{"record":{"id":"4c2f9140a6600819","repo":"sveltejs/kit","slug":"to-suppress-or-handle-this-error-implement-nam","errorCode":null,"errorMessage":"To suppress or handle this error, implement `${name}` in https://svelte.dev/docs/kit/configuration#prerender","messagePattern":"To suppress or handle this error, implement `(.+?)` in https://svelte\\.dev/docs/kit/configuration#prerender","errorType":"console","errorClass":null,"httpStatus":null,"severity":"error","filePath":"packages/kit/src/core/postbuild/prerender.js","lineNumber":107,"sourceCode":"\t\t\tconst message = format(details);\n\t\t\tlog.error(`\\n${message}\\n`);\n\t\t}\n\n\t\tswitch (input) {\n\t\t\tcase 'fail':\n\t\t\t\treturn (details) => {\n\t\t\t\t\tlog_failure(details);\n\t\t\t\t\tthrow_handled();\n\t\t\t\t};\n\t\t\tcase 'warn':\n\t\t\t\treturn log_failure;\n\t\t\tcase 'ignore':\n\t\t\t\treturn noop;\n\t\t\tcase undefined: {\n\t\t\t\treturn (details) => {\n\t\t\t\t\tlog_failure(details);\n\n\t\t\t\t\tlog.err(\n\t\t\t\t\t\t`To suppress or handle this error, implement \\`${name}\\` in https://svelte.dev/docs/kit/configuration#prerender\\n`\n\t\t\t\t\t);\n\n\t\t\t\t\tthrow_handled();\n\t\t\t\t};\n\t\t\t}\n\t\t\tdefault:\n\t\t\t\treturn (details) => {\n\t\t\t\t\tconst message = format(details);\n\n\t\t\t\t\ttry {\n\t\t\t\t\t\t// @ts-expect-error TS thinks T might be of a different kind, but it's not\n\t\t\t\t\t\tinput({ ...details, message });\n\t\t\t\t\t} catch (error) {\n\t\t\t\t\t\tlog.prettyError(error, import.meta.dirname);\n\t\t\t\t\t\tthrow_handled();\n\t\t\t\t\t}\n\t\t\t\t};","sourceCodeStart":89,"sourceCodeEnd":125,"githubUrl":"https://github.com/sveltejs/kit/blob/03f1687fe612ce3d2d9131139b5b188d9cf90c64/packages/kit/src/core/postbuild/prerender.js#L89-L125","documentation":"During `vite build` prerendering, when a prerender error occurs and no prerender.<errorHandler> option is configured, SvelteKit logs the failure and this hint telling you to implement the named handler (e.g. handleHttpError, handleMissingId) in svelte.config.js, then aborts the build via the internal '__handled__' error.","triggerScenarios":"Prerendering hits an error (HTTP error response, missing id in an anchor, entry-generator mismatch, not-prerendered route, or invalid URL fetched from a page) while svelte.config.js has no corresponding `prerender.handle*` callback defined.","commonSituations":"A page links to a missing route or fetches a non-200 URL during prerender; CI builds fail with the hint message after the logged failure details.","solutions":["Read the failure details logged just above the hint to find the offending route/link.","Implement the named handler (e.g. prerender.handleHttpError) in svelte.config.js returning 'fail', 'warn', or 'ignore' as desired.","Fix the underlying broken link or endpoint so the error disappears."],"exampleFix":"// before (svelte.config.js)\nprerender: { handleHttpError: undefined }\n// after\nprerender: {\n  handleHttpError: ({ path, message }) => {\n    if (path.startsWith('/legacy')) return; // ignore\n    throw new Error(message);\n  }\n}","handlingStrategy":"validation","validationCode":"// svelte.config.js — ensure every prerender error class has an explicit handler\nconst required = ['handleHttpError', 'handleMissingId', 'handleEntryGeneratorMismatch', 'handleNotPrerenderedRoute', 'handleInvalidUrl'];\nfor (const k of required) {\n  if (!(k in config.prerender)) console.warn(`prerender.${k} is not configured`);\n}","typeGuard":null,"tryCatchPattern":"try {\n  await build();\n} catch (err) {\n  if (err.message.includes('To suppress or handle this error')) {\n    console.error('Configure prerender handlers in svelte.config.js; see logged failure details above');\n  }\n  throw err;\n}","preventionTips":["Explicitly configure all prerender.handle* options instead of relying on defaults.","Fix broken links/404 endpoints reported during prerender rather than silencing them globally.","Run prerender-heavy builds locally before CI."],"tags":["prerender","config","build","ssg"],"backgroundTag":"prerender-error-handler-missing","analyzedSha":"03f1687fe612ce3d2d9131139b5b188d9cf90c64","analyzedAt":"2026-09-02T02:01:50.504Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-09T06:17:21.866Z"}