From 3b0e4e2fe2a7e640bc12a3dc13ca573a2ac2eb21 Mon Sep 17 00:00:00 2001
From: Pete Vilter <pete.vilter@gmail.com>
Date: Sun, 9 Jun 2024 03:59:55 -0400
Subject: [PATCH] disallow versions with same txn id (#479)

* disallow versions with same txn id

* logging tweak
---
 apps/actors/systems/kvSync/client.ts          |  4 +-
 apps/actors/systems/kvSync/examples/chat.tsx  |  5 ++-
 .../kvSync/examples/common/kvInspector.tsx    | 43 +++++++++----------
 apps/actors/systems/kvSync/mutations/run.ts   | 17 +++++++-
 4 files changed, 42 insertions(+), 27 deletions(-)

diff --git a/apps/actors/systems/kvSync/client.ts b/apps/actors/systems/kvSync/client.ts
index 518d58ea..cfa450fd 100644
--- a/apps/actors/systems/kvSync/client.ts
+++ b/apps/actors/systems/kvSync/client.ts
@@ -18,7 +18,7 @@ import {
 } from "./types";
 import * as effects from "../../effects";
 import { mapObj, randStep } from "../../../../util/util";
-import { runMutation } from "./mutations/run";
+import { addNewVersion, runMutation } from "./mutations/run";
 import { InterpreterState } from "./mutations/builtins";
 
 export type QueryStatus = "Loading" | "Online";
@@ -123,7 +123,7 @@ function processLiveQueryUpdate(
     const key = update.key;
     switch (update.type) {
       case "Updated":
-        newData[key] = [...(newData[key] || []), update.value];
+        newData[key] = addNewVersion(newData, key, update.value);
         break;
       case "Deleted":
         delete newData[key]; // TODO: tombstone?
diff --git a/apps/actors/systems/kvSync/examples/chat.tsx b/apps/actors/systems/kvSync/examples/chat.tsx
index a4dfdc35..0bf1e568 100644
--- a/apps/actors/systems/kvSync/examples/chat.tsx
+++ b/apps/actors/systems/kvSync/examples/chat.tsx
@@ -174,7 +174,10 @@ function SendBox(props: { threadID: string; client: Client }) {
           if (status === "Online") {
             props.client.runMutation("markRead", [props.threadID, latestSeqNo]);
           } else {
-            console.log("not marking read because query status is", status);
+            console.warn(
+              "SendBox: not marking read because query status is",
+              status
+            );
           }
         }}
       />
diff --git a/apps/actors/systems/kvSync/examples/common/kvInspector.tsx b/apps/actors/systems/kvSync/examples/common/kvInspector.tsx
index e412d47f..6fbe764b 100644
--- a/apps/actors/systems/kvSync/examples/common/kvInspector.tsx
+++ b/apps/actors/systems/kvSync/examples/common/kvInspector.tsx
@@ -4,7 +4,7 @@ import { Table } from "./table";
 import { VersionedValue } from "../../types";
 import { getVisibleValue } from "../../mutations/common";
 import { TransactionState, isTxnVisible } from "../../client";
-import { intersperse, reversed } from "../../../../../../util/util";
+import { reversed } from "../../../../../../util/util";
 
 export function KVInspector(props: {
   client: Client;
@@ -34,28 +34,25 @@ export function KVInspector(props: {
         {
           name: "Statuses",
           render: ([key, vvs]) =>
-            intersperse(
-              <></>,
-              reversed(vvs).map((vv) => (
-                // TODO: clicking on this should show the txn trace
-                <span
-                  title={vv.transactionID}
-                  style={{
-                    cursor: "pointer",
-                    textDecoration:
-                      vv.transactionID === props.selectedTxnID
-                        ? "underline"
-                        : "none",
-                  }}
-                  key={vv.transactionID}
-                  onClick={() => props.onSelectTxn(vv.transactionID)}
-                >
-                  {iconForState(
-                    props.client.state.transactions[vv.transactionID].state
-                  )}
-                </span>
-              ))
-            ),
+            reversed(vvs).map((vv) => (
+              // TODO: clicking on this should show the txn trace
+              <span
+                title={vv.transactionID}
+                style={{
+                  cursor: "pointer",
+                  textDecoration:
+                    vv.transactionID === props.selectedTxnID
+                      ? "underline"
+                      : "none",
+                }}
+                key={vv.transactionID}
+                onClick={() => props.onSelectTxn(vv.transactionID)}
+              >
+                {iconForState(
+                  props.client.state.transactions[vv.transactionID].state
+                )}
+              </span>
+            )),
         },
       ]}
     />
diff --git a/apps/actors/systems/kvSync/mutations/run.ts b/apps/actors/systems/kvSync/mutations/run.ts
index da25132f..e4c299b2 100644
--- a/apps/actors/systems/kvSync/mutations/run.ts
+++ b/apps/actors/systems/kvSync/mutations/run.ts
@@ -324,7 +324,7 @@ function doWrite(
   const newVersionedValue: VersionedValue = { transactionID, value };
   const newKVData: KVData = {
     ...kvData,
-    [key]: [...(kvData[key] || []), newVersionedValue],
+    [key]: addNewVersion(kvData, key, newVersionedValue),
   };
   const oldValue = getVisibleValue(isTxnCommitted, kvData, key);
   if (kvData[key]) {
@@ -346,3 +346,18 @@ function doWrite(
     },
   ];
 }
+
+export function addNewVersion(
+  kvData: KVData,
+  key: string,
+  newVersion: VersionedValue
+) {
+  const versions = kvData[key] || [];
+  // Check if the transactionID is already in the list
+  // This can result from overlapping live queries
+  // TODO: this is O(n) and could be O(1)
+  if (versions.some((v) => v.transactionID === newVersion.transactionID)) {
+    return versions;
+  }
+  return [...versions, newVersion];
+}