com.comoyo.logging.context.json

Class JsonEventFormatter

java.lang.Object

java.util.logging.Formatter

com.comoyo.logging.context.json.JsonEventFormatter

public class JsonEventFormatter
extends Formatter

LoggingContext-aware log formatter for producing logstash-ready JSON. This is just a formatter, shipping the product off to logstash is left as an exercise for the reader. One recommended option is log with a regular FileHandler and asynchronously transport those to logstash, an alternative is to send the events directly into a Redis list with a custom LogHandler. JSON structure and names based on JSONEventLayoutV1.java from log4j-jsonevent-layout.

Author:

anders

Field Summary

Fields

Modifier and Type	Field and Description
(package private) static String	ISO8601_DATE_FORMAT
static String	JSON_KEY_CAUSE
static String	JSON_KEY_CONTEXT
static String	JSON_KEY_EXCEPTION
static String	JSON_KEY_EXCEPTION_CLASS
static String	JSON_KEY_EXCEPTION_MESSAGE
static String	JSON_KEY_EXCEPTION_STACKTRACE
static String	JSON_KEY_LEVEL
static String	JSON_KEY_LOGGER_NAME
static String	JSON_KEY_MESSAGE
static String	JSON_KEY_SOURCE
static String	JSON_KEY_SOURCE_CLASS
static String	JSON_KEY_SOURCE_HOST
static String	JSON_KEY_SOURCE_METHOD
static String	JSON_KEY_SUPPRESSED
static String	JSON_KEY_THREAD_ID
static String	JSON_KEY_THREAD_NAME
static String	JSON_KEY_TIMESTAMP
static String	JSON_KEY_VERSION
(package private) static int	LOGSTASH_JSON_VERSION
(package private) static String	PRETTY_PROPERTY
(package private) static String	PROPERTY_PREFIX
(package private) static String	SOURCE_PROPERTY
(package private) static String	SOURCEHOST_PROPERTY
(package private) static String	TAG_PROPERTY
(package private) static String	TAG_SEPARATOR_REGEX

Constructor Summary

Constructors

Constructor and Description
JsonEventFormatter() Default constructor for use by java.util.logging - retrieves configuration from logging properties:
JsonEventFormatter(String hostName, String source, List<String> tags, JsonGeneratorFactory jsonFactory) Construct a JSON log event formatter with explicit configuration, without looking at the java.util.logging properties.

Method Summary

Methods

Modifier and Type	Method and Description
String	format(LogRecord record)
(package private) String	getHostName()
(package private) String	getSourceName()
(package private) List<String>	getTags()

Methods inherited from class java.util.logging.Formatter

formatMessage, getHead, getTail

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JSON_KEY_VERSION

public static final String JSON_KEY_VERSION

See Also:

Constant Field Values

JSON_KEY_TIMESTAMP

public static final String JSON_KEY_TIMESTAMP

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Constant Field Values

JSON_KEY_LEVEL

public static final String JSON_KEY_LEVEL

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Constant Field Values

JSON_KEY_MESSAGE

public static final String JSON_KEY_MESSAGE

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Constant Field Values

JSON_KEY_SOURCE

public static final String JSON_KEY_SOURCE

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Constant Field Values

JSON_KEY_SOURCE_HOST

public static final String JSON_KEY_SOURCE_HOST

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Constant Field Values

JSON_KEY_LOGGER_NAME

public static final String JSON_KEY_LOGGER_NAME

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Constant Field Values

JSON_KEY_SOURCE_METHOD

public static final String JSON_KEY_SOURCE_METHOD

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Constant Field Values

JSON_KEY_SOURCE_CLASS

public static final String JSON_KEY_SOURCE_CLASS

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Constant Field Values

JSON_KEY_CONTEXT

public static final String JSON_KEY_CONTEXT

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Constant Field Values

JSON_KEY_EXCEPTION

public static final String JSON_KEY_EXCEPTION

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Constant Field Values

JSON_KEY_CAUSE

public static final String JSON_KEY_CAUSE

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Constant Field Values

JSON_KEY_SUPPRESSED

public static final String JSON_KEY_SUPPRESSED

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Constant Field Values

JSON_KEY_EXCEPTION_CLASS

public static final String JSON_KEY_EXCEPTION_CLASS

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Constant Field Values

JSON_KEY_EXCEPTION_MESSAGE

public static final String JSON_KEY_EXCEPTION_MESSAGE

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Constant Field Values

JSON_KEY_EXCEPTION_STACKTRACE

public static final String JSON_KEY_EXCEPTION_STACKTRACE

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Constant Field Values

JSON_KEY_THREAD_ID

public static final String JSON_KEY_THREAD_ID

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Constant Field Values

JSON_KEY_THREAD_NAME

public static final String JSON_KEY_THREAD_NAME

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Constant Field Values

LOGSTASH_JSON_VERSION

static final int LOGSTASH_JSON_VERSION

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Constant Field Values

ISO8601_DATE_FORMAT

static final String ISO8601_DATE_FORMAT

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Constant Field Values

PROPERTY_PREFIX

static final String PROPERTY_PREFIX

TAG_PROPERTY

static final String TAG_PROPERTY

See Also:

Constant Field Values

PRETTY_PROPERTY

static final String PRETTY_PROPERTY

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Constant Field Values

SOURCE_PROPERTY

static final String SOURCE_PROPERTY

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Constant Field Values

SOURCEHOST_PROPERTY

static final String SOURCEHOST_PROPERTY

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Constant Field Values

TAG_SEPARATOR_REGEX

static final String TAG_SEPARATOR_REGEX

See Also:

Constant Field Values

Constructor Detail

JsonEventFormatter

public JsonEventFormatter()

Default constructor for use by java.util.logging - retrieves configuration from logging properties:

com.comoyo.logging.context.json.JsonEventFormatter.source_host

: explicit configuration of host name in log entries - default auto-determined.

com.comoyo.logging.context.json.JsonEventFormatter.source

: Log source, i.e. application name

com.comoyo.logging.context.json.JsonEventFormatter.tags

: Comma/space separated list of strings to tag log entries with, i.e. runtime environment

com.comoyo.logging.context.json.JsonEventFormatter.pretty

: If "true" or "yes", output JSON formatted with indentation and line breaks for human consumption. Possibly useful for debugging, not recommended for machine consumption.

JsonEventFormatter

public JsonEventFormatter(String hostName,
                  String source,
                  List<String> tags,
                  JsonGeneratorFactory jsonFactory)

Construct a JSON log event formatter with explicit configuration, without looking at the java.util.logging properties.

Parameters:

hostName - Host name to use in log entries.

source - Log source - i.e. application name.

tags - Strings to tag log entries with, i.e. runtime environment: "production", "test"

prettyJson - If true; output more human-readable JSON. Not recommended for machine consumption, but perhaps more convenient when debugging.

jsonFactory - - a JsonFactory configured to your liking, i.e.

 final HashMap jsonConfig = new HashMap<>(1);
 jsonConfig.put(JsonGenerator.PRETTY_PRINTING, "true");
 final JsonFactory jsonFactory = Json.createGeneratorFactory(jsonConfig);
 

to get pretty-printed JSON with whitespace and indentation.

Method Detail

format

public String format(LogRecord record)

Specified by:

format in class Formatter

Parameters:

record - A Java log record.

Returns:

A string containing a logstash-style JSON log event.

getHostName

String getHostName()

getSourceName

String getSourceName()

getTags

List<String> getTags()