Function write_json 

pub fn write_json<T>(path: &Path, prefix: &str, value: &T) -> Result<()>
where
    T: Serialize + ?Sized,

Replaces path with value as pretty-printed JSON and one trailing newline, atomically and durably.

The staging file lands beside path under prefix; see create_staging_file for what a prefix may hold. path is left as it was unless the whole value serialized and reached disk.

Errors

• std::io::ErrorKind::InvalidInput if prefix holds / or \.
• std::io::Error carrying a serde_json::Error if value would not serialize, or reporting a failed stage, write, fsync or rename.