Consumption¶

A consumer obtains fax delivery by constructing FaxServiceProxy per call from SAIF.Services.WCF.Services.FaxService, which is in turn part of SAIF.Services.Web.Proxies and documented as a consuming library at SAIF.Services.Web.Proxies overview.

Reference style¶

Field	Value
Mechanism	Service Reference (svcutil)
Declared in	`Services/SAIF.Services.Web.Proxies/Service References/Fax/Reference.svcmap`
Generated artifacts	`Services/SAIF.Services.Web.Proxies/Service References/Fax/Reference.cs`
Target framework	.NET Framework 4.6.2
Regeneration command	Visual Studio "Update Service Reference"

Construction¶

public FaxServiceProxy(string serviceUrl)
{
    Enforce.ArgumentNotNullOrWhiteSpace(serviceUrl, nameof(serviceUrl));
    var binding = new BasicHttpBinding(BasicHttpSecurityMode.TransportCredentialOnly)
    {
        MaxReceivedMessageSize = int.MaxValue,
        MaxBufferSize = int.MaxValue,
        ReaderQuotas = { MaxArrayLength = int.MaxValue }
    };
    binding.Security.Transport.ClientCredentialType = HttpClientCredentialType.Windows;
    webService = new FaxServiceSoapClient(binding, new EndpointAddress(serviceUrl));
}

Step	Requirement
Endpoint address	Constructor argument, resolved by `FaxService` from `WcfEnvironmentService.GetConfigSetting(EnvironmentConfigKeys.FaxSoapServiceUrl)`
Binding	Constructed in code — `BasicHttpBinding(TransportCredentialOnly)` with Windows client credentials
Credentials	Ambient Windows identity of the process, or the impersonated identity if the WCF host impersonates*
Initialization	Single-constructor

Endpoint configuration¶

Setting	Value	Source	Changeable without a rebuild
Endpoint address	`http://websvcprod/webservices/SAIFFaxService/faxservice.asmx`	`Services/SAIF.Services.WebApi/EnvironmentApi/App_Data/environments.xml:16,35,54,73,91,109`	Yes
Binding configuration	Constructed in code	`Services/SAIF.Services.Web.Proxies/FaxServiceProxy.cs:18-28`	No
Security mode	`TransportCredentialOnly`	`FaxServiceProxy.cs:18`	No

The app.config <client><endpoint name="FaxServiceSoap"> entry (Services/SAIF.Services.Web.Proxies/app.config:60, address api.saif.com) is present but is not used at runtime, because the wrapper supplies an explicit Binding and EndpointAddress to the generated constructor.

Resilience¶

Concern	Finding	Configurable by consumer	Source	Tech debt
Timeout	None configured — binding defaults apply	No	`FaxServiceProxy.cs:18-28`	Yes
Retry	None configured	No	—	Yes
Circuit breaking	None configured	No	—	Yes
Thread safety	Not determined from source	—	—	No
Cancellation	Not supported — no cancellation on any call site	—	`FaxServiceProxy.cs:43`	Yes
Message size limits	`MaxReceivedMessageSize`/`MaxBufferSize`/`MaxArrayLength` all set to `int.MaxValue`	Yes	`FaxServiceProxy.cs:20-22`	Yes

The unbounded quotas are copied boilerplate rather than a deliberate choice — the response is empty, so the practical exposure is small, but the setting removes a real safeguard against an oversized response — see Tech debt.

Disposal¶

Aspect	Finding
Disposal performed	`Close()`
Faulted channel handled	No — a faulted channel throws from disposal and masks the original failure*
Wrapper responsibility	`FaxServiceProxy` disposes the generated proxy; `FaxService.Dispose()` disposes the wrapper
Source	`Services/SAIF.Services.Web.Proxies/FaxServiceProxy.cs:57-65`; `Services/SAIF.Services.WCF/Services/FaxService.cs:59-67`

public void Dispose()
{
    webService.Close();
}

Error handling for consumers¶

Failure	Surfaces as	Consumer action
Service unreachable	`EndpointNotFoundException`†	None — propagates through `FaxService.SendFax` to WCF
SOAP fault returned	`FaultException`†	None — propagates unchanged
Timeout exceeded	`TimeoutException`†	None — propagates unchanged
Response larger than the message size limit	Not applicable — the response is empty	—
Empty or absent output message	Not applicable — `Send` is one-way	—

With multiple recipients, a mid-loop failure at FaxService.SendFax leaves earlier recipients faxed and later ones not, and the caller receives no indication of which; the temp file write to fullFilePath is also not cleaned up when a Send call throws, because the delete happens only after the loop completes.

Usage examples¶

// Send a fax to each recipient in the request, using a temp copy of the document
foreach (var recipient in config.Recipients)
{
    proxy.SendFax(recipient, fullFilePath);
}

Scenario	Operations used	Notes
Send one document to multiple fax recipients	`Send`	Called once per recipient from `FaxService.SendFax`

Lifecycle guidance¶

Question	Answer
Construct once or per call	Per service instance* — constructed from `OperationContext.Current` in the `FaxService` constructor
Disposable	Yes (`IDisposable`)
Safe to share across threads	Not determined from source

Note: Statements marked with † are derived from dependency library documentation via the Legends CLI. Statements marked with * were inferred from code structure or contextual evidence.

Sources¶

Services/SAIF.Services.Web.Proxies/FaxServiceProxy.cs
Services/SAIF.Services.WCF/Services/FaxService.cs
Services/SAIF.Services.Web.Proxies/app.config