From 4b49b83b138415c3e8e7454f0f2a4176de9af3df Mon Sep 17 00:00:00 2001
From: John Chilton <jmchilton@gmail.com>
Date: Tue, 24 Oct 2023 22:36:52 -0400
Subject: [PATCH] Fix GQL infinite scrolling in tool shed.

---
 lib/tool_shed/webapp/frontend/src/apollo.ts   | 12 +++-
 .../src/components/RepositoriesForOwner.vue   | 39 ++++--------
 .../src/components/RepositoriesGrid.vue       | 25 +-------
 .../pages/RepositoriesByCategory.vue          | 43 +++++--------
 .../webapp/frontend/src/relayClient.ts        | 63 +++++++++++++++++++
 5 files changed, 103 insertions(+), 79 deletions(-)
 create mode 100644 lib/tool_shed/webapp/frontend/src/relayClient.ts

diff --git a/lib/tool_shed/webapp/frontend/src/apollo.ts b/lib/tool_shed/webapp/frontend/src/apollo.ts
index 572617f52fc8..b43a3bb3eda7 100644
--- a/lib/tool_shed/webapp/frontend/src/apollo.ts
+++ b/lib/tool_shed/webapp/frontend/src/apollo.ts
@@ -1,6 +1,15 @@
 import { createApolloProvider } from "@vue/apollo-option"
 import { ApolloClient, InMemoryCache, DefaultOptions } from "@apollo/client/core"
 
+import { loadErrorMessages, loadDevMessages } from "@apollo/client/dev"
+
+const dev = false
+if (dev) {
+    // Adds messages only in a dev environment
+    loadDevMessages()
+    loadErrorMessages()
+}
+
 const defaultOptions: DefaultOptions = {
     watchQuery: {
         fetchPolicy: "no-cache",
@@ -12,9 +21,10 @@ const defaultOptions: DefaultOptions = {
     },
 }
 
+export const cache = new InMemoryCache()
 export const apolloClient = new ApolloClient({
     uri: "/api/graphql/",
-    cache: new InMemoryCache(),
+    cache: cache,
     defaultOptions: defaultOptions,
 })
 
diff --git a/lib/tool_shed/webapp/frontend/src/components/RepositoriesForOwner.vue b/lib/tool_shed/webapp/frontend/src/components/RepositoriesForOwner.vue
index 28fe8e1f8b35..5db3578ca516 100644
--- a/lib/tool_shed/webapp/frontend/src/components/RepositoriesForOwner.vue
+++ b/lib/tool_shed/webapp/frontend/src/components/RepositoriesForOwner.vue
@@ -5,7 +5,8 @@ import { nodeToRow } from "@/components/RepositoriesGridInterface"
 import ErrorBanner from "@/components/ErrorBanner.vue"
 import LoadingDiv from "@/components/LoadingDiv.vue"
 import { graphql } from "@/gql"
-import { useQuery } from "@vue/apollo-composable"
+import type { Query, RelayRepositoryConnection } from "@/gql/graphql"
+import { useRelayInfiniteScrollQuery } from "@/relayClient"
 
 interface RepositoriesByOwnerProps {
     username: string
@@ -30,34 +31,18 @@ const query = graphql(/* GraphQL */ `
     }
 `)
 
