Trying to prevent duplicate entries not working-CodePudding

I am fetching data from an API (array of objects) and I want to then check in the database if any of the records exist, using the url as the basis for duplicates. When it comes to inserting the new records, I get this monogoDB error:

MongoBulkWriteError: E11000 duplicate key error collection: news.news index: sourceUrl_1 dup key: { sourceUrl: "https://example.com/article-abc123" }

  try {
    const covidDbArticles = await News.find({ category: "Coronavirus" });
    const filterCovidDuplicates = covidData.data.news.filter(
      (covidApiSource) =>
        !covidDbArticles.some(
          (covidDatabaseSource) =>
            covidApiSource.link === covidDatabaseSource.sourceUrl
        )
    );
    if (filterCovidDuplicates.length) {
      try {
        await News.insertMany(covidNewsObj);
      } catch (err) {
        console.log("Error inserting covid data: "   err);
      }
    }
  } catch (err) {
    console.log("saving data failed: "   err);
  }

CodePudding user response：

Filter does not change the original array. So when you use covidNewsObj, you are sending up all the duplicates.

So you would need to set the result of the filter back to the property.

covidData.data.news = covidData.data.news.filter(...);