CachedTracer

Abstract tracer that caches recorded traces in memory and periodically dumps them.

Implements: ITracer, IReconfigurable, IReferenceable

Description

The CachedTracer class allows you to create a tracer that caches the recorded traces in memory and periodically dumps them.

Important points

  • Child classes implement saving cached traces to their specified destinations.

Configuration parameters

  • source: source (context) name
  • 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)

References

  • *:context-info:*:*:1.0 - (optional) ContextInfo to detect the context id and specify counters source

Fields

_source

Source (context) name

_source: String?

_cache

List of traces

_cache: List<OperationTrace>

_updated

Boolean variable that indicates whether there has been an update or not.

_updated: bool

_lastDumpTime

Time of the last dump

_lastDumpTime: int

_maxCacheSize

Maximum number of messages stored in this cache (default: 100)

_maxCacheSize = 100

_interval

Interval in milliseconds to save log messages (default: 10 seconds)

_interval = 10000

Instance methods

beginTrace

Begins recording an operation trace.

@override

TraceTiming beginTrace(IContext? context, String component, String operation)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • component: String - name of a called component
  • operation: String - name of the executed operation.
  • return: TraceTiming - a trace timing object.

clear

Clears (removes) all cached log messages.

void clear()

configure

Configures component by passing configuration parameters.

@override

void configure(ConfigParams config)

  • config: ConfigParams - configuration parameters to be set.

dump

Dumps (writes) the currently cached log messages.

void dump()

failure

Records an operation failure with its name, duration and error.

@override

void failure(IContext? context, String component, String operation, Exception error, int duration)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • component: String - name of the called component
  • operation: String - name of the executed operation.
  • error: Exception - an error object associated with this trace.
  • duration: int - execution duration in milliseconds.

setReferences

Sets references to dependent components.

@override

void setReferences(IReferences references)

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

trace

Records an operation trace with its name and duration.

@override

void trace(IContext? context, String component, String operation, int duration)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • component: String - name of the called component
  • operation: String - name of the executed operation.
  • duration: int - execution duration in milliseconds.

update

Sets trace cache as updated and dumps it when timeout expires.

void update()

write

Writes a log message to the logger destination.

void write(IContext? context, String? component, String? operation, Exception? error, int duration)

  • context: IContext - (optional) a context to trace execution through a call chain.
  • component: String? - name of the called component
  • operation: String? - name of the executed operation.
  • error: Exception? - an error object associated with this trace.
  • duration: int - execution duration in milliseconds.

save

Saves log messages from the cache. Throws error if not done.

void save(List<OperationTrace> messages, void Function(Exception? err) callback)

  • messages: List<OperationTrace> - a list with log messages
  • callback: void Function(Exception? err) - callback function that receives error or null for success.

See also