parse command-line for options instead of hardcoding

note port is still hardcoded

main.fnl

@@ -36,9 +36,37 @@
 (fn slurp [filename]
   (with-open [f (io.open filename "r")] (f:read "*a")))
 
-(local ca-key (pkey.new (slurp "ca.key")))
-(local ca-crt (x509.new (slurp "ca.crt")))
-(local psk (with-open [f (io.open "psk" "r")] (f:read "l")))
+(fn read-line [filename]
+  (with-open [f (io.open filename "r")] (f:read "l")))
+
+(fn assoc [tbl k v & more]
+  (tset tbl k v)
+  (case more
+    [k v] (assoc tbl k v)
+    _ tbl))
+
+(fn parse-args [args]
+  (match args
+    ["--certificate" f & rest]
+    (assoc (parse-args rest) :certificate (slurp f))
+    ["--private-key" f & rest]
+    (assoc (parse-args rest) :private-key (slurp f))
+    ["--challenge-password" f & rest]
+    (assoc (parse-args rest) :challenge-password (read-line f))
+    [peer] { : peer }
+    _ {}))
+
+(local options
+       (doto
+           (parse-args arg)
+         (case
+             {: certificate : private-key : challenge-password : peer}
+           true
+           _
+           (assert nil "missing required command line params"))))
+
+(local ca-key (pkey.new options.private-key))
+(local ca-crt (x509.new options.certificate))
 
 (fn new-crt [csr]
   (let [crt
@@ -56,7 +84,7 @@
   (let [attr (csr:getAttributes)]
     (accumulate [found false
                  _ v (ipairs (. attr "challengePassword"))]
-      (or found (= v psk)))))
+      (or found (= v options.challenge-password)))))
 
 
 (fn handle-sign-csr [out]