Make a proper default.nix, cleanup lockfile

Update syndicate dependency
Add http_client
2024-05-10 12:08:51 +02:00 · 2024-05-09 18:31:20 +02:00 · 2024-05-09 18:31:20 +02:00 · 2024-04-30 13:56:48 +02:00 · 2024-04-23 10:25:03 +02:00 · 2024-04-09 10:14:58 +01:00
27 changed files with 479 additions and 336 deletions
--- a/README.md
+++ b/README.md
@ -47,6 +47,46 @@ Query the size of a directory in bytes by observing `<file-system-usage "/SOME/P
 ]
 ```

+### HTTP driver
+
+Experimental HTTP server that services requests using [some version](https://git.syndicate-lang.org/syndicate-lang/syndicate-protocols/src/commit/9864ce0ec86fb2f916c2aab318a1e6994ab8834c/schemas/http.prs) of the http Syndicate protocol schema.
+
+```
+# Configuration example
+
+let ?not-found = dataspace
+$not-found ? <request _ ?res> [
+  $res ! <status 503 "Service unavailable">
+  $res ! <done "No binding here.">
+]
+
+let ?greeting = dataspace
+$greeting ? <request _ ?res> [
+  $res ! <status 200 "ok">
+  $res ! <chunk "Hello world">
+  $res ! <done "!">
+]
+
+let ?http = dataspace
+$http [
+  <http-bind #f 80 get [ ] $not-found>
+  <http-bind #f 80 get [|...|] $not-found>
+  <http-bind #f 80 get ["hello"] $greeting>
+]
+
+? <service-object <daemon http-driver> ?cap> [
+  $cap <http-driver { dataspace: $http }>
+]
+
+<daemon http-driver {
+  argv: [ "/bin/syndesizer" ]
+  clearEnv: #t
+  protocol: application/syndicate
+}>
+
+<require-service <daemon http-driver>>
+```
+
 ### JSON Socket Translator

 Communicate with sockets that send and receive lines of JSON using `<send …>` and `<recv …>` messages.
@ -168,8 +208,13 @@ let ?tuplespace = dataspace

 $sqlspace <query "SELECT id, name FROM stuff" $tuplespace>

-$tuplespace ? [?id ?name] [
-  $log ! <log "-" { row: <example-row $id $name> }>
+$tuplespace [
+  ? [?id ?name] [
+    $log ! <log "-" { row: <example-row $id $name> }>
+  ]
+  ? <sqlite-error ?msg ?ctx> [
+    $log ! <log "-" { msg: $msg ctx: $ctx }>
+  ]
 ]
 ```

@ -196,6 +241,63 @@ Examples:

 ---

+## http_client
+
+The inverse of `http-driver`.
+
+### Caveats
+- HTTPS is assumed unless the request is to port 80.
+- If the request or response sets `Content-Type` to `application/json` or `…/preserves`
+  the body will be a parsed Preserves value.
+- No cache support.
+- Internal errors propagate using a `400 Internal client error` response.
+
+Sample Syndicate server script:
+```
+# A top-level dataspace
+let ?ds = dataspace
+
+# A dataspace for handling the HTTP response.
+let ?response = dataspace
+$response [
+  ?? <done { "code": "EUR" "exchange_middle": ?middle } > [
+    $ds <exchange EUR RSD $middle>
+  ]
+]
+
+$ds [
+  <request
+      # Request Euro to Dinar exchange rate.
+      <http-request 0 "kurs.resenje.org" 443
+        get ["api" "v1" "currencies" "eur" "rates" "today"]
+        {Content-Type: "application/json"} {} #f
+      >
+    $response
+  >
+
+  # Log all assertions.
+  ? ?any [
+    $log ! <log "-" { assertion: $any }>
+  ]
+]
+
+? <service-object <daemon http-client> ?cap> [
+  $cap <http-client {
+    dataspace: $ds
+  }>
+]
+
+<require-service <daemon http-client>>
+
+? <built http-client ?path ?sum> [
+  <daemon http-client {
+    argv: [ "/bin/http_client" ]
+    clearEnv: #t
+    protocol: application/syndicate
+  }>
+]
+```
+
 ## mintsturdyref

 A utility for minting [Sturdyrefs](https://synit.org/book/operation/builtin/gatekeeper.html#sturdyrefs).
--- a/config.prs
+++ b/config.prs
@ -26,6 +26,10 @@ UnixAddress = <unix @path string>.

 SocketAddress = TcpAddress / UnixAddress .

