback import extract_tb
-from sanic.exceptions import SanicException
+from sanic.exceptions import InvalidUsage, SanicException
from sanic.helpers import STATUS_CODES
-from sanic.response import html
+from sanic.request import Request
+from sanic.response import HTTPResponse, html, json, text
-# Here, There Be Dragons (custom HTML formatting to follow)
+try:
+ from ujson import dumps
+
+ dumps = partial(dumps, escape_forward_slashes=False)
+except ImportError: # noqa
+ from json import dumps # type: ignore
+
+
+FALLBACK_TEXT = (
+ "The server encountered an internal error and "
+ "cannot complete your request."
+)
+FALLBACK_STATUS = 500
+
+
+class BaseRenderer:
+ def __init__(self, request, exception, debug):
+ self.request = request
+ self.exception = exception
+ self.debug = debug
+
+ @property
+ def headers(self):
+ if isinstance(self.exception, SanicException):
+ return getattr(self.exception, "headers", {})
+ return {}
+
+ @property
+ def status(self):
+ if isinstance(self.exception, SanicException):
+ return getattr(self.exception, "status_code", FALLBACK_STATUS)
+ return FALLBACK_STATUS
+
+ @property
+ def text(self):
+ if self.debug or isinstance(self.exception, SanicException):
+ return str(self.exception)
+ return FALLBACK_TEXT
+
+ @property
+ def title(self):
+ status_text = STATUS_CODES.get(self.status, b"Error Occurred").decode()
+ return f"{self.status} — {status_text}"
+
+ def render(self):
+ output = (
+ self.full
+ if self.debug and not getattr(self.exception, "quiet", False)
+ else self.minimal
+ )
+ return output()
+
+ def minimal(self): # noqa
+ raise NotImplementedError
+
+ def full(self): # noqa
+ raise NotImplementedError
+
+
+class HTMLRenderer(BaseRenderer):
+ TRACEBACK_STYLE = """
+ html { font-family: sans-serif }
+ h2 { color: #888; }
+ .tb-wrapper p { margin: 0 }
+ .frame-border { margin: 1rem }
+ .frame-line > * { padding: 0.3rem 0.6rem }
+ .frame-line { margin-bottom: 0.3rem }
+ .frame-code { font-size: 16px; padding-left: 4ch }
+ .tb-wrapper { border: 1px solid #eee }
+ .tb-header { background: #eee; padding: 0.3rem; font-weight: bold }
+ .frame-descriptor { background: #e2eafb; font-size: 14px }
+ """
+ TRACEBACK_WRAPPER_HTML = (
+ ""
+ "{frame_html}
"
+ )
+ TRACEBACK_BORDER = (
+ ""
+ "The above exception was the direct cause of the following exception:"
+ "
"
+ )
+ TRACEBACK_LINE_HTML = (
+ ""
+ "
"
+ "File {0.filename}, line {0.lineno}, "
+ "in {0.name}"
+ "
{0.line}"
+ "
{title}
{text}\n"
+ "{body}"
+ )
+
+ def full(self):
+ return html(
+ self.OUTPUT_HTML.format(
+ title=self.title,
+ text=self.text,
+ style=self.TRACEBACK_STYLE,
+ body=self._generate_body(),
+ ),
+ status=self.status,
+ )
+
+ def minimal(self):
+ return html(
+ self.OUTPUT_HTML.format(
+ title=self.title,
+ text=self.text,
+ style=self.TRACEBACK_STYLE,
+ body="",
+ ),
+ status=self.status,
+ headers=self.headers,
+ )
+
+ @property
+ def text(self):
+ return escape(super().text)
+
+ @property
+ def title(self):
+ return escape(f"⚠️ {super().title}")
+
+ def _generate_body(self):
+ _, exc_value, __ = sys.exc_info()
+ exceptions = []
+ while exc_value:
+ exceptions.append(self._format_exc(exc_value))
+ exc_value = exc_value.__cause__
+
+ traceback_html = self.TRACEBACK_BORDER.join(reversed(exceptions))
+ appname = escape(self.request.app.name)
+ name = escape(self.exception.__class__.__name__)
+ value = escape(self.exception)
+ path = escape(self.request.path)
+ lines = [
+ f"
Traceback of {appname} (most recent call last):
",
+ f"{traceback_html}",
+ "",
+ f"{name}: {value} while handling path {path}",
+ "
⚠️ {title}
{text}\n"
- f"{_render_traceback_html(request, exception)}",
- status=status,
- )
-
- # Keeping it minimal with trailing newline for pretty curl/console output
- return html(
- f"
{title}"
- "\n"
- f"⚠️ {title}
{text}\n",
- status=status,
- headers=headers,
- )
+RENDERERS_BY_CONTENT_TYPE = {
+ "multipart/form-data": HTMLRenderer,
+ "application/json": JSONRenderer,
+ "text/plain": TextRenderer,
+}
-def _render_exception(exception):
- frames = extract_tb(exception.__traceback__)
- frame_html = "".join(TRACEBACK_LINE_HTML.format(frame) for frame in frames)
- return TRACEBACK_WRAPPER_HTML.format(
- exc_name=escape(exception.__class__.__name__),
- exc_value=escape(exception),
- frame_html=frame_html,
- )
+def exception_response(
+ request: Request,
+ exception: Exception,
+ debug: bool,
+ renderer: t.Type[t.Optional[BaseRenderer]] = None,
+) -> HTTPResponse:
+ """Render a response for the default FALLBACK exception handler"""
+ if not renderer:
+ renderer = HTMLRenderer
-def _render_traceback_html(request, exception):
- exc_type, exc_value, tb = sys.exc_info()
- exceptions = []
- while exc_value:
- exceptions.append(_render_exception(exc_value))
- exc_value = exc_value.__cause__
+ if request:
