# Reusable Subflow Library > The Subflow Library provides pre-built, production-ready subflows that accelerate flow development and enforce best practices. - Skill: `tools-only/reusable-subflow-library` (Agent Skill, multi-file: 3 files) - Install (CLI): `npx skillmds@latest add tools-only/reusable-subflow-library` - Raw SKILL.md: https://api.skillmd.com/api/skills/tools-only/reusable-subflow-library/raw - Safety review: pending (external: skill-scanner PASS, skillspector CAUTION) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tools-only (https://skillmd.com/u/tools-only) - Updated: 2026-09-29 - Page: https://skillmd.com/skills/tools-only/reusable-subflow-library --- # Reusable Subflow Library ## Overview The Subflow Library provides pre-built, production-ready subflows that accelerate flow development and enforce best practices. Instead of recreating common patterns, use these standardized components to build flows faster while maintaining consistency. **Benefits:** - ⚑ **Faster Development**: Pre-built patterns save 30-50% development time - πŸ”’ **Built-in Error Handling**: Fault paths and logging included - βœ… **Best Practices**: Bulkified, tested, and validated - πŸ”„ **Reusable**: One subflow, many parent flows - πŸ“Š **Maintainable**: Update once, improve everywhere --- ## Available Subflows ### 1. Sub_LogError **Purpose**: Structured error logging for fault paths **File**: `templates/subflows/subflow-error-logger.xml` **When to Use**: - In fault paths of DML operations - When you need to capture and track flow failures - For production observability and debugging **Input Variables**: - `varFlowName` (String): Name of the calling flow - `varRecordId` (String): ID of the record being processed - `varErrorMessage` (String): Error message (typically `$Flow.FaultMessage`) **Output Variables**: None **Example**: ```xml Log_Update_Error Sub_LogError varFlowName RTF_Account_UpdateIndustry varRecordId $Record.Id varErrorMessage $Flow.FaultMessage ``` **Prerequisites**: Create Flow_Error_Log__c custom object with fields: - `Flow_Name__c` (Text, 255) - `Record_Id__c` (Text, 18) - `Error_Message__c` (Long Text Area, 32,768) **Related**: [Error Logging Example](../examples/error-logging-example.md) --- ### 2. Sub_SendEmailAlert **Purpose**: Standard email notifications **File**: `templates/subflows/subflow-email-alert.xml` **When to Use**: - Send notifications when certain conditions are met - Alert users about flow completion or errors - Standardize email formatting across flows **Input Variables**: - `varEmailAddresses` (String): Comma-separated email addresses - `varEmailSubject` (String): Email subject line - `varEmailBody` (String): Email body content **Output Variables**: None **Example**: ```xml Notify_Manager Sub_SendEmailAlert varEmailAddresses $Record.Manager.Email varEmailSubject High-Value Opportunity Created varEmailBody A new opportunity worth {!$Record.Amount} has been created. ``` **Best Practices**: - Use formula fields or text templates to build dynamic email bodies - Consider using email templates instead for complex HTML emails - Validate email addresses before passing to subflow --- ### 3. Sub_ValidateRecord **Purpose**: Common validation patterns **File**: `templates/subflows/subflow-record-validator.xml` **When to Use**: - Validate required fields before DML operations - Check business rules before proceeding - Return validation status to parent flow **Input Variables**: - `varFieldValue` (String): Field value to validate **Output Variables**: - `varIsValid` (Boolean): `true` if validation passed, `false` otherwise - `varValidationMessage` (String): Validation result message **Example**: ```xml Validate_Industry Sub_ValidateRecord varFieldValue $Record.Industry true Check_Validation Valid Validate_Industry.varIsValid EqualTo true