Is a single string value considered valid JSON? [duplicate]

Answer 1

There's a change of heart on this between RFC4627 and RFC7159:

RFC4627:

A JSON text is a serialized object or array.

  JSON-text = object / array

RFC7159:

A JSON text is a serialized value. Note that certain previous
specifications of JSON constrained a JSON text to be an object or an
array. Implementations that generate only objects or arrays where a
JSON text is called for will be interoperable in the sense that all
implementations will accept these as conforming JSON texts.

  JSON-text = ws value ws

No philosophical or practical justification is provided for this change of heart. The earlier version probably makes more sense as it consistently dictates that both a singe list element and a single map element (a pair or tuple) be contained. The second version allows only a single list element to be uncontained.

Answer 2

I don't care if some validator accepts it. It's wrong. It's a question of good practice, Json format must be {"key": "value", .....}. If you consider that text Json, can work, but for the rest of programmer it's not a serious Json. If you use only that text, then you don't need Json.

Answer 3

As for new JSON RFC, json, containing only single value is pretty valid.

A JSON text is a serialized value. Note that certain previous specifications of JSON constrained a JSON text to be an object or an array.

Answer 4

According to the grammar exposed in http://www.json.org/ (which references the Standard ECMA-262 3rd Edition - December 1999 par.5.1.5 The JSON Grammar) it's wrong:

The initial element must be:

and then a value can be a string:

Answer 5

From RFC4627:

A JSON text is a serialized object or array.
    JSON-text = object / array

IE, the root element has to be an object or array, and can't be a string value by itself.