fix(gatsby-source-contentful): Correct supported image formats (#29562)

Author: ascorbic

packages/gatsby-plugin-image/src/resolver-utils.ts

@@ -176,7 +176,7 @@ export function getGatsbyImageFieldConfig<TSource, TContext>(
             The image formats to generate. Valid values are AUTO (meaning the same format as the source image), JPG, PNG, WEBP and AVIF.
             The default value is [AUTO, WEBP], and you should rarely need to change this. Take care if you specify JPG or PNG when you do
             not know the formats of the source images, as this could lead to unwanted results such as converting JPEGs to PNGs. Specifying
-            both PNG and JPG is not supported and will be ignored. AVIF support is currently experimental.
+            both PNG and JPG is not supported and will be ignored. 
         `,
         defaultValue: [`auto`, `webp`],
       },

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

@@ -12,6 +12,7 @@ const {
   GraphQLFloat,
   GraphQLNonNull,
   GraphQLJSON,
+  GraphQLList,
 } = require(`gatsby/graphql`)
 const qs = require(`qs`)
 const { generateImageData } = require(`gatsby-plugin-image`)
@@ -33,6 +34,8 @@ const {
 // cache is more likely to go stale than the images (which never go stale)
 // Note that the same image might be requested multiple times in the same run
 
+const validImageFormats = new Set([`jpg`, `png`, `webp`])
+
 if (process.env.GATSBY_REMOTE_CACHE) {
   console.warn(
     `Note: \`GATSBY_REMOTE_CACHE\` will be removed soon because it has been renamed to \`GATSBY_CONTENTFUL_EXPERIMENTAL_REMOTE_CACHE\``
@@ -200,6 +203,13 @@ const generateImageSource = (
     height = CONTENTFUL_IMAGE_MAX_SIZE
   }
 
+  if (!validImageFormats.has(toFormat)) {
+    console.warn(
+      `[gatsby-source-contentful] Invalid image format "${toFormat}". Supported types are jpg, png and webp"`
+    )
+    return undefined
+  }
+
   const src = createUrl(filename, {
     width,
     height,
@@ -781,6 +791,16 @@ exports.extendNodeType = ({ type, store, reporter }) => {
         type: GraphQLInt,
         defaultValue: 50,
       },
+      formats: {
+        type: GraphQLList(ImageFormatType),
+        description: stripIndent`
+            The image formats to generate. Valid values are AUTO (meaning the same format as the source image), JPG, PNG, and WEBP.
+            The default value is [AUTO, WEBP], and you should rarely need to change this. Take care if you specify JPG or PNG when you do
+            not know the formats of the source images, as this could lead to unwanted results such as converting JPEGs to PNGs. Specifying
+            both PNG and JPG is not supported and will be ignored. 
+        `,
+        defaultValue: [``, `webp`],
+      },
     })
 
     fieldConfig.type = GraphQLJSON

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

@@ -4,6 +4,7 @@ const ImageFormatType = new GraphQLEnumType({
   name: `ContentfulImageFormat`,
   values: {
     NO_CHANGE: { value: `` },
+    AUTO: { value: `` },
     JPG: { value: `jpg` },
     PNG: { value: `png` },
     WEBP: { value: `webp` },