Nicer traceback formatting (#2667)

Co-authored-by: L. Kärkkäinen <98187+Tronic@users.noreply.github.com>
Co-authored-by: Adam Hopkins <adam@amhopkins.com>
Co-authored-by: L. Karkkainen <tronic@users.noreply.github.com>
Co-authored-by: SML <smlbiobot@gmail.com>

pyproject.toml

@@ -24,5 +24,6 @@ module = [
     "sanic_routing.*",
     "aioquic.*",
     "html5tagger.*",
+    "tracerite.*",
 ]
 ignore_missing_imports = true

sanic/app.py

@@ -875,6 +875,8 @@ class Sanic(StaticHandleMixin, BaseSanic, StartupMixin, metaclass=TouchUpMeta):
         :param request: HTTP Request object
         :return: Nothing
         """
+        __tracebackhide__ = True
+
         await self.dispatch(
             "http.lifecycle.handle",
             inline=True,

sanic/application/logo.py

@@ -40,7 +40,7 @@ FULL_COLOR_LOGO = """
 
 """  # noqa
 
-SVG_LOGO = """<svg id=logo alt=Sanic viewBox="0 0 964 279"><path d="M107 222c9-2 10-20 1-22s-20-2-30-2-17 7-16 14 6 10 15 10h30zm115-1c16-2 30-11 35-23s6-24 2-33-6-14-15-20-24-11-38-10c-7 3-10 13-5 19s17-1 24 4 15 14 13 24-5 15-14 18-50 0-74 0h-17c-6 4-10 15-4 20s16 2 23 3zM251 83q9-1 9-7 0-15-10-16h-13c-10 6-10 20 0 22zM147 60c-4 0-10 3-11 11s5 13 10 12 42 0 67 0c5-3 7-10 6-15s-4-8-9-8zm-33 1c-8 0-16 0-24 3s-20 10-25 20-6 24-4 36 15 22 26 27 78 8 94 3c4-4 4-12 0-18s-69 8-93-10c-8-7-9-23 0-30s12-10 20-10 12 2 16-3 1-15-5-18z" fill="#ff0d68"/><path d="M676 74c0-14-18-9-20 0s0 30 0 39 20 9 20 2zm-297-10c-12 2-15 12-23 23l-41 58H340l22-30c8-12 23-13 30-4s20 24 24 38-10 10-17 10l-68 2q-17 1-48 30c-7 6-10 20 0 24s15-8 20-13 20 -20 58-21h50 c20 2 33 9 52 30 8 10 24-4 16-13L384 65q-3-2-5-1zm131 0c-10 1-12 12-11 20v96c1 10-3 23 5 32s20-5 17-15c0-23-3-46 2-67 5-12 22-14 32-5l103 87c7 5 19 1 18-9v-64c-3-10-20-9-21 2s-20 22-30 13l-97-80c-5-4-10-10-18-10zM701 76v128c2 10 15 12 20 4s0-102 0-124s-20-18-20-7z    M850 63c-35 0-69-2-86 15s-20 60-13 66 13 8 16 0 1-10 1-27 12-26 20-32 66-5 85-5 31 4 31-10-18-7-54-7M764 159c-6-2-15-2-16 12s19 37 33 43 23 8 25-4-4-11-11-14q-9-3-22-18c-4-7-3-16-10-19zM828 196c-4 0-8 1-10 5s-4 12 0 15 8 2 12 2h60c5 0 10-2 12-6 3-7-1-16-8-16z" fill="#e1e1e1"/></svg>"""  # noqa
+SVG_LOGO_SIMPLE = """<svg id=logo-simple viewBox="0 0 964 279"><desc>Sanic</desc><path d="M107 222c9-2 10-20 1-22s-20-2-30-2-17 7-16 14 6 10 15 10h30zm115-1c16-2 30-11 35-23s6-24 2-33-6-14-15-20-24-11-38-10c-7 3-10 13-5 19s17-1 24 4 15 14 13 24-5 15-14 18-50 0-74 0h-17c-6 4-10 15-4 20s16 2 23 3zM251 83q9-1 9-7 0-15-10-16h-13c-10 6-10 20 0 22zM147 60c-4 0-10 3-11 11s5 13 10 12 42 0 67 0c5-3 7-10 6-15s-4-8-9-8zm-33 1c-8 0-16 0-24 3s-20 10-25 20-6 24-4 36 15 22 26 27 78 8 94 3c4-4 4-12 0-18s-69 8-93-10c-8-7-9-23 0-30s12-10 20-10 12 2 16-3 1-15-5-18z" fill="#ff0d68"/><path d="M676 74c0-14-18-9-20 0s0 30 0 39 20 9 20 2zm-297-10c-12 2-15 12-23 23l-41 58H340l22-30c8-12 23-13 30-4s20 24 24 38-10 10-17 10l-68 2q-17 1-48 30c-7 6-10 20 0 24s15-8 20-13 20 -20 58-21h50 c20 2 33 9 52 30 8 10 24-4 16-13L384 65q-3-2-5-1zm131 0c-10 1-12 12-11 20v96c1 10-3 23 5 32s20-5 17-15c0-23-3-46 2-67 5-12 22-14 32-5l103 87c7 5 19 1 18-9v-64c-3-10-20-9-21 2s-20 22-30 13l-97-80c-5-4-10-10-18-10zM701 76v128c2 10 15 12 20 4s0-102 0-124s-20-18-20-7z M850 63c-35 0-69-2-86 15s-20 60-13 66 13 8 16 0 1-10 1-27 12-26 20-32 66-5 85-5 31 4 31-10-18-7-54-7M764 159c-6-2-15-2-16 12s19 37 33 43 23 8 25-4-4-11-11-14q-9-3-22-18c-4-7-3-16-10-19zM828 196c-4 0-8 1-10 5s-4 12 0 15 8 2 12 2h60c5 0 10-2 12-6 3-7-1-16-8-16z" fill="#1f1f1f"/></svg>"""  # noqa
 