Proceed_With_Update Show_Error_Screen ``` **Extension**: Customize the validation logic in the subflow for your specific needs: - Add more complex rules (regex, format checks) - Validate multiple fields - Check against external systems --- ### 4. Sub_UpdateRelatedRecords **Purpose**: Bulk update pattern with error handling **File**: `templates/subflows/subflow-bulk-updater.xml` **When to Use**: - Update collections of related records - Maintain bulkification best practices - Centralize common update logic **Input Variables**: - `colRecordsToUpdate` (SObject Collection): Collection of records to update - `varNewValue` (String): New value to assign (customize for your field type) **Output Variables**: None **Example**: ```xml Loop_Through_Contacts Get_Related_Contacts Asc Add_To_Collection Call_Bulk_Updater Add_To_Collection colContactsToUpdate Add Loop_Through_Contacts Loop_Through_Contacts Call_Bulk_Updater Sub_UpdateRelatedRecords colRecordsToUpdate colContactsToUpdate varNewValue $Record.Industry ``` **Key Pattern**: βœ… **Correct**: Loop β†’ Add to Collection β†’ (Outside Loop) β†’ Call Subflow with Collection ❌ **Incorrect**: Loop β†’ Call Subflow β†’ (DML in loop!) --- ### 5. Sub_QueryRecordsWithRetry **Purpose**: Query with built-in error handling **File**: `templates/subflows/subflow-query-with-retry.xml` **When to Use**: - Query related records with fault handling - Standardize query patterns - Log query failures for troubleshooting **Input Variables**: - `varAccountId` (String): Filter criteria (customize for your query) **Output Variables**: - Automatically stores query results (use `storeOutputAutomatically="true"`) **Example**: ```xml Get_Related_Contacts Sub_QueryRecordsWithRetry varAccountId $Record.Id true Check_Results Contacts_Found Get_Related_Contacts IsNull false Process_Contacts No_Contacts_Path ``` **Customization**: Modify the query filters in the template for your specific object and criteria. --- ## Deployment Guide ### Step 1: Deploy Subflows to Your Org ```bash # Deploy all subflows at once sf project deploy start \ --source-dir templates/subflows/ \ --target-org myorg # Or deploy individually sf project deploy start \ --source-dir templates/subflows/subflow-error-logger.xml \ --target-org myorg ``` ### Step 2: Activate Subflows 1. Navigate to **Setup β†’ Flows** 2. Find each subflow (Sub_LogError, Sub_SendEmailAlert, etc.) 3. Click **Activate** **⚠️ Important**: Deploy Sub_LogError first if other subflows use it for error handling. ### Step 3: Create Required Custom Objects For **Sub_LogError**, create the Flow_Error_Log__c object: ```bash # Using Salesforce CLI sf data create record \ --sobject CustomObject \ --values "FullName=Flow_Error_Log__c Label='Flow Error Log' PluralLabel='Flow Error Logs'" ``` Or manually in Setup β†’ Object Manager β†’ Create β†’ Custom Object. --- ## Usage Patterns ### Pattern 1: Orchestrated Error Handling Use Sub_LogError consistently across all flows: ``` Parent Flow β”œβ”€β”€ DML Operation 1 β†’ [Fault] β†’ Sub_LogError β”œβ”€β”€ DML Operation 2 β†’ [Fault] β†’ Sub_LogError └── Subflow Call β†’ [Fault] β†’ Sub_LogError ``` ### Pattern 2: Modular Notifications Centralize all email logic in Sub_SendEmailAlert: ``` Record-Triggered Flow β”œβ”€β”€ Decision: High Value? β”‚ β”œβ”€β”€ Yes β†’ Sub_SendEmailAlert(Manager) β”‚ └── No β†’ End └── Decision: Overdue? β”œβ”€β”€ Yes β†’ Sub_SendEmailAlert(Owner) └── No β†’ End ``` ### Pattern 3: Validation Pipeline Chain validation subflows before DML: ``` Screen Flow β”œβ”€β”€ Sub_ValidateRecord(Required Fields) β”‚ └── Invalid? β†’ Show Error β”œβ”€β”€ Sub_ValidateRecord(Business Rules) β”‚ └── Invalid? β†’ Show Error └── All Valid β†’ Create Record ``` --- ## Best Practices ### βœ… DO: 1. **Deploy Once, Reference Everywhere**: Activate subflows in your org, then reference