actually enable query on demand

gatsbyjs · Nov 17, 2020 · 10ca94e · 10ca94e
1 parent d0fe1ee
commit 10ca94e
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Showing 4 changed files with 60 additions and 2 deletions.
diff --git a/packages/gatsby/cache-dir/dev-loader.js b/packages/gatsby/cache-dir/dev-loader.js
@@ -77,6 +77,9 @@ class DevLoader extends BaseLoader {
   }
 
   doPrefetch(pagePath) {
+    if (process.env.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND) {
+      return Promise.resolve()
+    }
     return super.doPrefetch(pagePath).then(result => result.payload)
   }
 

diff --git a/packages/gatsby/src/services/calculate-dirty-queries.ts b/packages/gatsby/src/services/calculate-dirty-queries.ts
@@ -5,11 +5,48 @@ import { assertStore } from "../utils/assert-store"
 
 export async function calculateDirtyQueries({
   store,
+  websocketManager,
+  currentlyHandledPendingQueryRuns,
 }: Partial<IQueryRunningContext>): Promise<{
   queryIds: IGroupedQueryIds
 }> {
   assertStore(store)
   const state = store.getState()
   const queryIds = calcDirtyQueryIds(state)
-  return { queryIds: groupQueryIds(queryIds) }
+
+  let queriesToRun: Array<string> = queryIds
+
+  if (
+    process.env.gatsby_executing_command === `develop` &&
+    process.env.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND
+  ) {
+    // 404 are special cases in our runtime that ideally use
+    // generic things to work, but for now they have special handling
+    const pagePathFilter = new Set([`/404.html`, `/dev-404-page/`])
+
+    // we want to make sure we run queries for pages that user currently
+    // view in the browser
+    if (websocketManager?.activePaths) {
+      websocketManager.activePaths.forEach(
+        pagePathFilter.add.bind(pagePathFilter)
+      )
+    }
+
+    // we also want to make sure we include pages that were requested from
+    // via `page-data` fetches or websocket requests
+    if (currentlyHandledPendingQueryRuns) {
+      currentlyHandledPendingQueryRuns.forEach(
+        pagePathFilter.add.bind(pagePathFilter)
+      )
+    }
+
+    // static queries are also not on demand
+    queriesToRun = queryIds.filter(
+      queryId => queryId.startsWith(`sq--`) || pagePathFilter.has(queryId)
+    )
+  }
+
+  return {
+    queryIds: groupQueryIds(queriesToRun),
+  }
 }
diff --git a/packages/gatsby/src/services/initialize.ts b/packages/gatsby/src/services/initialize.ts
@@ -1,5 +1,5 @@
 import _ from "lodash"
-import { slash } from "gatsby-core-utils"
+import { slash, isCI } from "gatsby-core-utils"
 import fs from "fs-extra"
 import md5File from "md5-file"
 import crypto from "crypto"
@@ -162,6 +162,21 @@ export async function initialize({
 
   activity.end()
 
+  if (
+    process.env.gatsby_executing_command === `develop` &&
+    process.env.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND
+  ) {
+    if (isCI()) {
+      process.env.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND = undefined
+      reporter.warn(
+        `Experimental Query on Demand feature is not available in CI environment. Continuing with regular mode.`
+      )
+    } else {
+      reporter.info(`Using experimental Query on Demand feature`)
+      telemetry.trackFeatureIsUsed(`QueryOnDemand`)
+    }
+  }
+
   // run stale jobs
   store.dispatch(removeStaleJobs(store.getState()))
 

diff --git a/packages/gatsby/src/utils/webpack.config.js b/packages/gatsby/src/utils/webpack.config.js
@@ -85,6 +85,9 @@ module.exports = async (
     envObject.PUBLIC_DIR = JSON.stringify(`${process.cwd()}/public`)
     envObject.BUILD_STAGE = JSON.stringify(stage)
     envObject.CYPRESS_SUPPORT = JSON.stringify(process.env.CYPRESS_SUPPORT)
+    envObject.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND = JSON.stringify(
+      !!process.env.GATSBY_EXPERIMENTAL_QUERY_ON_DEMAND
+    )
 
     if (stage === `develop`) {
       envObject.GATSBY_SOCKET_IO_DEFAULT_TRANSPORT = JSON.stringify(