 ansi_pattern = re.compile(r"\x1B(?:[@-Z\\-_]|\[[0-?]*[ -/]*[@-~])")
 

sanic/errorpages.py

@@ -23,6 +23,7 @@ from traceback import extract_tb
 from sanic.exceptions import BadRequest, SanicException
 from sanic.helpers import STATUS_CODES
 from sanic.log import deprecation, logger
+from sanic.pages.error import ErrorPage
 from sanic.response import html, json, text
 
 
@@ -38,10 +39,9 @@ if t.TYPE_CHECKING:
     from sanic import HTTPResponse, Request
 
 DEFAULT_FORMAT = "auto"
-FALLBACK_TEXT = (
+FALLBACK_TEXT = """\
-    "The server encountered an internal error and "
+The application encountered an unexpected error and could not continue.\
-    "cannot complete your request."
+"""
-)
 FALLBACK_STATUS = 500
 JSON = "application/json"
 
@@ -117,134 +117,18 @@ class HTMLRenderer(BaseRenderer):
     The default fallback type.
     """
 
-    TRACEBACK_STYLE = """
-        html { font-family: sans-serif }
-        h2 { color: #888; }
-        .tb-wrapper p, dl, dd { margin: 0 }
-        .frame-border { margin: 1rem }
-        .frame-line > *, dt, dd { padding: 0.3rem 0.6rem }
-        .frame-line, dl { margin-bottom: 0.3rem }
-        .frame-code, dd { font-size: 16px; padding-left: 4ch }
-        .tb-wrapper, dl { border: 1px solid #eee }
-        .tb-header,.obj-header {
-            background: #eee; padding: 0.3rem; font-weight: bold
-        }
-        .frame-descriptor, dt { background: #e2eafb; font-size: 14px }
-    """
-    TRACEBACK_WRAPPER_HTML = (
-        "<div class=tb-header>{exc_name}: {exc_value}</div>"
-        "<div class=tb-wrapper>{frame_html}</div>"
-    )
-    TRACEBACK_BORDER = (
-        "<div class=frame-border>"
-        "The above exception was the direct cause of the following exception:"
-        "</div>"
-    )
-    TRACEBACK_LINE_HTML = (
-        "<div class=frame-line>"
-        "<p class=frame-descriptor>"
-        "File {0.filename}, line <i>{0.lineno}</i>, "
-        "in <code><b>{0.name}</b></code>"
-        "<p class=frame-code><code>{0.line}</code>"
-        "</div>"
-    )
-    OBJECT_WRAPPER_HTML = (
-        "<div class=obj-header>{title}</div>"
-        "<dl class={obj_type}>{display_html}</dl>"
-    )
-    OBJECT_DISPLAY_HTML = "<dt>{key}</dt><dd><code>{value}</code></dd>"
-    OUTPUT_HTML = (
-        "<!DOCTYPE html><html lang=en>"
-        "<meta charset=UTF-8><title>{title}</title>\n"
-        "<style>{style}</style>\n"
-        "<h1>{title}</h1><p>{text}\n"
-        "{body}"
-    )
-
     def full(self) -> HTTPResponse:
-        return html(
+        page = ErrorPage(
-            self.OUTPUT_HTML.format(
+            debug=self.debug,
-                title=self.title,
+            title=super().title,
-                text=self.text,
+            text=super().text,
-                style=self.TRACEBACK_STYLE,
+            request=self.request,
-                body=self._generate_body(full=True),
+            exc=self.exception,
-            ),
-            status=self.status,
         )
+        return html(page.render(), status=self.status, headers=self.headers)
 