them in multiple parent flows 2. **Use Naming Conventions**: Start subflow names with `Sub_` for easy identification 3. **Add Fault Paths**: Connect all DML operations in subflows to error handlers 4. **Document Inputs/Outputs**: Use clear variable names (varFieldName, colRecordCollection) 5. **Version Control**: Track subflow changes and test before updating active versions ### ❌ DON'T: 1. **Don't Copy-Paste Subflows**: Reference the deployed subflow instead of duplicating logic 2. **Don't Skip Error Handling**: All subflows should handle their own errors gracefully 3. **Don't Hardcode Values**: Use input variables for flexibility 4. **Don't Create DML in Loops**: Use Sub_UpdateRelatedRecords pattern for bulk operations 5. **Don't Forget Testing**: Test subflows independently before using in parent flows --- ## Testing Your Subflows ### Unit Testing Individual Subflows 1. Create a test flow that calls the subflow 2. Pass various input combinations (valid, invalid, null) 3. Verify output variables and behavior 4. Check error logs if using Sub_LogError ```bash # Example: Test Sub_LogError sf data query \ --query "SELECT Flow_Name__c, Error_Message__c FROM Flow_Error_Log__c ORDER BY CreatedDate DESC LIMIT 5" \ --target-org myorg ``` ### Integration Testing in Parent Flows 1. Use subflows in record-triggered flows 2. Test with bulk data (200+ records) 3. Verify subflow doesn't cause governor limit errors 4. Check execution time in debug logs --- ## Customization Guide ### Extending Subflows All subflows are templatesβ€”customize for your needs: 1. **Clone the subflow**: Create a copy (e.g., `Sub_LogError_WithEmail`) 2. **Add custom logic**: Extend functionality while keeping core pattern 3. **Maintain naming convention**: Keep `Sub_` prefix for discoverability ### Example: Enhanced Error Logger Extend Sub_LogError to send Platform Events: ```xml Publish_Error_Event Flow_Error__e Flow_Name__c varFlowName ``` --- ## Performance Considerations ### Governor Limits - **Subflow Depth**: Maximum 50 levels of nested subflows (avoid deep nesting) - **DML Statements**: Each subflow DML counts toward 150 limit - **SOQL Queries**: Each subflow query counts toward 100 limit ### Optimization Tips 1. **Batch Operations**: Use Sub_UpdateRelatedRecords for bulk updates 2. **Minimize Subflow Calls**: Call once with collections vs. multiple times with single records 3. **Cache Results**: Store subflow outputs in variables to avoid repeated calls --- ## Troubleshooting ### "Subflow not found" Error - βœ… Verify subflow is activated in target org - βœ… Check API name matches exactly (`Sub_LogError`, not `Sub_Log_Error`) - βœ… Deploy subflow before deploying parent flow ### "Input variable not found" Error - βœ… Verify variable names match subflow definition - βœ… Check variable data types (String vs. SObject Collection) - βœ… Ensure required inputs are provided ### Performance Issues - βœ… Check debug logs for subflow execution time - βœ… Avoid calling subflows inside loops - βœ… Use bulk operations with collections --- ## Version History | Version | Date | Changes | |---------|------|---------| | 1.0 | 2024-11-30 | Initial library: 5 subflows (LogError, EmailAlert, Validator, BulkUpdater, QueryWithRetry) | --- ## Related Documentation - [Error Logging Example](../examples/error-logging-example.md) - Detailed Sub_LogError usage - [Orchestration Guide](orchestration-guide.md) - Parent-child flow patterns - [Flow Best Practices](flow-best-practices.md) - Flow guidelines and security --- ## Support For issues or questions: 1. Check subflow XML for correct variable names and types 2. Test subflow independently before using in parent flow 3. Review error logs in Flow_Error_Log__c (if using Sub_LogError) 4. Check debug logs for detailed execution information **Happy flow building! πŸš€**