SAIF.Application.Services.AudioVideo architecture¶

SAIF.Application.Services.AudioVideo is a single-assembly Framework4 component library that orchestrates the import, invalidation, and cancellation of call recordings from the third-party CallRex call-recording appliance into SAIF, backed by an NHibernate-mapped persistence layer and a set of WCF client proxies that isolate all vendor-system interaction behind a single adapter boundary.

Responsibilities¶

Orchestrate the end-to-end call-recording import workflow (AudioVideoService.ImportRecording): validate the request, create or reuse a Recording database row, back up and MD5-verify the source media file, transcode it to .wma via MediaToolkit/ffmpeg.exe, verify the destination file, delete the source recording from CallRex, and mark import status complete.
Track per-recording import status (ImportStatusManager/IImportStatusManager) as a distinct concern from the Recording entity itself — only AudioImportStatus state passes through the status manager.
Provide a vendor-integration adapter (CallRecordingSystem/IRecordingSystem) that hides two WCF proxy classes (CallRexServiceProxy, CallRexStateServiceProxy) behind a single interface for on-demand recording operations and a real-time duplex agent-state feed.
Expose contracts (DTOs, enums, service interfaces) in SAIF.Core.Contracts.AudioVideo/SAIF.Core.Services that are free of persistence or transport concerns.
Support a "degraded mode" construction path (AudioVideoService(IUnitOfWork uow)) that limits a consumer to the HasMedia(long) query only, for callers that need existence-checking without the full service graph*.

Component boundaries¶

Contracts layer (SAIF.Core.Contracts.AudioVideo, SAIF.Core.Services) — pure DTOs, enums, and interfaces (IAudioVideoService, IRecordingSystem, IImportStatusManager); no dependency on persistence or transport.
Persistence layer (SAIF.Data.Model.AudioVideo, SAIF.Data.NHibernate.Mappings.AudioVideo) — NHibernate entities Recording and AudioImportStatus and their ClassMap<T> mappings (RecordingMap, AudioImportStatusMap), consumed through IUnitOfWork/IRepository<T> supplied by SAIF.Framework.Data.NHibernate.
Service/orchestration layer (SAIF.Services.Utilities.AudioVideo) — AudioVideoService is the single public entry point (IAudioVideoService) coordinating validation, persistence, file handling, and vendor deletion; AudioVideoValidator enforces request validation rules; ImportStatusManager owns AudioImportStatus state; CallRecordingExtensions computes description/discoverability values.
Vendor adapter layer (SAIF.Services.ClientProxies.ThirdParty) — CallRecordingSystem delegates to CallRexServiceProxy (on-demand recording/user-list/recording-metadata SOAP operations) and CallRexStateServiceProxy (duplex real-time agent-state feed via AgentStateCallback). No other class in the library talks to CallRex directly.
Framework dependencies — SAIF.Framework.Core supplies IEnvironmentService, ILogService, IUnitOfWork, IRepository<T>; SAIF.Framework.Data.NHibernate supplies the concrete NHibernate unit-of-work/repository stack; SAIF.Framework.Common supplies EntityBase<T>, Enforce, SaifValidationException, IConsoleLogService, and extension methods (GetMD5Hash, GetErrorLogFormattedException).

Interaction model¶

An external caller (outside this library) invokes IAudioVideoService.ImportRecording, GetRecordingInfo, InvalidateRecording, CancelImport, or HasMedia on AudioVideoService.
AudioVideoService validates inbound ImportAudioRequest instances via AudioVideoValidator (FluentValidation) before performing any database, file-system, or vendor-system action.
Database access flows through constructor-injected IUnitOfWork/IRepository<Recording>/IRepository<AudioImportStatus> from SAIF.Framework.Data.NHibernate — there is no intermediate business-object/DAO abstraction beyond the repository itself*.
File-system side effects (backup copy, MD5 integrity check, ffmpeg transcode) are performed directly by AudioVideoService against a path resolved from IEnvironmentService.GetConfigSetting("AudioImportService.callRexMediaOutputPath").
Vendor-system interaction is always routed through IRecordingSystem/CallRecordingSystem, which in turn calls CallRexServiceProxy (synchronous SOAP operations, NTLM-authenticated BasicHttpsBinding, plus hardcoded SOAP-header credentials) or CallRexStateServiceProxy (duplex WSDualHttpBinding real-time feed with no transport/message security).
Real-time call-state updates arrive asynchronously through the AgentStateCallback duplex WCF callback contract and are re-raised to the library's own caller as the OnCallStateChanged event.
Import status is persisted/queried independently of the Recording row via ImportStatusManager, so AudioImportStatus and Recording lifecycles are not transactionally coupled to each other beyond the explicit rollback performed in the ImportRecording error-handling branch.

