Insomnia GraphQL File Upload Scalar

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Uploading a File with Upload Scalar and Insomnia

Uploading a File with “Upload” Scalar isn’t a big problem if you are using library like graphql-upload. But if you like just to try/simulate it with Insomnia, you need to know what happens under to hood.
In fact, you will send a multipart form request to the GraphQL server.

It is split in three parts (be careful, naming is important):

  • operations, which contains the GraphQL query and variables
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{
  "query": "mutation($comment: String!  $file: Upload!) {  
    uploadFile(comment: $comment, file: $file) {
      id,
      success
    }}",
  "variables": {
    "comment": "Just a comment",
    "file": null
  }
}
  • map, which maps the file you would like to upload 0, with the GraphQL variable name file
    • You can extend it, if you like to upload multiple files
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{"0":["variables.file"]}
  • 0, refers to the file, which you selected and would like to upload

Note: operations and map has the type “Text (Multi-line)” and not “File”.