-async function onScroll(): Promise<void> {
-    const cursor = result.value?.relayRepositoriesForOwner?.pageInfo.endCursor || null
-    fetchMore({
-        variables: {
-            username: props.username,
-            cursor: cursor,
-        },
-        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-        // @ts-ignore
-        updateQuery: (previousResult, { fetchMoreResult }) => {
-            const newRepos = fetchMoreResult?.relayRepositoriesForOwner?.edges || []
-            const edges = [...(previousResult?.relayRepositoriesForOwner?.edges || []), ...newRepos]
-            const pageInfo = { ...fetchMoreResult?.relayRepositoriesForOwner?.pageInfo }
-            return {
-                relayRepositoriesForOwner: {
-                    __typename: fetchMoreResult?.relayRepositoriesForOwner?.__typename,
-                    // Merging the tag list
-                    edges: edges,
-                    pageInfo: pageInfo,
-                },
-            }
-        },
-    })
+function toResult(queryResult: Query): RelayRepositoryConnection {
+    const result = queryResult.relayRepositoriesForOwner
+    if (!result) {
+        throw Error("problem")
+    }
+    return result as RelayRepositoryConnection
 }
-const { result, loading, error, fetchMore } = useQuery(query, { username: props.username })
+
+const { records, error, loading, onScroll } = useRelayInfiniteScrollQuery(query, { username: props.username }, toResult)
+
 const rows = computed(() => {
-    const nodes = result.value?.relayRepositoriesForOwner?.edges.map((v) => v?.node)
-    return nodes?.map(nodeToRow) || []
+    return records.value.map(nodeToRow)
 })
 </script>
 <template>
diff --git a/lib/tool_shed/webapp/frontend/src/components/RepositoriesGrid.vue b/lib/tool_shed/webapp/frontend/src/components/RepositoriesGrid.vue
index 7cba807d69db..fd8ed9104b7a 100644
--- a/lib/tool_shed/webapp/frontend/src/components/RepositoriesGrid.vue
+++ b/lib/tool_shed/webapp/frontend/src/components/RepositoriesGrid.vue
@@ -57,7 +57,7 @@ const columns = computed(() => {
 
 const tableLoading = ref(false)
 
-async function onScroll(details: ScrollDetails) {
+async function onVirtualScroll(details: ScrollDetails) {
     console.log(details)
     const { to, direction } = details
     if (direction == "decrease") {
@@ -95,7 +95,7 @@ const adaptedRows = computed(() =>
             :pagination="pagination"
             :rows-per-page-options="[0]"
             :no-data-label="noDataLabel"
-            @virtual-scroll="onScroll"
+            @virtual-scroll="onVirtualScroll"
             hide-header
             hide-bottom
         >
@@ -122,27 +122,6 @@ const adaptedRows = computed(() =>
                 </q-tr>
             </template>
         </q-table>
-        <!--
-        <q-table
-            v-if="loading || rows.length > 0"
-            style="height: 90vh"
-            :title="title"
-            :rows="rows"
-            :columns="columns"
-            :loading="tableLoading"
-            row-key="index"
-            virtual-scroll
-            :virtual-scroll-item-size="48"
-            :virtual-scroll-sticky-size-start="48"
-            :pagination="pagination"
-            :rows-per-page-options="[0]"
-            :no-data-label="noDataLabel"
-            @virtual-scroll="onScroll"
-            hide-header
-            hide-bottom
-        >
-        </q-table>
-        -->
         <q-banner rounded class="bg-warning text-white" v-else>
             <!-- the no-data-label doesn't seem to be working,
                  probably because we're overriding the whole body
diff --git a/lib/tool_shed/webapp/frontend/src/components/pages/RepositoriesByCategory.vue b/lib/tool_shed/webapp/frontend/src/components/pages/RepositoriesByCategory.vue
index b57b82ecc98a..868415b47241 100644
--- a/lib/tool_shed/webapp/frontend/src/components/pages/RepositoriesByCategory.vue
+++ b/lib/tool_shed/webapp/frontend/src/components/pages/RepositoriesByCategory.vue
@@ -6,8 +6,8 @@ import { nodeToRow } from "@/components/RepositoriesGridInterface"
 import ErrorBanner from "@/components/ErrorBanner.vue"
 import LoadingDiv from "@/components/LoadingDiv.vue"
 import { graphql } from "@/gql"
-import { useQuery } from "@vue/apollo-composable"
-
+import type { Query, RelayRepositoryConnection } from "@/gql/graphql"
+import { useRelayInfiniteScrollQuery } from "@/relayClient"
 const categoriesStore = useCategoriesStore()
 
 const props = defineProps({
@@ -45,35 +45,22 @@ const query = graphql(/* GraphQL */ `
     }
 `)
 
