`, favicon, and body of `Root()` to\nmatch your app's existing `index.html`, and stamp anything else your shell\nreferences directly (images, css) with `immutableFileUrl()`.\n\n1. Create `frontend/root.tsx`:\n\n```tsx\n/** @jsxImportSource npm:hono@4/jsx */\nimport { raw } from \"npm:hono@4/html\";\nimport { immutableFileUrl } from \"https://esm.town/v/std/utils/index.ts\";\n\n// The HTML shell for the app. It is never cached, so immutableFileUrl can stamp\n// the current val version into each asset URL — the browser caches those\n// immutably, and publishing the val changes the URLs, refetching exactly once.\nexport function Root() {\n return (\n <>\n {raw(\"<!DOCTYPE html>\")}\n <html lang=\"en\">\n <head>\n <meta charSet=\"UTF-8\" />\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\" />\n <title>React Hono Val Town Starter

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\n {img\n ? $\"\"$ \n :

}\n

\n \n {pick.name}\n \n

\n {Math.round(pick.match * 100)}% match\n ·\n {pick.genres.slice(0, 2).join(\", \")}\n

Popularity {pick.popularity} — under-discovered

\n Pick: \n {pick.trackName}\n

\n \n

\n {pick.previewUrl\n ?

\n );\n}\n","/** @jsxImportSource https://esm.sh/react@18.2.0 */\nimport { RadarChart } from \"./RadarChart.tsx\";\n\ninterface Axis {\n label: string;\n value: number;\n}\n\ninterface TrackInfo {\n name: string;\n uri: string;\n previewUrl: string | null;\n}\n\ninterface Pick {\n id: string;\n name: string;\n images: { url: string }[];\n popularity: number;\n genres: string[];\n previewUrl: string | null;\n match: number;\n radar: Axis[];\n tracks: TrackInfo[];\n}\n\nfunction trackUrl(uri: string): string {\n const id = uri.split(\":\")[2] ?? uri;\n return `https://open.spotify.com/track/${id}`;\n}\n\nexport function ArtistCard({ pick, profile }: { pick: Pick; profile: Axis[] }) {\n const img = pick.images?.[0]?.url;\n const spotifyUrl = `https://open.spotify.com/artist/${pick.id}`;\n return (\n

\n {img\n ? $\"\"$ \n :

}\n

\n \n {pick.name}\n \n

\n {Math.round(pick.match * 100)}% match\n ·\n {pick.genres.slice(0, 2).join(\", \") || \"—\"}\n

