Mask email ID in MongoDB

In MongoDB, you can mask email IDs using the aggregation framework along with string manipulation operators. Below is an example of how to implement this:

db.collection.aggregate([

  {

    $addFields: {

      masked_email: {

        $concat: [

          { $substr: ["$email", 0, { $indexOfCP: ["$email", "@"] }] },

          "XXXXX",

          { $substr: ["$email", { $indexOfCP: ["$email", "@"] }, -1] }

        ]

      }

    }

  }

])

This pipeline adds a new field masked_email to each document in the collection, which contains the masked email ID with 'XXXXX' replacing the local part.

Example:

Let's say you have a document in the collection with the email ID 'example@example.com':

db.collection.insertOne({email: 'example@example.com'})

Applying the aggregation pipeline:

db.collection.aggregate([

  {

    $addFields: {

      masked_email: {

        $concat: [

          { $substr: ["$email", 0, { $indexOfCP: ["$email", "@"] }] },

          "XXXXX",

          { $substr: ["$email", { $indexOfCP: ["$email", "@"] }, -1] }

        ]

      }

    }

  }

])

The result would be:

{

  "email": "example@example.com",

  "masked_email": "exampleXXXXX@example.com"

}

Here are few FAQs:-

1. Why should email IDs be masked in a database?

   - Email IDs are personal identifiers that, when exposed, can lead to privacy concerns or unauthorized access. Masking them helps protect user privacy and enhances data security.

2. Can the original email ID be retrieved from the masked version?

   - Ideally, the masking process should be irreversible to maintain data security. Therefore, the original email ID should not be easily retrievable from the masked version.

3. How can I ensure that masked email IDs remain usable for certain operations?

   - By retaining some part of the original email ID, such as the domain name, you can maintain the usability of the data for operations like communication or identification, while still protecting sensitive information.

4. Are there any legal requirements for masking email IDs?

   - Depending on the jurisdiction and the nature of the data being handled, there may be legal requirements or industry standards mandating the protection of personally identifiable information (PII), which includes email IDs.

5. Can I customize the masking format for email IDs?

   - Yes, you can customize the masking format according to your requirements. The provided aggregation pipeline can be modified to accommodate different masking formats or variations in email ID structures.