🔗Interface Definition Language

NEW

Also known as: IDL

Specification language to describe interfaces and data types independent of programming languages.

DESCRIPTION

An IDL defines services, methods, messages, and data types decoupled from implementation languages. It enables code generation, compatibility checks, and stable API contracts in RPC frameworks and platform APIs. Examples include CORBA IDL, Web IDL, Apache Thrift, and Protocol Buffers schemas. Using IDLs promotes consistency across polyglot systems and eases versioning. Careful evolution and backward compatibility policies prevent breaking changes.

ALTERNATIVE DEFINITIONS

W3C

Web IDL defines a language that can be used to describe interfaces to be implemented in web browsers.

Targets browser-exposed APIs and bindings for JavaScript.

Source

Object Management Group

IDL is a specification language used to describe the interface of software components.

Focuses on language-neutral interface description for components.

Source

Apache Thrift

The Thrift IDL defines types and services in a language-neutral way.

Emphasizes language neutrality and cross-language code generation.

Source

RELATED TERMS

API gRPC Apache Thrift Web IDL CORBA JSON Schema Avro

COMPETING TERMS

OpenAPI Specification WSDL Protocol Buffers

KNOWLEDGE AREAS

Software Engineering Platform & Tooling Data Integration & Interoperability

TARGET AUDIENCE

Software Developer Software Architect Solution Architect Data Engineer

EXTERNAL SOURCES

• Wikipedia - Interface description language
• W3C - Official Web IDL specification
• OMG - CORBA IDL specification
• Apache Thrift - Thrift IDL documentation
• Protocol Buffers - Proto3 language guide

TOP QUESTIONS

What problems does Interface Definition Language solve?

IDLs create language-neutral contracts, enabling cross-language interoperability, code generation, and stable APIs.

Category: Definition

How does Interface Definition Language differ from OpenAPI?

IDLs often target binary RPC and strict schemas, while OpenAPI focuses on HTTP/JSON REST API descriptions.

Category: Opinion

What are common IDL ecosystems?

CORBA IDL, Web IDL, Apache Thrift, and Protocol Buffers are widely used in different domains.

Category: Overview

How should versioning be handled in Interface Definition Language?

Use backward-compatible changes, reserve fields, and deprecations; avoid renaming or removing required semantics.

Category: Best practices

What risks arise from evolving Interface Definition Language schemas?

Breaking changes can disrupt clients, cause serialization errors, and fragment contracts across services.

Category: Risks

How does Interface Definition Language support code generation?

Compilers produce stubs and bindings for multiple languages, reducing boilerplate and maintaining consistency.

Category: Example

Where to start with Interface Definition Language?

Choose an ecosystem (Thrift, Protobuf, Web IDL), read the spec, and generate sample clients and servers.

Category: Requirements

Is Interface Definition Language only for RPC?

Primarily, yes, but IDL concepts also apply to platform APIs and schema-driven development.

Category: Misunderstanding

How does Interface Definition Language relate to JSON Schema?

Both describe structure, but IDLs typically define services and methods; JSON Schema focuses on data validation.

Category: Comparison