GraphQL查询语法错误

Question

我正在使用此GraphQl nuget通过以下代码在我的系统上实现常规查询

        if (!string.IsNullOrEmpty(query))
        {
            var urlDecode = HttpUtility.UrlDecode(query);

                var result =
                    await (_searchRepository.ExecuteQuery(urlDecode.Replace("\t", "").Replace(@"\", string.Empty))).ConfigureAwait(false);
                response = Request.CreateResponse(HttpStatusCode.OK,
                    new GeneralOutput() {HasError = false, Data = result});

        }
        else
        {
            response = Request.CreateResponse(HttpStatusCode.OK,
                    new GeneralOutput() { HasError = true, Data = null , ErrorType = ErrorType.ValidationError , Message = "Empty Query String"});
        }

执行查询看起来像什么

public async Task<string> ExecuteQuery(string querystring)
{
    try
    {
        var result = await new DocumentExecuter().ExecuteAsync(_ =>
        {
            _.Schema = new Schema { Query = new ViewerType() };
            _.Query = querystring;
        }).ConfigureAwait(false);

        var json = new DocumentWriter(Formatting.None, null).Write(result);
        return json;
    }
    catch (Exception e)
    {
        var logInstance = LogManager.GetCurrentClassLogger();
        logInstance?.Error(e,
            $" {MethodBase.GetCurrentMethod().Name} => {e.Message}{Environment.NewLine}{e.StackTrace}");
        return null;
    }
}

像这样的主要GraqhQL组件

public class ViewerType : ObjectGraphType
{
    public ViewerType()
    {
        Name = "Viewer";
        Field<QueryResult>("MediaSearch",
            arguments: new QueryArguments(
                new QueryArgument<StringGraphType> { Name = "userTwelveDigits", DefaultValue = null},
                new QueryArgument<DateGraphType> { Name = "fromcreationDate", DefaultValue = null },
                new QueryArgument<DateGraphType> { Name = "tocreationDate", DefaultValue = null } ,
                new QueryArgument<StringGraphType> { Name = "mediaId", DefaultValue = null },
                new QueryArgument<IntGraphType> { Name = "versionTypeId", DefaultValue = null },
                new QueryArgument<StringGraphType> { Name = "keyword", DefaultValue = null }

                ),
            resolve: context => (new BaseService<MediaQuery_Result>()).Context.MediaQuery(
                context.GetArgument<string>("userTwelveDigits"),
                context.GetArgument<DateTime?>("fromcreationDate", null),
                context.GetArgument<DateTime?>("tocreationDate", null),
                context.GetArgument<string>("mediaId"),
                context.GetArgument<int?>("versionTypeId", null),
                context.GetArgument<string>("keyword")
            ));
    }

}


  public class QueryResult :  ObjectGraphType<MediaQuery_Result>
    {
        public QueryResult()
        {
            Field(m => m.MediaId).Description("The Media Id");
            Field(m => m.MediaTitle).Description("The Media Title");
            Field(m => m.MediaIdentifier).Description("The Media Identifier");
            Field(m => m.MP4Path).Description("The Media mp4 Path");
            Field(m => m.DataS3Path).Description("The Media S3 Path");
            Field(m => m.InSync.Value).Description("The Media In Sync or not").Name("InSync");
            Field(m => m.IsLinked.Value).Description("The media (video) if linked before or not ").Name("IsLinked");
            Field(m => m.IsPublished.Value).Description("The Media If is published or not ").Name("IsPublished");

        }
    }

我使用了不同的graphql查询字符串，这是行不通的示例

query MediaSearch    
        {

            MediaTitle
            MediaIdentifier
        }
query MediaSearch(userTwelveDigits:"12345678",fromcreationDate:null,tocreationDate:null,mediaId:null,versionTypeId:null,keyword:null)    {  MediaTitle  MediaIdentifier       }

我总是会出错

"{\"errors\":[{\"message\":\"Syntax Error GraphQL (1:19) Expected $, found Name \\\"userTwelveDigits\\\"\\n1: query MediaSearch(userTwelveDigits:\\\"12345678\\\",fromcreationDate:null,tocreationDate:null,mediaId:null,versionTypeId:null,keyword:null)  { MediaTitle MediaIdentifier   }\\n                     ^\\n\"}]}"

任何想法如何解决

Answer 1

这是一个常见错误，它使用GraphQL的“操作名称”作为查询字段，该名称更像修饰函数名称。 这是一个查询，可获取您要的数据：

query MyQueryName {
  MediaSearch {
    MediaTitle
    MediaIdentifier
  }
}

这是您传递参数的方式-它们在现场进行：

query MyQueryName {
  MediaSearch(mediaId: "asdf") {
    MediaTitle
    MediaIdentifier
  }
}

如果您想了解有关GraphQL的更多信息，建议您快速浏览网站上有关查询和模式的“学习”部分： http : //graphql.org/learn/

请注意，上面的MyQueryName可以是任何值，并且完全不影响查询结果。 它仅用于服务器端日志记录，以便您可以轻松识别此查询。

编辑-受此问题的启发，我撰写了有关查询的所有不同部分的博客文章！ https://dev-blog.apollodata.com/the-anatomy-of-a-graphql-query-6dffa9e9e747#.lf93twh8x