Architecture diagram¶

The following diagram shows the library's internal layering and its external system/dependency boundaries.

flowchart TD
    Caller["External caller<br>(outside this library)"] --> AVS["AudioVideoService<br>(IAudioVideoService)"]
    AVS --> Validator["AudioVideoValidator<br>(FluentValidation)"]
    AVS --> ISM["ImportStatusManager<br>(IImportStatusManager)"]
    AVS --> Repo["IUnitOfWork / IRepository&lt;T&gt;<br>(SAIF.Framework.Data.NHibernate)"]
    AVS --> FS["File system<br>(backup, MD5, ffmpeg transcode)"]
    AVS --> RS["CallRecordingSystem<br>(IRecordingSystem)"]
    ISM --> Repo
    RS --> Proxy1["CallRexServiceProxy<br>(SOAP, on-demand)"]
    RS --> Proxy2["CallRexStateServiceProxy<br>(duplex, real-time)"]
    Proxy1 --> CallRex["CallRex vendor system"]
    Proxy2 --> CallRex
    Repo --> Env["IEnvironmentService<br>(SAIF.Framework.Core)"]
    AVS --> Env
    Repo --> DB[("Oracle database<br>(RECORDING, audio_import_status)")]

Sequence diagram¶

The following diagram shows the primary ImportRecording request/response sequence.

sequenceDiagram
    participant Caller as External caller
    participant AVS as AudioVideoService
    participant Val as AudioVideoValidator
    participant Repo as IUnitOfWork/IRepository
    participant FS as File system / ffmpeg
    participant RS as CallRecordingSystem
    participant Vendor as CallRex vendor system
    Caller->>AVS: ImportRecording(ImportAudioRequest)
    AVS->>Val: Validate(request)
    Val-->>AVS: ValidationResult
    AVS->>Repo: Query/Add Recording
    Repo-->>AVS: Recording row
    AVS->>FS: Backup + MD5 verify + transcode
    FS-->>AVS: Success/failure
    AVS->>RS: DeleteRecording(callRecordingId)
    RS->>Vendor: DeleteRecording (SOAP)
    Vendor-->>RS: Result
    RS-->>AVS: Result
    AVS->>Repo: Mark AudioImportStatus completed
    AVS-->>Caller: RecordingInfo

Design constraints¶

The library targets .NET Framework 4.6.1 and is consumed as compiled NuGet packages (packages.config/<Reference>), not <ProjectReference>, for all internal SAIF dependencies — there is no compile-time project coupling to SAIF.Framework.Core, SAIF.Framework.Data.NHibernate, or SAIF.Framework.Common.
All vendor-system communication is constrained to the SAIF.Services.ClientProxies.ThirdParty namespace; no other layer is permitted to reference the generated WCF service-reference proxies directly.
The degraded-mode constructor (AudioVideoService(IUnitOfWork uow)) intentionally restricts the service surface to HasMedia(long) only — every other method throws NotImplementedException in that mode, reflecting a single external consumer's minimal dependency need*.
Database access is constrained to LINQ-to-NHibernate expressions against IRepository<TEntity>.Query(); no raw/inline SQL or stored-procedure calls exist in this library's own code.
The concrete IUnitOfWork implementation, its session strategy, and its Oracle/SQL Server configuration factory are resolved entirely inside SAIF.Framework.Data.NHibernate and/or the hosting application's DI composition root — this library only depends on the IUnitOfWork/IRepository<T> abstractions.**
Packaging status is uncertain: standalone nuspec files exist for this library (nuspec\SAIF.Apps\SAIF.Application.Services.AudioVideo.nuspec, .32.nuspec) but no pipeline YAML in this repository's Pipelines\ folder builds or packs SAIF.Application.Services.AudioVideo.csproj or references either nuspec — whether packaging happens via a pipeline defined outside this repository is unknown.**
CallRexServiceProxy embeds a service-account credential (_userId = "AI", _pwd = "AudioImporter") as plain string literals rather than resolving it via IEnvironmentService.GetSecureConfigSetting — a design constraint of the current vendor-authentication approach rather than an environment-variance setting.

Note: Statements marked with * were inferred from code structure, naming conventions, or contextual evidence where direct confirmation was not available in source artifacts. Statements marked with ** could not be confirmed; treat as unknown until verified.

Sources¶

Application\SAIF.Application.Services.AudioVideo\SAIF.Application.Services.AudioVideo.csproj
Application\SAIF.Application.Services.AudioVideo\packages.config
Application\SAIF.Application.Services.AudioVideo\app.config
Application\SAIF.Application.Services.AudioVideo\Core\Services\IAudioVideoService.cs
Application\SAIF.Application.Services.AudioVideo\Core\Contracts\AudioVideo\IRecordingSystem.cs
Application\SAIF.Application.Services.AudioVideo\Core\Contracts\AudioVideo\IImportStatusManager.cs
Application\SAIF.Application.Services.AudioVideo\Services\Utilities\AudioVideo\AudioVideoService.cs
Application\SAIF.Application.Services.AudioVideo\Services\Utilities\AudioVideo\AudioVideoValidator.cs
Application\SAIF.Application.Services.AudioVideo\Services\Utilities\AudioVideo\ImportStatusManager.cs
Application\SAIF.Application.Services.AudioVideo\Services\Utilities\AudioVideo\CallRecordingExtensions.cs
Application\SAIF.Application.Services.AudioVideo\Services\Utilities\AudioVideo\RecordingSystem.cs
Application\SAIF.Application.Services.AudioVideo\Services\ClientProxies\ThirdParty\CallRexServiceProxy.cs
Application\SAIF.Application.Services.AudioVideo\Services\ClientProxies\ThirdParty\CallRexStateServiceProxy.cs
Application\SAIF.Application.Services.AudioVideo\Services\ClientProxies\ThirdParty\AgentStateCallback.cs
Application\SAIF.Application.Services.AudioVideo\Data\Mappings\AudioImportStatusMap.cs
Application\SAIF.Application.Services.AudioVideo\Data\Mappings\RecordingMap.cs
nuspec\SAIF.Apps\SAIF.Application.Services.AudioVideo.nuspec
nuspec\SAIF.Apps\SAIF.Application.Services.AudioVideo.32.nuspec