Apollo Client calling every mutation and query twice (React)

Question

Every time I call a query or a mutation It makes two network call and I get to items created. I tried to change the middleware but still getting the same issues. "apollo-cache-inmemory": "^1.2.2", "apollo-client": "^2.3.2", "apollo-link": "^1.2.12", "apollo-link-context": "^1.0.8", "apollo-upload-client": "^11.0.0",

I have tried reducing the middleware and changing some packages but still getting the same issue.

import { ApolloClient } from 'apollo-client'
import { InMemoryCache } from 'apollo-cache-inmemory'
import { appConfig } from 'config'
import { ApolloLink, from } from 'apollo-link'
import { logger } from 'libs/logger'
import { fetchKeyFromSession } from 'libs/session'
import { AUTHENTICATION_TOKEN } from 'constants/index'
import { createUploadLink } from 'apollo-upload-client'

const authMiddleware = new ApolloLink((operation, forward) => {
  logger(
    'GraphQL Interceptor ==>> ',
    operation.query.definitions[0].selectionSet.selections[0].name.value,
    window.location.pathname,
    operation.query.definitions[0].selectionSet.selections[0].arguments,
    window.location.pathname,
    operation.query.definitions[0].selectionSet.selections[0].arguments.map(
      arg => arg && arg.value && arg.value.name.value,
    ),
  )

  operation.setContext({
    headers: {
      Authorization: `Bearer ${fetchKeyFromSession(AUTHENTICATION_TOKEN)}`
    }
  })

  forward(operation).subscribe({
    next: result => logger('Apollo Link Result ==>> ', result),
    error: error => logger('Apollo Link Error ==>> ', error.response),
  })



  return forward(operation)
})


const uploadLink = createUploadLink({ uri: `${appConfig.config.BASE_URL}/api/v1` })

const cache = new InMemoryCache()

const defaultOptions = {
  query: {
    fetchPolicy: 'no-cache',
    errorPolicy: 'all',
  },
}

export const client = new ApolloClient({
  link: from([authMiddleware, uploadLink]),
  cache,
  defaultOptions,
  queryDeduplication: false
})

It's not throwing any error at all but it should call the query/mutation only once not twice. I got two items created in the database due to this.

Answer 1

const authMiddleware = new ApolloLink((operation, forward) => {
  logger(
    'GraphQL Interceptor ==>> ',
    operation.query.definitions[0].selectionSet.selections[0].name.value,
    window.location.pathname,
    operation.query.definitions[0].selectionSet.selections[0].arguments,
    window.location.pathname,
    operation.query.definitions[0].selectionSet.selections[0].arguments.map(
      arg => arg && arg.value && arg.value.name.value,
    ),
  )

  operation.setContext({
    headers: {
      Authorization: `Bearer ${fetchKeyFromSession(AUTHENTICATION_TOKEN)}`
    }
  })

  return forward(operation)
})

The forward(operation).subscribe() is causing the issues remove it, it will started to work fine.

Answer 2

This is an alternative to subscribe:

forward(operation).forEach((data) => {
  data.errors?.forEach((error) => logger('Apollo Link Error ==>> ', error.response));
});