Troubleshooting Guide

Debug and resolve common BimlScript compilation and runtime issues.

Enable Build Logging

Logging helps identify where and why builds fail.

BimlStudio Logging

1. Click Start Logging on the Build & Deploy ribbon
2. View log entries in the Logging window
3. Look for error entries with timestamps

Configure LoggingManager in Code

<#@ import namespace="Varigence.Utility.Logging" #>
<#
var loggingManager = new LoggingManager(Logging.LoggingMode.File) {
    IsEnabled = true,
    LogFilePath = @"C:\BimlLogs\build.log"
};
LoggingManager.RegisterDefaultLoggingManager(loggingManager);
#>

Logging Modes

Mode	Purpose	Access
EventDriven	Real-time output in BimlStudio	Subscribe to LogMessage event
FullText	Complete log as string	LoggingManager.FullLog
List	Log entries as objects	LoggingManager.LogEvents
File	Write to external file	Set LogFilePath property

Logging Detail Levels

Level	What's Logged
Files	File compilation start/end events
Objects	Individual Biml object events
Queries	All database queries with timing

<#
var loggingManager = new LoggingManager(Logging.LoggingMode.File) {
    IsEnabled = true,
    LogFilePath = @"C:\BimlLogs\build.log",
    LoggingDetail = Logging.LoggingDetail.Files | Logging.LoggingDetail.Queries
};
#>

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Using the Preview Pane

Preview expanded Biml before building to catch errors early.

How to Use

1. Right-click the .biml file in Solution Explorer
2. Select Expand to BimlScript or Preview Biml
3. Review the generated XML for errors

What to Look For

• Malformed XML: Missing closing tags, invalid characters
• Empty collections: Loops that produce no output
• Wrong references: Connection names that don't exist

Preview Example

Source BimlScript:

<# foreach (var table in tables) { #>
<Table Name="<#= table.Name #>" />
<# } #>

Preview shows:

<Table Name="Customer" />
<Table Name="Order" />
<Table Name="Product" />

If preview is empty, your tables collection has no items.

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Common Compilation Errors

Object Reference Errors

Error: Object reference not set to an instance of an object

Causes and Solutions:

Cause	Solution
RootNode object doesn't exist yet	Use tier directive to order file compilation
Connection not found	Verify connection exists in a lower-tier file
Collection is empty	Check GetDatabaseSchema() results

Fix with tiers:

<!-- Connections.biml - tier 10 (compiles first) -->
<#@ template tier="10" #>
<Biml xmlns="http://schemas.varigence.com/biml.xsd">
  <Connections>
    <OleDbConnection Name="Source" ConnectionString="..." />
  </Connections>
</Biml>

<!-- Packages.biml - tier 20 (compiles second, can reference connections) -->
<#@ template tier="20" #>
<# var conn = RootNode.OleDbConnections["Source"]; #>

Invalid XML Errors

Error: The 'X' start tag does not match the end tag of 'Y'

Common Causes:

1. BimlScript output contains special characters
2. Closing tags in wrong order
3. Unclosed control blocks

Debug technique:

<#
// Add debugging output
System.Diagnostics.Debug.WriteLine($"Processing table: {table.Name}");
#>

Connection Not Found

Error: Cannot find connection named 'ConnectionName'

Checklist:

• Connection name matches exactly (case-sensitive)
• Connection file compiles at lower tier
• Connection uses correct element type (OleDbConnection vs AdoNetConnection)

Verify connections exist:

<#
// List all available connections
foreach (var conn in RootNode.Connections) {
    System.Diagnostics.Debug.WriteLine($"Found connection: {conn.Name}");
}
#>

Import Options Issues

Error: Database import returns empty results

Common Fixes:

<#
var sourceConnection = RootNode.OleDbConnections["Source"];

// Include specific schemas only
var schemas = new List<string>{"dbo", "Sales"};

// Exclude views, foreign keys for cleaner import
var options = ImportOptions.ExcludeViews |
              ImportOptions.ExcludeForeignKey |
              ImportOptions.ExcludeColumnDefault;

var result = sourceConnection.GetDatabaseSchema(schemas, null, options);

// Check what was imported
System.Diagnostics.Debug.WriteLine($"Tables found: {result.TableNodes.Count()}");
#>

