data-flow-analysis

Data Flow Analysis Command

Trace how specific data moves through the entire system - from where it enters, through all transformations, to where it's stored or output. This helps understand data pipelines, transformations, and dependencies.

Objective

For a given data entity or type, map its complete journey through the system:

• Entry points (APIs, file uploads, integrations)
• All transformations and enrichments
• Storage locations (databases, caches, files)
• Output destinations (APIs, reports, external systems)
• Access patterns (who reads/writes it)

Step 1: Data Entity Identification

If Entity Specified

• Find the entity definition (model, schema, type)
• Identify all fields and their types
• Note any computed or derived fields

If No Entity Specified

• List main data entities in the system
• Suggest which to analyze based on:
  • Core business entities
  • Entities with complex transformations
  • Data that flows between multiple systems

Output Format

## Data Entity: [EntityName]

**Definition Location**: `file_path:line_number`

**Schema**:
```typescript
interface EntityName {
  id: string;           // Primary identifier
  field1: string;       // [Purpose]
  field2: number;       // [Purpose]
  computed: boolean;    // Derived from [source]
  relations: {
    relatedEntity: RelatedType;
  };
}

Business Purpose: [What this data represents in business terms]

Data Classification:

• Sensitivity: [Public/Internal/Confidential/PII]
• Lifecycle: [How long it's retained]
• Compliance: [Any regulatory requirements]

## Step 2: Data Entry Points

Identify all ways data enters the system:

### Entry Point Types
- API endpoints (POST/PUT requests)
- File uploads
- Data imports/migrations
- External system integrations
- User input forms
- Scheduled data fetches
- Event consumers

### Output Format
```markdown
## Data Entry Points

### Entry Point 1: [Name]
**Type**: [API/Upload/Integration/etc.]
**Location**: `file_path:line_number`

**How Data Arrives**:
```json
{
  "rawField1": "value",
  "rawField2": 123,
  "sourceSystem": "external-api"
}

Validation Applied:

• ✓ Type checking: [What's validated]
• ✓ Business rules: [What's enforced]
• ✗ Missing validation for: [What's not checked]
• Location: file_path:line_number

Initial Transformation:

• [Transformation 1] at file_path:line_number
• [Transformation 2] at file_path:line_number

After Entry Processing:

{
  "id": "generated-uuid",
  "field1": "NORMALIZED_VALUE",
  "field2": 123,
  "status": "pending",
  "createdAt": "2024-01-01T00:00:00Z"
}

Error Handling:

• Invalid data: [How it's handled]
• Duplicate detection: [Yes/No] at file_path:line_number
• Partial data: [How it's handled]

Volume/Frequency:

• Estimated: [X] records per [time period]
• Peak times: [When]