-async function onScroll(): Promise<void> {
-    const cursor = result.value?.relayRepositoriesForCategory?.pageInfo.endCursor || null
-    fetchMore({
-        variables: {
-            categoryId: props.categoryId,
-            cursor: cursor,
-        },
-        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-        // @ts-ignore
-        updateQuery: (previousResult, { fetchMoreResult }) => {
-            const newRepos = fetchMoreResult?.relayRepositoriesForCategory?.edges || []
-            const edges = [...(previousResult?.relayRepositoriesForCategory?.edges || []), ...newRepos]
-            const pageInfo = { ...fetchMoreResult?.relayRepositoriesForCategory?.pageInfo }
-            return {
-                relayRepositoriesForCategory: {
-                    __typename: fetchMoreResult?.relayRepositoriesForCategory?.__typename,
-                    // Merging the tag list
-                    edges: edges,
-                    pageInfo: pageInfo,
-                },
-            }
-        },
-    })
+function toResult(queryResult: Query): RelayRepositoryConnection {
+    const result = queryResult.relayRepositoriesForCategory
+    if (!result) {
+        throw Error("problem")
+    }
+    return result as RelayRepositoryConnection
 }
 
-const { result, loading, error, fetchMore } = useQuery(query, { categoryId: props.categoryId })
+const { records, error, loading, onScroll } = useRelayInfiniteScrollQuery(
+    query,
+    { categoryId: props.categoryId },
+    toResult
+)
+
 const rows = computed(() => {
-    const nodes = result.value?.relayRepositoriesForCategory?.edges.map((v) => v?.node)
-    return nodes?.map(nodeToRow) || []
+    return records.value.map(nodeToRow)
 })
 </script>
 <template>
diff --git a/lib/tool_shed/webapp/frontend/src/relayClient.ts b/lib/tool_shed/webapp/frontend/src/relayClient.ts
new file mode 100644
index 000000000000..ba9d4bfc61d1
--- /dev/null
+++ b/lib/tool_shed/webapp/frontend/src/relayClient.ts
@@ -0,0 +1,63 @@
+import { ref, type Ref } from "vue"
+import type { OperationVariables } from "@apollo/client/core/index.js"
+import { useLazyQuery } from "@vue/apollo-composable"
+import { DocumentParameter } from "@vue/apollo-composable/dist/useQuery"
+import type { Maybe, PageInfo } from "@/gql/graphql"
+
+export interface InterfaceHasNode<NodeType> {
+    node?: Maybe<NodeType>
+}
+
+export interface RelayQuery<NodeType> {
+    pageInfo: PageInfo
+    edges: Array<Maybe<InterfaceHasNode<NodeType>>>
+}
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+export function useRelayInfiniteScrollQuery<ResultType, NodeType>(
+    query: DocumentParameter<any, OperationVariables>,
+    variables: OperationVariables,
+    toResult: (arg: ResultType) => RelayQuery<NodeType>
+) {
+    const records = ref<NodeType[]>([]) as Ref<Array<NodeType>>
+    const lastResult = ref<ResultType | null>(null) as Ref<ResultType | null>
+    const hasNextPage = ref(true)
+
+    const { load, error, loading, fetchMore } = useLazyQuery(query, variables, {
+        fetchPolicy: "network-only",
+        nextFetchPolicy: "network-only",
+    })
+
+    function handleResult(result: ResultType) {
+        lastResult.value = result
+        const asResult: RelayQuery<NodeType> = toResult(result)
+        hasNextPage.value = asResult.pageInfo.hasNextPage
+        const nodes: NodeType[] = asResult.edges.flatMap((x) => (x && x.node ? [x.node] : []))
+        records.value.push(...nodes)
+    }
+
+    async function onScroll() {
+        if (hasNextPage.value && lastResult.value != null && fetchMore != null) {
+            const asResult: RelayQuery<NodeType> = toResult(lastResult.value)
+            const endCursor = asResult.pageInfo.endCursor
+            const fetchMoreVariables = { ...variables, cursor: endCursor }
+            const fetchMorePromise = fetchMore({
+                variables: fetchMoreVariables,
+                /*
+                fetchPolicy: "network-only",
+                nextFetchPolicy: "network-only",
+                */
+            })
+            if (fetchMorePromise) {
+                fetchMorePromise.then((result) => handleResult(result.data as ResultType))
+            }
+        }
+    }
+
+    const loadPromise = load()
+    if (loadPromise) {
+        loadPromise.then(handleResult)
+    }
+
+    return { records, error, loading, onScroll }
+}