+HttpClientArguments = <http-client {
+  dataspace: #:any
+}>.
+
 HttpDriverArguments = <http-driver {
  dataspace: #:any
 }>.
--- a/default.nix
+++ b/default.nix
@ -0,0 +1,34 @@
+{
+  pkgs ? import <nixpkgs> { },
+}:
+
+let
+  inherit (pkgs)
+    lib
+    buildNimPackage
+    fetchFromGitea
+    libxml2
+    libxslt
+    openssl
+    pkg-config
+    postgresql
+    sqlite
+    ;
+in
+
+buildNimPackage {
+  pname = "syndicate_utils";
+  version = "unstable";
+
+  src = if lib.inNixShell then null else lib.cleanSource ./.;
+
+  buildInputs = [
+    postgresql.out
+    sqlite
+    libxml2
+    libxslt
+    openssl
+  ];
+
+  lockFile = ./lock.json;
+}
--- a/lock.json
+++ b/lock.json
@ -1,16 +1,5 @@
 {
  "depends": [
-    {
-      "method": "fetchzip",
-      "packages": [
-        "bigints"
-      ],
-      "path": "/nix/store/jvrm392g8adfsgf36prgwkbyd7vh5jsw-source",
-      "rev": "86ea14d31eea9275e1408ca34e6bfe9c99989a96",
-      "sha256": "15pcpmnk1bnw3k8769rjzcpg00nahyrypwbxs88jnwr4aczp99j4",
-      "srcDir": "src",
-      "url": "https://github.com/ehmry/nim-bigints/archive/86ea14d31eea9275e1408ca34e6bfe9c99989a96.tar.gz"
-    },
    {
      "method": "fetchzip",
      "packages": [
@ -22,28 +11,6 @@
      "srcDir": "",
      "url": "https://github.com/ehmry/cps/archive/c90530ac57f98a842b7be969115c6ef08bdcc564.tar.gz"
    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "cps"
-      ],
-      "path": "/nix/store/8gbhwni0akqskdb3qhn5nfgv6gkdz0vz-source",
-      "rev": "c90530ac57f98a842b7be969115c6ef08bdcc564",
-      "sha256": "0h8ghs2fqg68j3jdcg7grnxssmllmgg99kym2w0a3vlwca1zvr62",
-      "srcDir": "",
-      "url": "https://github.com/ehmry/cps/archive/c90530ac57f98a842b7be969115c6ef08bdcc564.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "getdns"
-      ],
-      "path": "/nix/store/x9xmn7w4k6jg8nv5bnx148ibhnsfh362-source",
-      "rev": "c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6",
-      "sha256": "1sbgx2x51szr22i72n7c8jglnfmr8m7y7ga0v85d58fwadiv7g6b",
-      "srcDir": "src",
-      "url": "https://git.sr.ht/~ehmry/getdns-nim/archive/c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6.tar.gz"
-    },
    {
      "method": "fetchzip",
      "packages": [
@ -71,11 +38,11 @@
      "packages": [
        "preserves"
      ],
-      "path": "/nix/store/2hy124xgabz134dxj3wji7mp47fdwy3w-source",
-      "rev": "9ae435a83c6d5028405538af5d24a023af625b6e",
-      "sha256": "1k7ywcp1a53x2fpc6wc2b0qzb264dkifash0s1wcp66rw3lx15k2",
+      "path": "/nix/store/hzb7af7lbd4kgd5y4hbgxv1lswig36yj-source",
+      "rev": "fd498c6457cb9ad2f3179daa40da69eec00326dd",
+      "sha256": "182xvw04vjw83mlcrkwkip29b44h0v8dapg2014k9011h90mdsj4",
      "srcDir": "src",
-      "url": "https://git.syndicate-lang.org/ehmry/preserves-nim/archive/9ae435a83c6d5028405538af5d24a023af625b6e.tar.gz"
+      "url": "https://git.syndicate-lang.org/ehmry/preserves-nim/archive/fd498c6457cb9ad2f3179daa40da69eec00326dd.tar.gz"
    },
    {
      "method": "fetchzip",
@ -93,11 +60,11 @@
      "packages": [
        "syndicate"
      ],
-      "path": "/nix/store/kl628g7vg2ww8wilf8h2ag7qqnvvwdzb-source",
-      "rev": "c2e1e2e0fa403529750196ce3ccb5a99a4d6c006",
-      "sha256": "1r8ab79pgrrnzmp49h8rp50c9x8zd0p7bsvzxaphc221nvyfx09j",
+      "path": "/nix/store/dw30cq9gxz3353zgaq4a36ajq6chvbwc-source",
+      "rev": "3a4dc1f13392830b587138199643d30fdbec8541",
+      "sha256": "1mbd17rjm1fsx7d0ckzyjih2nzdjqs52ck9wscqcg9nvf3ib5mvh",
      "srcDir": "src",
-      "url": "https://git.syndicate-lang.org/ehmry/syndicate-nim/archive/c2e1e2e0fa403529750196ce3ccb5a99a4d6c006.tar.gz"
+      "url": "https://git.syndicate-lang.org/ehmry/syndicate-nim/archive/3a4dc1f13392830b587138199643d30fdbec8541.tar.gz"
    },
    {
      "method": "fetchzip",
@ -110,39 +77,6 @@
      "srcDir": "src",
      "url": "https://github.com/ehmry/nim-sys/archive/4ef3b624db86e331ba334e705c1aa235d55b05e1.tar.gz"
    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "sys"
-      ],
-      "path": "/nix/store/syhxsjlsdqfap0hk4qp3s6kayk8cqknd-source",
-      "rev": "4ef3b624db86e331ba334e705c1aa235d55b05e1",
-      "sha256": "1q4qgw4an4mmmcbx48l6xk1jig1vc8p9cq9dbx39kpnb0890j32q",
-      "srcDir": "src",
-      "url": "https://github.com/ehmry/nim-sys/archive/4ef3b624db86e331ba334e705c1aa235d55b05e1.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "sys"
-      ],
-      "path": "/nix/store/vf9ls2wip6d8xhsi3rjh0dqsqg597i6b-source",
-      "rev": "c117ee60542f084525f254e6ade590675a6a2ed6",
-      "sha256": "12qzx2lnh84xqfgypy0pka8nflq0y8n1izfwx8mb4zya5nzawmyf",
-      "srcDir": "src",
-      "url": "https://github.com/alaviss/nim-sys/archive/c117ee60542f084525f254e6ade590675a6a2ed6.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "taps"
-      ],
-      "path": "/nix/store/6y14ia52kr7jyaa0izx37mlablmq9s65-source",
-      "rev": "8c8572cd971d1283e6621006b310993c632da247",
-      "sha256": "1dp166bv9x773jmfqppg5i3v3rilgff013vb11yzwcid9l7s3iy8",
-      "srcDir": "src",
-      "url": "https://git.sr.ht/~ehmry/nim_taps/archive/8c8572cd971d1283e6621006b310993c632da247.tar.gz"
-    },
    {
      "method": "fetchzip",
      "packages": [
@ -174,35 +108,24 @@
    {
      "method": "fetchzip",
      "packages": [
-        "getdns"
+        "bigints"
      ],
-      "path": "/nix/store/x9xmn7w4k6jg8nv5bnx148ibhnsfh362-source",
-      "rev": "c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6",
-      "sha256": "1sbgx2x51szr22i72n7c8jglnfmr8m7y7ga0v85d58fwadiv7g6b",
+      "path": "/nix/store/jvrm392g8adfsgf36prgwkbyd7vh5jsw-source",
+      "rev": "86ea14d31eea9275e1408ca34e6bfe9c99989a96",
+      "sha256": "15pcpmnk1bnw3k8769rjzcpg00nahyrypwbxs88jnwr4aczp99j4",
      "srcDir": "src",
-      "url": "https://git.sr.ht/~ehmry/getdns-nim/archive/c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "getdns"
-      ],
-      "path": "/nix/store/x9xmn7w4k6jg8nv5bnx148ibhnsfh362-source",
-      "rev": "c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6",
-      "sha256": "1sbgx2x51szr22i72n7c8jglnfmr8m7y7ga0v85d58fwadiv7g6b",
-      "srcDir": "src",
-      "url": "https://git.sr.ht/~ehmry/getdns-nim/archive/c73cbe288d9f9480586b8fa87f6d794ffb6a6ce6.tar.gz"
+      "url": "https://github.com/ehmry/nim-bigints/archive/86ea14d31eea9275e1408ca34e6bfe9c99989a96.tar.gz"
    },
    {
      "method": "fetchzip",
      "packages": [
        "nimcrypto"
      ],
-      "path": "/nix/store/fkrcpp8lzj2yi21na79xm63xk0ggnqsp-source",
-      "rev": "f147d30c69bc1c9bcf0e37f7699bcf0fbaab97b5",
-      "sha256": "1h3dzdbc9kacwpi10mj73yjglvn7kbizj1x8qc9099ax091cj5xn",
+      "path": "/nix/store/h7lgq3by9mx8in03vzh0y964lnnlkalp-source",
+      "rev": "ff6afc6a753bd645cad4568472c7733d1715e31e",
+      "sha256": "0h9vpayp66pg66114bl0nsvlv1nzp7f0x5b35gbsbd7svzlcz5zj",
      "srcDir": "",
-      "url": "https://github.com/cheatfate/nimcrypto/archive/f147d30c69bc1c9bcf0e37f7699bcf0fbaab97b5.tar.gz"
+      "url": "https://github.com/cheatfate/nimcrypto/archive/ff6afc6a753bd645cad4568472c7733d1715e31e.tar.gz"
    },
    {
      "method": "fetchzip",
@ -214,89 +137,6 @@
      "sha256": "1fi9ls3xl20bmv1ikillxywl96i9al6zmmxrbffx448gbrxs86kg",
      "srcDir": "src",
      "url": "https://github.com/zevv/npeg/archive/ec0cc6e64ea4c62d2aa382b176a4838474238f8d.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "stew"
-      ],
-      "path": "/nix/store/mqg8qzsbcc8xqabq2yzvlhvcyqypk72c-source",
-      "rev": "3c91b8694e15137a81ec7db37c6c58194ec94a6a",
-      "sha256": "17lfhfxp5nxvld78xa83p258y80ks5jb4n53152cdr57xk86y07w",
-      "srcDir": "",
-      "url": "https://github.com/status-im/nim-stew/archive/3c91b8694e15137a81ec7db37c6c58194ec94a6a.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "sys"
-      ],
-      "path": "/nix/store/vf9ls2wip6d8xhsi3rjh0dqsqg597i6b-source",
-      "rev": "c117ee60542f084525f254e6ade590675a6a2ed6",
-      "sha256": "12qzx2lnh84xqfgypy0pka8nflq0y8n1izfwx8mb4zya5nzawmyf",
-      "srcDir": "src",
-      "url": "https://github.com/alaviss/nim-sys/archive/c117ee60542f084525f254e6ade590675a6a2ed6.tar.gz"
-    },
-    {
-      "date": "2024-04-02T15:38:57+01:00",
-      "deepClone": false,
-      "fetchLFS": false,
-      "fetchSubmodules": true,
-      "hash": "sha256-iZb9aAgYr4FGkqfIg49QWiCqeizIi047kFhugHiP8o0=",
-      "leaveDotGit": false,
-      "method": "git",
-      "packages": [
-        "solo5_dispatcher"
-      ],
-      "path": "/nix/store/sf5dgj2ljvahcm6my7d61ibda51vnrii-solo5_dispatcher",
-      "rev": "a7a894a96a2221284012800e6fd32923d83d20bd",
-      "sha256": "13gjixw80vjqj0xlx2y85ixal82sa27q7j57j9383bqq11lgv5l9",
-      "srcDir": "pkg",
-      "url": "https://git.sr.ht/~ehmry/solo5_dispatcher"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "cps"
-      ],
-      "path": "/nix/store/phdf6siqbhj7vx4qq507lzla81si60iz-source",
-      "rev": "58772ff9ddb38a4b2ec52da142d8532ba2fe7039",
-      "sha256": "1lph7v27nqwgm3a0ssi8q348gjrkjwgqc50agw38j7xif6wj80cw",
-      "srcDir": "",
-      "url": "https://github.com/ehmry/cps/archive/58772ff9ddb38a4b2ec52da142d8532ba2fe7039.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "cps"
-      ],
-      "path": "/nix/store/phdf6siqbhj7vx4qq507lzla81si60iz-source",
-      "rev": "58772ff9ddb38a4b2ec52da142d8532ba2fe7039",
-      "sha256": "1lph7v27nqwgm3a0ssi8q348gjrkjwgqc50agw38j7xif6wj80cw",
-      "srcDir": "",
-      "url": "https://github.com/ehmry/cps/archive/58772ff9ddb38a4b2ec52da142d8532ba2fe7039.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "stew"
-      ],
-      "path": "/nix/store/mqg8qzsbcc8xqabq2yzvlhvcyqypk72c-source",
-      "rev": "3c91b8694e15137a81ec7db37c6c58194ec94a6a",
-      "sha256": "17lfhfxp5nxvld78xa83p258y80ks5jb4n53152cdr57xk86y07w",
-      "srcDir": "",
-      "url": "https://github.com/status-im/nim-stew/archive/3c91b8694e15137a81ec7db37c6c58194ec94a6a.tar.gz"
-    },
-    {
-      "method": "fetchzip",
-      "packages": [
-        "stew"
-      ],
-      "path": "/nix/store/mqg8qzsbcc8xqabq2yzvlhvcyqypk72c-source",
-      "rev": "3c91b8694e15137a81ec7db37c6c58194ec94a6a",
-      "sha256": "17lfhfxp5nxvld78xa83p258y80ks5jb4n53152cdr57xk86y07w",
-      "srcDir": "",
-      "url": "https://github.com/status-im/nim-stew/archive/3c91b8694e15137a81ec7db37c6c58194ec94a6a.tar.gz"
    }
  ]
 }
--- a/shell.nix
+++ b/shell.nix
@ -1,11 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-pkgs.buildNimPackage {
-  name = "syndicate_utils";
-  propagatedNativeBuildInputs =
-    builtins.attrValues { inherit (pkgs) pkg-config solo5; };
-  propagatedBuildInputs = builtins.attrValues {
-    inherit (pkgs) getdns postgresql solo5 sqlite libxml2 libxslt;
-  };
-  lockFile = ./lock.json;
-}
--- a/sql.prs
+++ b/sql.prs
@ -2,4 +2,7 @@ version 1 .