     def minimal(self) -> HTTPResponse:
-        return html(
+        return self.full()
-            self.OUTPUT_HTML.format(
-                title=self.title,
-                text=self.text,
-                style=self.TRACEBACK_STYLE,
-                body=self._generate_body(full=False),
-            ),
-            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, *, full):
-        lines = []
-        if full:
-            _, 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"<h2>Traceback of {appname} " "(most recent call last):</h2>",
-                f"{traceback_html}",
-                "<div class=summary><p>",
-                f"<b>{name}: {value}</b> "
-                f"while handling path <code>{path}</code>",
-                "</div>",
-            ]
-
-        for attr, display in (("context", True), ("extra", bool(full))):
-            info = getattr(self.exception, attr, None)
-            if info and display:
-                lines.append(self._generate_object_display(info, attr))
-
-        return "\n".join(lines)
-
-    def _generate_object_display(
-        self, obj: t.Dict[str, t.Any], descriptor: str
-    ) -> str:
-        display = "".join(
-            self.OBJECT_DISPLAY_HTML.format(key=key, value=value)
-            for key, value in obj.items()
-        )
-        return self.OBJECT_WRAPPER_HTML.format(
-            title=descriptor.title(),
-            display_html=display,
-            obj_type=descriptor.lower(),
-        )
-
-    def _format_exc(self, exc):
-        frames = extract_tb(exc.__traceback__)
-        frame_html = "".join(
-            self.TRACEBACK_LINE_HTML.format(frame) for frame in frames
-        )
-        return self.TRACEBACK_WRAPPER_HTML.format(
-            exc_name=escape(exc.__class__.__name__),
-            exc_value=escape(exc),
-            frame_html=frame_html,
-        )
 
 
 class TextRenderer(BaseRenderer):

sanic/pages/base.py

@@ -1,18 +1,19 @@
 from abc import ABC, abstractmethod
 
-from html5tagger import HTML, Document
+from html5tagger import HTML, Builder, Document
 
 from sanic import __version__ as VERSION
-from sanic.application.logo import SVG_LOGO
+from sanic.application.logo import SVG_LOGO_SIMPLE
 from sanic.pages.css import CSS
 
 
 class BasePage(ABC, metaclass=CSS):  # no cov
-    TITLE = "Unknown"
+    TITLE = "Sanic"
+    HEADING = None
     CSS: str
+    doc: Builder
 
     def __init__(self, debug: bool = True) -> None:
-        self.doc = Document(self.TITLE, lang="en")
         self.debug = debug
 
     @property
@@ -20,6 +21,7 @@ class BasePage(ABC, metaclass=CSS):  # no cov
         return self.CSS
 
     def render(self) -> str:
+        self.doc = Document(self.TITLE, lang="en", id="sanic")
         self._head()
         self._body()
         self._foot()
@@ -28,7 +30,7 @@ class BasePage(ABC, metaclass=CSS):  # no cov
     def _head(self) -> None:
         self.doc.style(HTML(self.style))
         with self.doc.header:
-            self.doc.div(self.TITLE)
+            self.doc.div(self.HEADING or self.TITLE)
 
     def _foot(self) -> None:
         with self.doc.footer:
@@ -37,6 +39,23 @@ class BasePage(ABC, metaclass=CSS):  # no cov
                 self._sanic_logo()
             if self.debug:
                 self.doc.div(f"Version {VERSION}")
+                with self.doc.div:
+                    for idx, (title, href) in enumerate(
+                        (
+                            ("Docs", "https://sanic.dev"),
+                            ("Help", "https://sanic.dev/en/help.html"),
+                            ("GitHub", "https://github.com/sanic-org/sanic"),
+                        )
+                    ):
+                        if idx > 0:
+                            self.doc(" | ")
+                        self.doc.a(
+                            title,
+                            href=href,
+                            target="_blank",
+                            referrerpolicy="no-referrer",
+                        )
+                self.doc.div("DEBUG mode")
 
