feat(landing): Python logging levels guide

apps/landing/src/components/docs/LanguageTabs.astro

@@ -16,13 +16,15 @@ interface Tab {
 interface Props {
     tabs: Tab[];
     label?: string;
+    /** Storage key for the remembered pick. Groups that aren't a language choice pass their own. */
+    group?: string;
 }
 
-const { tabs, label = "Language" } = Astro.props;
+const { tabs, label = "Language", group = "maple-docs-language" } = Astro.props;
 const hasLogo = (id: string): id is LogoId => (LOGO_IDS as readonly string[]).includes(id);
 ---
 
-<div class="lt" data-lang-tabs="maple-docs-language">
+<div class="lt" data-lang-tabs={group}>
     <div class="lt__rail" role="tablist" aria-label={label}>
         {tabs.map((tab, index) => (
             <button

apps/landing/src/content/docs/guides/instrumentation-python.md

@@ -236,7 +236,7 @@ import logging
 logging.getLogger(__name__).warning("Payment retry for order %s", order_id)
 ```
 
-The root logger's level still applies. Python defaults it to `WARNING`, so call `logging.basicConfig(level=logging.INFO)` or set the level yourself to send `INFO` records.
+The root logger's level still applies. Python defaults it to `WARNING`, so call `logging.getLogger().setLevel(logging.INFO)` to send `INFO` records. `logging.basicConfig(level=...)` does nothing once the root logger has a handler, so after `import telemetry` it no longer sets the level. See [Python logging levels](/guides/python-logging-levels) for per-module and per-handler levels.
 
 ## Verify
 

apps/landing/src/lib/guide-highlight.ts

@@ -1,7 +1,7 @@
 // Tiny highlighter for guide code blocks. The token classes match the colors a
 // guide uses in its diagrams (metric name, labels, value), so a block reads the
 // same way as the annotated example above it. Style the `tok-*` classes on the page.
-export type GuideLang = "exposition" | "promql" | "yaml" | "python" | "typescript" | "go" | "rust" | "java" | "csharp";
+export type GuideLang = "exposition" | "promql" | "yaml" | "console" | "python" | "typescript" | "go" | "rust" | "java" | "csharp";
 
 const escape = (s: string) => s.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
 const span = (cls: string, text: string) => `<span class="tok-${cls}">${escape(text)}</span>`;
@@ -71,12 +71,23 @@ const python = (code: string) =>
     tokenize(code, [
         [/#.*/y, (m) => span("comment", m[0])],
         [/"[^"\n]*"/y, (m) => span("labels", m[0])],
-        [/\b(?:from|import|def|with|as|return)\b/y, (m) => span("fn", m[0])],
+        [/\b(?:from|import|def|with|as|return|if|else|for|in|not|is|None|True|False|lambda|try|except|raise)\b/y, (m) => span("fn", m[0])],
         [/\b(?:Counter|Gauge|Histogram|Summary)\b/y, (m) => span("name", m[0])],
         [/\b\d+(?:\.\d+)?\b/y, (m) => span("value", m[0])],
         [/[a-zA-Z_]\w*/y, (m) => escape(m[0])],
     ]);
 
+// Terminal sessions: "$ command  # note" lines; every other line is program output.
+const consoleSession = (code: string) =>
+    code
+        .split("\n")
+        .map((line) => {
+            const cmd = /^(\$ )(.*?)(\s+#.*)?$/.exec(line);
+            if (!cmd) return escape(line);
+            return span("comment", cmd[1]) + span("fn", cmd[2]) + (cmd[3] ? span("comment", cmd[3]) : "");
+        })
+        .join("\n");
+
 // Brace languages share one tokenizer: comments, strings, keywords, the metric
 // classes (orange, like metric names), numbers.
 const braces = (keywords: string) => {
@@ -99,4 +110,4 @@ const java = braces("import|public|static|final|class|void|new|try|throws");
 const csharp = braces("using|var|new|await");
 
 export const highlight = (code: string, lang: GuideLang) =>
-    ({ exposition, promql, yaml, python, typescript, go, rust, java, csharp })[lang](code);
+    ({ exposition, promql, yaml, console: consoleSession, python, typescript, go, rust, java, csharp })[lang](code);

apps/landing/src/pages/guides/index.astro

@@ -73,6 +73,13 @@ const investigationGuides = [
         description: "Measure the right latency clock, isolate the slow requests, and trace a regression to the release and operation responsible.",
         read: "14 min",
     },
+    {
+        href: "/guides/python-logging-levels",
+        label: "Python",
+        title: "Python logging levels and how to set them",
+        description: "The five levels and when to use each, why info() prints nothing by default, and how to set the level with basicConfig, a --log-level flag or LOG_LEVEL.",
+        read: "6 min",
+    },
 ];
 
 const fieldNotes = (await getCollection("blog") as BlogPost[])

apps/landing/src/pages/llms.txt.ts

@@ -110,6 +110,7 @@ export const GET: APIRoute = ({ site }) => {
 		`- [What is OpenTelemetry?](${url("/opentelemetry")})`,
 		`- [Best open-source observability tools](${url("/best-open-source-observability-tools")})`,
 		`- [Dynatrace pricing, explained](${url("/guides/dynatrace-pricing")})`,
+		`- [Python logging levels and how to set them](${url("/guides/python-logging-levels")})`,
 		"",
 
 		"## Maple API",