 # When asserted the actor reponds to @target rows as records
 # of the given label and row columns as record fields.
-Query = <query @statement string @target #:any> .
+Query = <query @statement [any ...] @target #:any> .
+
+# When a query fails this is asserted instead.
+SqlError = <sql-error @msg string @context string>.
--- a/src/http_client.nim
+++ b/src/http_client.nim
@ -0,0 +1,91 @@
+# SPDX-FileCopyrightText: ☭ Emery Hemingway
+# SPDX-License-Identifier: Unlicense
+
+# TODO: write a TAPS HTTP client. Figure out how to externalise TLS.
+
+import
+  std/[httpclient, options, streams, strutils, tables, uri],
+  pkg/taps,
+  pkg/preserves,
+  pkg/syndicate, pkg/syndicate/protocols/http,
+  ./schema/config
+
+proc url(req: HttpRequest): Uri =
+  result.scheme = if req.port == 80: "http" else: "https"
+  result.hostname = req.host.present
+  result.port = $req.port
+  for i, p in req.path:
+    if 0 < i: result.path.add '/'
+    result.path.add p.encodeUrl
+  for key, vals in req.query:
+    if result.query.len > 0:
+      result.query.add '&'
+    result.query.add key.string.encodeUrl
+    for i, val in vals:
+      if i == 0: result.query.add '='
+      elif i < vals.high: result.query.add ','
+      result.query.add val.string.encodeUrl
+
+proc bodyString(req: HttpRequest): string =
+  if req.body.orKind == RequestBodyKind.present:
+    return cast[string](req.body.present)
+
+proc spawnHttpClient*(turn: Turn; root: Cap): Actor {.discardable.} =
+
+  during(turn, root, ?:HttpClientArguments) do (ds: Cap):
+    spawn("http-client", turn) do (turn: Turn):
+      during(turn, ds, HttpContext.grabType) do (ctx: HttpContext):
+        let peer = ctx.res.unembed(Cap).get
+        var client = newHttpClient()
+        try:
+          var
+            headers = newHttpHeaders()
+            contentType = ""
+          for key, val in ctx.req.headers:
+            if key == Symbol"Content-Type":
+              contentType = val
+            client.headers[key.string] = val
+          let stdRes = client.request(
+              ctx.req.url,
+              ctx.req.method.string.toUpper,
+              ctx.req.bodyString, headers
+            )
+          var resp = HttpResponse(orKind: HttpResponseKind.status)
+          resp.status.code = stdRes.status[0 .. 2].parseInt
+          resp.status.message = stdRes.status[3 .. ^1]
+          message(turn, peer, resp)
+          resp = HttpResponse(orKind: HttpResponseKind.header)
+          for key, val in stdRes.headers:
+            if key == "Content-Type":
+              contentType = val
+            resp.header.name = key.Symbol
+            resp.header.value = val
+          message(turn, peer, resp)
+          case contentType
+          of "application/json", "text/preserves":
+            message(turn, peer,
+                initRecord("done", stdRes.bodyStream.readAll.parsePreserves))
+          of "application/preserves":
+            message(turn, peer,
+                initRecord("done", stdRes.bodyStream.decodePreserves))
+          else:
+            resp = HttpResponse(orKind: HttpResponseKind.done)
+            resp.done.chunk.string = stdRes.bodyStream.readAll()
+            message(turn, peer, resp)
+        except CatchableError as err:
+          var resp = HttpResponse(orKind: HttpResponseKind.status)
+          resp.status.code = 400
+          resp.status.message = "Internal client error"
+          message(turn, peer, resp)
+          resp = HttpResponse(orKind: HttpResponseKind.done)
+          resp.done.chunk.string = err.msg
+          message(turn, peer, resp)
+        client.close()
+      do:
+        client.close()
+
+when isMainModule:
+  import syndicate/relays
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
+      spawnHttpClient(turn, ds)
--- a/src/http_client.nim.cfg
+++ b/src/http_client.nim.cfg
@ -0,0 +1 @@
+define:ssl
--- a/src/mount_actor.nim
+++ b/src/mount_actor.nim
@ -7,7 +7,7 @@ when not defined(linux):
  {.error: "this component only tested for Linux".}

