Incendium

Incendium is a small set of useful cross-platform .NET standard 2.1 libraries for .NET developers.

Package	Description	Nuget
Incendium.Result	Contains Error, Result<T> and NullableResult<T> types which allows to return a success value or an error
Incendium.RetryPolicy	Contains RetryHttpClientHandler to easily retry HTTP requests in case of errors, as well as RateGate to control rate limiting

Getting started

Installation

PM> Install-Package Incendium.Result

PM> Install-Package Incendium.RetryPolicy

Result<T> and NullableResult<T>

More docs. If you need to return either a not-null value or an error from a method, you can use the Result<T> type:

public async Result<string> GetStringAsync() {
    // ...
    if (condition1) {
        return "Test string result";
    } else {
        return new Error(code: 123, message: "Test error");
    }

    try {
        // ...
    } catch (Exception e) {
        return new Error(code: 321, message: "Test error", exception: e);
    }
}

Then processing the result might look like this:

var (str, error) = await GetStringAsync();

if (error != null) {
    log.LogError(
        error.Exception(),
        "Error with code {@code} and message {@message}",
        error.Code,
        error.Message);
}

RetryHttpClientHandler

More docs. Сan be used as a handler for HttpClient and allows you to easily set up repeated requests with constant or exponential delays in the following cases:

• HttpNetworkException
• Server errors (5xx)
• Request timeout error (408)
• Too many requests (429)

and also allows you to configure rate limiting using RateGate:

var innerHttpClientHandler = new HttpClientHandler(); // can be easily mocked
var retryHttpClientHandler = new RetryHttpClientHandler(innerHttpClientHandler)
{
    RetryCount = 5, // sets 5 retry attempts
    RetryOnHttpRequestException = true, // sets the retry flag in case of an HttpRequestException
    FirstRetryDelay = TimeSpan.FromMilliseconds(100), // sets the median starting delay between requests
    RateGate = new RateGate(
        occurrences: 10, // sets rate limit to 10 request per 60 seconds
        timeUnit: TimeSpan.FromSeconds(60))
}
var httpClient = new HttpClient(retryHttpClientHandler);