Technology Mappings (Endpoint Level)

Note: This page contains incomplete, informal mappings. It is not part of the MDSL language specification, but intended to serves as background information for instance when working with the generator [tools]./tools).

RESTful HTTP (a.k.a. HTTP resource APIs)

Endpoints correspond to resources (with the mapping not being straightforward due to concepts such as URI templates and path parameters in HTTP). Operations correspond to HTTP verbs or methods (with additional constraints being imposed by the architectural style and nest practices for REST).

Web Services Description Language (WSDL)

MDSL endpoints map to port types in WSDL; operations (not surprisingly) to operations. API providers are pendants to ports in WSDL, API clients are service consumers.

Jolie

The service contract grammar can easily be mapped to the glossary of Jolie terms. For instance, endpoint types in MDSL correspond to interfaces in Jolie:

Jolie	MDSL/MAP	Comments
Operation	Operation	n/a
Interface	Endpoint type	n/a
tbd	API (multiple endpoint types)	n/a
Port (inbound)	API provider	n/a
Port (outbound)	API client	n/a
(Micro-)Service	(Micro-)Service	exposes one or more APIs with one or more operations
Conversation	Conversation	to be checked
Service definition	(service implementation)	n/a
Service network	tbd	n/a
Cell and related concepts	not in scope	n/a

gRPC and Protocol Buffers

An endpoint type in MDSL corresponds to a gRPC service; MDSL operations correspond to gRPC messages.

Other integration technologies

MSDL service contracts can also be mapped to GraphQL, and Avro in a straightforward manner. Stay tuned!

Technology Mappings (Data Contract Level)

JSON/JSON Schema

JSON	MDSL	Comments
Basic JSON data types	Atomic Parameter	Base types do not match 100%
Object (flat)	Parameter Tree (flat) or Atomic Parameter List	Parameter Tree preferred
Object (structured)	Parameter Tree (nested)	Straightforward
Array	Cardinality of * or +	Is homogeneous in MDSL/MAP

XML Schema

XML Schema	MDSL/MAP	Comments
Built-in data types	Atomic Parameter	Not the same expressiveness
Sequence element (referencing built-in types)	Parameter Tree (flat) or Atomic Parameter List	Parameter Tree preferred
Complex type	Parameter Tree	MDSL syntax more compact
Sequence with maxoccurs > 1	Cardinality of * or +	n/a

gRPC and Protocol Buffers

The MAP base types can be mapped in a straightforward manner. AnyType is used as default.

Parameter forests and parameter trees translate into nested messages.

Jolie

The MAP base types map to simple data in Jolie in a straightforward manner.

The same holds for the mapping of parameter trees to Jolie data structures.

An example can be downloaded here.