 import std/oserrors
-import preserves
+import preserves, preserves/sugar
 import syndicate
 import ./schema/mountpoints

@ -20,11 +20,14 @@ proc mount(source, target, fsType: cstring; flags: culong; data: pointer): cint
 proc umount(target: cstring): cint {.importc, header: "<sys/mount.h>".}
  ## `umount(2)`

-proc spawnMountActor*(turn: var Turn; ds: Cap): Actor {.discardable.} =
-  spawnActor(turn, "mount_actor") do (turn: var Turn):
+proc spawnMountActor*(turn: Turn; ds: Cap): Actor {.discardable.} =
+  spawnActor(turn, "mount_actor") do (turn: Turn):
    let
-      targetPat = ?Observe(pattern: !Mountpoint) ?? { 1: grabLit() }
-      sourcePat = ?Observe(pattern: !Mountpoint) ?? { 0: grabLit(), 2: grabLit() }
+      targetPat = observePattern(!Mountpoint, { @[%1]: grabLit() })
+      sourcePat = observePattern(!Mountpoint, {
+          @[%0]: grabLit(),
+          @[%2]: grabLit(),
+        })
    during(turn, ds, ?:BootArgs) do (ds: Cap):
      during(turn, ds, targetPat) do (target: string):
        during(turn, ds, sourcePat) do (source: string, fsType: string):
@ -45,6 +48,6 @@ proc spawnMountActor*(turn: var Turn; ds: Cap): Actor {.discardable.} =

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      discard spawnMountActor(turn, ds)
--- a/src/msg.nim
+++ b/src/msg.nim
@ -6,11 +6,11 @@ import preserves, syndicate, syndicate/relays

 setControlCHook(proc () {.noconv.} = quit())

-runActor("msg") do (turn: var Turn):
+runActor("msg") do (turn: Turn):
  let
    data = map(commandLineParams(), parsePreserves)
    cmd = paramStr(0).extractFilename.normalize
-  resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  resolveEnvironment(turn) do (turn: Turn; ds: Cap):
    case cmd
    of "assert":
      for e in data:
@ -18,5 +18,5 @@ runActor("msg") do (turn: var Turn):
    else: # "msg"
      for e in data:
        message(turn, ds, e)
-      sync(turn, ds) do (turn: var Turn):
+      sync(turn, ds) do (turn: Turn):
        stopActor(turn)
--- a/src/postgre_actor.nim
+++ b/src/postgre_actor.nim
@ -87,8 +87,26 @@ proc splitParams(params: StringPairs): (cstringArray, cstringArray) =
  for i, _ in params: strings[i] = params[i][1]
  result[1] = allocCStringArray(strings)

-proc spawnPostgreActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawn("postgre", turn) do (turn: var Turn):
+proc renderSql(tokens: openarray[Value]): string =
+  for token in tokens:
+    if result.len > 0: result.add ' '
+    case token.kind
+    of pkSymbol:
+      result.add token.symbol.string
+    of pkString:
+      result.add '\''
+      result.add token.string
+      result.add '\''
+    of pkFloat, pkRegister, pkBigInt:
+      result.add $token
+    of pkBoolean:
+      if token.bool: result.add '1'
+      else: result.add '0'
+    else:
+      return ""
+
+proc spawnPostgreActor*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawn("postgre", turn) do (turn: Turn):
    during(turn, root, ?:PostgreArguments) do (params: StringPairs, ds: Cap):
      var
        conn: PGconn
@ -102,21 +120,29 @@ proc spawnPostgreActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
      statusHandle = publish(turn, ds,
          initRecord("status", toSymbol($status), msg.toPreserves))
      if status == CONNECTION_OK:
-        during(turn, ds, ?:Query) do (statement: string, target: Cap):
-          var res = PQexec(conn, statement)
-          var st = PQresultStatus(res)
-          discard publish(turn, ds, toRecord(
-            "error", statement, toSymbol($PQresStatus(st)), $PQresultErrorMessage(res)))
-          if st == PGRES_TUPLES_OK or st == PGRES_SINGLE_TUPLE:
-            let tuples = PQntuples(res)
-            let fields = PQnfields(res)
-            if tuples > 0 and fields > 0:
-              for r in 0..<tuples:
-                var tupl = initSequence(fields)
-                for f in 0..<fields:
-                  tupl[f] = toPreserves($PQgetvalue(res, r, f))
-                discard publish(turn, target, tupl)
-          PQclear(res)
+        during(turn, ds, ?:Query) do (statement: seq[Value], target: Cap):
+          var text = renderSql statement
+          if text == "":
+            discard publish(turn, ds, SqlError(msg: "invalid statement", context: $statement))
+          else:
+            var
+              res = PQexec(conn, text)
+              st = PQresultStatus(res)
+            if st == PGRES_TUPLES_OK or st == PGRES_SINGLE_TUPLE:
+              let tuples = PQntuples(res)
+              let fields = PQnfields(res)
+              if tuples > 0 and fields > 0:
+                for r in 0..<tuples:
+                  var tupl = initSequence(fields)
+                  for f in 0..<fields:
+                    tupl[f] = toPreserves($PQgetvalue(res, r, f))
+                  discard publish(turn, target, tupl)
+            else:
+              discard publish(turn, ds, SqlError(
+                  msg: $PQresStatus(st),
+                  context: $PQresultErrorMessage(res),
+                ))
+            PQclear(res)
      else:
        stderr.writeLine "refusing to do anything when status is ", status
    do:
@ -127,6 +153,6 @@ proc spawnPostgreActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
 when isMainModule:
  import syndicate/relays

