feat(contentful): warn users when using restricted content type names (#30715)

* feat(contentful): warn users when using restricted content type names. Closes #30089

* docs(contentful): inform about field and content type name limitations

Author: axe312ger

packages/gatsby-source-contentful/README.md

@@ -29,6 +29,10 @@ This plugin has several limitations, please be aware of these:
 
 4. Using the preview functionallity might result in broken content over time, as syncing data on preview is not officially supported by Contentful. Make sure to regulary clean your cache when using Contentfuls preview API.
 
+5. The following content type names are not allowed: `entity`, `reference`
+
+6. The following field names are restricted and will be prefixed: `children`, `contentful_id`, `fields`, `id`, `internal`, `parent`,
+
 ### Using Delivery API
 
 ```javascript

packages/gatsby-source-contentful/src/__fixtures__/restricted-content-type.js

@@ -0,0 +1,78 @@
+exports.initialSync = () => {
+  return {
+    currentSyncData: {
+      entries: [],
+      assets: [],
+      deletedEntries: [],
+      deletedAssets: [],
+      nextSyncToken: `12345`,
+    },
+    contentTypeItems: [
+      {
+        sys: {
+          space: {
+            sys: {
+              type: `Link`,
+              linkType: `Space`,
+              id: `uzfinxahlog0`,
+              contentful_id: `uzfinxahlog0`,
+            },
+          },
+          id: `reference`,
+          type: `ContentType`,
+          createdAt: `2020-06-03T14:17:18.696Z`,
+          updatedAt: `2020-06-03T14:17:18.696Z`,
+          environment: {
+            sys: {
+              id: `master`,
+              type: `Link`,
+              linkType: `Environment`,
+            },
+          },
+          revision: 1,
+          contentful_id: `person`,
+        },
+        displayField: `name`,
+        name: `Reference`,
+        description: ``,
+        fields: [
+          {
+            id: `name`,
+            name: `Name`,
+            type: `Symbol`,
+            localized: false,
+            required: true,
+            disabled: false,
+            omitted: false,
+          },
+        ],
+      },
+    ],
+    defaultLocale: `en-US`,
+    locales: [
+      {
+        code: `en-US`,
+        name: `English (United States)`,
+        default: true,
+        fallbackCode: null,
+        sys: {
+          id: `1uSElBQA68GRKF30tpTxxT`,
+          type: `Locale`,
+          version: 1,
+        },
+      },
+    ],
+    space: {
+      sys: { type: `Space`, id: `uzfinxahlog0` },
+      name: `Starter Gatsby Blog`,
+      locales: [
+        {
+          code: `en-US`,
+          default: true,
+          name: `English (United States)`,
+          fallbackCode: null,
+        },
+      ],
+    },
+  }
+}

packages/gatsby-source-contentful/src/__tests__/gatsby-node.js

@@ -13,6 +13,7 @@ const normalize = require(`../normalize`)
 
 const startersBlogFixture = require(`../__fixtures__/starter-blog-data`)
 const richTextFixture = require(`../__fixtures__/rich-text-data`)
+const restrictedContentTypeFixture = require(`../__fixtures__/restricted-content-type`)
 
 const pluginOptions = { spaceId: `testSpaceId` }
 
@@ -742,4 +743,38 @@ describe(`gatsby-node`, () => {
       })
     )
   })
+
+  it(`panics when response contains restricted content types`, async () => {
+    cache.get.mockClear()
+    cache.set.mockClear()
+    fetch.mockImplementationOnce(restrictedContentTypeFixture.initialSync)
+
+    const mockPanicReporter = {
+      ...reporter,
+      panic: jest.fn(),
+    }
+
+    await gatsbyNode.sourceNodes(
+      {
+        actions,
+        store,
+        getNodes,
+        getNode,
+        reporter: mockPanicReporter,
+        createNodeId,
+        cache,
+        getCache,
+        schema,
+      },
+      pluginOptions
+    )
+
+    expect(mockPanicReporter.panic).toBeCalledWith(
+      expect.objectContaining({
+        context: {
+          sourceMessage: `Restricted ContentType name found. The name "reference" is not allowed.`,
+        },
+      })
+    )
+  })
 })

packages/gatsby-source-contentful/src/gatsby-node.js

@@ -24,6 +24,8 @@ const restrictedNodeFields = [
   `parent`,
 ]
 
+const restrictedContentTypes = [`entity`, `reference`]
+
 exports.setFieldsOnGraphQLNodeType = require(`./extend-node-type`).extendNodeType
 
 const validateContentfulAccess = async pluginOptions => {
@@ -311,6 +313,30 @@ exports.sourceNodes = async (
     }
   }
 
+  // Check for restricted content type names
+  const useNameForId = pluginConfig.get(`useNameForId`)
+
+  contentTypeItems.forEach(contentTypeItem => {
+    // Establish identifier for content type
+    //  Use `name` if specified, otherwise, use internal id (usually a natural-language constant,
+    //  but sometimes a base62 uuid generated by Contentful, hence the option)
+    let contentTypeItemId
+    if (useNameForId) {
+      contentTypeItemId = contentTypeItem.name.toLowerCase()
+    } else {
+      contentTypeItemId = contentTypeItem.sys.id.toLowerCase()
+    }
+
+    if (restrictedContentTypes.includes(contentTypeItemId)) {
+      reporter.panic({
+        id: CODES.FetchContentTypes,
+        context: {
+          sourceMessage: `Restricted ContentType name found. The name "${contentTypeItemId}" is not allowed.`,
+        },
+      })
+    }
+  })
+
   const allLocales = locales
   locales = locales.filter(pluginConfig.get(`localeFilter`))
   reporter.verbose(