Class AbstractAuthenticationService<TClient>

Namespace

Visus.AddressValidation.Services

Assembly

Visus.AddressValidation.dll

Abstract base class for an authentication service that obtains and caches access tokens via an IAuthenticationClient implementation.

public abstract class AbstractAuthenticationService<TClient> where TClient : IAuthenticationClient

Type Parameters

TClient

The type of IAuthenticationClient used to request access tokens.

Inheritance

object

AbstractAuthenticationService<TClient>

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

AbstractAuthenticationService(TClient, HybridCache)

Initializes a new instance of AbstractAuthenticationService<TClient>.

protected AbstractAuthenticationService(TClient authenticationClient, HybridCache cache)

Parameters

authenticationClient TClient

The IAuthenticationClient used to request access tokens.

cache HybridCache

The HybridCache used to cache access tokens.

Exceptions

ArgumentNullException

Thrown when authenticationClient or cache is null.

Fields

CacheKeyTag

Prefix applied to all cache keys produced by this service to namespace them within the shared cache.

protected const string CacheKeyTag = "vs-ave-auth:"

Field Value

string

Methods

GenerateCacheKey()

Generates a unique cache key for caching retrieved access tokens.

protected abstract string GenerateCacheKey()

Returns

string

A non-null, non-empty string containing only A-Z, a-z, 0-9, underscores, hyphens, and colons.

Exceptions

InvalidOperationException

Thrown when the required credentials needed to construct the key are absent or invalid, or when the returned key contains characters outside the allowed set.

GetAccessTokenAsync(CancellationToken)

Retrieves an access token using token-based authentication.

public Task<string?> GetAccessTokenAsync(CancellationToken cancellationToken = default)

Parameters

cancellationToken CancellationToken

A cancellation token that can be used to cancel the work.

Returns

Task<string>

The current access token returned by the authentication service, or null if the authentication service did not return a valid token.

Remarks

The access token is cached using HybridCache. When no cached entry exists, a new token is fetched via RequestClientCredentialsTokenAsync(CancellationToken) and stored in the cache with an expiration of ExpiresIn - 60 seconds to provide a safety buffer before the token actually expires.

Subsequent calls return the cached token until it expires, at which point a new token is fetched and cached. If the authentication service returns an invalid or empty token, the cache entry is removed and null is returned.