---

Custom Validation

Using ValidationReporter

Add custom validation messages during compilation:

<#@ import namespace="Varigence.Biml.Extensions" #>
<#
foreach (var table in RootNode.Tables) {
    // Error: Stop compilation
    if (string.IsNullOrEmpty(table.Name)) {
        ValidationReporter.Report(Severity.Error,
            "Table name cannot be empty",
            table);
    }

    // Warning: Continue but alert user
    if (table.Columns.Count == 0) {
        ValidationReporter.Report(Severity.Warning,
            $"Table {table.Name} has no columns defined",
            table);
    }

    // Information: Just informational
    if (table.GetTag("LoadType") == null) {
        ValidationReporter.Report(Severity.Information,
            $"Table {table.Name} missing LoadType annotation",
            table);
    }
}
#>

Severity Levels

Severity	Effect
Error	Stops compilation, must fix
Warning	Continues compilation, should fix
Information	Continues compilation, optional

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Debug Utilities

GetBiml() Method

View the Biml representation of any object:

<#
foreach (var table in RootNode.Tables) {
    // Output table's Biml to debug
    System.Diagnostics.Debug.WriteLine(table.GetBiml());
}
#>

ObjectTag for Tracing

Add tracking information to objects:

<#@ template tier="10" #>
<Biml xmlns="http://schemas.varigence.com/biml.xsd">
  <Tables>
    <Table Name="Customer" SchemaName="dbo">
      <Annotations>
        <Annotation Tag="Source">CRM Database</Annotation>
        <Annotation Tag="Owner">Data Team</Annotation>
        <Annotation Tag="LastReviewed">2024-01-15</Annotation>
      </Annotations>
      <Columns>
        <Column Name="ID" DataType="Int32" />
      </Columns>
    </Table>
  </Tables>
</Biml>

<!-- Later, read the tags -->
<#
var table = RootNode.Tables["Customer"];
var source = table.GetTag("Source");  // Returns "CRM Database"
#>

Conditional Compilation

Skip problematic objects during debugging:

<#
foreach (var table in RootNode.Tables) {
    // Skip specific tables for debugging
    if (table.Name == "ProblemTable") {
        System.Diagnostics.Debug.WriteLine($"Skipping {table.Name}");
        continue;
    }

    // Only process if enabled
    if (table.GetTag("Enabled") != "false") {
        #>
        <Package Name="Load_<#= table.Name #>">
          <!-- Package content -->
        </Package>
        <#
    }
}
#>

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Tier Ordering Issues

Understanding Tiers

Biml files compile in tier order (lowest first). Files in the same tier compile together.

Tier 10: Connections.biml
Tier 20: Tables.biml (can reference connections)
Tier 30: Packages.biml (can reference tables and connections)

Common Tier Problems

Problem	Symptom	Solution
No tier specified	Random compilation order	Add <#@ template tier="X" #>
Reference before definition	Object not found errors	Lower tier for referenced object
Circular reference	Compilation fails	Reorganize into separate files

Recommended Tier Strategy

Tier Range	Content
1-10	Connections, file connections
11-20	Database schemas, tables
21-30	Stored procedures, views
31-40	Individual SSIS packages
41-50	Master workflow packages

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SSIS-Specific Issues

Data Flow Errors

Issue: Columns don't map correctly

Debug steps:

1. Preview the Biml to see column definitions
2. Verify source and destination column names match
3. Check data type compatibility

<#
foreach (var col in table.Columns) {
    System.Diagnostics.Debug.WriteLine(
        $"Column: {col.Name}, Type: {col.DataType}, Length: {col.Length}"
    );
}
#>

Package Won't Execute

Checklist:

• Connection strings are valid for runtime
• Table references exist in target database
• Variables are properly scoped

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Quick Diagnostic Checklist

When builds fail, check in this order:

1. Tier ordering: Are files compiling in correct order?
2. Connection names: Exact match, case-sensitive?
3. Empty collections: Does GetDatabaseSchema() return data?
4. XML validity: Use Preview to see expanded Biml
5. Syntax errors: Check for unclosed nuggets <# ... #>
6. Import namespaces: All required <#@ import ...#> present?

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Next Steps

• Common Patterns - Reusable solutions
• Biml Basics - Core syntax reference
• Introduction to BimlScript - Code nuggets and directives