mirror of https://git.lenooby09.tech/LeNooby09/social-app.git
lenooby09.tech
1# Logger
2
3Simple logger for Bluesky. Supports log levels, debug contexts, and separate
4transports for production, dev, and test mode.
5
6## At a Glance
7
8```typescript
9import { logger } from '#/logger'
10
11logger.debug(message[, metadata, debugContext])
12logger.info(message[, metadata])
13logger.log(message[, metadata])
14logger.warn(message[, metadata])
15logger.error(error[, metadata])
16```
17
18#### Modes
19
20The "modes" referred to here are inferred from the values exported from `#/env`.
21Basically, the booleans `IS_DEV`, `IS_TEST`, and `IS_PROD`.
22
23#### Log Levels
24
25Log levels are used to filter which logs are either printed to the console
26and/or sent to Sentry and other reporting services. To configure, set the
27`EXPO_PUBLIC_LOG_LEVEL` environment variable in `.env` to one of `debug`,
28`info`, `log`, `warn`, or `error`.
29
30This variable should be `info` in production, and `debug` in dev. If it gets too
31noisy in dev, simply set it to a higher level, such as `warn`.
32
33## Usage
34
35```typescript
36import { logger } from '#/logger';
37```
38
39### `logger.error`
40
41The `error` level is for... well, errors. These are sent to Sentry in production mode.
42
43`error`, along with all log levels, supports an additional parameter, `metadata: Record<string, unknown>`. Use this to provide values to the [Sentry
44breadcrumb](https://docs.sentry.io/platforms/react-native/enriching-events/breadcrumbs/#manual-breadcrumbs).
45
46```typescript
47try {
48 // some async code
49} catch (e) {
50 logger.error(e, { ...metadata });
51}
52```
53
54### `logger.warn`
55
56Warnings will be sent to Sentry as a separate Issue with level `warning`, as
57well as as breadcrumbs, with a severity level of `warning`
58
59### `logger.log`
60
61Logs with level `log` will be sent to Sentry as a separate Issue with level `log`, as
62well as as breadcrumbs, with a severity level of `default`.
63
64### `logger.info`
65
66The `info` level should be used for information that would be helpful in a
67tracing context, like Sentry. In production mode, `info` logs are sent
68to Sentry as breadcrumbs, which decorate log levels above `info` such as `log`,
69`warn`, and `error`.
70
71### `logger.debug`
72
73Debug level is really only intended for local development. Use this instead of
74`console.log`.
75
76```typescript
77logger.debug(message, { ...metadata });
78```
79
80Inspired by [debug](https://www.npmjs.com/package/debug), when writing debug
81logs, you can optionally pass a _context_, which can be then filtered when in
82debug mode.
83
84This value should be related to the feature, component, or screen
85the code is running within, and **it should be defined in `#/logger/debugContext`**.
86This way we know if a relevant context already exists, and we can trace all
87active contexts in use in our app. This const enum is conveniently available on
88the `logger` at `logger.DebugContext`.
89
90For example, a debug log like this:
91
92```typescript
93logger.debug(message, {}, logger.DebugContext.composer);
94```
95
96Would be logged to the console in dev mode if `EXPO_PUBLIC_LOG_LEVEL=debug`, _or_ if you
97pass a separate environment variable `LOG_DEBUG=composer`. This variable supports
98multiple contexts using commas like `LOG_DEBUG=composer,profile`, and _automatically
99sets the log level to `debug`, regardless of `EXPO_PUBLIC_LOG_LEVEL`._