Running curl with os.execute

Developer's Corner Scene Scripting
#1

I have a curl command that I am trying to run in a scene. I’ve SSHed into the Vera and run the Curl command successfully, but whenever I try to move it into a scene calling curl via the os.execute I receive the error “failed attempt to call a nil valuee[0m <0x74174520>”

os.execute(“curl -k https://api.twilio.com/2010-04-01/Accounts/censored/Calls.json -u ‘censored:censored’ --data-urlencode ‘From=5617553581’ --data-urlencode ‘To=3057557687’ --data-urlencode ‘Url=http://twimlets.com/message?Message[0]=This%20is%20Premier&’”)

#2

[quote=“Floridagator, post:1, topic:198462”]I have a curl command that I am trying to run in a scene. I’ve SSHed into the Vera and run the Curl command successfully, but whenever I try to move it into a scene calling curl via the os.execute I receive the error “failed attempt to call a nil valuee[0m <0x74174520>”

os.execute(“curl -k https://api.twilio.com/2010-04-01/Accounts/censored/Calls.json -u ‘censored:censored’ --data-urlencode ‘From=5617553581’ --data-urlencode ‘To=3057557687’ --data-urlencode ‘Url=http://twimlets.com/message?Message[0]=This%20is%20Premier&’”)[/quote]

I had the same problem and found the answer by testing on my own linux box.

use a single quote for the whole command and the URL in double quotes.

Example:
os.execute(‘curl -X GET “http://192.168.254.38/api/v1/commands/?cmd=playplaylist&name=panic”’)

There’s a single quote before the curl command and another one at the end of the statement after the double quote.

1 Like
#3

Great answer! Thanks for sharing.

For completeness, Lua also has a further string quoting mechanism, which allows you to embed both single and double quotes in a string.

S = [[ both 'single' and "double" quotes in a string ]]

There’s even an extension of this which allows [[ or ]] to be in a quoted string, but I’ll leave that as an exercise for the reader!

#4

The brackets are good to know. I just got a Vera Plus, so now time to learn Lua… :o

#5

Thanks for the reply! Wish there was an easier way to test LUA code on the Vera.

#6

At least two easy ways:

[ul][li]Rex Beckett’s excellent LuaTest http://forum.micasaverde.com/index.php/topic,24018.0.html [/li]
[li]amg0’s fantastic AltUI plugin http://forum.micasaverde.com/index.php/board,78.0.html which does so much more as well[/li][/ul]

Both the above allow you to use the print command to see output, which Vera’s native Test Lua window does not.

#7

For people in the future who come here looking for a way to execute ‘curl’ in their Vera with JSON… I was able to figure it out when I was trying to get Slack webhooks to work. This worked for me. Notice how the quotes need to be escaped in just the right way.

os.execute(‘curl -X POST -k -H 'Content-type: application/json' -d '{"text":"hello world"}' https://hooks.slack.com/services/AAAAAA/BBBBB/CCCCCC’)

#8

For people in the future who come here looking for a way to execute ‘curl’ in their Vera with JSON… I was able to figure it out when I was trying to get Slack webhooks to work. This worked for me. Notice how the quotes need to be escaped in just the right way.

os.execute(‘curl -X POST -k -H 'Content-type: application/json' -d '{"text":"hello world"}' https://hooks.slack.com/services/AAAAAA/BBBBB/CCCCCC’)

#9

I try to run

os.execute(‘curl -s --data-binary ‘{“jsonrpc”:“2.0”,“id”:“1”,“method”:“Player.Open”,“params”:{“item”:{“file”:“special://profile/playlists/music/f.m3u”}}}’ -H ‘Content-type: application/json’ http://192.168.1.5:8080/jsonrpc’)

but it does not work in any way?
Can anybody help me to correct the code?

#10

Click the first link below.

Also, please don’t cross-post the same question to multiple topics. It isn’t necessary and makes the threads harder to follow for future users trying to get the same solution.

1 Like
#11

Thanks a lot.

Sure, I will not do that again.