-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnPostgreActor(turn, ds)
--- a/src/rofi_script_actor.nim
+++ b/src/rofi_script_actor.nim
@ -10,8 +10,8 @@ import ./schema/rofi
 if getEnv("ROFI_OUTSIDE") == "":
  quit("run this program in rofi")

-runActor("rofi_script_actor") do (turn: var Turn):
-  resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+runActor("rofi_script_actor") do (turn: Turn):
+  resolveEnvironment(turn) do (turn: Turn; ds: Cap):
    case paramCount()
    of 0:
      let pat = ?:Options
--- a/src/schema/config.nim
+++ b/src/schema/config.nim
@ -10,6 +10,12 @@ type
  WebsocketArguments* {.preservesRecord: "websocket".} = object
    `field0`*: WebsocketArgumentsField0

+  HttpClientArgumentsField0* {.preservesDictionary.} = object
+    `dataspace`* {.preservesEmbedded.}: EmbeddedRef
+
+  HttpClientArguments* {.preservesRecord: "http-client".} = object
+    `field0`*: HttpClientArgumentsField0
+
  JsonTranslatorArgumentsField0* {.preservesDictionary.} = object
    `argv`*: seq[string]
    `dataspace`* {.preservesEmbedded.}: EmbeddedRef
@ -117,7 +123,8 @@ type
    `host`*: string
    `port`*: BiggestInt

-proc `$`*(x: WebsocketArguments | JsonTranslatorArguments | SocketAddress |
+proc `$`*(x: WebsocketArguments | HttpClientArguments | JsonTranslatorArguments |
+    SocketAddress |
    Base64DecoderArguments |
    JsonTranslatorConnected |
    JsonSocketTranslatorArguments |
@ -136,7 +143,9 @@ proc `$`*(x: WebsocketArguments | JsonTranslatorArguments | SocketAddress |
    Tcp): string =
  `$`(toPreserves(x))

-proc encode*(x: WebsocketArguments | JsonTranslatorArguments | SocketAddress |
+proc encode*(x: WebsocketArguments | HttpClientArguments |
+    JsonTranslatorArguments |
+    SocketAddress |
    Base64DecoderArguments |
    JsonTranslatorConnected |
    JsonSocketTranslatorArguments |
--- a/src/schema/sql.nim
+++ b/src/schema/sql.nim
@ -4,11 +4,15 @@ import

 type
  Query* {.preservesRecord: "query".} = object
-    `statement`*: string
+    `statement`*: seq[Value]
    `target`* {.preservesEmbedded.}: Value

-proc `$`*(x: Query): string =
+  SqlError* {.preservesRecord: "sql-error".} = object
+    `msg`*: string
+    `context`*: string
+
+proc `$`*(x: Query | SqlError): string =
  `$`(toPreserves(x))

-proc encode*(x: Query): seq[byte] =
+proc encode*(x: Query | SqlError): seq[byte] =
  encode(toPreserves(x))
--- a/src/sqlite_actor.nim
+++ b/src/sqlite_actor.nim
@ -54,8 +54,19 @@ proc finalize(stmt: Stmt): cint {.importSqlite3.}

 doAssert libversion_number() == SQLITE_VERSION_NUMBER

-proc logError(db: Sqlite3; context: string) =
-  writeLine(stderr, errmsg(db), ": ", context)
+proc assertError(facet: Facet; cap: Cap; db: Sqlite3; context: string) =
+  run(facet) do (turn: Turn):
+    publish(turn, cap, SqlError(
+      msg: $errmsg(db),
+      context: context,
+    ))
+
+proc assertError(facet: Facet; cap: Cap; msg, context: string) =
+  run(facet) do (turn: Turn):
+    publish(turn, cap, SqlError(
+      msg: msg,
+      context: context,
+    ))

 proc extractValue(stmt: Stmt; col: cint): Value =
  case column_type(stmt, col)
@ -78,37 +89,61 @@ proc extractTuple(stmt: Stmt; arity: cint): Value =
  result = initSequence(arity)
  for col in 0..<arity: result[col] = extractValue(stmt, col)

-proc spawnSqliteActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawn("sqlite-actor", turn) do (turn: var Turn):
+proc renderSql(tokens: openarray[Value]): string =
+  for token in tokens:
+    if result.len > 0: result.add ' '
+    case token.kind
+    of pkSymbol:
+      result.add token.symbol.string
+    of pkString:
+      result.add '\''
+      result.add token.string
+      result.add '\''
+    of pkFloat, pkRegister, pkBigInt:
+      result.add $token
+    of pkBoolean:
+      if token.bool: result.add '1'
+      else: result.add '0'
+    else:
+      return ""
+
+proc spawnSqliteActor*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawn("sqlite-actor", turn) do (turn: Turn):
    during(turn, root, ?:SqliteArguments) do (path: string, ds: Cap):
-      stderr.writeLine("opening SQLite database ", path)
-      var db: Sqlite3
-      if open_v2(path, addr db, SQLITE_OPEN_READONLY, nil) != SQLITE_OK:
-        logError(db, path)
-      else:
-        during(turn, ds, ?:Query) do (statement: string, target: Cap):
-          var stmt: Stmt
-          if prepare_v2(db, statement, statement.len.cint, addr stmt, nil) != SQLITE_OK:
-            logError(db, statement)
-          else:
-            try:
-              let arity = column_count(stmt)
-              var res = step(stmt)
-              while res == SQLITE_ROW:
-                var rec = extractTuple(stmt, arity)
-                discard publish(turn, target, rec)
-                res = step(stmt)
-              assert res != 100
-              if res != SQLITE_DONE:
-                logError(db, statement)
-            finally:
-              if finalize(stmt) != SQLITE_OK: logError(db, statement)
-    do:
-      close(db)
-      stderr.writeLine("closed SQLite database ", path)
+      linkActor(turn, path) do (turn: Turn):
+        let facet = turn.facet
+        stderr.writeLine("opening SQLite database ", path)
+        var db: Sqlite3
+        if open_v2(path, addr db, SQLITE_OPEN_READONLY, nil) != SQLITE_OK:
+          assertError(facet, ds, db, path)
+        else:
+          turn.onStop do (turn: Turn):
+            close(db)
+            stderr.writeLine("closed SQLite database ", path)
+          during(turn, ds, ?:Query) do (statement: seq[Value], target: Cap):
+            var
+              stmt: Stmt
+              text = renderSql statement
+            if text == "":
+              assertError(facet, target, "invalid statement", $statement)
+            elif prepare_v2(db, text, text.len.cint, addr stmt, nil) != SQLITE_OK:
+              assertError(facet, target, db, text)
+            else:
+              try:
+                let arity = column_count(stmt)
+                var res = step(stmt)
+                while res == SQLITE_ROW:
+                  var rec = extractTuple(stmt, arity)
+                  discard publish(turn, target, rec)
+                  res = step(stmt)
+                assert res != 100
+                if res != SQLITE_DONE:
+                  assertError(facet, target, db, text)
+              finally:
+                if finalize(stmt) != SQLITE_OK: assertError(facet, target, db, text)

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnSqliteActor(turn, ds)
--- a/src/syndesizer.nim
+++ b/src/syndesizer.nim
@ -15,8 +15,8 @@ import ./syndesizer/[
  pulses,
  xml_translator]

