Set a curl output to a variable in a Dockerfile

Question

basically i'm doing a curl and grepping some stuff. But, i want set the output of this curl to a variable, to then use it on another curl. e.g:

curl -u asd:asd http://zzz:123/aa/aa.aaa?cmd=ls | grep -B1 -E '<bbb>[4-7]\d{8,}' | grep yyy | tail -n 1 | sed -n -e 's/.*<xxx>\(.*\)<\/xxx>.*/\1/p')

but then I want set the output to a var and use it:

RUN aaa=$(previous curl) && curl -u asd:asd http://$aaa.com

tried with ${aaa}, with "$aaa", etc... didn't work. any solutions?

UPDATE: something wrong is happening in previous curl 'cause doesn't return the value. probably for not doing the curl

Does this answer your question? https://stackoverflow.com/q/4651437/1563297 — Sergio Santiago, Oct 24 '22 at 23:53
"*... didn't work. ..."* - what does that mean? Is the variable empty? Has it an unexpected value? — Turing85, Oct 24 '22 at 23:53
@SergioSantiago I don’t think so, I need to run it inside my dockerfile — asd123, Oct 25 '22 at 00:22
Are you trying to run these in the same `RUN` command, or in separate lines? Assuming you fill in "previous curl" correctly, the last `RUN` line you show seems like it should be correct. — David Maze, Oct 25 '22 at 10:30
@DavidMaze same RUN command. seems like it doesn't run the curl, 'cause in the commandline works perfectly — asd123, Oct 25 '22 at 10:44

score 0 · Answer 1 · edited Jan 31 '23 at 10:23

0

I fear you will not be able to acheive this, because from my understanding RUN statement is to execute a command. To store value you'll have use SET.

For me the following workaround helped

RUN export aaa=$(curl -u asd:asd http://$aaa.com);echo aaa;

You can add the downsteam commands that will use the variable aaa towards right of the semicolon

edited Jan 31 '23 at 10:23

helvete

answered Jan 25 '23 at 01:45

user3769597

1 Answers1