console | Andromeda

Andromeda follows the WHATWG Console standard, so the API will be familiar to anyone coming from browsers or Node.js.

Output Methods

console.log("Hello, World!");
console.info("App started");
console.warn("Deprecated API");
console.error("Network failure");
console.debug("Cache hit", { key: "x", ttl: 60 });

All methods accept any number of arguments — objects are inspected, arrays are formatted, and primitives stringified.

printf-style formatting

console.log("User %s is %d years old", "John", 25);

Supported specifiers: %s, %d / %i, %f, %o / %O, %j, %c.

Styled output (`%c`)

%c consumes one CSS-style argument and applies it to the substring that follows:

console.log(
  "%cHello%c %cAndromeda",
  "color:red;font-weight:bold",
  "",
  "color:blue",
);

Common properties: color, background, font-weight, font-style, text-decoration, padding.

Assertions

console.assert(value > 0, "Value should be positive, got %d", value);

If the assertion fails, the remaining arguments are logged as an error.

Counts

console.count(); // default: 1
console.count("login"); // login: 1
console.count("login"); // login: 2
console.countReset("login");

Timers

console.time("query");
await runQuery();
console.timeLog("query", "partial result");
console.timeEnd("query");

Groups

console.group("Auth");
console.log("token", token);
console.group("User");
console.log({ id, name });
console.groupEnd();
console.groupEnd();

console.groupCollapsed is supported but rendered identically to group in a terminal.

Tables

console.table([
  { name: "Alice", age: 30 },
  { name: "Bob", age: 25 },
]);

console.table([
  { name: "Alice", age: 30, role: "admin" },
  { name: "Bob", age: 25, role: "user" },
], ["name", "role"]); // restrict columns

Other Methods

console.dir(obj); // tree-style object inspection
console.trace(); // logs a stack trace
console.clear(); // clear the terminal (best effort)

Patterns

Custom logger wrapper

function log(
  level: "info" | "warn" | "error",
  scope: string,
  msg: string,
  data?: unknown,
) {
  const ts = new Date().toISOString();
  const target = console[level];
  if (data === undefined) target(`[${ts}] [${scope}] ${msg}`);
  else target(`[${ts}] [${scope}] ${msg}`, data);
}

log("info", "boot", "starting", { port: 3000 });
log("error", "db", "connection failed");

Conditional debug logging

const DEBUG = Andromeda.env.get("DEBUG") === "1";
const debug = DEBUG ? console.debug.bind(console) : () => {};
debug("verbose info", details);