feat: pass feature flags down to netlify build on dev (#6291)

Author: Lukas Holzer

src/lib/build.ts

@@ -5,7 +5,7 @@ import build from '@netlify/build'
 // @ts-expect-error TS(7016) FIXME: Could not find a declaration file for module 'toml... Remove this comment to see the full error message
 import tomlify from 'tomlify-j0.4'
 
-import { isFeatureFlagEnabled } from '../utils/feature-flags.js'
+import { getFeatureFlagsFromSiteInfo } from '../utils/feature-flags.js'
 
 import { getBootstrapURL } from './edge-functions/bootstrap.js'
 import { featureFlags as edgeFunctionsFeatureFlags } from './edge-functions/consts.js'
@@ -93,17 +93,6 @@ export const getBuildOptions = ({
   }
 }
 
-/**
- * @param {*} siteInfo
- * @returns {Record<string, any>}
- */
-// @ts-expect-error TS(7006) FIXME: Parameter 'siteInfo' implicitly has an 'any' type.
-const getFeatureFlagsFromSiteInfo = (siteInfo) => ({
-  ...siteInfo.feature_flags,
-  // see https://github.com/netlify/pod-dev-foundations/issues/581#issuecomment-1731022753
-  zisi_golang_use_al2: isFeatureFlagEnabled('cli_golang_use_al2', siteInfo),
-})
-
 /**
  * run the build command
  * @param {BuildConfig} options

src/utils/feature-flags.ts

@@ -13,3 +13,14 @@
 // @ts-expect-error TS(7006) FIXME: Parameter 'flagName' implicitly has an 'any' type.
 export const isFeatureFlagEnabled = (flagName: string, siteInfo): boolean =>
   Boolean(siteInfo.feature_flags && siteInfo.feature_flags[flagName] !== false)
+
+/**
+ * Retrieves all Feature flags from the siteInfo
+ */
+export const getFeatureFlagsFromSiteInfo = (siteInfo: {
+  feature_flags?: Record<string, boolean | string | number>
+}): Record<string, boolean | string | number> => ({
+  ...(siteInfo.feature_flags || {}),
+  // see https://github.com/netlify/pod-dev-foundations/issues/581#issuecomment-1731022753
+  zisi_golang_use_al2: isFeatureFlagEnabled('cli_golang_use_al2', siteInfo),
+})

src/utils/run-build.ts

@@ -8,6 +8,7 @@ import { getPathInProject } from '../lib/settings.js'
 import { error } from './command-helpers.js'
 import { startFrameworkServer } from './framework-server.js'
 import { INTERNAL_FUNCTIONS_FOLDER } from './functions/index.js'
+import { getFeatureFlagsFromSiteInfo } from './feature-flags.js'
 
 const netlifyBuildPromise = import('@netlify/build')
 
@@ -71,6 +72,7 @@ export const runNetlifyBuild = async ({ command, env = {}, options, settings, ti
     mode: 'cli',
     telemetry: false,
     buffer: false,
+    featureFlags: getFeatureFlagsFromSiteInfo(cachedConfig.siteInfo),
     offline: options.offline,
     packagePath: command.workspacePackage,
     cwd: cachedConfig.buildDir,