[gatsby-source-contentful]: Add fallback locale support (#5328)

* Add fallback locale support * Fix linting * test: Fix test
gatsbyjs · May 10, 2018 · eb63d28 · eb63d28
1 parent 57db294
commit eb63d28
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Showing 2 changed files with 45 additions and 14 deletions.
diff --git a/packages/gatsby-source-contentful/src/__tests__/normalize.js b/packages/gatsby-source-contentful/src/__tests__/normalize.js
@@ -97,11 +97,17 @@ describe(`Gets field value based on current locale`, () => {
     de: `Playsam Streamliner Klassisches Auto, Espresso`,
     "en-US": `Playsam Streamliner Classic Car, Espresso`,
   }
+  const locales = [
+    { code: `en-US` },
+    { code: `de`, fallbackCode: `en-US` },
+    { code: `gsw_CH`, fallbackCode: `de` },
+  ]
+  const localesFallback = normalize.buildFallbackChain(locales)
   it(`Gets the specified locale`, () => {
     expect(
       normalize.getLocalizedField({
         field,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `en-US`,
         },
@@ -110,7 +116,7 @@ describe(`Gets field value based on current locale`, () => {
     expect(
       normalize.getLocalizedField({
         field,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `de`,
         },
@@ -125,7 +131,7 @@ describe(`Gets field value based on current locale`, () => {
     expect(
       normalize.getLocalizedField({
         field: falseyField,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `en-US`,
         },
@@ -135,7 +141,7 @@ describe(`Gets field value based on current locale`, () => {
     expect(
       normalize.getLocalizedField({
         field: falseyField,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `de`,
         },
@@ -146,7 +152,7 @@ describe(`Gets field value based on current locale`, () => {
     expect(
       normalize.getLocalizedField({
         field,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `gsw_CH`,
           fallbackCode: `de`,
@@ -158,7 +164,7 @@ describe(`Gets field value based on current locale`, () => {
     expect(
       normalize.getLocalizedField({
         field,
-        defaultLocale: `en-US`,
+        localesFallback,
         locale: {
           code: `es-US`,
           fallbackCode: `null`,

diff --git a/packages/gatsby-source-contentful/src/normalize.js b/packages/gatsby-source-contentful/src/normalize.js
@@ -11,20 +11,35 @@ const digest = str =>
 const typePrefix = `Contentful`
 const makeTypeName = type => _.upperFirst(_.camelCase(`${typePrefix} ${type}`))
 
-const getLocalizedField = ({ field, defaultLocale, locale }) => {
+const getLocalizedField = ({ field, locale, localesFallback }) => {
   if (!_.isUndefined(field[locale.code])) {
     return field[locale.code]
-  } else if (!_.isUndefined(field[locale.fallbackCode])) {
-    return field[locale.fallbackCode]
+  } else if (
+    !_.isUndefined(locale.code) &&
+    !_.isUndefined(localesFallback[locale.code])
+  ) {
+    return getLocalizedField({
+      field,
+      locale: { code: localesFallback[locale.code] },
+      localesFallback,
+    })
   } else {
     return null
   }
 }
-
-const makeGetLocalizedField = ({ locale, defaultLocale }) => field =>
-  getLocalizedField({ field, locale, defaultLocale })
+const buildFallbackChain = locales => {
+  const localesFallback = {}
+  _.each(
+    locales,
+    locale => (localesFallback[locale.code] = locale.fallbackCode)
+  )
+  return localesFallback
+}
+const makeGetLocalizedField = ({ locale, localesFallback }) => field =>
+  getLocalizedField({ field, locale, localesFallback })
 
 exports.getLocalizedField = getLocalizedField
+exports.buildFallbackChain = buildFallbackChain
 
 // If the id starts with a number, left-pad it with a c (for Contentful of
 // course :-))
@@ -202,8 +217,13 @@ exports.createContentTypeNodes = ({
 }) => {
   const contentTypeItemId = contentTypeItem.name
   locales.forEach(locale => {
+    const localesFallback = buildFallbackChain(locales)
     const mId = makeMakeId({ currentLocale: locale.code, defaultLocale })
-    const getField = makeGetLocalizedField({ locale, defaultLocale })
+    const getField = makeGetLocalizedField({
+      locale,
+      localesFallback,
+      defaultLocale,
+    })
 
     // Warn about any field conflicts
     const conflictFields = []
@@ -401,8 +421,13 @@ exports.createAssetNodes = ({
   locales,
 }) => {
   locales.forEach(locale => {
+    const localesFallback = buildFallbackChain(locales)
     const mId = makeMakeId({ currentLocale: locale.code, defaultLocale })
-    const getField = makeGetLocalizedField({ locale, defaultLocale })
+    const getField = makeGetLocalizedField({
+      locale,
+      localesFallback,
+      defaultLocale,
+    })
 
     const localizedAsset = { ...assetItem }
     // Create a node for each asset. They may be referenced by Entries