+ if request.app.config.FALLBACK_ERROR_FORMAT == "auto":
+ try:
+ renderer = JSONRenderer if request.json else HTMLRenderer
+ except InvalidUsage:
+ renderer = HTMLRenderer
- traceback_html = TRACEBACK_BORDER.join(reversed(exceptions))
- appname = escape(request.app.name)
- name = escape(exception.__class__.__name__)
- value = escape(exception)
- path = escape(request.path)
- return (
- f"
Traceback of {appname} (most recent call last):
"
- f"{traceback_html}"
- ""
- f"{name}: {value} while handling path {path}"
- )
+ content_type, *_ = request.headers.get(
+ "content-type", ""
+ ).split(";")
+ renderer = RENDERERS_BY_CONTENT_TYPE.get(
+ content_type, renderer
+ )
+ else:
+ render_format = request.app.config.FALLBACK_ERROR_FORMAT
+ renderer = RENDERERS_BY_CONFIG.get(render_format, renderer)
-
-TRACEBACK_STYLE = """
- html { font-family: sans-serif }
- h2 { color: #888; }
- .tb-wrapper p { margin: 0 }
- .frame-border { margin: 1rem }
- .frame-line > * { padding: 0.3rem 0.6rem }
- .frame-line { margin-bottom: 0.3rem }
- .frame-code { font-size: 16px; padding-left: 4ch }
- .tb-wrapper { border: 1px solid #eee }
- .tb-header { background: #eee; padding: 0.3rem; font-weight: bold }
- .frame-descriptor { background: #e2eafb; font-size: 14px }
-"""
-
-TRACEBACK_WRAPPER_HTML = (
- "
"
- "
{frame_html}
"
-)
-
-TRACEBACK_BORDER = (
- "
"
- "The above exception was the direct cause of the following exception:"
- "
"
-)
-
-TRACEBACK_LINE_HTML = (
- "
"
- "
"
- "File {0.filename}, line {0.lineno}, "
- "in {0.name}"
- "
{0.line}"
- "
"
-)
+ renderer = t.cast(t.Type[BaseRenderer], renderer)
+ return renderer(request, exception, debug).render()
diff --git a/tests/test_app.py b/tests/test_app.py
index dab46061..c9c44c39 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -126,7 +126,7 @@ def test_app_handle_request_handler_is_none(app, monkeypatch):
def handler(request):
return text("test")
- request, response = app.test_client.get("/test")
+ _, response = app.test_client.get("/test")
assert (
"'None' was returned while requesting a handler from the router"
diff --git a/tests/test_errorpages.py b/tests/test_errorpages.py
new file mode 100644
index 00000000..495c764f
--- /dev/null
+++ b/tests/test_errorpages.py
@@ -0,0 +1,86 @@
+import pytest
+
+from sanic import Sanic
+from sanic.errorpages import exception_response
+from sanic.exceptions import NotFound
+from sanic.request import Request
+from sanic.response import HTTPResponse
+
+
+@pytest.fixture
+def app():
+ app = Sanic("error_page_testing")
+
+ @app.route("/error", methods=["GET", "POST"])
+ def err(request):
+ raise Exception("something went wrong")
+
+ return app
+
+
+@pytest.fixture
+def fake_request(app):
+ return Request(b"/foobar", {}, "1.1", "GET", None, app)
+
+
+@pytest.mark.parametrize(
+ "fallback,content_type, exception, status",
+ (
+ (None, "text/html; charset=utf-8", Exception, 500),
+ ("html", "text/html; charset=utf-8", Exception, 500),
+ ("auto", "text/html; charset=utf-8", Exception, 500),
+ ("text", "text/plain; charset=utf-8", Exception, 500),
+ ("json", "application/json", Exception, 500),
+ (None, "text/html; charset=utf-8", NotFound, 404),
+ ("html", "text/html; charset=utf-8", NotFound, 404),
+ ("auto", "text/html; charset=utf-8", NotFound, 404),
+ ("text", "text/plain; charset=utf-8", NotFound, 404),
+ ("json", "application/json", NotFound, 404),
+ ),
+)
+def test_should_return_html_valid_setting(
+ fake_request, fallback, content_type, exception, status
+):
+ if fallback:
+ fake_request.app.config.FALLBACK_ERROR_FORMAT = fallback
+
+ try:
+ raise exception("bad stuff")
+ except Exception as e:
+ response = exception_response(fake_request, e, True)
+
+ assert isinstance(response, HTTPResponse)
+ assert response.status == status
+ assert response.content_type == content_type
+
+
+def test_auto_fallback_with_data(app):
+ app.config.FALLBACK_ERROR_FORMAT = "auto"
+
+ _, response = app.test_client.get("/error")
+ assert response.status == 500
+ assert response.content_type == "text/html; charset=utf-8"
+
+ _, response = app.test_client.post("/error", json={"foo": "bar"})
+ assert response.status == 500
+ assert response.content_type == "application/json"
+
+ _, response = app.test_client.post("/error", data={"foo": "bar"})
+ assert response.status == 500
+ assert response.content_type == "text/html; charset=utf-8"
+
+
+def test_auto_fallback_with_content_type(app):
+ app.config.FALLBACK_ERROR_FORMAT = "auto"
+
+ _, response = app.test_client.get(
+ "/error", headers={"content-type": "application/json"}
+ )
+ assert response.status == 500
+ assert response.content_type == "application/json"
+
+ _, response = app.test_client.get(
+ "/error", headers={"content-type": "text/plain"}
+ )
+ assert response.status == 500
+ assert response.content_type == "text/plain; charset=utf-8"