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tc

Composing entities using Lisp

While it is fairly straightforward to describe entity composition using YAML, tc provides a subset of the Lisp programming language to define compositions programatically. The reason Lisp is better suited at this is because of first-class entities, s-expressions and symbolic references.

(define-event e1)


(define-event e2)


(define-function f1
    :uri "./f1"
    :runtime {:lang "python3.11"}
    :build {:kind 'inline})


(define-function f2
    :uri "./f2"
    :runtime {:lang "ruby3.3"}
    :build {:kind 'inline})


(define-function f3
    :uri "./f3"
    :runtime {:lang "clojure11.2"})


(define-route r1
    :path "/api/test"
    :async true)


(compose e1 f1 e2)


(compose r1 f1 f2 f3)

We can also use the LISP interpreter to load and eval the spec.

Terminal window
cat topology.lisp | ./tc compose --


#or


./tc repl
> (define-event e1)
> (define-event e2)
> (define-function f1 :uri "git://repo/f1.git")
> (def topology (compose f1 e1 f2))
> (print-tree topology)