Why Are Only Capitalized Struct Fields Updated in CouchDB Using go-couchdb?

Capitalization Impacts Data Storage in CouchDB structs

When utilizing the "github.com/mikebell-org/go-couchdb" library to access CouchDB, a peculiar issue arises: only struct fields with capitalized initial letters are updated in database inserts.

Example:

type Person struct {
    name string
    Age  int
}

Upon inserting a Person instance into the database:

joe := Person{
    name: "mike",
    Age:  190,
}

Only the Age field is added to the database. Other lowercase fields, like name, are omitted.

The Reason Behind the Behavior:

This behavior stems from the Go language specification, which dictates that fields with lowercase initial letters are not exported. As a result, the JSON serialization package (e.g., json) only includes these fields if explicitly instructed to do so.

Overcoming the Issue:

To incorporate lowercase fields into the database, utilize JSON tags:

type Person struct {
    name string `json:"name"`
    Age  int    `json:"Age"`
}

By specifying the json tag, the lowercase name field is explicitly exposed for JSON serialization, allowing it to be persisted in the database. Refer to the documentation for further details on JSON tags.

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