     @abstractmethod
     def _body(self) -> None:
@@ -44,7 +63,7 @@ class BasePage(ABC, metaclass=CSS):  # no cov
 
     def _sanic_logo(self) -> None:
         self.doc.a(
-            HTML(SVG_LOGO),
+            HTML(SVG_LOGO_SIMPLE),
             href="https://sanic.dev",
             target="_blank",
             referrerpolicy="no-referrer",

sanic/pages/css.py

@@ -24,8 +24,8 @@ class CSS(ABCMeta):
     def __new__(cls, name, bases, attrs):
         Page = super().__new__(cls, name, bases, attrs)
         # Use a locally defined STYLE or the one from styles directory
-        s = _extract_style(attrs.get("STYLE"), name)
+        Page.STYLE = _extract_style(attrs.get("STYLE_FILE"), name)
-        Page.STYLE = f"\n/* {name} */\n{s.strip()}\n" if s else ""
+        Page.STYLE += attrs.get("STYLE_APPEND", "")
         # Combine with all ancestor styles
         Page.CSS = "".join(
             Class.STYLE

sanic/pages/error.py

@@ -0,0 +1,109 @@
+from typing import Any, Mapping
+
+import tracerite.html
+
+from html5tagger import E
+from tracerite import html_traceback, inspector
+
+from sanic.request import Request
+
+from .base import BasePage
+
+
+# Avoid showing the request in the traceback variable inspectors
+inspector.blacklist_types += (Request,)
+
+ENDUSER_TEXT = """\
+We're sorry, but it looks like something went wrong. Please try refreshing \
+the page or navigating back to the homepage. If the issue persists, our \
+technical team is working to resolve it as soon as possible. We apologize \
+for the inconvenience and appreciate your patience.\
+"""
+
+
+class ErrorPage(BasePage):
+    STYLE_APPEND = tracerite.html.style
+
+    def __init__(
+        self,
+        debug: bool,
+        title: str,
+        text: str,
+        request: Request,
+        exc: Exception,
+    ) -> None:
+        super().__init__(debug)
+        name = request.app.name.replace("_", " ").strip()
+        if name.islower():
+            name = name.title()
+        self.TITLE = f"Application {name} cannot handle your request"
+        self.HEADING = E("Application ").strong(name)(
+            " cannot handle your request"
+        )
+        self.title = title
+        self.text = text
+        self.request = request
+        self.exc = exc
+        self.details_open = not getattr(exc, "quiet", False)
+
+    def _head(self) -> None:
+        self.doc._script(tracerite.html.javascript)
+        super()._head()
+
+    def _body(self) -> None:
+        debug = self.request.app.debug
+        route_name = self.request.name or "[route not found]"
+        with self.doc.main:
+            self.doc.h1(f"⚠️ {self.title}").p(self.text)
+            # Show context details if available on the exception
+            context = getattr(self.exc, "context", None)
+            if context:
+                self._key_value_table(
+                    "Issue context", "exception-context", context
+                )
+
+            if not debug:
+                with self.doc.div(id="enduser"):
+                    self.doc.p(ENDUSER_TEXT).p.a("Front Page", href="/")
+                return
+            # Show additional details in debug mode,
+            # open by default for 500 errors
+            with self.doc.details(open=self.details_open, class_="smalltext"):
+                # Show extra details if available on the exception
+                extra = getattr(self.exc, "extra", None)
+                if extra:
+                    self._key_value_table(
+                        "Issue extra data", "exception-extra", extra
+                    )
+
+                self.doc.summary(
+                    "Details for developers (Sanic debug mode only)"
+                )
+                if self.exc:
+                    with self.doc.div(class_="exception-wrapper"):
+                        self.doc.h2(f"Exception in {route_name}:")
+                        self.doc(
+                            html_traceback(self.exc, include_js_css=False)
+                        )
+
+                self._key_value_table(
+                    f"{self.request.method} {self.request.path}",
+                    "request-headers",
+                    self.request.headers,
+                )
+
+    def _key_value_table(
+        self, title: str, table_id: str, data: Mapping[str, Any]
+    ) -> None:
+        with self.doc.div(class_="key-value-display"):
+            self.doc.h2(title)
+            with self.doc.dl(id=table_id, class_="key-value-table smalltext"):
+                for key, value in data.items():
+                    # Reading values may cause a new exception, so suppress it
+                    try:
+                        value = str(value)
+                    except Exception:
+                        value = E.em("Unable to display value")
+                    self.doc.dt.span(key, class_="nobr key").span(": ").dd(
+                        value
+                    )

