# OfficeCLI Validate Command: OpenXML Schema Checking for Office Documents

> Use OfficeCLI validate command for OpenXML schema checking. Detect structural violations in Word, Excel, and PowerPoint files efficiently via CLI or JSON output.

- Repository: [OfficeAI/OfficeCLI](https://github.com/iofficeai/OfficeCLI)
- Tags: how-to-guide
- Published: 2026-08-06

---

**The `officecli validate` command uses the official Open XML SDK to check Word, Excel, and PowerPoint files against ECMA-376/ISO-29500 schema definitions, reporting structural violations through CLI output or JSON.**

OfficeCLI is a cross-platform command-line tool for Microsoft Office document automation. Its `validate` command provides **OpenXML schema checking** to ensure DOCX, XLSX, and PPTX files conform to official specifications. This article explains how the validation pipeline works, where to find the implementation in the iOfficeAI/OfficeCLI repository, and how to use it across all supported languages.

## How OfficeCLI Validation Works

The validation system follows a four-stage pipeline implemented in .NET 6 and exposed through multiple language SDKs.

### Stage 1: Command Parsing

In [`src/officecli/CommandBuilder.Mark.cs`](https://github.com/iOfficeAI/OfficeCLI/blob/main/src/officecli/CommandBuilder.Mark.cs), the CLI constructs the command hierarchy and routes the `validate` verb to its handler. The `CommandBuilder` pattern separates argument parsing from execution logic.

```csharp
// Simplified representation of the routing mechanism
// Located in: src/officecli/CommandBuilder.Mark.cs
var validateCommand = new Command("validate", "Validate file against OpenXML schema");
validateCommand.AddArgument(new Argument<FileInfo>("file"));
validateCommand.SetHandler((file) => ValidateHandler.Execute(file));

```

### Stage 2: File Loading

The handler opens the target file using the **Open XML SDK** (`DocumentFormat.OpenXml` package). It automatically detects document type and instantiates the appropriate package class:

- `WordprocessingDocument` for `.docx`
- `SpreadsheetDocument` for `.xlsx`
- `PresentationDocument` for `.pptx`

### Stage 3: Schema Validation

The core validation occurs through `OpenXmlValidator.Validate()` as implemented in the Open XML SDK. According to the iOfficeAI/OfficeCLI source code, this method:

- Parses each package part
- Compares against ECMA-376 and ISO-29500 schema definitions
- Collects `ValidationErrorInfo` objects for violations

```csharp
// Core validation pattern from the CLI implementation
// In: src/officecli/Handlers/ValidateHandler.cs (implied structure)
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Validation;

public ValidationReport RunValidation(string path)
{
    using var doc = WordprocessingDocument.Open(path, false);
    var validator = new OpenXmlValidator();
    var errors = validator.Validate(doc);
    return new ValidationReport(errors);
}

```

### Stage 4: Result Formatting

Errors are aggregated and output to standard output. The CLI supports optional JSON export for programmatic consumption.

## Using the OfficeCLI Validate Command

### Command-Line Interface

The primary interface accepts a file path and returns validation results immediately:

```bash
officecli validate ./documents/Report.docx

```

**Common options:**
- `--format json` — Output machine-readable JSON
- `--strict` — Enforce strict ISO-29500 compliance (rejects transitional extensions)

### Node.js SDK

The Node SDK in [`sdk/node/index.js`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/node/index.js) forks the native binary and returns a Promise with structured results:

```javascript
const { validate } = require('officecli');

async function checkDocument(path) {
  const report = await validate(path);
  
  if (report.errors.length === 0) {
    console.log('✓ Document passes OpenXML schema validation');
    return true;
  }
  
  console.error(`✗ ${report.errors.length} validation errors found:`);
  report.errors.forEach(err => {
    console.error(`  - ${err.description} (${err.path})`);
  });
  return false;
}

checkDocument('./documents/Report.docx')
  .catch(err => console.error('Validation failed to run:', err));

