roller: add get-pending-tx rpc from l2 tx hash

pkg/arvo/app/roller-rpc.hoon

@@ -161,6 +161,7 @@
       %get-all-pending         `(all:pending id +.params all:pending:scry)
       %get-pending-by-ship     `(ship:pending id +.params ship:pending:scry)
       %get-pending-by-address  `(addr:pending id +.params addr:pending:scry)
+      %get-pending-tx          `(hash:pending id +.params hash:pending:scry)
       %get-transaction-status  `(status id +.params tx-status:scry)
       %when-next-batch         `(next-batch id +.params next-batch:scry)
       %get-nonce               `(nonce id +.params nonce:scry)
@@ -258,6 +259,14 @@
           %+  ~(scry agentio bowl)  %roller
           /pending/[(scot %ux address)]/noun
       ==
+    ::
+    ++  hash
+      |=  keccak=@ux
+      .^  (unit pend-tx)
+          %gx
+          %+  ~(scry agentio bowl)  %roller
+          /pending-tx/[(scot %ux keccak)]/noun
+      ==
     --
   ::
   ++  history

pkg/arvo/app/roller.hoon

@@ -174,6 +174,7 @@
       [%x %pending ~]       ``noun+!>(pending)
       [%x %pending @ ~]     (pending-by i.t.t.path)
       [%x %tx @ %status ~]  (status i.t.t.path)
+      [%x %pending-tx @ ~]  (transaction i.t.t.path)
       [%x %history @ ~]     (history i.t.t.path)
       [%x %nonce @ @ ~]     (nonce i.t.t.path i.t.t.t.path)
       [%x %spawned @ ~]     (spawned i.t.t.path)
@@ -221,13 +222,29 @@
       ?^  status=(~(get by finding) u.keccak)
         ?@  u.status  [u.status ~]
         [%sending `+.u.status]
-      ::TODO  potentially slow!
+      :: TODO: potentially slow!
+      :: TODO: use ~(get by history) instead
       =;  known=?
         [?:(known %pending %unknown) ~]
       %+  lien  pending
       |=  pend-tx
       =(u.keccak (hash-tx:lib raw.raw-tx))
     ::
+    ++  transaction
+      |=  wat=@t
+      ?~  keccak=(slaw %ux wat)
+        [~ ~]
+      :+  ~  ~
+      :-  %noun
+      !>  ^-  (unit pend-tx)
+      :: TODO: potentially slow!
+      |-
+      ?~  pending  ~
+      =*  tx  i.pending
+      ?:  =(u.keccak (hash-tx:lib raw.raw-tx.tx))
+        `tx
+      $(pending t.pending)
+    ::
     ++  history
       |=  wat=@t
       :+  ~  ~

pkg/arvo/lib/azimuth-roll-rpc.hoon

@@ -184,11 +184,7 @@
     ++  to-json
       =,  enjs:format
       |%
-      ++  pending
+      ++  pending-tx
-        |=  pending=(list pend-tx)
-        ^-  json
-        :-  %a
-        %+  turn  pending
         |=  pend-tx
         ^-  json
         %-  pairs
@@ -201,6 +197,11 @@
                 ['sig' (hex (as-octs:mimes:html sig.raw-tx))]
         ==  ==
       ::
+      ++  pending-txs
+        |=  pending=(list pend-tx)
+        ^-  json
+        a+(turn pending pending-tx)
+      ::
       ++  en-address   |=(a=@ux address+(hex 20 a))
       ::
       ++  tx
@@ -524,7 +525,7 @@
     ^-  response:rpc
     ?.  =((lent ~(tap by params)) 0)
       ~(params error:json-rpc id)
-    [%result id (pending:to-json pending)]
+    [%result id (pending-txs:to-json pending)]
   ::
   ++  ship
     |=  [id=@t params=(map @t json) scry=$-(@p (list pend-tx))]
@@ -533,7 +534,7 @@
       ~(params error:json-rpc id)
     ?~  ship=(ship:from-json params)
       ~(parse error:json-rpc id)
-    [%result id (pending:to-json (scry u.ship))]
+    [%result id (pending-txs:to-json (scry u.ship))]
   ::
   ++  addr
     |=  [id=@t params=(map @t json) scry=$-(@ux (list pend-tx))]
@@ -542,7 +543,18 @@
       ~(params error:json-rpc id)
     ?~  address=(address:from-json params)
       ~(parse error:json-rpc id)
-    [%result id (pending:to-json (scry u.address))]
+    [%result id (pending-txs:to-json (scry u.address))]
+  ::
+  ++  hash
+    |=  [id=@t params=(map @t json) scry=$-(@ux (unit pend-tx))]
+    ^-  response:rpc
+    ?.  =((lent ~(tap by params)) 1)
+      ~(params error:json-rpc id)
+    ?~  hash=(hash:from-json params)
+      ~(parse error:json-rpc id)
+    ?~  tx=(scry u.hash)
+      ~(not-found error:json-rpc id)
+    [%result id (pending-tx:to-json u.tx)]
   --
 ::
 ++  status