How to fix the concurrent update issue in ElasticSearch with Node.js development?

if we try to update the information from two different source with ElasticSearch.


we may encounter a concurrent issue. ElasticSearch has mechanish to prevent the concurrent update.

here is the sample code to get information from bundle and book information for response.

app.put('/api/bundle/:id/book/:pgid', async(req, res)=>{

        const bundleUrl =`${url}/${req.params.id}`;

        const bookUrl=`http://${es.host}:${es.port}/${es.books_index}/book/${req.params.pgid}`;

        try{

            const [bundleRes, bookRes]=await Promise.all([

                rp({url:bundleUrl, json:true}),

                rp({url:bookUrl, json:true})

            ]);

            console.log(bundleRes);

            const {_source: bundle, _version: version}=bundleRes;

            const {_source: book}=bookRes;

            console.log("if_seq_no:",if_seq_no);

            console.log("if_primary_term", if_primary_term);

            const idx=bundle.books.findIndex(book=>book.id===req.params.pgid);

            if(idx === -1){

                bundle.books.push({

                    id: req.params.pgid,

                    title: book.title

                });

            }

            const esResBody=await rp.put({

                url:bundleUrl,

                qs:{

  version: version, 

                    version_type: 'external',

                },

                body:bundle,

                json:true

            });

            res.status(200).json(esResBody);

        }catch(esResErr){

            res.status(esResErr.status ||502).json(esResErr.error);

        }

    })

initially i try to use the version number to resolve the concurrent issue. the error is thrown immediately after the request is made.

{
    "error": {
        "root_cause": [
            {
                "type": "action_request_validation_exception",
                "reason": "Validation Failed: 1: internal versioning can not be used for optimistic concurrency control. Please use `if_seq_no` and `if_primary_term` instead;"
            }
        ],
        "type": "action_request_validation_exception",
        "reason": "Validation Failed: 1: internal versioning can not be used for optimistic concurrency control. Please use `if_seq_no` and `if_primary_term` instead;"
    },
    "status": 400
}


based on the suggestion from the error message. i need to make couple of change, in order to fix the issue.

first we need to load the _seq_no and _primary_term from bundle response body.

 const {_source: bundle, _version: version,  
 _seq_no: if_seq_no, 
 _primary_term: 
 if_primary_term }=bundleRes;

 const {_source: book}=bookRes;

second, add if_seq_no and if_primary_term to the query string array 

const esResBody=await rp.put({

                url:bundleUrl,

                qs:{

                    if_seq_no: if_seq_no,

                    if_primary_term: if_primary_term

                },

                body:bundle,

                json:true

            });

Now the concurrent issue is gone. the title update is done,

 danhuideng@DESKTOP-EE785O3:/mnt/c/node/b4$ curl -s localhost:60702/api/bundle/$BUNDLE_ID |jq '._source'
{
  "name": "far",
  "books": [
    {
      "id": "pg132",
      "title": "The Art of War"
    }
  ]
}