EastFive.Core 1.0.0-preview-0035

EastFive

Functional-programming libraries for .NET: a composable core (TResult continuations, IEnumerableAsync, attribute-interface IoC), an attribute-routed REST API framework, Azure persistence/auth/integration bindings, spreadsheet tooling, and Roslyn source generators.

All packages ship one shared version, MIT-licensed, with embedded PDBs and embedded source (step-into debugging works without symbol servers).

This mono-repo supersedes the former EastFive.Core, EastFive.Api, EastFive.Azure, EastFive.Sheets, and EastFive.Generators repositories; their histories are preserved under src/.

Build

dotnet build EastFive.sln
dotnet test EastFive.sln   # Azure tests require a running Azurite

Configuration and secrets

EastFive reads configuration from two stores and never mixes them.

Typed configuration is the only way to read a secret

Every setting a feature needs is a property of an IProvideConfiguration type. Values are declared with their key; secrets are declared without one:

[ConfigurationType("Telnyx")]
public sealed class TelnyxConfiguration : IProvideConfiguration
{
    [ConfigurationMember("Telnyx.Account", Account = true, Label = "Account")]
    public string Account { get; set; }

    [ConfigurationMember(Kind = ConfigurationMemberKind.Secret, Label = "API key")]
    public Secret ApiKey { get; set; }
}

var outcome = await ConfigurationLoader.LoadAsync<TelnyxConfiguration, TResult>(
    onConfigured, onMissing, onInvalid, onSourceFailure);

ConfigurationString and friends are for values only; a guard test in each framework test project fails if one reads a secret. Secret has no public value: Reveal() it at the point of use, and never into a log, an exception or a response.

Generated secret names

Secret names are never hand-written. {Type}-{Account}-{Property} for a type with an account member, {Type}-{Property} otherwise: Type is the [ConfigurationType] name, Account the account member's value, Property the secret member's property name. Names are valid Azure Key Vault secret names ([A-Za-z0-9-]); an account id that would not be is refused, never mapped — unless the account member declares an exact, type-specific translation with an attribute implementing IProvideSecretAccountSegment (Google client ids drop their constant .apps.googleusercontent.com domain). The translated segment is still validated. Types that share a [ConfigurationType] and an account share one secret — every StorageAccountConfiguration on account prod reads AzureStorage-prod-ConnectionString.

ConfigurationCatalog.For(assemblies) lists every configuration type with its members, metadata (label, description, location, scope, field kind) and generated names; editors and doctors render from it. IProvideConfigurationLookup and ITestConfiguration are the attribute-interface hooks for choices and live checks of a ConfigurationDraft.

Where secrets come from

A host initializes SecretStore.Current next to ConfigurationExtensions.Initialize, typically:

SecretStore.Initialize(new CompositeSecretStore(
    new ConfigurationSecretOverrides(ConfigurationLoader.ReadAmbient),   // Secrets:{name}
    KeyVaultSecretStore.From(vaults)));                                 // the environment's vaults, in order

1. Local override: Secrets:{generated-name} in the values store — written only in appsettings.local*.json or the environment (Secrets__AzureStorage-dev-ConnectionString).
2. The environment's vaults, in order: one SecretClient per vault, managed identity when deployed, a service principal (KeyVaultAccess) locally. 404 falls through to the next vault; any other error is a failure, so an outage is never read as "unset". Found and missing answers are cached per name for 30 minutes.

Until a host initializes it, SecretStore.Current is the local overrides alone.

Synchronous readers: load at startup

Loading a type with secret members is asynchronous. Code that cannot await — attributes, the storage driver factory, token signing — reads a configuration the host loaded once at startup:

await StartupConfiguration.LoadAsync(new[] { typeof(EastFive.Azure.AppSettings).Assembly, /* … */ });
StartupConfiguration.Get<TokenSigningConfiguration, TResult>(onLoaded, onUnavailable);   // never loads, never blocks

A type the host did not load answers ConfigIssueCategory.NotLoaded. RefreshEveryAsync re-reads the loaded types on an interval to pick up rotated secrets.

Storage

A store is named by its StorageAccountConfiguration type (StorageAccount.Tables, StorageAccount.Of<T>()); its account comes from <Store>.Account and its credential from AzureStorage-{account}-ConnectionString. The emulator account devstoreaccount1 is fabricated from Azure.Storage.Emulator.Port and never read from the secret store.