dashboard: write growing list into page when serving

2 files changed, 12 insertions, 7 deletions

diff --git a/src/api/dashboard/dashboard.html b/src/api/dashboard/dashboard.html
index 091d7ee..dd764b6 100644
--- a/src/api/dashboard/dashboard.html
+++ b/src/api/dashboard/dashboard.html
@@ -162,9 +162,9 @@ const PAGE_VERSION = "__PAGE_VERSION__";
 let state = null;
 let stateAt = 0;
 
-// Fields that grow by themselves (`GROWING` and `is_age` in the node's dashboard).
-const GROWING = new Set(["uptimeSecs", "dormantForSecs", "divergedForSecs", "observedSecs",
-  "lastFromNeighbourSecs", "oldestQuarantineSecs"]);
+// Fields that grow by themselves: the node's list (`GROWING` and `is_age` in its
+// dashboard), filled in when it serves the page.
+const GROWING = new Set(__GROWING__);
 const isAge = key => key === "secsAgo" || key.endsWith("SecsAgo") || GROWING.has(key);
 const elapsed = () => Math.floor((Date.now() - stateAt) / 1000);
 const aged = (key, value) =>
diff --git a/src/api/dashboard/mod.rs b/src/api/dashboard/mod.rs
index 0a15570..87f5aeb 100644
--- a/src/api/dashboard/mod.rs
+++ b/src/api/dashboard/mod.rs
@@ -321,8 +321,8 @@ fn links_json(links: &[Link]) -> JsonValue {
         .collect()
 }
 
-/// Fields that grow by themselves besides those named `…SecsAgo` (the page knows
-/// them too).
+/// Fields that grow by themselves besides those named `…SecsAgo`; the page gets the
+/// list when served (`GROWING_MARK`).
 const GROWING: &[&str] = &[
     "uptimeSecs",
     "dormantForSecs",
@@ -399,6 +399,8 @@ pub(crate) fn router(state: AppState) -> Router<AppState> {
 const PAGE: &str = include_str!("dashboard.html");
 /// Where the page says which version of it it is.
 const PAGE_VERSION_MARK: &str = "__PAGE_VERSION__";
+/// Where the page gets the age fields (`GROWING`), so the list is kept once.
+const GROWING_MARK: &str = "__GROWING__";
 
 /// The page's version (a hash of it), and the page saying so: a page whose version
 /// differs from the snapshot's `page` was served by another build, and reloads.
@@ -406,12 +408,15 @@ fn page() -> &'static (String, String) {
     static PAGE_SERVED: OnceLock<(String, String)> = OnceLock::new();
     PAGE_SERVED.get_or_init(|| {
         use sha2::{Digest, Sha256};
-        let version: String = Sha256::digest(PAGE.as_bytes())
+        let growing = serde_json::to_string(GROWING).unwrap_or_else(|_| "[]".to_owned());
+        let page = PAGE.replace(GROWING_MARK, &growing);
+        // Of the page with its list: a new list is a new version too.
+        let version: String = Sha256::digest(page.as_bytes())
             .iter()
             .take(8)
             .map(|byte| format!("{byte:02x}"))
             .collect();
-        let served = PAGE.replace(PAGE_VERSION_MARK, &version);
+        let served = page.replace(PAGE_VERSION_MARK, &version);
         (version, served)
     })
 }