Use structured logging with Pino throughout your application. Covers log levels, context, and workflow-safe logging patterns.
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Use structured logging with Pino throughout your application. Covers log levels, context, and workflow-safe logging patterns.
See:
using-logging in Fullstack RecipesImport the logger and use it throughout your application:
import { logger } from "@/lib/common/logger";
// Info level for normal operations
logger.info("Server started", { port: 3000 });
// Warn level for recoverable issues
logger.warn("Rate limit reached", { endpoint: "/api/chat" });
// Error level with Error objects
logger.error(err, "Failed to process request");
// Debug level for development troubleshooting
logger.debug("Cache miss", { key: "user:123" });
Always include context as the first argument for structured logs:
// Context object first, message second
logger.info({ userId: "123", action: "login" }, "User logged in");
// For errors, pass the error first
logger.error({ err, userId: "123", endpoint: "/api/chat" }, "Request failed");
Use appropriate levels for different scenarios:
| Level | When to Use |
|---|---|
trace | Detailed debugging (rarely used) |
debug | Development troubleshooting |
info | Normal operations, business events |
warn | Recoverable issues, deprecation warnings |
error | Failures that need attention |
fatal | Critical failures, app cannot continue |
Set the PINO_LOG_LEVEL environment variable:
# Show all logs including debug
PINO_LOG_LEVEL="debug"
# Production: only warnings and errors
PINO_LOG_LEVEL="warn"
Default is info if not set.
import { logger } from "@/lib/common/logger";
export async function POST(request: Request) {
const start = Date.now();
try {
const result = await processRequest(request);
logger.info(
{ duration: Date.now() - start, status: 200 },
"Request completed",
);
return Response.json(result);
} catch (err) {
logger.error({ err, duration: Date.now() - start }, "Request failed");
return Response.json({ error: "Internal error" }, { status: 500 });
}
}
Workflow functions run in a restricted environment. Use the logger step wrapper:
// src/workflows/chat/steps/logger.ts
import { logger } from "@/lib/common/logger";
export async function log(
level: "info" | "warn" | "error" | "debug",
message: string,
data?: Record<string, unknown>,
): Promise<void> {
"use step";
if (data) {
logger[level](data, message);
} else {
logger[level](message);
}
}
Then use it in workflows:
import { log } from "./steps/logger";
export async function chatWorkflow({ chatId }) {
"use workflow";
await log("info", "Workflow started", { chatId });
}