CachedTracer

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

Instance methods

beginTrace

Begins recording an operation trace.

public beginTrace(context: IContext, component: string, operation: string): TraceTiming

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

public clear(): void

configure

Configures component by passing configuration parameters.

public configure(config: ConfigParams): void

• config: ConfigParams - configuration parameters to be set.

dump

Dumps (writes) the currently cached log messages.

public dump(): void

failure

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

public failure(context: IContext, component: string, operation: string, error: Error, duration: number): void

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

setReferences

Sets references to dependent components.

public setReferences(references: IReferences): void

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

trace

Records an operation trace with its name and duration.

public trace(context: IContext, component: string, operation: string, duration: number): void

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

update

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

protected update(): void

write

Writes a log message to the logger destination.

protected write(context: IContext, component: string, operation: string, error: Error, duration: number): void

• correlationId: string - (optional) transaction id to trace execution through call chain.
• component: string - name of the called component
• operation: string - name of the executed operation.
• error: Error - an error object associated with this trace.
• duration: number - execution duration in milliseconds.

Abstract methods

save

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

protected abstract save(messages: OperationTrace[], callback: (err: any) => void): void

• messages: OperationTrace[] - a list with log messages
• callback: (err: any) => void - callback function that receives error or null for success.

See also

• ITracer

• OperationTrace