sanic/pages/styles/BasePage.css

@@ -1,37 +1,93 @@
+/** BasePage **/
+
+:root {
+    --sanic: #ff0d68;
+    --sanic-yellow: #FFE900;
+    --sanic-background: #efeced;
+    --sanic-text: #121010;
+    --sanic-text-lighter: #756169;
+    --sanic-link: #ff0d68;
+    --sanic-block-background: #f7f4f6;
+    --sanic-block-text: #000;
+    --sanic-block-alt-text: #6b6468;
+    --sanic-header-background: #272325;
+    --sanic-header-border: #fff;
+    --sanic-header-text: #fff;
+    --sanic-highlight-background: var(--sanic-yellow);
+    --sanic-highlight-text: var(--sanic-text);
+    --sanic-tab-background: #f7f4f6;
+    --sanic-tab-shadow: #f7f6f6;
+    --sanic-tab-text: #222021;
+    --sanic-tracerite-var: var(--sanic-text);
+    --sanic-tracerite-val: #ff0d68;
+    --sanic-tracerite-type: #6d6a6b;
+}
+
+
+@media (prefers-color-scheme: dark) {
+    :root {
+        --sanic-text: #f7f4f6;
+        --sanic-background: #121010;
+        --sanic-block-background: #0f0d0e;
+        --sanic-block-text: #f7f4f6;
+        --sanic-header-background: #030203;
+        --sanic-header-border: #000;
+        --sanic-highlight-text: var(--sanic-background);
+        --sanic-tab-background: #292728;
+        --sanic-tab-shadow: #0f0d0e;
+        --sanic-tab-text: #aea7ab;
+    }
+}
+
 html {
     font: 16px sans-serif;
-    background: #eee;
+    background: var(--sanic-background);
-    color: #111;
+    color: var(--sanic-text);
+    scrollbar-gutter: stable;
+    overflow: hidden auto;
 }
 
 body {
     margin: 0;
     font-size: 1.25rem;
+    line-height: 125%;
 }
 
 body>* {
     padding: 1rem 2vw;
 }
 
-@media (max-width: 1200px) {
+@media (max-width: 1000px) {
     body>* {
         padding: 0.5rem 1.5vw;
     }
 
-    body {
+    html {
-        font-size: 1rem;
+        /* Scale everything by rem of 6px-16px by viewport width */
+        font-size: calc(6px + 10 * 100vw / 1000);
     }
 }
 
+main {
+    /* Make sure the footer is closer to bottom */
+    min-height: 70vh;
+    /* Generous padding for readability */
+    padding: 1rem 2.5rem;
+}
+
+.smalltext {
+    font-size: 1.0rem;
+}
+
 .container {
     min-width: 600px;
     max-width: 1600px;
 }
 
 header {
-    background: #111;
+    background: var(--sanic-header-background);
-    color: #e1e1e1;
+    color: var(--sanic-header-text);
-    border-bottom: 1px solid #272727;
+    border-bottom: 1px solid var(--sanic-header-border);
     text-align: center;
 }
 
@@ -40,20 +96,17 @@ footer {
     display: flex;
     flex-direction: column;
     font-size: 0.8rem;
-    margin-top: 2rem;
+    margin: 2rem;
+    line-height: 1.5em;
 }
 
 h1 {
     text-align: left;
 }
 
-a:visited {
-    color: inherit;
-}
-
 a {
     text-decoration: none;
-    color: #88f;
+    color: var(--sanic-link);
 }
 
 a:hover,
@@ -62,18 +115,32 @@ a:focus {
     outline: none;
 }
 
-#logo {
-    height: 1.75rem;
-    padding: 0 0.25rem;
-}
 
 span.icon {
     margin-right: 1rem;
 }
 
+#logo-simple {
+    height: 1.75rem;
+    padding: 0 0.25rem;
+}
+
+
 @media (prefers-color-scheme: dark) {
-    html {
+    #logo-simple path:last-child {
-        background: #111;
+        fill: #e1e1e1;
-        color: #ccc;
     }
 }
+
+#sanic pre,
+#sanic code {
+    font-family: "Fira Code",
+        "Source Code Pro",
+        Menlo,
+        Meslo,
+        Monaco,
+        Consolas,
+        Lucida Console,
+        monospace;
+    font-size: 0.8rem;
+}

