Hello!
On Mon, Jun 4, 2012 at 10:01 AM, Sammy R. [email protected]
wrote:
I am trying to stream video it can be mp4, flv anything using nginx.
The video streams in the form of 1024 size will be available from the
backend non-http server.
I think this can be done trivially via ngx_lua module while still
achieving good performance. Here is a small example that demonstrates
how to meet your requirements with a little Lua:
location /api {
content_by_lua '
local sock, err = ngx.socket.tcp()
if not sock then
ngx.log(ngx.ERR, "failed to get socket: ", err)
ngx.exit(500)
end
sock:settimeout(1000) -- 1 sec
local ok, err = sock:connect("some.backend.host", 12345)
if not ok then
ngx.log(ngx.ERR, "failed to connect to upstream: ", err)
ngx.exit(502)
end
local bytes, err = sock:send("some query")
if not bytes then
ngx.log(ngx.ERR, "failed to send query: ", err)
ngx.exit(502)
end
while true do
local data, err, partial = sock:receive(1024)
if not data then
if err == "closed" then
if partial then
ngx.print(partial)
ngx.eof()
ngx.exit(ngx.OK)
end
else
ngx.log(ngx.ERR, "error reading data: ", err)
ngx.exit(502)
end
else
ngx.print(data)
ngx.flush(true)
end
end
';
}
See the documentation for details:
http://wiki.nginx.org/HttpLuaModule
For achieveing this I followed the ngx_http_drizzle source.
I wrote an upstream handler and followed most of the source code from
ngx_http_drizzle.
As the author of ngx_drizzle, I suggest you start from trying out
ngx_lua. Customizing ngx_drizzle for your needs requires a lot of
work. The C approach should only be attempted when Lua is indeed too
slow for your purpose, which is not very likely for many applications
though.
Also, please note that ngx_drizzle does not support strict
non-buffered data output. So, for downstream connections that are slow
to write, data will still accumulate in RAM without control. On the
other hand, the ngx_lua sample given above does not suffer from this
issue.
I have few questions or to be more precise I did not understood how the
output from drizzle is being streamed to the client.
- In ngx_http_drizzle_output.c the function ngx_http_drizzle_submit_mem is
the place where it is setting the output filter, Is it also sending the
response i.e the stream to the client at this point, or it is some other
function?
Nope. Sending output buffers to the output filter chain is done by the
ngx_http_drizzle_output_bufs function.
- What I need to do to send my video contents to the client, I followed the
drizzle example but setting output and sending stream to the client, how I
can achieve this. I have 1024B avaialble at one point and I want to send
this to the client till the backend server has no stream to send and the
client should be able to play the content.
Basically, you can call the ngx_http_output_filter function, just as
other nginx upstream modules.
- Is it possible to send the video stream to the client with the browser.
I do not quite follow this question.
Best regards,
-agentzh
