From da0d2b8e6134904e84bcca5605b8e3395ab5591d Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Tue, 8 Jun 2021 09:21:54 +0200
Subject: [PATCH] attenuate-entity-ref as well as attenuate-sturdy

---
 syndicate/actor.rkt   | 9 +++++++++
 syndicate/rewrite.rkt | 1 +
 syndicate/sturdy.rkt  | 4 ++--
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/syndicate/actor.rkt b/syndicate/actor.rkt
index 63cff90..e20b9f7 100644
--- a/syndicate/actor.rkt
+++ b/syndicate/actor.rkt
@@ -6,6 +6,7 @@
          (rename-out [make-entity entity])
 
          (struct-out entity-ref)
+         attenuate-entity-ref
          parse-Ref
          Ref->preserves
 
@@ -432,3 +433,11 @@
 (define (deliver maybe-proc . args)
   (when maybe-proc
     (apply maybe-proc args)))
+
+;; TODO: prove to myself I've gotten the order correct. (Right-to-left, wasn't it?!?!)
+(define (attenuate-entity-ref r . caveats)
+  (if (null? caveats)
+      r
+      (match r
+        [(entity-ref relay target previous-attenuation)
+         (entity-ref relay target (append previous-attenuation caveats))])))
diff --git a/syndicate/rewrite.rkt b/syndicate/rewrite.rkt
index 0519232..3c163d8 100644
--- a/syndicate/rewrite.rkt
+++ b/syndicate/rewrite.rkt
@@ -90,6 +90,7 @@
     [(Caveat-Rewrite r)
      (rewrite r v)]))
 
+;; TODO: prove to myself I've gotten the order correct. (Right-to-left, wasn't it?!?!)
 (define (run-rewrites attenuation v)
   (let loop ((stages attenuation) (v v))
     (match stages
diff --git a/syndicate/sturdy.rkt b/syndicate/sturdy.rkt
index b0fabfa..c0b9759 100644
--- a/syndicate/sturdy.rkt
+++ b/syndicate/sturdy.rkt
@@ -15,7 +15,7 @@
          sturdy-encode
          sturdy-decode
          mint
-         attenuate
+         attenuate-sturdy
          SturdyRef-valid?
          validate
          (all-from-out "schemas/gen/sturdy.rkt"))
@@ -47,7 +47,7 @@
 (define (mint oid key)
   (SturdyRef oid '() (hmac-sha256 key (sturdy-encode oid))))
 
-(define (attenuate r . attenuation)
+(define (attenuate-sturdy r . attenuation)
   (match-define (SturdyRef oid caveatChain sig) r)
   (SturdyRef oid
              (append caveatChain (list attenuation))