HTTP

What is HTTP?

HTTP is a protocol that allows the fetching and transmission of resources such as HTML documents, JSON data, XML files, images, videos, or any other type of file. It operates on a client-server model where:

• Client: Makes requests for resources (e.g., FileMaker, web browsers, mobile apps)
• Server: Processes requests and returns appropriate responses (e.g., web servers, APIs)

Key Characteristics

• Stateless: Each request is independent and contains all the information needed to complete it
• Text-based: Uses human-readable headers and commands
• Extensible: Supports various content types, authentication methods, and caching strategies
• Application-layer: Built on top of lower-level protocols like TCP/IP

HTTP Methods

HTTP defines several methods (or verbs) that indicate the desired action:

• GET: Retrieve data from a server
• POST: Submit data to a server (create)
• PUT: Update existing resources
• DELETE: Remove resources
• PATCH: Apply partial modifications
• HEAD: Similar to GET but retrieves only headers (no body)
• OPTIONS: Describes communication options for a resource

HTTP in Data Integration

HTTP serves as an excellent transport mechanism for data integration because:

1. Universal support: Works across virtually all platforms and languages
2. Firewall-friendly: Uses standard ports (80/443) that are typically open in firewalls
3. Security options: HTTPS provides encryption through TLS/SSL
4. Standardized error handling: HTTP status codes provide clear feedback
5. Scalability: Supports load balancing and caching

FileMaker and HTTP

FileMaker provides several ways to use HTTP for data integration:

Insert From URL

The simplest method for making HTTP requests is the Insert From URL script step:

Insert From URL [Select ; $result ; "https://api.example.com/data" ; cURL options: "-X GET"]

cURL Options

FileMaker uses cURL syntax to configure HTTP requests:

• -X METHOD: Specify HTTP method (GET, POST, etc.)
• -H "Header: Value": Add HTTP headers
• --data "key=value": Add request body (for POST/PUT)
• --data-binary @filepath: Send file contents
• --user username:password: Basic authentication

Data API

FileMaker Server provides its own HTTP-based API for accessing FileMaker data:

• RESTful interface for CRUD operations
• JSON data format
• OAuth-based authentication

Status Codes

HTTP responses include status codes that indicate success or failure:

• 2xx: Success (200 OK, 201 Created, 204 No Content)
• 3xx: Redirection (301 Moved Permanently, 302 Found)
• 4xx: Client errors (400 Bad Request, 401 Unauthorized, 404 Not Found)
• 5xx: Server errors (500 Internal Server Error, 503 Service Unavailable)

Understanding these codes is crucial for robust error handling in integrations.

Best Practices

When using HTTP for data integration:

1. Use HTTPS: Always secure data in transit
2. Implement proper error handling: Check status codes and response formats
3. Set appropriate timeouts: Prevent hung scripts due to slow responses
4. Consider rate limiting: Respect API usage limits
5. Validate input/output: Always validate data before sending/after receiving
6. Use appropriate HTTP methods: Follow RESTful principles when possible