unbox
(Package: jsonlite) :
Unbox a vector or data frame
This function marks an atomic vector or data frame as a singleton, i.e. a set with exactly 1 element. Thereby, the value will not turn into an array when encoded into JSON. This can only be done for atomic vectors of length 1, or data frames with exactly 1 row. To automatically unbox all vectors of length 1 within an object, use the auto_unbox argument in toJSON.
These functions are used to convert between JSON data and R objects. The toJSON and fromJSON functions use a class based mapping, which follows conventions outlined in this paper: http://arxiv.org/abs/1403.2805 (also available as vignette).
The rbind.pages function is used to combine a list of data frames into a single data frame. This is often needed when working with a JSON API that limits the amount of data per request. If we need more data than what fits in a single request, we need to perform multiple requests that each retrieve a fragment of data, not unlike pages in a book. In practice this is often implemented using a page parameter in the API. The rbind.pages function can be used to combine these pages back into a single dataset.
In a nested data frame, one or more of the columns consist of another data frame. These structures frequently appear when parsing JSON data from the web. We can flatten such data frames into a regular 2 dimensional tabular structure.
The serializeJSON and unserializeJSON functions convert between R objects to JSON data. Instead of using a class based mapping like toJSON and fromJSON, the serialize functions base the encoding schema on the storage type, and capture all data and attributes from any object. Thereby the object can be restored almost perfectly from its JSON representation, but the resulting JSON output is very verbose. Apart from environments, all standard storage types are supported.
The stream_in and stream_out functions implement line-by-line processing of JSON data over a connection, such as a socket, url, file or pipe. JSON streaming requires the ndjson format, which slightly differs from fromJSON and toJSON, see details.
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