DmitryLegostaev.Polly.ConditionalWait 2.0.0

DmitryLegostaev.Polly.ConditionalWait

A small class library to provide Conditional Wait functionality using Polly v7 library.

Usage

Obtaining ConditionalWait object instance

Explicitly create ConditionalWait object

var conditionalWait = new ConditionalWait();

or use a DI to obtain ConditionalWait object.

(optional) Configuration of default Timeout and BackOffDelay

You can configure default timeout and backoffdelay for ConditionalWait object through its constructor. Defaults are 30s/300ms

var conditionalWait = new ConditionalWait(TimeSpan.FromSeconds(10), TimeSpan.FromSeconds(3));

or set environment variables

Environment.SetEnvironmentVariable("ConditionalWait__defaultTimeout", TimeSpan.FromSeconds(10).ToString());
Environment.SetEnvironmentVariable("ConditionalWait__defaultBackOffDelay", TimeSpan.FromSeconds(3).ToString());

Configuration priority is: Constructor parameters → Environment variables → Pre-defined defaults (30s/300ms)

Actual usage

Each method require Func to execute within its body. WaitForPredicateAndGetResult requires a predicate to be passed as argument in addition to Func.

// Wait for true to be returned from Func execution.
conditionalWait.WaitForTrue(() => 2 + 2 == 4);

// Wait for not null object to be returned from Func execution. Returns Func execution result to the calling method.
var equationResult = conditionalWait.WaitForAndGetResult(() => 2 + 2);

// Executing Func, obtaining its result, passing the result to the predicate, waiting for true to be returned from predicate. Returns Func execution result to the calling method.
var equationResult = conditionalWait.WaitForPredicateAndGetResult(() => 2 + 2, eq => eq == 4);

Each method could consume IConditionalWaitConfiguration object or Timeout/BackOffDelay. If 2nd option is chosen but Timeout or BackOffDelay is missing, then it will be obtained from ConditionalWait defaults defined during ConditionalWait object instantiation.

conditionalWait.WaitForTrue(() => 2 + 2 == 4,
    new ConditionalWaitConfiguration(TimeSpan.FromSeconds(10), TimeSpan.FromSeconds(3)));

conditionalWait.WaitForTrue(() => 2 + 2 == 4,
    TimeSpan.FromSeconds(10), TimeSpan.FromSeconds(3));
    
conditionalWait.WaitForTrue(() => 2 + 2 == 4,
    timeout: TimeSpan.FromSeconds(10));
    
conditionalWait.WaitForTrue(() => 2 + 2 == 4,
    backoffDelay: TimeSpan.FromSeconds(3));

Also ConditionalWait methods consume some optional arguments:

ConditionalWaitConfiguration

To create ConditionalWaitConfiguration object you should pass TimeSpan Timeout and TimeSpan BackOffDelay to its constructor. Also you can set Factor and BackoffType to customize main ConditionalWait behaviour based on WaitAndRetry policy.

ConditionalWaitConfiguration could be mapped from .NET Configuration by Microsoft.Extensions.Configuration.ConfigurationBinder.

To understand more about ConditionalWaitConfiguration capabilities visit https://github.com/Polly-Contrib/Polly.Contrib.WaitAndRetry