Exception with Multipart File Upload

[jyangtj]

Try to upload multiple files using mutation by following https://github.com/jaydenseric/graphql-multipart-request-spec. It failed with the following exception. Single file upload works fine. Any suggestions?

No serializer found for class java.io.ByteArrayInputStream and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: java.util.ArrayList[0]->org.eclipse.jetty.util.MultiPartInputStreamParser$MultiPart["inputStream"])
java.lang.IllegalArgumentException: No serializer found for class java.io.ByteArrayInputStream and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: java.util.ArrayList[0]->org.eclipse.jetty.util.MultiPartInputStreamParser$MultiPart["inputStream"])
at com.fasterxml.jackson.databind.ObjectMapper._convert(ObjectMapper.java:3750)
at com.fasterxml.jackson.databind.ObjectMapper.convertValue(ObjectMapper.java:3678)
at com.coxautodev.graphql.tools.MethodFieldResolver$createDataFetcher$$inlined$forEachIndexed$lambda$1.invoke(MethodFieldResolver.kt:83)
at com.coxautodev.graphql.tools.MethodFieldResolver$createDataFetcher$$inlined$forEachIndexed$lambda$1.invoke(MethodFieldResolver.kt:23)
at com.coxautodev.graphql.tools.MethodFieldResolverDataFetcher.get(MethodFieldResolver.kt:156)
at graphql.execution.instrumentation.dataloader.DataLoaderDispatcherInstrumentation.lambda$instrumentDataFetcher$0(DataLoaderDispatcherInstrumentation.java:86)
at graphql.execution.ExecutionStrategy.fetchField(ExecutionStrategy.java:261)
at graphql.execution.ExecutionStrategy.resolveFieldWithInfo(ExecutionStrategy.java:202)
at graphql.execution.AsyncExecutionStrategy.execute(AsyncExecutionStrategy.java:70)
at graphql.execution.Execution.executeOperation(Execution.java:159)
at graphql.execution.Execution.execute(Execution.java:101)
at graphql.GraphQL.execute(GraphQL.java:573)
at graphql.GraphQL.parseValidateAndExecute(GraphQL.java:515)
at graphql.GraphQL.executeAsync(GraphQL.java:489)
at graphql.GraphQL.execute(GraphQL.java:420)
at graphql.servlet.GraphQLQueryInvoker.query(GraphQLQueryInvoker.java:95)
at graphql.servlet.GraphQLQueryInvoker.query(GraphQLQueryInvoker.java:91)
at graphql.servlet.GraphQLQueryInvoker.query(GraphQLQueryInvoker.java:42)

[ophelie]

I'm seeing this as well.

This is due to Jackson trying to serialize and deserialize javax.servlet.http.Part objects during value conversion triggered by the data fetcher.

Note that this is only happening when mapping parameters of type List<Part>; when mapping parameters of type Part everything works fine because Jackson fallbacks on a simple casting operation to convert the value, which it cannot do for generic types such as List.

I managed to get my resolver working with this hacky workaround:

• To make the exception go away, declare a no-op custom Jackson serializer for javax.servlet.http.Part
• In the resolver's method, get the parts argument from the DataFetchingEnvironment; environment.getArgument("files")
• You still have to declare the parameter of type List<Part> in your method, but it's value will be empty

@oliemansm What is your recommendation to fix this problem ? In this case the jackson conversion is useless sine the list of part can directly be retrieved from the DataFetchingEnvironment.

[subham28]

Can you share the single file upload code. I am getting the same error in case of single file upload

[alexcibotari]

Hello ,

you can simply add @JsonIgnore annotation to your Part property

@JsonIgnore
private Part file;

in mutation check DataFetchingEnvironment

  public Payload uploadFile(UploadFIleInput input, DataFetchingEnvironment environment) {
    LinkedHashMap<String, Object> ll = environment.getArgument("input");
    Part file = (Part) ll.get("file");
    input.setFile(file);
    return service.uploadFile(input);
  }

and it works with one file

[jakubbrodzinski]

Would you mind sharing working example with me? I get
{"timestamp":"2019-05-19T16:31:05.151+0000","status":415,"error":"Unsupported Media Type","message":"Content type 'multipart/form-data;boundary=------------------------07182a3f39beb5b0;charset=UTF-8' not supported","path":"/graphql"} when I am using CURL to send file to my Mutation.

[jyangtj]

Here is the sample code for single file upload:
Inside schema.graphql, add the following
scalar Upload

type Mutation {
testSingleFileUpload(file: Upload): UploadResult
}

Inside mutation resolver

public UploadResult testSingleFileUpload(Part part, DataFetchingEnvironment env) {
   // use the part parameter to process the uploaded file
}

To test this, post the following form data (we use Postman) to GraphQL endpoint
operations
{ "query": "mutation($file: Upload!) {testSingleFileUpload(file:$file){resultCode}}", "variables": {"file": null } }
map
{"file": ["variables.file"]}
file
chose your file

[subham28]

Hi, In the configuration file you have to add import graphql.schema.GraphQLScalarType; import graphql.servlet.ApolloScalars; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; @configuration public class FileUploadConfig { @bean GraphQLScalarType upload() { return ApolloScalars.Upload; } } and rest all is same as Jack Young code

…

On Mon 20 May, 2019, 08:03 Jack Yang, ***@***.***> wrote: Reopened #240 <#240>. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#240?email_source=notifications&email_token=AFU5IWYIHHNANBB4WV263O3PWIEYPA5CNFSM4GY76XSKYY3PNVWWK3TUL52HS4DFWZEXG43VMVCXMZLOORHG65DJMZUWGYLUNFXW5KTDN5WW2ZLOORPWSZGORQW5ZCA#event-2351815816>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFU5IW7CV4AGLLUU6I5SMRTPWIEYPANCNFSM4GY76XSA> .

[jyangtj]

We are able to work around multi files upload issue based on ophelie's suggestion.

Create a no-op MultiPartSerializer, build the SchemaParserOptions and pass the options to SchemaParser

Inside schema.graphql, add mutation

testMultiFilesUpload(files: [Upload!]!): UploadResult

Inside mutation resolver

public UploadResult testMultiFilesUpload(List<Part> parts, DataFetchingEnvironment env) {
   // get file parts from DataFetchingEnvironment, the parts parameter is not used    
   List<Part> attchmentParts = env.getArgument("files");
    ...  
 }

Post the following form data to your graphql endpoint
operations
{ "query": "mutation($files:[Upload!]!) {testMultiFilesUpload(files:$files){resultCode}}", "variables": {"files": [null, null] } }
map
{ "file0": ["variables.files.0"] , "file1":["variables.files.1"]}
file0
your file
file1
your file