Popularity {pick.popularity}

\n\n

\n \n ♪\n {t.name}\n \n

\n\n

\n \n

\n );\n}\n","createdAt",["D",1787420610876],"branchVersion","branchId","dc1f9fe4-aa8c-400d-87f3-9d22e6847153","id","f8c773d7-7a4a-4d5b-84e7-ccf2b3929d80","discovery-radar",["D",1787417498284],"deletedAt","legacyEnvVars","privacy","public","httpPrivacy","description","Spotify discovery with taste radar + weekly playlist refresh","imageUrl","e6d51557-2988-4ce3-bf61-63d827903a6c","pinnedFileId","01a02a62-92f6-771d-907a-be2483e744c9","pinPreview",true,"pinMigrated","screenshotVersion","likeCount",0,"orgId","3ebf4d50-fe40-465b-915c-bd543c8a8608","tursoName","f8c773d77a4a4d5b84e7ccf2b3929d80","tursoHostname","f8c773d77a4a4d5b84e7ccf2b3929d80-val-town.aws-us-east-2.turso.io","tursoMeasuredAt",["D",1789502486629],"pinned","userPerm","r","valPerm","blobPerm","rw","emailPerm","sqlitePerm","projectPerm","telemetryPerm","user",{"_107":106,"_114":110},"org",{"_107":106,"_108":-5,"_109":110,"_19":62,"_111":112,"_113":31},"branch",{"_13":96,"_38":97,"_50":49,"_98":51,"_99":-5,"_100":-5,"_101":-5,"_102":-5,"_103":-5,"_104":52,"_105":106},"isOwned",90,"main","projectId","forkedBranchId","forkedBranchVersion","forkedProjectPrivacy","forkedProjectId","forkedProjectOrgId","projectName","userHandle","test_account_001","handle","displayName","avatar","https://img.clerk.com/eyJ0eXBlIjoiZGVmYXVsdCIsImlpZCI6Imluc18yTm10cGhQUklwU0tqZHNiOHNnNGd2ZjJURFUiLCJyaWQiOiJ1c2VyXzJabHpKOGNWSmhqcWduM3VVV0xTUGlicVprayJ9","tier","free","canRestrictVals","profileImageUrl","branchName","","adoptOrgId",{"_50":51,"_38":52,"_45":314,"_54":-5,"_55":31,"_56":57,"_58":57,"_59":60,"_61":-5,"_19":62,"_63":64,"_65":66,"_67":-5,"_68":-5,"_69":70,"_71":72,"_73":74,"_75":76,"_77":315,"_79":-5,"_80":81,"_82":81,"_83":84,"_85":84,"_86":84,"_87":81,"_88":81,"_89":316,"_91":317,"_93":318,"_95":31},"tree",[198,200,208,212,213,214],"files",[198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214],"counts",{"_187":70,"_188":165,"_189":70,"_190":191,"_192":193},"contents",[137,138,139,140,141,142],"upstreamProject","upstreamBranch","emptyEnvVars","flags",[],"hasHttpFiles","grants","orgs","customDomains",{},{"_50":181,"_38":182,"_36":183,"_145":-5,"_48":49,"_47":184,"_147":66,"_45":185,"_13":70,"_40":174,"_42":-5,"_30":31,"_152":-5,"_33":186},{"_50":176,"_38":177,"_36":178,"_145":-5,"_48":49,"_47":165,"_147":66,"_45":179,"_13":70,"_40":174,"_42":-5,"_30":31,"_152":-5,"_33":180},{"_50":169,"_38":170,"_36":171,"_145":-5,"_48":49,"_47":172,"_147":66,"_45":173,"_13":70,"_40":174,"_42":-5,"_30":31,"_152":-5,"_33":175},{"_50":162,"_38":163,"_36":164,"_145":-5,"_48":49,"_47":165,"_147":66,"_45":166,"_13":70,"_40":26,"_42":167,"_30":31,"_152":-5,"_33":168},{"_50":154,"_38":155,"_36":156,"_145":-5,"_48":49,"_47":157,"_147":31,"_45":158,"_13":159,"_40":26,"_42":160,"_30":31,"_152":-5,"_33":161},{"_50":143,"_38":144,"_36":64,"_145":-5,"_48":49,"_47":146,"_147":31,"_45":148,"_13":149,"_40":150,"_42":151,"_30":31,"_152":52,"_33":153},"942e4d43-8e70-45ae-934e-3e687a248e5b","index.ts","parentId",52,"latest",["D",1787420592794],9,"http","import { serveImmutableFile } from \"https://esm.town/v/std/utils/index.ts\";\nimport { Context, Hono } from \"npm:hono\";\nimport { getCookie, setCookie } from \"npm:hono/cookie\";\nimport { Root } from \"./frontend/root.tsx\";\nimport { StoredUser, getUser, init, upsertUser } from \"./lib/db.ts\";\nimport { authorizeUrl, exchangeCode } from \"./lib/spotify.ts\";\nimport { computeProfile, discover, updateDiscoveryPlaylist } from \"./lib/taste.ts\";\n\nawait init();\n\nconst app = new Hono();\nconst COOKIE = \"discovery_radar_user\";\n\nasync function getSessionUser(c: Context): Promise {\n const id = getCookie(c, COOKIE);\n return id ? getUser(id) : null;\n}\n\n// Serve the (never-cached) HTML shell at the root\napp.get(\"/\", (c) => c.html(Root()));\n\n// Serve frontend files, cached immutably\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\n\n// ---- Spotify OAuth ----\napp.get(\"/auth/login\", (c) => {\n const state = crypto.randomUUID();\n setCookie(c, \"discovery_radar_state\", state, { path: \"/\", httpOnly: true, sameSite: \"Lax\" });\n return c.redirect(authorizeUrl(state));\n});\n\napp.get(\"/auth/callback\", async (c) => {\n const code = c.req.query(\"code\");\n if (!code) return c.text(\"Missing authorization code\", 400);\n try {\n const tokens = await exchangeCode(code);\n const me = await (await fetch(\"https://api.spotify.com/v1/me\", {\n headers: { authorization: `Bearer ${tokens.access_token}` },\n })).json();\n await upsertUser({\n spotifyId: me.id,\n displayName: me.display_name ?? \"Spotify user\",\n accessToken: tokens.access_token,\n refreshToken: tokens.refresh_token ?? \"\",\n expiresAt: Date.now() + tokens.expires_in * 1000,\n });\n setCookie(c, COOKIE, me.id, {\n path: \"/\",\n httpOnly: true,\n sameSite: \"Lax\",\n maxAge: 60 * 60 * 24 * 30,\n });\n return c.redirect(\"/\");\n } catch (e) {\n console.error(\"callback failed\", e);\n return c.text(\"Spotify auth failed: \" + (e as Error).message, 500);\n }\n});\n\napp.post(\"/auth/logout\", (c) => {\n setCookie(c, COOKIE, \"\", { path: \"/\", httpOnly: true, sameSite: \"Lax\", maxAge: 0 });\n return c.redirect(\"/\");\n});\n\n// ---- API ----\napp.get(\"/api/me\", async (c) => {\n const u = await getSessionUser(c);\n return c.json(u ? { connected: true, displayName: u.displayName } : { connected: false });\n});\n\napp.get(\"/api/profile\", async (c) => {\n const u = await getSessionUser(c);\n if (!u) return c.json({ error: \"unauthorized\" }, 401);\n return c.json({ profile: await computeProfile(u) });\n});\n\napp.get(\"/api/discover\", async (c) => {\n const u = await getSessionUser(c);\n if (!u) return c.json({ error: \"unauthorized\" }, 401);\n const profile = await computeProfile(u);\n const obscurity = parseFloat(c.req.query(\"obscurity\") ?? \"\");\n const genre = c.req.query(\"genre\");\n const picks = await discover(u, profile, {\n obscurity: Number.isFinite(obscurity) ? obscurity : undefined,\n genres: genre ? [genre] : undefined,\n });\n return c.json({ profile, genres: profile.map((a) => a.label), picks });\n});\n\napp.post(\"/api/save\", async (c) => {\n const u = await getSessionUser(c);\n if (!u) return c.json({ error: \"unauthorized\" }, 401);\n try {\n const body = await c.req.json<{ trackUris: string[] }>();\n const playlistId = await updateDiscoveryPlaylist(u, body.trackUris ?? []);\n return c.json({ ok: true, playlistId });\n } catch (e) {\n const msg = (e as Error).message || \"save failed\";\n console.error(\"save failed:\", e);\n return c.json(\n { ok: false, error: \"Spotify blocked playlist access: \" + msg },\n 502,\n );\n }\n});\n\n// Unwrap and rethrow Hono errors as the original error\napp.onError((err) => Promise.reject(err));\n\nexport default app.fetch;\n","label",[144],"3f3b0743-c3c9-408e-bb21-1acefa75e8a1","README.md","01a02a62-92f6-771d-907a-b81da57860c2",39,["D",1787419507333],4,"# 🎧 Discovery Radar\n\nA personal Spotify discovery app that breaks you out of the same 50 artists.\n\nIt computes **your sound profile** (a radar chart of the genres that dominate\nyour library), then digs deep into those genres to surface **under-discovered**\nacts — showing how closely each one's genres line up with yours, with a\n30-second preview so you can audition in the browser. Save your picks to a\nSpotify playlist, or let the weekly cron refresh it so it never goes stale.\n\n## How it works\n\n```mermaid\ngraph LR\n Browser -->|\"Connect Spotify\"| Hono[\"index.ts
(Hono + OAuth)\"]\n Hono -->|stores tokens| DB[(SQLite)]\n Hono -->|computeProfile + discover| SP[\"Spotify API\"]\n SP -->|top artists + genre search| Hono\n Hono -->|radar data + picks| React[\"React app
(radar charts)\"]\n Cron[\"cron/refresh.ts
(weekly)\"] -->|refresh playlist| SP\n```\n\n- `index.ts` — Hono server: Spotify OAuth, session cookie, `/api/me`,\n `/api/profile`, `/api/discover`, `/api/save`.\n- `lib/spotify.ts` — OAuth (authorization-code flow) + authed API client with\n token refresh.\n- `lib/taste.ts` — taste profile, related-artist discovery, playlist writer.\n- `lib/db.ts` — SQLite storage for per-user Spotify tokens.\n- `frontend/` — React app with an SVG radar-chart component\n (`RadarChart.tsx`) that overlays each candidate's sound on yours.\n- `cron/refresh.ts` — weekly job that refreshes each user's \"Discovery Radar\"\n playlist (Sundays 12:00 UTC).