```

### Python SDK

The Python wrapper in [`sdk/python/officecli.py`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/python/officecli.py) provides a synchronous function that wraps subprocess execution:

```python
from officecli import validate

def validate_office_file(path: str) -> dict:
    """
    Validate a DOCX, XLSX, or PPTX file against OpenXML schema.
    Returns dict with 'valid' bool and 'errors' list.
    """
    report = validate(path)
    
    if report["errors"]:
        print(f"Found {len(report['errors'])} schema violations:")
        for error in report["errors"]:
            print(f"  • {error['description']} in {error['part']}")
        return {"valid": False, "details": report}
    
    print("Document conforms to OpenXML specification")
    return {"valid": True, "details": report}

# Usage

result = validate_office_file("./documents/Budget.xlsx")

```

## Key Implementation Files

Understanding these source files helps extend or debug the validation system:

| File | Purpose |
|------|---------|
| `src/officecli/officecli.csproj` | .NET 6 project definition; references `DocumentFormat.OpenXml` |
| [`src/officecli/CommandBuilder.Mark.cs`](https://github.com/iOfficeAI/OfficeCLI/blob/main/src/officecli/CommandBuilder.Mark.cs) | CLI command tree construction; registers `validate` verb |
| [`src/officecli/CommandBuilder.IntegrationStubs.cs`](https://github.com/iOfficeAI/OfficeCLI/blob/main/src/officecli/CommandBuilder.IntegrationStubs.cs) | Thin wrappers bridging CLI core to language SDKs |
| [`sdk/node/index.js`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/node/index.js) | Node.js entry point; handles binary forking and JSON parsing |
| [`sdk/python/officecli.py`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/python/officecli.py) | Python module; subprocess wrapper with error handling |

## Validation Error Types

The Open XML SDK validator reports several categories of issues detectable through OfficeCLI:

- **Structural errors** — Missing required parts or invalid relationships
- **Content type mismatches** — Parts with incorrect MIME types
- **Schema constraint violations** — Elements/attributes that violate XSD rules
- **Compatibility warnings** — Features not supported in target format version

Example error output:

```json
{
  "valid": false,
  "errors": [
    {
      "id": "Sch_InvalidElementContentExpectingComplex",
      "description": "The element has invalid child element",
      "path": "/word/document.xml",
      "element": "w:t",
      "expected": "w:rPr"
    }
  ]
}

```

## Summary

- **OfficeCLI validate** provides built-in **OpenXML schema checking** using the official Microsoft Open XML SDK
- The validation pipeline runs through [`CommandBuilder.Mark.cs`](https://github.com/iOfficeAI/OfficeCLI/blob/main/CommandBuilder.Mark.cs) → package loading → `OpenXmlValidator.Validate()` → formatted output
- **Three interfaces** are available: direct CLI, Node.js SDK ([`sdk/node/index.js`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/node/index.js)), and Python SDK ([`sdk/python/officecli.py`](https://github.com/iOfficeAI/OfficeCLI/blob/main/sdk/python/officecli.py))
- Validation covers DOCX, XLSX, and PPTX against ECMA-376 and ISO-29500 specifications
- Errors include structural, content-type, and schema constraint violations with precise location data

## Frequently Asked Questions

### What document formats does OfficeCLI validate support?

OfficeCLI validates **DOCX** (Word), **XLSX** (Excel), and **PPTX** (PowerPoint) files through the Open XML SDK's automatic format detection. The validator opens files in read-only mode and selects the appropriate `OpenXmlPackage` subclass based on content type.

### How does OfficeCLI validation differ from Office's built-in checker?

OfficeCLI performs **strict schema validation** against published ECMA-376/ISO-29500 specifications, while Microsoft Office applications often apply lenient parsing and automatic repair. A document that opens in Word may still fail OfficeCLI validation if it contains technically invalid markup that Office silently corrects.

### Can I integrate OfficeCLI validation into CI/CD pipelines?

Yes. The CLI's `--format json` option produces machine-readable output suitable for automated testing. Exit codes indicate validation status (0 for valid, non-zero for errors), and the Node/Python SDKs provide native integration with test frameworks. Example GitHub Actions step:

```yaml
- name: Validate Office documents
  run: |
    for file in docs/*.docx; do
      officecli validate "$file" --format json || exit 1
    done

```

### Where does OfficeCLI get its schema definitions?

Schema definitions are **embedded in the Open XML SDK** (`DocumentFormat.OpenXml` package) referenced in `src/officecli/officecli.csproj`. This ensures validation always uses current standards without requiring separate Schema downloads or updates.