使用mgo将数据插入MongoDB

Question

I'm trying to insert some data in MongoDB using Go.

Here is the data struct:

type Entry struct {
    Id          string `json:"id",bson:"_id,omitempty"`
    ResourceId  int    `json:"resource_id,bson:"resource_id"`
    Word        string `json:"word",bson:"word"`
    Meaning     string `json:"meaning",bson:"meaning"`
    Example     string `json:"example",bson:"example"`
}

This is my insert function:

func insertEntry(db *mgo.Session, entry *Entry) error {
    c := db.DB(*mongoDB).C("entries")
    count, err := c.Find(bson.M{"resourceid": entry.ResourceId}).Limit(1).Count()
    if err != nil {
        return err
    }
    if count > 0 {
        return fmt.Errorf("resource %s already exists", entry.ResourceId)
    }
    return c.Insert(entry)
}

And finally, this is how I call it:

entry := &Entry{
    ResourceId:  resourceId,
    Word:        word,
    Meaning:     meaning,
    Example:     example,
}
err = insertEntry(db, entry)
if err != nil {
    log.Println("Could not save the entry to MongoDB:", err)
}

The trouble is, I was expecting my bson tags to magically work, but they don't. Instead of data being saved as:

{ "_id" : ObjectId("53700d9cd83e146623e6bfb4"), "resource_id" : 7660708, "word" : "Foo" ...}

It gets saved as:

{ "_id" : ObjectId("53700d9cd83e146623e6bfb4"), "id" : "", "resourceid" : 7660708, "word" : "Foo"...}

How can I fix this?

Answer 1

Change entry to:

type Entry struct {
    Id          string `json:"id" bson:"_id,omitempty"`
    ResourceId  int    `json:"resource_id" bson:"resource_id"`
    Word        string `json:"word" bson:"word"`
    Meaning     string `json:"meaning" bson:"meaning"`
    Example     string `json:"example" bson:"example"`
}

The syntax for Struct Tags does not use commas between tags. I believe this should fix it.