rename http-fstree => json-to-fstree

it works for file urls as well, not just http

pkgs/json-to-fstree/default.nix

@@ -0,0 +1,37 @@
+{
+  fetchurl,
+  writeFennel,
+  fennel,
+  fennelrepl,
+  runCommand,
+  lua,
+  anoia,
+  linotify,
+  lualinux,
+  fetch-freebsd,
+  openssl,
+  rxi-json,
+  stdenv
+}:
+let name = "json-to-fstree";
+in stdenv.mkDerivation {
+  inherit name;
+  src = ./.;
+
+  buildInputs = [fetch-freebsd rxi-json openssl lua];
+
+  buildPhase = "";
+  installPhase = ''
+    mkdir -p $out/bin
+    cp -p ${writeFennel name {
+      packages = [
+        fetch-freebsd
+        rxi-json
+        anoia
+        lualinux
+        linotify
+      ] ;
+      mainFunction = "run";
+    } ./${name}.fnl } $out/bin/${name}
+  '';
+}

pkgs/json-to-fstree/json-to-fstree.fnl

@@ -0,0 +1,24 @@
+(local json (require :json))
+(local http (require :fetch))
+(local svc (require :anoia.svc))
+(local { : utime } (require :lualinux))
+
+(fn download [url dest]
+  (match (http.fetch url)
+    (nil code str)
+    (assert nil (.. "error " code ": " str))
+
+    (body { : last-modified })
+    (let [service (svc.open dest)
+          lock (.. dest "/.lock")
+          state (.. dest "/state")]
+      (with-open [fout (io.open lock :w)] (fout:write ""))
+      (service:output "." (json.decode body))
+      (with-open [fout (io.open state :w)] (fout:write "ok"))
+      (os.remove lock)
+      (utime dest last-modified))))
+
+(fn run [] (download (. arg 1) (. arg 2)))
+
+
+{ : run }