Roslyn Analyzers

ALPHA RELEASE

Switchboard is currently in preview (v0.1.0-preview.17). APIs may change between releases.

Switchboard includes Roslyn analyzers that provide compile-time validation of your contact flows. These analyzers catch errors as you write code, before you even build or deploy.

What Are Roslyn Analyzers?

Roslyn analyzers are code analysis tools that run inside the C# compiler. They examine your code and provide:

• Real-time error detection - See issues while typing
• Code fixes - Automatic corrections
• Warnings - Potential issues
• Best practice suggestions - Improve code quality

Built-In Analyzer Rules

SWB001: Queue Reference Not Found

Ensures queue references are valid.

// ❌ Error
[TransferToQueue("NonExistent")]
public partial void Transfer();
// Error SWB001: Queue 'NonExistent' is not defined

// ✅ Fix: Define queue first
[Queue("Support")]
[ContactFlow("MyFlow")]
public partial class MyFlow
{
    [TransferToQueue("Support")]  // ✅ OK
    public partial void Transfer();
}

###SWB002: Missing Required Parameter

// ❌ Error
[GetUserInput(MaxDigits = 4)]  // Missing 'Prompt'
public partial void GetInput();
// Error SWB002: GetUserInput requires 'Prompt' parameter

// ✅ Fix
[GetUserInput("Enter PIN", MaxDigits = 4)]
public partial void GetInput();

SWB003: Multiple Action Attributes

// ❌ Error
[Message("Hello")]
[TransferToQueue("Sales")]
public partial void Action();
// Error SWB003: Multiple action attributes not allowed

// ✅ Fix: Separate into two methods
[Message("Hello")]
public partial void SayHello();

[TransferToQueue("Sales")]
public partial void Transfer();

See: Reference: Analyzers for all analyzer rules.

Code Fixes

Analyzers provide automatic fixes:

// Typo detected
[TransferToQueue("Suport")]
public partial void Transfer();

// 💡 Suggested fix (Ctrl+. or Alt+Enter)
// "Did you mean 'Support'?"

// Apply fix → automatically corrected
[TransferToQueue("Support")]
public partial void Transfer();

Configuring Analyzers

Suppress Specific Warnings

#pragma warning disable SWB005
[Loop(Target = nameof(Retry), MaxIterations = 10)]
public partial void Retry();
#pragma warning restore SWB005

Configure in .editorconfig

# .editorconfig
[*.cs]

# Treat SWB001 as error
dotnet_diagnostic.SWB001.severity = error

# Treat SWB005 as warning
dotnet_diagnostic.SWB005.severity = warning

# Disable SWB007
dotnet_diagnostic.SWB007.severity = none

Next Steps

• Reference: Analyzers - Complete rule reference
• Source Generators - Code generation
• Flow Validation - All validation layers