-runActor("syndesizer") do (turn: var Turn):
-  resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+runActor("syndesizer") do (turn: Turn):
+  resolveEnvironment(turn) do (turn: Turn; ds: Cap):
    discard spawnTimerDriver(turn, ds)
    discard spawnBase64Decoder(turn, ds)
    discard spawnCacheActor(turn, ds)
--- a/src/syndesizer/base64_decoder.nim
+++ b/src/syndesizer/base64_decoder.nim
@ -3,33 +3,33 @@

 import std/[base64, os]
 import pkg/hashlib/misc/blake2
-import preserves, syndicate
+import preserves, preserves/sugar, syndicate
 import ../schema/config
 import ../schema/base64 as schema

 export Base64DecoderArguments
 export schema

-proc spawnBase64Decoder*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawnActor(turn, "base64-decoder") do (turn: var Turn):
+proc spawnBase64Decoder*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawnActor(turn, "base64-decoder") do (turn: Turn):
    let tmpDir = getTempDir()
    during(turn, root, ?:Base64DecoderArguments) do (ds: Cap):

-      let decTextPat = ?Observe(pattern: !Base64Text) ?? { 0: grabLit() }
+      let decTextPat = observePattern(!Base64Text, { @[%0]: grabLit() })
      during(turn, ds, decTextPat) do (txt: string):
        discard publish(turn, ds, Base64Text(
            txt: txt,
            bin: cast[seq[byte]](decode(txt)),
          ))

-      let encTextPat = ?Observe(pattern: !Base64Text) ?? { 1: grabLit() }
+      let encTextPat = observePattern(!Base64Text, { @[%1]: grabLit() })
      during(turn, ds, encTextPat) do (bin: seq[byte]):
        discard publish(turn, ds, Base64Text(
            txt: encode(bin),
            bin: bin,
          ))

-      let decFilePat = ?Observe(pattern: !Base64File) ?? { 0: grabLit() }
+      let decFilePat = observePattern( !Base64File, { @[%0]: grabLit() })
      during(turn, ds, decFilePat) do (txt: string):
        var bin = decode(txt)
        var ctx = init[BLAKE2B_512]()
@ -46,6 +46,6 @@ proc spawnBase64Decoder*(turn: var Turn; root: Cap): Actor {.discardable.} =

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnBase64Decoder(turn, ds)
--- a/src/syndesizer/cache_actor.nim
+++ b/src/syndesizer/cache_actor.nim
@ -18,9 +18,9 @@ type CacheEntity {.final.} = ref object of Entity
  pattern: Pattern
  lifetime: float64

-method publish(cache: CacheEntity; turn: var Turn; ass: AssertionRef; h: Handle) =
+method publish(cache: CacheEntity; turn: Turn; ass: AssertionRef; h: Handle) =
  ## Re-assert pattern captures in a sub-facet.
-  discard inFacet(turn) do (turn: var Turn):
+  discard inFacet(turn) do (turn: Turn):
    # TODO: a seperate facet for every assertion, too much?
    var ass = depattern(cache.pattern, ass.value.sequence)
      # Build an assertion with what he have of the pattern and capture.
@ -30,12 +30,12 @@ method publish(cache: CacheEntity; turn: var Turn; ass: AssertionRef; h: Handle)
      stop(turn) # end this facet

 proc isObserve(pat: Pattern): bool =
-  pat.orKind == PatternKind.DCompound and
-    pat.dcompound.orKind == DCompoundKind.rec and
-      pat.dcompound.rec.label.isSymbol"Observe"
+  pat.orKind == PatternKind.group and
+    pat.group.type.orKind == GroupTypeKind.rec and
+      pat.group.type.rec.label.isSymbol"Observe"

-proc spawnCacheActor*(turn: var Turn; root: Cap): Actor =
-  spawnActor(turn, "cache_actor") do (turn: var Turn):
+proc spawnCacheActor*(turn: Turn; root: Cap): Actor =
+  spawnActor(turn, "cache_actor") do (turn: Turn):
    during(turn, root, ?:CacheArguments) do (ds: Cap, lifetime: float64):
      onPublish(turn, ds, ?:Observe) do (pat: Pattern, obs: Cap):
        var cache: CacheEntity
@ -52,7 +52,7 @@ proc spawnCacheActor*(turn: var Turn; root: Cap): Actor =

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      discard spawnTimerDriver(turn, ds)
      discard spawnCacheActor(turn, ds)
--- a/src/syndesizer/file_system_usage.nim
+++ b/src/syndesizer/file_system_usage.nim
@ -2,15 +2,15 @@
 # SPDX-License-Identifier: Unlicense

 import std/[dirs, os, paths]
-import preserves
+import preserves, preserves/sugar
 import syndicate

 import ../schema/[assertions, config]

-proc spawnFileSystemUsageActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawn("file-system-usage", turn) do (turn: var Turn):
+proc spawnFileSystemUsageActor*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawn("file-system-usage", turn) do (turn: Turn):
    during(turn, root, ?:FileSystemUsageArguments) do (ds: Cap):
-      var pat = ?Observe(pattern: !FileSystemUsage) ?? { 0: grab() }
+      let pat = observePattern(!FileSystemUsage, { @[%0]: grab() })
      during(turn, ds, pat) do (lit: Literal[string]):
        var ass = FileSystemUsage(path: lit.value)
        if fileExists(ass.path): ass.size = getFileSize(ass.path)
@ -23,6 +23,6 @@ proc spawnFileSystemUsageActor*(turn: var Turn; root: Cap): Actor {.discardable.

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      discard spawnFileSystemUsageActor(turn, ds)
--- a/src/syndesizer/http_driver.nim
+++ b/src/syndesizer/http_driver.nim
@ -8,7 +8,7 @@ import pkg/syndicate/drivers/http_driver
 import pkg/taps
 import ../schema/config

-proc spawnHttpDriver*(turn: var Turn; ds: Cap): Actor {.discardable.}=
+proc spawnHttpDriver*(turn: Turn; ds: Cap): Actor {.discardable.}=
  http_driver.spawnHttpDriver(turn, ds)
  during(turn, ds, ?:HttpDriverArguments) do (ds: Cap):
    http_driver.spawnHttpDriver(turn, ds)
@ -30,13 +30,13 @@ when isMainModule:
            return
      quit("failed to parse command line for route to Syndicate gatekeeper")

-    runActor("main") do (turn: var Turn):
+    runActor("main") do (turn: Turn):
      let ds = newDataspace(turn)
      spawnRelays(turn, ds)
      resolve(turn, ds, envRoute(), spawnHttpDriver)

  else:

-    runActor("main") do (turn: var Turn):
-      resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+    runActor("main") do (turn: Turn):
+      resolveEnvironment(turn) do (turn: Turn; ds: Cap):
        spawnHttpDriver(turn, ds)
--- a/src/syndesizer/json_socket_translator.nim
+++ b/src/syndesizer/json_socket_translator.nim
@ -14,9 +14,9 @@ template translateSocketBody {.dirty.} =
    dec = newBufferedDecoder(0)
    buf = new string #TODO: get a pointer into the decoder
    alive = true
-  proc kill(turn: var Turn) =
+  proc kill(turn: Turn) =
    alive = false
-  proc setup(turn: var Turn) =
+  proc setup(turn: Turn) =
    # Closure, not CPS.
    onMessage(turn, ds, ?:SendJson) do (data: JsonNode):
      if alive:
@ -38,7 +38,7 @@ template translateSocketBody {.dirty.} =
      dec.feed(buf[])
      var data = dec.parse()
      if data.isSome:
-        proc send(turn: var Turn) =
+        proc send(turn: Turn) =
          # Closure, not CPS.
          message(turn, ds, initRecord("recv", data.get))
        run(facet, send)
@ -59,19 +59,19 @@ proc translateSocket(facet: Facet; ds: Cap; sa: UnixAddress) {.asyncio.} =
  socket[] = conn
  translateSocketBody()

