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paps33's avatar
paps33
Visitor
15 years ago

Question on using POST /launch/

I am trying to send the roku a POST /launch ECP command to launch a particular channel, but keep getting back a "HTTP/1.1 400 Bad Request" response. Say I wanted to launch the Netflix channel. Its my understanding that I simply plug the proper app id (as returned by query/apps) in to the launch command. For example, with Netflix (app id = 12) I send the command:

POST /launch/12 HTTP/1.1 (with the appropriate cr lf following)

For a basic launch of this channel there really aren't any parameters to also put in. Or are there? Am I missing something? I get similar failed responses when trying to launch, say, Vimeo or others.
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14 Replies

  • RokuChris's avatar
    RokuChris
    Roku Employee
    15 years ago
    Sounds like you are on the right track. The launch command does not require any parameters. I can successfully launch the Netflix channel using this command from a terminal and substituting the IP address of a Roku:

    curl -d "" "http://xxx.xxx.xxx.xxx:8060/launch/12"
  • TheEndless's avatar
    TheEndless
    Channel Surfer
    15 years ago
    That syntax works fine for me. Are you specifying the HOST header with the appropriate 8060 port?
  • paps33's avatar
    paps33
    Visitor
    15 years ago
    Thanks for the responses.

    I'm doing a send to the same address/port (port being 8060) that I use for, say, a GET /query/apps or a POST /keypress (which work). The exact data I send is as in my first post, namely (for netflix):

    "POST /launch/12 HTTP/1.1" (without the quotes and with two appended carriage return line feeds)

    TheEndless, are you saying I need to literally include (append) a "Host: xxx.xxx.xxx.xxx:8060" on to the post data sent?
  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    15 years ago
    Yes, the HTTP protocol requires a Host header. You probably also need a Content-Length:0 header.

    --Mark
  • paps33's avatar
    paps33
    Visitor
    15 years ago
    Ah, so I assume that this is because HTTP 1.1 is being used as opposed to 1.0? But why then is it that if I do a POST for something like the KEYPRESS I have no problem withno header supplied?

    Note: In the SDK example program to launch an app they provide no host header, but they use HTTP 1.0.
  • RokuKevin's avatar
    RokuKevin
    Visitor
    15 years ago
    Here's an example to launch netflix.... insert your ipaddress in the line below:

    echo -e "POST /launch/12 HTTP/1.1\r\n\r\n" | ncat 192.168.1.120 8060

    --Kevin
  • paps33's avatar
    paps33
    Visitor
    15 years ago
    RokuKevin,

    That may work with ncat, but when (just) the line POST /launch/12 HTTP/1.1\r\n\r\n is sent programatically I get the "400 Bad Request" mentioned initially. I have not try it yet, but it may well be as TheEndless has suggested. With HTTP 1.1 (vs 1.0) the addtional header(s) are needed, at least the HOST: . I will try it and see. If it works then it will be puzzling why something like the POST keypress works without the header. That might mean there is something improper in the ROKU firmware.

    I'll post what I find...
  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    15 years ago
    Sorry for the confusion -- it appears that no headers are necessary with either the keypress or launch commands.
    The string you are sending should work fine. Make sure you don't have any extraneous characters queued up in the socket (like from a previous command) before you send your command. That could cause the 400 error you're seeing.

    --Mark
  • paps33's avatar
    paps33
    Visitor
    15 years ago
    Well for what it is worth...

    When I had been trying to issue a POST launch (HTTP 1.1, not 1.0) without any headers I had no success. I confirmed (I swear) the content of the command text was fine. However, when I now add an additional Host: header (ie. Host: xxxx.xxxx.xxxx.xxxx:8060) the command(s) work and the channels launch. Makes sense, since the HTTP 1.1 spec does say the header (at least the host) is required.

    My thanks to TheEndless for putting me on the right track!
  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    15 years ago
    Hm, well it works for me without headers. I do "telnet 192.168.1.xxx 8060" and then enter "POST /launch/12 HTTP/1.1" followed by two newlines, and I get a 200 OK response. But there's certainly no harm in adhering to the spec by sending the Host header.

    --Mark