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Why is my '_id' field empty when retrieving Article objects using mgo?

DDD

Nov 06, 2024 pm 06:27 PM

Why is my

Unable to Retrieve "_id" Value in Go with Mgo

Your code attempts to retrieve a list of Article objects from a database using the mgo library. However, upon printing the result, you discover that the "_id" field is consistently empty. This can be attributed to a subtle error in your struct definition.

In your Article struct, the line:

Id bson.ObjectId `json:"id" bson:"_id,omitempty"`

incorrectly uses a tab character instead of a space between the json and bson tags. This syntax error can cause mgo to misinterpret the field definition.

To resolve this issue, simply replace the tab character with a space, so the line becomes:

Id bson.ObjectId `json:"id" bson:"_id,omitempty"`

With this correction, mgo will now correctly parse the struct definition and retrieve the "_id" field values properly.

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