ElasticSearchLogger

Extends: CachedLogger

Implements: IReferenceable, IOpenable

Description

The ElasticSearchLogger class allows you to create loggers that dump execution logs to an ElasticSearch service.

Important points

• Elasticsearch is a popular search index. It is often used to store and index execution logs by itself or as a part of ELK (ElasticSearch - Logstash - Kibana) stack.
• Authentication is not supported in this version.

Configuration parameters

• level: maximum log level to capture
• source: source (context) name

connection(s):

• discovery_key: (optional) key to retrieve the connection from IDiscovery
• protocol: connection protocol: http or https
• host: host name or IP address
• port: port number
• uri: resource URI or connection string with all parameters in it

options:

• interval: interval in milliseconds to save log messages (default: 10 seconds)
• max_cache_size: maximum number of messages stored in this cache (default: 100)
• index: ElasticSearch index name (default: “log”)
• date_format: date format used to create the index name. Eg. log-YYYYMMDD (default: “YYYYMMDD”).
• daily: True to create a new index every day by adding a date suffix to the index name (default: False)
• reconnect: reconnect timeout in milliseconds (default: 60 sec)
• timeout: invocation timeout in milliseconds (default: 30 sec)
• max_retries: maximum number of retries (default: 3)
• index_message: True to enable indexing for message object (default: False)
• include_type_name: will create using a “typed” index compatible with ElasticSearch 6.x (default: false)

References

• *:discovery:*:*:1.0 - (optional) IDiscovery services
• *:context-info:*:*:1.0 - (optional) ContextInfo to detect the context id and specify the counter’s source.

Constructors

Creates a new instance of the logger.

ElasticSearchLogger()

Instance methods

close

Closes the component and frees used resources.

@override

Future close(IContext? Context)

• context: IContext - (optional) a context to trace execution through a call chain.

configure

Closes the component and frees used resources.

@override

void configure(ConfigParams config)

• config: ConfigParams - configuration parameters to be set.

getLogItem

Converts elasticsearch object to 6.x or 7.x version by include_type_name parameter.

Map<String, dynamic> getLogItem()

• returns: Map<String, dynamic> - map in elasticsearch object format

isOpen

Checks if the component is open.

@override

bool isOpen()

• returns: bool - true if the component is open and false otherwise.

open

Opens the component.

@override

Future open(IContext? context)

• context: IContext - (optional) a context to trace execution through a call chain.

save

Saves log messages from the cache.

@override

Future save(List<LogMessage> messages)

• messages: List<LogMessage> - list with log messages

setReferences

Sets references to dependent components.

@override

void setReferences(IReferences references)

• messages: IReferences - references to locate the component dependencies.

Examples

var logger = ElasticSearchLogger();
logger.configure(ConfigParams.fromTuples([
    'connection.protocol', 'http',
    'connection.host', 'localhost',
    'connection.port', 9200
]));
await logger.open('123')
    ...
logger.error('123', ex, 'Error occured: %s', ex.message);
logger.debug('123', 'Everything is OK.');