sanic/pages/styles/DirectoryPage.css

@@ -1,3 +1,4 @@
+/** DirectoryPage **/
 #breadcrumbs>a:hover {
     text-decoration: none;
 }

sanic/pages/styles/ErrorPage.css

@@ -0,0 +1,108 @@
+/** ErrorPage **/
+#enduser {
+    max-width: 30em;
+    margin: 5em auto 5em auto;
+    text-align: justify;
+    /*text-justify: both;*/
+}
+
+#enduser a {
+    color: var(--sanic-blue);
+}
+
+#enduser p:last-child {
+    text-align: right;
+}
+
+summary {
+    margin-top: 3em;
+    color: var(--sanic-text-lighter);
+    cursor: pointer;
+}
+
+.tracerite {
+    --tracerite-var: var(--sanic-tracerite-var);
+    --tracerite-val: var(--sanic-tracerite-val);
+    --tracerite-type: var(--sanic-tracerite-type);
+    --tracerite-exception: var(--sanic);
+    --tracerite-highlight: var(--sanic-yellow);
+    --tracerite-tab: var(--sanic-tab-background);
+    --tracerite-tab-text: var(--sanic-tab-text);
+}
+
+.tracerite>h3 {
+    margin: 0.5rem 0 !important;
+}
+
+#sanic .tracerite .traceback-labels button {
+    font-size: 0.8rem;
+    line-height: 120%;
+    background: var(--tracerite-tab);
+    color: var(--tracerite-tab-text);
+    transition: 0.3s;
+    cursor: pointer;
+}
+
+.tracerite .traceback-labels {
+    padding-top: 5px;
+}
+
+.tracerite .traceback-labels button:hover {
+    filter: contrast(150%) brightness(120%) drop-shadow(0 -0 2px var(--sanic-tab-shadow));
+}
+
+#sanic .tracerite .tracerite-tooltip::before {
+    bottom: 1.75em;
+}
+
+#sanic .tracerite .traceback-details mark span {
+    background: var(--sanic-highlight-background);
+    color: var(--sanic-highlight-text);
+}
+
+header {
+    background: var(--sanic-header-background);
+}
+
+h2 {
+    font-size: 1.3rem;
+    color: var(--sanic-text);
+}
+
+.key-value-display,
+.exception-wrapper {
+    padding: 0.5rem;
+    margin-top: 1rem;
+}
+
+.key-value-display {
+    background-color: var(--sanic-block-background);
+    color: var(--sanic-block-text);
+}
+
+.key-value-display h2 {
+    margin-bottom: 0.2em;
+}
+
+dl.key-value-table {
+    width: 100%;
+    margin: 0;
+    display: grid;
+    grid-template-columns: 1fr 5fr;
+    grid-gap: .3em;
+    white-space: pre-wrap;
+}
+
+dl.key-value-table * {
+    margin: 0;
+}
+
+dl.key-value-table dt {
+    color: var(--sanic-block-alt-text);
+    word-break: break-word;
+}
+
+dl.key-value-table dd {
+    /* Better breaking for cookies header and such */
+    word-break: break-all;
+}

sanic/router.py

@@ -39,13 +39,13 @@ class Router(BaseRouter):
                 extra={"host": host} if host else None,
             )
         except RoutingNotFound as e:
-            raise NotFound("Requested URL {} not found".format(e.path))
+            raise NotFound(f"Requested URL {e.path} not found") from None
         except NoMethod as e:
             raise MethodNotAllowed(
-                "Method {} not allowed for URL {}".format(method, path),
+                f"Method {method} not allowed for URL {path}",
                 method=method,
                 allowed_methods=e.allowed_methods,
-            )
+            ) from None
 
