Replace the domain for all image blocks in a post (to use a CDN)

query InitializeEmptyVariables {
  emptyArray: _echo(value: [])
    @export(as: "coreImageURLItems")
    @export(as: "coreImageURLReplacementsFrom")
    @export(as: "coreImageURLReplacementsTo")
    @remove
}
 
# Extract all the image URLs from the `core/image` blocks, and export them under `$coreImageURLItems`
query FetchData(
  $postID: ID!
  $domain: String!
  $cdnDomain: String!
)
  @configureWarningsOnExportingDuplicateVariable(enabled: false)
  @depends(on: "InitializeEmptyVariables")
{
  post(by: { id: $postID }, status: any ) {
    rawContent
      @export(as: "rawContent")
 
    coreImage: blockFlattenedDataItems(
      filterBy: { include: "core/image" }
    )
      @underEachArrayItem
        @underJSONObjectProperty(
          by: { key: "attributes" }
        )
          @underJSONObjectProperty(
            by: { key: "url" }
            failIfNonExistingKeyOrPath: false
          )
            @export(
              as: "coreImageURLItems"
            )
  }
  
  searchRegex: _sprintf(
    string: "#^https?://%s/(.*)\\.(jpe?g|png|gif|avif|webp)$#",
    values: [$domain]
  )
    @export(as: "searchRegex")
    
  replaceWith: _sprintf(
    string: "https://%s/$1.$2",
    values: [$cdnDomain]
  )
    @export(as: "replaceWith")
}
 
# Convert the URLs and place the results under `$transformations`
query TransformData
  @depends(on: "FetchData")
{
  transformations: _echo(value: {
    coreImageURL: {
      from: $coreImageURLItems,
      to: $coreImageURLItems,
    },
  })
    @underEachJSONObjectProperty
      @underJSONObjectProperty(by: { key: "to" })
        @underEachArrayItem
          @strRegexReplace(
            searchRegex: $searchRegex,
            replaceWith: $replaceWith
          )
    @export(as: "transformations")
}
 
# Escape the regex patterns and their replacements
query EscapeRegexStrings
  @depends(on: "TransformData")
{  
  escapedRegexStrings: _echo(value: $transformations)
    @underEachJSONObjectProperty
      @underJSONObjectProperty(by: { key: "from" })
        @underEachArrayItem
          @strQuoteRegex
    @underEachJSONObjectProperty
      @underJSONObjectProperty(
        by: { key: "to" }
        affectDirectivesUnderPos: [1, 3],
      )
        @underEachArrayItem
          @strRegexReplace(
            searchRegex: "#\\$(\\d+)#",
            replaceWith: "\\\\\\$1"
          )
        @underEachArrayItem(
          passValueOnwardsAs: "value"
        )
          @applyField(
            name: "_sprintf",
            arguments: {
              string: "$1%s$2",
              values: [$value]
            },
            setResultInResponse: true
          )
    @export(as: "escapedRegexTransformations")
}
 
# Generate the regex patterns, and assign them to `$coreImageURLReplacementsFrom`
query CreateRegexReplacements
  @depends(on: "EscapeRegexStrings")
{  
  regexReplacements: _echo(value: $escapedRegexTransformations)
    @underJSONObjectProperty(
      by: { key: "coreImageURL" }
      affectDirectivesUnderPos: [1, 5]
    )
      @underJSONObjectProperty(
        by: { key: "from" }
        affectDirectivesUnderPos: [1, 3],
      )
        @underEachArrayItem(
          passValueOnwardsAs: "value"
        )
          @applyField(
            name: "_sprintf",
            arguments: {
              string: "#(<!-- wp:image .*?-->\\n?.*<img .*?src=\\\")%s(\\\".*>.*\\n?<!-- /wp:image -->)#",
              values: [$value]
            },
            setResultInResponse: true
          )
        @export(
          as: "coreImageURLReplacementsFrom",
        )
      @underJSONObjectProperty(
        by: { key: "to" }
      )
        @export(
          as: "coreImageURLReplacementsTo",
        )
}
 
# Execute the regex search and replace, export the results under `$transformedRawContent`
query ExecuteRegexReplacements
  @depends(on: "CreateRegexReplacements")
{  
  transformedRawContent: _echo(value: $rawContent)
    @strRegexReplaceMultiple(
      limit: 1,
      searchRegex: $coreImageURLReplacementsFrom,
      replaceWith: $coreImageURLReplacementsTo
    )
    
    @export(as: "transformedRawContent")
}
 
# Execute the mutation to update the post
mutation ReplaceDomainOnPostCoreImageBlocksToUseCDN($postID: ID!)
  @depends(on: "ExecuteRegexReplacements")
{
  updatePost(input: {
    id: $postID,
    contentAs: {
      html: $transformedRawContent
    }
  }) {
    status
    errors {
      __typename
      ...on ErrorPayload {
        message
      }
    }
    post {
      id
      title
      rawContent
    }    
  }
}Copy