Working with GitLab is awesome this tool has a lot of features and I really like it, one of the advantages is its big community and documentation also there are tons of ideas to improve this tool.
Recently working in a pipeline I realized that it could be great to have a variable like a list in order to have something like a while or a for-each sadly I couldn’t see something similar to use.
For that reason, I made this simple workaround, pass a variable like a string then create a document like a txt and finally apply a xagrs command.
Challenge.
Create a standard CI/CD for python projects those projects use different packages from many sources for that reason it is necessary to repeat many times the curl instruction.
Sample of .gitlab-ci with multiple lines to reapet the curl
- before_script:
- #download and package content
- – curl sS -o paquete1.tar http://www.regner.com.mx/instalando-jenkins-en-una-vm-centos/
- – curl sS -o paquete2.tar https://stackoverflow.com/questions/8445445/
- – curl sS -o paquete3.tar https://stackoverflow.com/questions/
Solution.
Create a variable to set those different url’s and having a simple “while”
- create our variable.
- create a txt file with a valid format to be sorted
- apply the curl instruction in each line
#variable in one single line \n is used to have new rows
NECESARYPACKAGES: -sS -o paquete1.tar http://www.regner.com.mx/instalando-jenkins-en-una-vm-centos/ \n -sS -o paquete2.tar https://stackoverflow.com/questions/8445445/ \n -sS -o https://stackoverflow.com/questions/Having a variable we could set multiple rows or instructions separated by \n
Now we are going to pass the content of that variable as a txt file. with a simple echo
- echo -e "${NECESARYPACKAGES}" >> packsgen.txtthe result of this is a packsgen.txt with this content:
sS -o paquete1.tar http://www.regner.com.mx/instalando-jenkins-en-una-vm-centos
sS -o paquete2.tar https://stackoverflow.com/questions/8445445
sS -o paquete3.tar https://stackoverflow.com/questions/
Time to apply our curl sentence.
- xargs -n4 curl < packsgen.txt
-n4 is used because our lines are composed each 4 components sS -o tarfile URL if you don’t have this way to separate each line you could get an error because xargs + curl will take the file content as a single row.
Try by your self:
In a console or terminal window.
echo -e "-sS -o paquete1.tar http://www.regner.com.mx/instalando-jenkins-en-una-vm-centos/ \n-sS -o paquete2.tar https://stackoverflow.com/questions/8445445/ \n-sS -o paquete3.tar https://stackoverflow.com/questions/" >> packsgen.txt
xargs -n4 curl < packsgen.txtThis has to produce these files: 3 packages.tar and 1 txt file.
In the end, you could parametrize the content in one variable to reuse code and your Gitlab-ci will appear nice.