     @lru_cache(maxsize=ROUTER_CACHE_SIZE)
     def get(  # type: ignore
@@ -61,6 +61,7 @@ class Router(BaseRouter):
             correct response
         :rtype: Tuple[ Route, RouteHandler, Dict[str, Any]]
         """
+        __tracebackhide__ = True
         return self._get(path, method, host)
 
     def add(  # type: ignore

setup.py

@@ -112,6 +112,7 @@ requirements = [
     "websockets>=10.0",
     "multidict>=5.0,<7.0",
     "html5tagger>=1.2.1",
+    "tracerite>=1.0.0",
 ]
 
 tests_require = [

tests/test_errorpages.py

@@ -4,7 +4,7 @@ import pytest
 
 from sanic import Sanic
 from sanic.config import Config
-from sanic.errorpages import TextRenderer, guess_mime, exception_response
+from sanic.errorpages import TextRenderer, exception_response, guess_mime
 from sanic.exceptions import NotFound, SanicException
 from sanic.handlers import ErrorHandler
 from sanic.request import Request
@@ -57,7 +57,6 @@ def app():
             raise Exception
         return json({}) if param == "json" else html("")
 
-
     return app
 
 
@@ -314,7 +313,6 @@ def test_fallback_with_content_type_mismatch_accept(app):
         ("*/*", "application/json", "application/json"),
         # App wants text/plain but accept has equal entries for it
         ("text/*,*/plain", None, "text/plain; charset=utf-8"),
-
     ),
 )
 def test_combinations_for_auto(fake_request, accept, content_type, expected):
@@ -428,25 +426,83 @@ def test_config_fallback_bad_value(app):
 @pytest.mark.parametrize(
     "route_format,fallback,accept,expected",
     (
-        ("json", "html", "*/*", "The client accepts */*, using 'json' from fakeroute"),
+        (
-        ("json", "auto", "text/html,*/*;q=0.8", "The client accepts text/html, using 'html' from any"),
+            "json",
-        ("json", "json", "text/html,*/*;q=0.8", "The client accepts */*;q=0.8, using 'json' from fakeroute"),
+            "html",
-        ("", "html", "text/*,*/plain", "The client accepts text/*, using 'html' from FALLBACK_ERROR_FORMAT"),
+            "*/*",
-        ("", "json", "text/*,*/*", "The client accepts */*, using 'json' from FALLBACK_ERROR_FORMAT"),
+            "The client accepts */*, using 'json' from fakeroute",
-        ("", "auto", "*/*,application/json;q=0.5", "The client accepts */*, using 'json' from request.accept"),
+        ),
-        ("", "auto", "*/*", "The client accepts */*, using 'json' from content-type"),
+        (
-        ("", "auto", "text/html,text/plain", "The client accepts text/plain, using 'text' from any"),
+            "json",
-        ("", "auto", "text/html,text/plain;q=0.9", "The client accepts text/html, using 'html' from any"),
+            "auto",
-        ("html", "json", "application/xml", "No format found, the client accepts [application/xml]"),
+            "text/html,*/*;q=0.8",
+            "The client accepts text/html, using 'html' from any",
+        ),
+        (
+            "json",
+            "json",
+            "text/html,*/*;q=0.8",
+            "The client accepts */*;q=0.8, using 'json' from fakeroute",
+        ),
+        (
+            "",
+            "html",
+            "text/*,*/plain",
+            "The client accepts text/*, using 'html' from FALLBACK_ERROR_FORMAT",
+        ),
+        (
+            "",
+            "json",
+            "text/*,*/*",
+            "The client accepts */*, using 'json' from FALLBACK_ERROR_FORMAT",
+        ),
+        (
+            "",
+            "auto",
+            "*/*,application/json;q=0.5",
+            "The client accepts */*, using 'json' from request.accept",
+        ),
+        (
+            "",
+            "auto",
+            "*/*",
+            "The client accepts */*, using 'json' from content-type",
+        ),
+        (
+            "",
+            "auto",
+            "text/html,text/plain",
+            "The client accepts text/plain, using 'text' from any",
+        ),
+        (
+            "",
+            "auto",
+            "text/html,text/plain;q=0.9",
+            "The client accepts text/html, using 'html' from any",
+        ),
+        (
+            "html",
+            "json",
+            "application/xml",
+            "No format found, the client accepts [application/xml]",
+        ),
         ("", "auto", "*/*", "The client accepts */*, using 'text' from any"),
         ("", "", "*/*", "No format found, the client accepts [*/*]"),
         # DEPRECATED: remove in 24.3
-        ("", "auto", "*/*", "The client accepts */*, using 'json' from request.json"),
+        (
+            "",
+            "auto",
+            "*/*",
+            "The client accepts */*, using 'json' from request.json",
+        ),
     ),
 )
-def test_guess_mime_logging(caplog, fake_request, route_format, fallback, accept, expected):
+def test_guess_mime_logging(
+    caplog, fake_request, route_format, fallback, accept, expected
+):
     class FakeObject:
         pass
+
     fake_request.route = FakeObject()
     fake_request.route.name = "fakeroute"
     fake_request.route.extra = FakeObject()
@@ -466,6 +522,8 @@ def test_guess_mime_logging(caplog, fake_request, route_format, fallback, accept
     with caplog.at_level(logging.DEBUG, logger="sanic.root"):
         guess_mime(fake_request, fallback)
 