-proc spawnJsonSocketTranslator*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawnActor(turn, "json-socket-translator") do (turn: var Turn):
+proc spawnJsonSocketTranslator*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawnActor(turn, "json-socket-translator") do (turn: Turn):
    during(turn, root, ?:JsonSocketTranslatorArguments) do (ds: Cap, sa: TcpAddress):
-      linkActor(turn, "json-socket-translator") do (turn: var Turn):
+      linkActor(turn, "json-socket-translator") do (turn: Turn):
        discard trampoline:
          whelp translateSocket(turn.facet, ds, sa)
    during(turn, root, ?:JsonSocketTranslatorArguments) do (ds: Cap, sa: UnixAddress):
-      linkActor(turn, "json-socket-translator") do (turn: var Turn):
+      linkActor(turn, "json-socket-translator") do (turn: Turn):
        discard trampoline:
          whelp translateSocket(turn.facet, ds, sa)

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnJsonSocketTranslator(turn, ds)
--- a/src/syndesizer/json_translator.nim
+++ b/src/syndesizer/json_translator.nim
@ -19,8 +19,8 @@ proc runChild(params: seq[string]): string =
  if result == "":
    stderr.writeLine "no ouput"

-proc spawnJsonStdioTranslator*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawnActor(turn, "json-stdio-translator") do (turn: var Turn):
+proc spawnJsonStdioTranslator*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawnActor(turn, "json-stdio-translator") do (turn: Turn):
    during(turn, root, ?:JsonTranslatorArguments) do (argv: seq[string], ds: Cap):
      var js = parseJson(runChild(argv))
      message(turn, ds,  RecvJson(data: js))
@ -28,6 +28,6 @@ proc spawnJsonStdioTranslator*(turn: var Turn; root: Cap): Actor {.discardable.}

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnJsonStdioTranslator(turn, ds)
--- a/src/syndesizer/pulses.nim
+++ b/src/syndesizer/pulses.nim
@ -2,7 +2,8 @@
 # SPDX-License-Identifier: Unlicense

 import std/[options, tables, times]
-import preserves, syndicate, syndicate/drivers/timers
+import preserves, preserves/sugar
+import syndicate, syndicate/drivers/timers

 import ../schema/[assertions, config]

@ -16,7 +17,7 @@ type PulseEntity {.final.} = ref object of Entity
  observePattern: Pattern
  observing: bool

-proc schedule(turn: var Turn; pulse: PulseEntity) =
+proc schedule(turn: Turn; pulse: PulseEntity) =
  ## Schedule the next pulse.
  ## The next pulse will be schedule using the current time as
  ## reference point and not the moment of the previous pulse.
@ -26,7 +27,7 @@ proc schedule(turn: var Turn; pulse: PulseEntity) =
      observer: pulse.self,
    ))

-method publish(pulse: PulseEntity; turn: var Turn; ass: AssertionRef; h: Handle) =
+method publish(pulse: PulseEntity; turn: Turn; ass: AssertionRef; h: Handle) =
  ## Publish observers in reponse to <later-than …> assertions.
  pulse.timers.target.retract(turn, pulse.timerHandle)
  schedule(turn, pulse)
@ -35,7 +36,7 @@ method publish(pulse: PulseEntity; turn: var Turn; ass: AssertionRef; h: Handle)
    pulse.target.publish(turn, a, h)
  pulse.target.sync(turn, pulse.self)

-method message(pulse: PulseEntity; turn: var Turn; v: AssertionRef) =
+method message(pulse: PulseEntity; turn: Turn; v: AssertionRef) =
  ## Retract observers in response to a sync message.
  pulse.observing = false
  for h in pulse.observers.keys:
@ -45,7 +46,7 @@ type ProxyEntity {.final.} = ref object of Entity
  ## A proxy `Entity` that diverts observers to a `PulseEntity`.
  pulse: PulseEntity

-method publish(proxy: ProxyEntity; turn: var Turn; ass: AssertionRef; h: Handle) =
+method publish(proxy: ProxyEntity; turn: Turn; ass: AssertionRef; h: Handle) =
  ## Proxy assertions that are not observations.
  if proxy.pulse.observePattern.matches ass.value:
    if proxy.pulse.observers.len == 0:
@ -54,7 +55,7 @@ method publish(proxy: ProxyEntity; turn: var Turn; ass: AssertionRef; h: Handle)
  else:
    proxy.pulse.target.publish(turn, ass, h)

-method retract(proxy: ProxyEntity; turn: var Turn; h: Handle) =
+method retract(proxy: ProxyEntity; turn: Turn; h: Handle) =
  ## Retract proxied assertions.
  var obs: AssertionRef
  if proxy.pulse.observers.pop(h, obs):
@ -65,15 +66,15 @@ method retract(proxy: ProxyEntity; turn: var Turn; h: Handle) =
  else:
    proxy.pulse.target.retract(turn, h)

-method message(proxy: ProxyEntity; turn: var Turn; v: AssertionRef) =
+method message(proxy: ProxyEntity; turn: Turn; v: AssertionRef) =
  ## Proxy mesages.
  proxy.pulse.target.message(turn, v)

-method sync(proxy: ProxyEntity; turn: var Turn; peer: Cap) =
+method sync(proxy: ProxyEntity; turn: Turn; peer: Cap) =
  ## Proxy sync.
  proxy.pulse.target.sync(turn, peer)

-proc newProxyEntity(turn: var Turn; timers, ds: Cap; period: float): ProxyEntity =
+proc newProxyEntity(turn: Turn; timers, ds: Cap; period: float): ProxyEntity =
  new result
  result.pulse = PulseEntity(
      target: ds.target,
@ -83,11 +84,11 @@ proc newProxyEntity(turn: var Turn; timers, ds: Cap; period: float): ProxyEntity
    )
  result.pulse.self = newCap(turn, result.pulse)

-proc spawnPulseActor*(turn: var Turn; root: Cap): Actor =
+proc spawnPulseActor*(turn: Turn; root: Cap): Actor =
  ## Spawn an actor that retracts and re-asserts observers on
  ## a timed pulse. Requires a timer service on the `root` capability.
-  spawnActor(turn, "pulse") do (turn: var Turn):
-    let grabPeriod = ?Observe(pattern: !Pulse) ?? { 0: grab() }
+  spawnActor(turn, "pulse") do (turn: Turn):
+    let grabPeriod = observePattern(!Pulse, { @[%0]: grab() })
    during(turn, root, ?:PulseArguments) do (ds: Cap):
      during(turn, ds, grabPeriod) do (lit: Literal[float]):
        if lit.value < 0.000_1:
@ -99,6 +100,6 @@ proc spawnPulseActor*(turn: var Turn; root: Cap): Actor =

