# 🌐 URL Support for Cloud Deployment
When your MCP server is deployed to the cloud, it can't access local files. This guide shows how to extend the tools to support URL-based file access.
## 🔗 Current Challenge
**Local Development** (works):
```javascript
{
"filePath": "./my-data.xlsx" // ✅ Local file access
}
```
**Cloud Deployment** (doesn't work):
```javascript
{
"filePath": "./my-data.xlsx" // ❌ File not found on server
}
```
## 💡 Solution: URL Support
### Option 1: Public URLs
Support files hosted on the internet:
```javascript
{
"filePath": "https://example.com/public-data.xlsx" // ✅ Works in cloud
}
```
### Option 2: Base64 Content
Accept file content directly:
```javascript
{
"fileContent": "data:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;base64,UEsDBBQA...",
"fileName": "data.xlsx"
}
```
## 🛠️ Implementation Guide
### Step 1: Add URL Detection
```javascript
// In excel-analyser-mcp.js
const isUrl = (path) => {
try {
new URL(path);
return true;
} catch {
return false;
}
};
```
### Step 2: Add HTTP Fetch Function
```javascript
const fetchFileFromUrl = async (url) => {
const response = await fetch(url);
if (!response.ok) {
throw new Error(`Failed to fetch file: ${response.status} ${response.statusText}`);
}
return await response.arrayBuffer();
};
```
### Step 3: Modify read_excel Tool
```javascript
server.tool(
"read_excel",
{
filePath: z.string().describe("Path to Excel/CSV file on disk OR public URL"),
columns: z.array(z.string()).optional()
},
async ({ filePath, columns }) => {
try {
let buffer;
if (isUrl(filePath)) {
// Fetch from URL
console.error(`Fetching file from URL: ${filePath}`);
buffer = Buffer.from(await fetchFileFromUrl(filePath));
} else {
// Read local file (for local development)
const fs = await import('fs/promises');
try {
await fs.access(filePath);
buffer = await fs.readFile(filePath);
} catch {
return {
content: [{
type: "text",
text: `File not found: ${filePath}. For cloud deployment, use public URLs instead of local paths.`
}]
};
}
}
// Rest of the existing logic...
} catch (error) {
return {
content: [{
type: "text",
text: `Error: ${error.message}`
}]
};
}
}
);
```
## 📋 Usage Examples
### For Users of Your Deployed Server
**Instead of local files**:
```json
{
"name": "read_excel",
"arguments": {
"filePath": "./data.xlsx" // ❌ Won't work in cloud
}
}
```
**Use public URLs**:
```json
{
"name": "read_excel",
"arguments": {
"filePath": "https://github.com/user/repo/raw/main/data.xlsx" // ✅ Works!
}
}
```
**Or Google Sheets (as CSV)**:
```json
{
"name": "read_excel",
"arguments": {
"filePath": "https://docs.google.com/spreadsheets/d/YOUR_SHEET_ID/export?format=csv"
}
}
```
**Or Dropbox/OneDrive public links**:
```json
{
"name": "read_excel",
"arguments": {
"filePath": "https://dropbox.com/s/abc123/data.xlsx?dl=1"
}
}
```
## 🔐 Security Considerations
### For Production:
1. **URL Validation**
```javascript
const allowedDomains = ['github.com', 'docs.google.com', 'dropbox.com'];
const urlObj = new URL(filePath);
if (!allowedDomains.includes(urlObj.hostname)) {
throw new Error('Domain not allowed');
}
```
2. **File Size Limits**
```javascript
const MAX_FILE_SIZE = 50 * 1024 * 1024; // 50MB
if (buffer.length > MAX_FILE_SIZE) {
throw new Error('File too large');
}
```
3. **Rate Limiting**
```javascript
// Track requests per IP/session
const requestCounts = new Map();
// Implement rate limiting logic
```
## 📖 User Documentation
Update your README to include:
```markdown
## 🌐 Cloud Usage
When using the deployed server, provide public URLs instead of local file paths:
### ✅ Supported URL Sources:
- **GitHub**: `https://github.com/user/repo/raw/main/file.xlsx`
- **Google Sheets**: `https://docs.google.com/spreadsheets/d/ID/export?format=csv`
- **Dropbox**: `https://dropbox.com/s/abc123/file.xlsx?dl=1`
- **OneDrive**: Public share links
- **Any public web server**: Direct file URLs
### 📝 Example Usage:
```json
{
"name": "read_excel",
"arguments": {
"filePath": "https://github.com/user/data/raw/main/sales.xlsx",
"columns": ["date", "revenue", "region"]
}
}
```
### 🚫 What Doesn't Work:
- Local file paths: `./data.xlsx`
- Private URLs requiring authentication
- Files larger than 50MB
```
## 🧪 Testing URL Support
Create a test script:
```javascript
// test-url-support.js
const testUrls = [
'https://github.com/contactakagrawal/excel-analyser-mcp/raw/main/dummy_excel_file.xlsx',
'https://docs.google.com/spreadsheets/d/1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms/export?format=csv'
];
testUrls.forEach(async (url) => {
console.log(`Testing: ${url}`);
// Test your MCP server with this URL
});
```
## 🎯 Next Steps
1. **Implement URL support** in your tools
2. **Test with public URLs**
3. **Update documentation**
4. **Deploy to Railway**
5. **Share with users**
This approach makes your cloud-deployed MCP server much more useful! 🚀