-    logmsg, = [r.message for r in caplog.records if r.funcName == "guess_mime"]
+    (logmsg,) = [
+        r.message for r in caplog.records if r.funcName == "guess_mime"
+    ]
 
     assert logmsg == expected

tests/test_exceptions.py

@@ -23,11 +23,11 @@ from sanic.exceptions import (
 from sanic.response import text
 
 
-def dl_to_dict(soup, css_class):
+def dl_to_dict(soup, dl_id):
     keys, values = [], []
-    for dl in soup.find_all("dl", {"class": css_class}):
+    for dl in soup.find_all("dl", {"id": dl_id}):
         for dt in dl.find_all("dt"):
-            keys.append(dt.text.strip())
+            keys.append(dt.text.split(":", 1)[0])
         for dd in dl.find_all("dd"):
             values.append(dd.text.strip())
     return dict(zip(keys, values))
@@ -194,10 +194,7 @@ def test_handled_unhandled_exception(exception_app):
     assert "Internal Server Error" in soup.h1.text
 
     message = " ".join(soup.p.text.split())
-    assert message == (
+    assert "The application encountered an unexpected error" in message
-        "The server encountered an internal error and "
-        "cannot complete your request."
-    )
 
 
 def test_exception_in_exception_handler(exception_app):
@@ -299,7 +296,7 @@ def test_contextual_exception_context(debug):
 
     _, response = app.test_client.post("/coffee/html", debug=debug)
     soup = BeautifulSoup(response.body, "html.parser")
-    dl = dl_to_dict(soup, "context")
+    dl = dl_to_dict(soup, "exception-context")
     assert response.status == 418
     assert "Sorry, I cannot brew coffee" in soup.find("p").text
     assert dl == {"foo": "bar"}
@@ -340,7 +337,7 @@ def test_contextual_exception_extra(debug):
 
     _, response = app.test_client.post("/coffee/html", debug=debug)
     soup = BeautifulSoup(response.body, "html.parser")
-    dl = dl_to_dict(soup, "extra")
+    dl = dl_to_dict(soup, "exception-extra")
     assert response.status == 418
     assert "Found bar" in soup.find("p").text
     if debug:

tests/test_exceptions_handler.py

@@ -123,10 +123,10 @@ def test_html_traceback_output_in_debug_mode(exception_handler_app: Sanic):
     assert "handler_4" in html
     assert "foo = bar" in html
 
-    summary_text = " ".join(soup.select(".summary")[0].text.split())
+    summary_text = soup.select("h3")[0].text
-    assert (
+    assert "NameError: name 'bar' is not defined" == summary_text
-        "NameError: name 'bar' is not defined while handling path /4"
+    request_text = soup.select("h2")[-1].text
-    ) == summary_text
+    assert "GET /4" == request_text
 
 
 def test_inherited_exception_handler(exception_handler_app: Sanic):
@@ -146,11 +146,10 @@ def test_chained_exception_handler(exception_handler_app: Sanic):
     assert "handler_6" in html
     assert "foo = 1 / arg" in html
     assert "ValueError" in html
+    assert "GET /6" in html
 
-    summary_text = " ".join(soup.select(".summary")[0].text.split())
+    summary_text = soup.select("h3")[0].text
-    assert (
+    assert "ZeroDivisionError: division by zero" == summary_text
-        "ZeroDivisionError: division by zero while handling path /6/0"
-    ) == summary_text
 
 
 def test_exception_handler_lookup(exception_handler_app: Sanic):

tests/test_headers.py

@@ -50,7 +50,7 @@ def raised_ceiling():
         ),
         (
             'form-data; name="foo"; value="%22\\%0D%0A"',
-            ("form-data", {"name": "foo", "value": '\"\\\n'})
+            ("form-data", {"name": "foo", "value": '"\\\n'}),
         ),
         # <input type=file name="foo&quot;;bar\"> with Unicode filename!
         (