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      discard spawnPulseActor(turn, ds)
--- a/src/syndesizer/xml_translator.nim
+++ b/src/syndesizer/xml_translator.nim
@ -2,7 +2,7 @@
 # SPDX-License-Identifier: Unlicense

 import std/[options, parsexml, xmlparser, xmltree]
-import preserves, preserves/xmlhooks
+import preserves, preserves/sugar, preserves/xmlhooks
 import syndicate

 import ../schema/[assertions, config]
@ -17,17 +17,18 @@ proc translatePreserves(pr: Value): XmlTranslation {.gcsafe.} =
  var xn = result.pr.preservesTo(XmlNode)
  if xn.isSome: result.xml = $get(xn)

-proc spawnXmlTranslator*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawnActor(turn, "xml-translator") do (turn: var Turn):
+proc spawnXmlTranslator*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawnActor(turn, "xml-translator") do (turn: Turn):
    during(turn, root, ?:XmlTranslatorArguments) do (ds: Cap):
-      let obsPat = ?Observe(pattern: !XmlTranslation)
-      during(turn, ds, obsPat ?? {0: grab()}) do (xs: Literal[string]):
+      let xmlPat = observePattern(!XmlTranslation, {@[%0]:grab()})
+      during(turn, ds, xmlPat) do (xs: Literal[string]):
        publish(turn, ds, translateXml(xs.value))
-      during(turn, ds, obsPat ?? {1: grab()}) do (pr: Literal[Value]):
+      let prPat = observePattern(!XmlTranslation, {@[%1]:grab()})
+      during(turn, ds, prPat) do (pr: Literal[Value]):
        publish(turn, ds, translatePreserves(pr.value))

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnXmlTranslator(turn, ds)
--- a/src/syndump.nim
+++ b/src/syndump.nim
@ -36,19 +36,19 @@ proc toLine(values: seq[Value]; prefix: char): string =
    add(result, $v)
  add(result, '\n')

-method publish(dump: DumpEntity; turn: var Turn; ass: AssertionRef; h: Handle) =
+method publish(dump: DumpEntity; turn: Turn; ass: AssertionRef; h: Handle) =
  var values = ass.value.sequence
  stdout.write(values.toLine('+'))
  stdout.flushFile()
  dump.assertions[h] = values

-method retract(dump: DumpEntity; turn: var Turn; h: Handle) =
+method retract(dump: DumpEntity; turn: Turn; h: Handle) =
  var values: seq[Value]
  if dump.assertions.pop(h, values):
    stdout.write(values.toLine('-'))
    stdout.flushFile()

-method message*(dump: DumpEntity; turn: var Turn; ass: AssertionRef) =
+method message*(dump: DumpEntity; turn: Turn; ass: AssertionRef) =
  stdout.write(ass.value.sequence.toLine('!'))
  stdout.flushFile()

@ -60,8 +60,8 @@ proc main =
  let
    patterns = inputPatterns()
    entity = DumpEntity()
-  runActor("syndex_card") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("syndex_card") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      for pat in patterns:
        discard observe(turn, ds, pat, entity)

--- a/src/xslt_actor.nim
+++ b/src/xslt_actor.nim
@ -2,7 +2,7 @@
 # SPDX-License-Identifier: Unlicense

 import std/[os, strutils]
-import preserves, syndicate
+import preserves, preserves/sugar, syndicate
 import ./schema/[assertions, config]

 {.passC: staticExec("pkg-config --cflags libxslt").}
@ -173,11 +173,11 @@ proc toPreservesHook*(xn: xmlNodePtr): Value =
  preserveSiblings(items, xn)
  items[0]

-proc spawnXsltActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
-  spawnActor(turn, "xslt") do (turn: var Turn):
+proc spawnXsltActor*(turn: Turn; root: Cap): Actor {.discardable.} =
+  spawnActor(turn, "xslt") do (turn: Turn):
    initLibXml()
    during(turn, root, ?:XsltArguments) do (ds: Cap):
-      let sheetsPat = ?Observe(pattern: !XsltTransform) ?? {0: grab(), 1: grab()}
+      let sheetsPat = observePattern(!XsltTransform, {@[%0]: grab(), @[%1]: grab()})
      during(turn, ds, sheetsPat) do (stylesheet: Literal[string], input: Literal[string]):
        let cur = loadStylesheet(stylesheet.value)
        if cur.isNil:
@ -206,6 +206,6 @@ proc spawnXsltActor*(turn: var Turn; root: Cap): Actor {.discardable.} =

 when isMainModule:
  import syndicate/relays
-  runActor("main") do (turn: var Turn):
-    resolveEnvironment(turn) do (turn: var Turn; ds: Cap):
+  runActor("main") do (turn: Turn):
+    resolveEnvironment(turn) do (turn: Turn; ds: Cap):
      spawnXsltActor(turn, ds)
--- a/syndicate_utils.nimble
+++ b/syndicate_utils.nimble
@ -1,13 +1,13 @@
 # Package

-version = "20240407"
+version = "20240509"
 author        = "Emery Hemingway"
 description   = "Utilites for Syndicated Actors and Synit"
 license       = "unlicense"
 srcDir        = "src"
-bin           = @["mintsturdyref", "mount_actor", "msg", "postgre_actor", "preserve_process_environment", "rofi_script_actor", "sqlite_actor", "syndesizer", "syndump", "xslt_actor"]
+bin           = @["http_client", "mintsturdyref", "mount_actor", "msg", "postgre_actor", "preserve_process_environment", "rofi_script_actor", "sqlite_actor", "syndesizer", "syndump", "xslt_actor"]


 # Dependencies

-requires "http://git.syndicate-lang.org/ehmry/syndicate-nim.git >= 20240405", "https://github.com/ehmry/nim-sys.git#4ef3b624db86e331ba334e705c1aa235d55b05e1", "https://git.sr.ht/~ehmry/nim_taps >= 20240405"
+requires "https://git.syndicate-lang.org/ehmry/syndicate-nim.git >= 20240507", "https://github.com/ehmry/nim-sys.git#4ef3b624db86e331ba334e705c1aa235d55b05e1", "https://git.sr.ht/~ehmry/nim_taps >= 20240405"
Author	SHA1	Message	Date
Emery Hemingway	3a0bd1cd02	Make a proper default.nix, cleanup lockfile	2024-05-10 12:08:51 +02:00
Emery Hemingway	cda940cf75	Update syndicate dependency	2024-05-09 18:31:20 +02:00
Emery Hemingway	bf0b5d6b86	Add http_client	2024-05-09 18:31:20 +02:00
Emery Hemingway	b3a417a072	Replace "var Turn" with "Turn"	2024-04-30 13:56:48 +02:00
Emery Hemingway	48408d2763	Use new dataspace patterns	2024-04-23 10:25:03 +02:00
Emery Hemingway	494418540a	Update syndicate library	2024-04-09 10:14:58 +01:00
Emery Hemingway	e954fdefec	SQL: decompose SQL statements and assert errors	2024-04-09 10:14:38 +01:00
Emery Hemingway	de7683b467	Add http driver to README	2024-04-08 14:10:34 +01:00