The /camli/<blobref> endpoint returns a blob the server knows about.

A request with the GET verb will return 200 and the blob contents if
present, 404 if not. A request with the HEAD verb will return 200 and
the blob meta data (i.e., content-length), or 404 if the blob is not
present.

The response must include an explicit Content-Length, even with HTTP/1.1.
(The one piece of metadata a blobserver keeps on a blob is its length,
 which is used in both enumerate-blobs bodies and responses to blob GETs.)

Get the blob:

GET /camli/sha1-126249fd8c18cbb5312a5705746a2af87fba9538 HTTP/1.1
Host: example.com

Response:

HTTP/1.1 200 OK
Content-Type: application/octet-stream
Content-Length: <the blob length in bytes>

<the blob contents>


Existence check:

HEAD /camli/sha1-126249fd8c18cbb5312a5705746a2af87fba9538 HTTP/1.1
Host: example.com

Response:

HTTP/1.1 200 OK
Content-Type: application/octet-stream
Content-Length: <the blob length in bytes>


Does not exist:

GET /camli/sha1-126249fd8c18cbb5312a5705746a2af87fba9538 HTTP/1.1
Host: example.com

Response:

HTTP/1.1 404 OK