Logger.Backends.Logfmt.Encoder (LoggerLogfmt v1.0.1)

Encodes key-value pairs in logfmt format.

This module handles the encoding of various Elixir data types into logfmt-compliant key-value pairs, with proper quoting and escaping.

Supported Types

Integers and floats
Booleans
Atoms
Strings (with automatic quoting when needed)
Timestamps (multiple formats supported)
DateTime and NaiveDateTime structs
Maps (encoded with dot notation for nested keys)
Any type (fallback to inspect/2)

Timestamp Formats

:elixir - "2024-01-15 10:30:45.123"
:iso8601 - "2024-01-15T10:30:45.123Z"
:epoch_time - Unix timestamp (seconds since epoch)

Time Unit Detection for epoch_time

When using :epoch_time format with DateTime or NaiveDateTime values, the time unit is automatically detected from the key suffix:

*_ms - milliseconds (e.g., timestamp_ms=1732579200000)
*_us - microseconds (e.g., created_at_us=1732579200000000)
*_ns - nanoseconds (e.g., event_time_ns=1732579200000000000)
No suffix - seconds (e.g., timestamp=1732579200)

Examples

iex> Logger.Backends.Logfmt.Encoder.encode("level", "info")
"level=info"

iex> Logger.Backends.Logfmt.Encoder.encode("count", 42)
"count=42"

iex> Logger.Backends.Logfmt.Encoder.encode("message", "Hello World")
"message=\"Hello World\""

Summary

Functions

encode(key, val, opts \\ [])

Encodes a key-value pair in logfmt format.

Functions

encode(key, val, opts \\ [])

Encodes a key-value pair in logfmt format.

Parameters

key - The key (will be converted to string)
val - The value to encode
opts - Optional keyword list with encoding options:
- :delimiter - Key-value delimiter (default: =)
- :timestamp_format - Format for timestamp values (default: :elixir)
- :prefix - Prefix for nested keys (default: "")

Returns

A string or iolist representing the encoded key-value pair.

Examples

iex> Logger.Backends.Logfmt.Encoder.encode("name", "John")
"name=John"

iex> Logger.Backends.Logfmt.Encoder.encode("count", 42)
"count=42"