Im wondering how to best guarantee that a field is unique and isn't saved to the datastore if it isn't. Also that it should be required. I am using this field as stringID and need it to be unique. I know that I can simply try to get an entity by this field and see if it exists and build a logic around it. But is there a simpler way like declaring in your struct that the field should be unique and/or required? Like the mockup below.
type Car struct {
Regnr string "required" "unique"
}
Thanks!
From the Datastore API:
By default, for struct pointers, all properties are potentially indexed, and the property name is the same as the field name (and hence must start with an upper case letter). Fields may have a
datastore:"name,options"tag. The tag name is the property name, which must be one or more valid Go identifiers joined by ".", but may start with a lower case letter. An empty tag name means to just use the field name. A "-" tag name means that the datastore will ignore that field. If options is "noindex" then the field will not be indexed. If the options is "" then the comma may be omitted. There are no other recognized options.
Not possible to set those type of tags with Datastore.