Azure Cosmos Pagination: FeedResponse.ContinuationToken not working in the next request

Question

below is the code that I do pagination in Azure Cosmos. In that function I return the ContinuationToken of the FeedResponse. The first request to get the first page is fine and it return the Continuation Token. However if I used that token in the next request then the API return error 500.

I also notice that the ContinuationToken return from FeedRespone seem like in Json format like that. I have tried to get the token section only, or even copy the whole json but no cigar though

"nextToken": "[{"token":"+RID:~UVURALkfIb4FAAAAAAAAAA==#RT:1#TRC:3#RTD:hCgamV5sp6dv/pVR3z0oBTMxMzIuMTQuNDFVMTY7MjY7NDIvOTk3MzIxMlsA#ISV:2#IEO:65567#QCF:1#FPC:AQEAAAAAAAAACAAAAAAAAAA=","range":{"min":"","max":"FF"}}]"

Response from the First Page with Token return Enter Return Token to next request and error 500

Function Code

public virtual async Task<(IEnumerable<TDomain>, string token)> ListAsync(List<ISpecification<TEntity>> specifications, PageOptions pageOptions, CancellationToken cancellationToken)
        {
            var container = await GetContainer(cancellationToken);
            string token = null;
            var result = new List<TDomain>();
            QueryRequestOptions options = new QueryRequestOptions()
            {
                MaxItemCount = pageOptions.MaxResults
            };
            options.MaxItemCount = pageOptions.MaxResults;
            try
            {

                var query = container
                    .GetItemLinqQueryable<TEntity>(false, pageOptions.NextToken, options)
                    .Specify(specifications);

                var iterator = _cosmosLinqQuery.GetFeedIterator(query);

     
                    var response = await iterator.ReadNextAsync(cancellationToken);
                    token = response.ContinuationToken; // return a token
                    foreach (var item in response)
                    {
                        var mapped = _mapper.ToDomain(item);
                        result.Add(mapped);
                    }
      
            }
            catch (Exception ex)
            {
                var exception = new DataAccessException("Unexpected error while listing items", ex);
                exception.Data["ContainerName"] = ContainerName;
                throw exception;
            }

            return (result,token);
        }

Matias Quaranta Matias Quaranta · Accepted Answer · 2021-04-08T00:37:25

Your second screenshot is showing that you are passing a token that starts with +RID... which is not how the previous token starts (previous token starts with [{"token").

Could you be dropping the JSON wrapping attributes that are part of the token?

The second call should be passing exactly [{"token":"+RID:~UVURALkfIb4FAAAAAAAAAA==#RT:1#TRC:3#RTD:hCgamV5sp6dv/pVR3z0oBTMxMzIuMTQuNDFVMTY7MjY7NDIvOTk3MzIxMlsA#ISV:2#IEO:65567#QCF:1#FPC:AQEAAAAAAAAACAAAAAAAAAA=","range":{"min":"","max":"FF"}}]. Keep in mind that you are also sending it in the URL, so there might be character escaping there too.

Azure Cosmos Pagination: FeedResponse.ContinuationToken not working in the next request

1 Answers