Proof-of-concept of a simple DSL for specifying servlets.

backend/api-servlets.scm

@@ -33,7 +33,10 @@
 
   (import scheme
 	  spiffy
-	  (chicken format))
+	  (chicken format)
+	  bar-db
+	  json
+	  (chicken port))
 
   (define-syntax try-match-lambda1
     (syntax-rules ()
@@ -73,8 +76,16 @@
       ((_ (name . args) . body)
        (define name (try-match-lambda args . body)))))
 
+  (define (alist->json-string alst)
+    (with-output-to-string
+      (lambda ()
+	(json-write
+	 (list->vector alst)))))
+
   (define-try-match (account-barcode-info "barcode" (barcode string->number))
-    (send-response #:body (format "API call [barcode] ~A" barcode)))
+    (send-response
+     #:body (alist->json-string
+	     `((amount . ,(bd-barcode-lookup barcode))))))
 
   (define api-servlets
     (list account-barcode-info))