How to filter GraphQL query by content language? I am coding Drupal 8/Angular app and Angular is fetching data from Drupal using GraphQL. Everything works fine except now I need to query nodes in a particular language. This is my query:

{
  nodeQuery(filter:
    {conditions: [
      {field: "type", value: "akcia", operator: EQUAL, language: EN},
      {field: "field_datum", value: "2018-02-12T18:00:00", operator: GREATER_THAN_OR_EQUAL}
      {field: "langcode", value: "en", operator: EQUAL}
    ]}
    sort: {field: "field_datum", direction: DESC}
  )
  {
    entities {
      entityLanguage {
        id
      }
      ... on NodeAkcia {
        nid
        langcode {
          value
        }
        title
        fieldDatum {
          value
        }
        body {
          value
        }
        fieldObrazok {
          url
        }
        path {
          alias
          pid
          langcode
          pathauto
        }
      }
    }
  }
}```

Notice the `{field: "langcode", value: "en", operator: EQUAL}` line - that's the best thing I came up with, however, the query returns Slovak version of that node, not the English one.

Is there any better way ho to filter nodes based on their translation?
Your query is almost correct but you need to retrieve the entityTranslation in your entities, something like below for an article in English for example:

 entities {
    ...on NodeArticle {
      entityTranslation(language: EN) {
        entityLabel
      }
    }
  }


See also here for a similar question and answer.