fix(gatsby-plugin-gatsby-cloud): emit file nodes after source updates

packages/gatsby-plugin-gatsby-cloud/src/gatsby-node.js

@@ -113,6 +113,7 @@ exports.onPostBuild = async (
   }
 
   await Promise.all([
+    ensureEmittingFileNodesFinished,
     buildHeadersProgram(pluginData, pluginOptions),
     createSiteConfig(pluginData, pluginOptions),
     createRedirects(pluginData, redirects, rewrites),
@@ -156,18 +157,28 @@ const pluginOptionsSchema = function ({ Joi }) {
 
 exports.pluginOptionsSchema = pluginOptionsSchema
 
-exports.onPostBootstrap = async ({ getNodesByType }) => {
-  /**
-   * Emit via IPC absolute paths to files that should be stored
-   */
-  const fileNodes = getNodesByType(`File`)
+/**
+ * We emit File Nodes via IPC and we need to make sure build doesn't finish before all of
+ * messages were sent.
+ */
+let ensureEmittingFileNodesFinished
+exports.onPreBootstrap = ({ emitter, getNodesByType }) => {
+  emitter.on(`API_FINISHED`, action => {
+    if (action.payload.apiName !== `sourceNodes`) {
+      return
+    }
 
-  // TODO: This is missing the cacheLocations .cache/caches + .cache/caches-lmdb
-  let fileNodesEmitted
-  for (const file of fileNodes) {
-    fileNodesEmitted = emitFileNodes({
-      path: file.absolutePath,
-    })
-  }
-  await fileNodesEmitted
+    async function doEmitFileNodes() {
+      const fileNodes = getNodesByType(`File`)
+
+      // TODO: This is missing the cacheLocations .cache/caches + .cache/caches-lmdb
+      for (const file of fileNodes) {
+        await emitFileNodes({
+          path: file.absolutePath,
+        })
+      }
+    }
+
+    ensureEmittingFileNodesFinished = doEmitFileNodes()
+  })
 }

packages/gatsby/src/utils/source-nodes.ts

@@ -112,4 +112,6 @@ export default async ({
   warnForPluginsWithoutNodes(state, nodes)
 
   deleteStaleNodes(state, nodes)
+
+  store.dispatch(actions.apiFinished({ apiName: `sourceNodes` }))
 }