dashboard: remake switch delay

3 files changed, 18 insertions, 5 deletions

diff --git a/docs/dashboard.md b/docs/dashboard.md
index 398a65b..091e9f7 100644
--- a/docs/dashboard.md
+++ b/docs/dashboard.md
@@ -280,7 +280,10 @@ this node coordinating it: `compact` (the same content, without its history),
 look at first) or `import` (an Automerge document, a backup, uploaded as it is); for the
 last two, rules for the writes made meanwhile (a path prefix moved to another, or
 dropped; what no rule covers is quarantined on the node that made it), and for any, how
-long votes are collected. The answer shows below: the remake's ID, or why it was refused
+long votes are collected and how long nodes wait after a successful vote before
+switching (the switch delay, `switchDelay`; below a keepalive interval only with "even
+below a keepalive interval" ticked, the API's `?force=switchDelay`: slow nodes may then
+miss the commit before the others switch, and rejoin). The answer shows below: the remake's ID, or why it was refused
 (and the API's override, if any). The map shows the votes as they come.
 
 ## Console
diff --git a/src/api/dashboard/dashboard.html b/src/api/dashboard/dashboard.html
index 9a395bb..771b49b 100644
--- a/src/api/dashboard/dashboard.html
+++ b/src/api/dashboard/dashboard.html
@@ -366,6 +366,10 @@
       </div>
       <label>settle <input id="remake-settle" size="6" placeholder="default"
         title="How long votes are collected: seconds, or e.g. 500ms, 8m; empty: twice the dormancy threshold"></label>
+      <label>switch delay <input id="remake-switch-delay" size="6" placeholder="default"
+        title="How long nodes wait after the vote succeeded before switching, so the commit reaches every node first: seconds, or e.g. 500ms, 1m; empty: one keepalive interval"></label>
+      <label title="Accept a switch delay below a keepalive interval (?force=switchDelay): slow nodes may miss the commit before the others switch, and have to rejoin"><input
+        type="checkbox" id="remake-force-switch-delay"> even below a keepalive interval</label>
       <p class="note">Writes made meanwhile that no rule covers are quarantined on the node
         that made them.</p>
       <div class="actions"><button type="submit" class="toggle">propose</button>
@@ -2947,13 +2951,17 @@ remakeForm.addEventListener("submit", event => {
   event.preventDefault();
   const kind = document.getElementById("remake-kind").value;
   const settle = document.getElementById("remake-settle").value.trim();
+  const switchDelay = document.getElementById("remake-switch-delay").value.trim();
+  const force = document.getElementById("remake-force-switch-delay").checked
+    ? "force=switchDelay" : "";
   let request;
   if (kind === "import") {
     // The document as it is (octet-stream): its options in the query.
     const file = document.getElementById("remake-import-file").files[0];
     if (!file) { remakeResult("Choose the Automerge document to import.", true); return; }
-    const options = new URLSearchParams();
+    const options = new URLSearchParams(force);
     if (settle) options.set("settle", settle);
+    if (switchDelay) options.set("switchDelay", switchDelay);
     const rules = remakeRules();
     if (rules.length) options.set("rules", JSON.stringify(rules));
     const query = options.size ? "?" + options : "";
@@ -2962,6 +2970,7 @@ remakeForm.addEventListener("submit", event => {
   } else {
     const body = { kind };
     if (settle) body.settle = settle;
+    if (switchDelay) body.switchDelay = switchDelay;
     if (kind === "replace") {
       let parsed;
       try {
@@ -2974,7 +2983,7 @@ remakeForm.addEventListener("submit", event => {
       const rules = remakeRules();
       if (rules.length) body.spec.rules = rules;
     }
-    request = fetch("remakes", { method: "POST", body: JSON.stringify(body),
+    request = fetch("remakes" + (force ? "?" + force : ""), { method: "POST", body: JSON.stringify(body),
       headers: { "Content-Type": "application/json" } });
   }
   remakeResult("Proposing…", false);
@@ -2986,7 +2995,8 @@ remakeForm.addEventListener("submit", event => {
           ". The map shows the votes as they come.", false);
       } else {
         remakeResult(response.status + ": " + (report.error || response.statusText) +
-          (report.force ? " (the API takes ?force=" + report.force + ")" : ""), true);
+          (report.force === "switchDelay" ? " (tick \u201ceven below a keepalive interval\u201d)"
+            : report.force ? " (the API takes ?force=" + report.force + ")" : ""), true);
       }
     })
     .catch(error => remakeResult("Proposing failed: " + error, true));
diff --git a/src/remake/api.rs b/src/remake/api.rs
index 8fd0c5b..7888c37 100644
--- a/src/remake/api.rs
+++ b/src/remake/api.rs
@@ -425,7 +425,7 @@ async fn start_kind<H: Host>(
                     "switchDelay must be at least {} (one keepalive interval), so the commit reaches every node before they switch; add ?force=switchDelay to override",
                     crate::units::format_duration(keepalive)
                 ),
-                None,
+                Some(json!({ "force": "switchDelay" })),
             );
         }
         _ => {}