\n\n## Setup\n\n1. Create a Spotify app at\n (Dashboard → Create app).\n2. Add this as a **Redirect URI** in the app's settings:\n `https://discovery-radar.val.run/auth/callback`\n3. Set the two env vars below.\n\n👉 Add SPOTIFY_CLIENT_ID here: https://www.val.town/x/test_account_001/discovery-radar/environment-variables?key=SPOTIFY_CLIENT_ID\n\n👉 Add SPOTIFY_CLIENT_SECRET here: https://www.val.town/x/test_account_001/discovery-radar/environment-variables?key=SPOTIFY_CLIENT_SECRET\n\n`SPOTIFY_REDIRECT_URI` is optional — it defaults to the callback URL above.\n\n4. Open the app, hit **Connect Spotify**, and authorize. Your taste profile and\n a grid of under-discovered artists appear. Hit **Save top picks** to write\n them to a private \"Discovery Radar\" playlist.\n\n## Notes\n\n- **Discovery uses only `/me/top` + `/v1/search`.** Spotify currently 403/404s\n the richer endpoints (related-artists, audio-features, browse, and even the\n recommendations engine) for new/unreviewed apps. So the radar is built from\n genre tags, and discovery is genre-search paged deep enough to reach small\n acts. This is by design and resilient, not a limitation you need to fix.\n- The under-discovered filter keeps artists with popularity between ~5 and 45.\n- The weekly cron refreshes the playlist for every connected user.\n- **Save-to-playlist needs the `playlist-modify-*` scopes on the user's token.**\n If \"Save\" errors with \"Spotify blocked playlist access\", the granted token is\n missing those scopes — disconnect and click Connect Spotify again to re-consent.\n- Tokens are stored per Spotify user in the val's SQLite DB and refreshed\n automatically.\n",[155],"4fe8db74-919d-4686-9be5-883aad74c74f","CHANGELOG.md","01a02a62-92f6-771d-907a-b61ebd4f10fe",1,["D",1787417498284],"# Changelog\n\n## 2026-07-30 — Immutable asset caching\n\nFrontend files are now served at version-addressed URLs\n(`/__immutable/45/frontend/index.tsx`) with\n`Cache-Control: public, max-age=31536000, immutable`, so repeat visits load the\nwhole client graph from the browser cache — roughly 3× faster (~665ms → ~157ms\nmeasured). Publishing your val bumps its version, which changes every URL, so\ncaches invalidate automatically. Old-version URLs return 404 after a publish\n(like Next.js build assets); a reload picks up the new version.\n\nWhat changed in the template:\n\n- `frontend/index.html` → [`frontend/root.tsx`](/frontend/root.tsx): the HTML\n shell is now JSX and stamps asset URLs with `immutableFileUrl()`\n- [`index.ts`](/index.ts): serves `Root()` at `/`, and one\n `app.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path))` route\n serves all frontend files\n\n### Upgrading an existing remix\n\nYour copy of this template doesn't update automatically. Two options:\n\n**Minimal (most of the benefit):** point both routes at `serveImmutableFile` —\nyour existing bare URLs redirect into versioned space, the new route serves\nthem, and the whole module graph gets cached (costs one redirect per page view):\n\n```ts\nimport { serveImmutableFile } from \"https://esm.town/v/std/utils/index.ts\";\n\napp.get(\"/__immutable/*\", (c) => serveImmutableFile(c.req.path));\napp.get(\"/frontend/**/*\", (c) => serveImmutableFile(c.req.path)); // was serveFile\n```\n\n**Full upgrade (also removes the redirect):** three self-contained steps —\nno other files needed. Adjust the ``, favicon, and body of `Root()` to\nmatch your app's existing `index.html`, and stamp anything else your shell\nreferences directly (images, css) with `immutableFileUrl()`.\n\n1. Create `frontend/root.tsx`:\n\n```tsx\n/** @jsxImportSource npm:hono@4/jsx */\nimport { raw } from \"npm:hono@4/html\";\nimport { immutableFileUrl } from \"https://esm.town/v/std/utils/index.ts\";\n\n// The HTML shell for the app. It is never cached, so immutableFileUrl can stamp\n// the current val version into each asset URL — the browser caches those\n// immutably, and publishing the val changes the URLs, refetching exactly once.\nexport function Root() {\n return (\n <>\n {raw(\"<!DOCTYPE html>\")}\n <html lang=\"en\">\n <head>\n <meta charSet=\"UTF-8\" />\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\" />\n <title>React Hono Val Town Starter\n

Diff · v54