4.4. 416 Range Not Satisfiable4.4. 416 Range Not Satisfiabl

4.4. 416 Range Not Satisfiable

返回416的时机

没有overlap
满足特定条件被rejected

For byte ranges, failing to overlap(TODO)

   For byte ranges, failing to overlap the current extent means that the
   first-byte-pos of all of the byte-range-spec values were greater than
   the current length of the selected representation..

要想满足“failing to overlap”，只需要所有的byte-range-spec满足：

first-byte-pos > current length - 1

但是上述节选中却说的是满足:

first-byte-pos > current length

SHOULD

When this status
   code is generated in response to a byte-range request, the sender
   SHOULD generate a Content-Range header field specifying the current
   length of the selected representation (Section 4.2)

Note

 Note: Because servers are free to ignore Range, many
      implementations will simply respond with the entire selected
      representation in a 200 (OK) response.  That is partly because
      most clients are prepared to receive a 200 (OK) to complete the
      task (albeit less efficiently) and partly because clients might
      not stop making an invalid partial request until they have
      received a complete representation.  Thus, clients cannot depend
      on receiving a 416 (Range Not Satisfiable) response even when it
      is most appropriate.