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 used to detect the context id and specify a counter’s source

Interfaces

ICachedTraceSaver

Abstract tracer that caches recorded traces in memory and periodically dumps them Methods Save Save method for counters.

Save(ctx context.Context, operations []OperationTrace) error

Constructors

InheritCachedTracer

InheritCachedTracer(saver ICachedTraceSaver) *CachedTracer

  • saver: ICachedTraceSaver - inherited tracer

Fields

Cache

List of traces

Cache: []*OperationTrace

source

Source (context) name

source: string

updated

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

updated: bool

lastDumpTime

Time of the last dump

lastDumpTime: time.Time

maxCacheSize

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

maxCacheSize: int

interval

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

interval: int64

Methods

BeginTrace

Begins recording an operation trace.

(c *CachedTracer) BeginTrace(context IContext, component string, operation string) *TraceTiming

  • 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 - trace timing object.

Clear

Clears (removes) all cached log messages.

(c *CachedTracer) Clear(ctx context.Context)

  • ctx: context.Context - operation context.

Configure

Configures component by passing configuration parameters.

(c *CachedTracer) Configure(ctx context.Context, config *cconf.ConfigParams)

  • ctx: context.Context - operation context.
  • config: *cconf.ConfigParams - configuration parameters to be set.

Dump

Dumps (writes) the currently cached log messages.

(c *CachedTracer) Dump(ctx context.Context)

  • ctx: context.Context - operation context.

Failure

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

(c *CachedTracer) Failure(ctx context.Context, context IContext, component string, operation string, err error, duration int64)

  • ctx: context.Context - operation context.
  • 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.
  • err: error - error object associated with this trace.
  • duration: int64 - execution duration in milliseconds.

SetReferences

Sets references to dependent components.

(c *CachedTracer) SetReferences(ctx context.Context, references cref.IReferences)

  • ctx: context.Context - operation context.
  • references: cref.IReferences - references to locate the component dependencies.

Trace

Records an operation trace with its name and duration.

(c *CachedTracer) Trace(ctx context.Context, context IContext, component string, operation string, duration int64)

  • ctx: context.Context - operation context.
  • context: IContext - (optional) transaction id to trace execution through a call chain.
  • component: string - name of the called component
  • operation: string - name of the executed operation.
  • duration: int64 - execution duration in milliseconds.

Update

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

(c *CachedTracer) update(ctx context.Context)

  • ctx: context.Context - operation context.

Write

Writes a log message to the logger destination.

(c *CachedTracer) Write(ctx context.Context, context IContext, component string, operation string, err error, duration int64)

  • ctx: context.Context - operation context.
  • context: IContext - (optional) transaction id used to trace execution through the call chain.
  • component: string - name of the called component
  • operation: string - name of the executed operation.
  • err: error - error object associated with this trace.
  • duration: int64 - execution duration in milliseconds.

Save

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

Save(ctx context.Context, operations []*OperationTrace) error

  • ctx: context.Context - operation context.
  • operations: []*OperationTrace - list with log messages
  • returns: error - save error.

See also