Why is there no output in jinja2 Loop? - jinja2

Question

i try to loop over a dic in my jinja template. But i always get no output.
dic={"SERVICE1" : "tess","SERVICE2" : "test"}
with open(Path(Path.cwd()/"test.jinja")) as f:
template = Template(f.read()).render(data_nebula_docker)
print(template)
My template looks like this:
{% for item in dic %}
{{item}}
{% endfor %}
Normal Variablse are working fine. Does i have some basic misunderstanding?
Thx for your help!

Answer 1

There are a couple of problems with your code. I'm going to assume the indentation issue in your with statement is just a copy-and-paste error, and that your code actually looks like:
with open(Path(Path.cwd()/"test.jinja")) as f:
template = Template(f.read()).render(data_nebula_docker)
print(template)
In your template you're referencing a variable dic, but you aren't passing this to the render method. You want:
from jinja2 import Template
from pathlib import Path
dic = {"SERVICE1": "tess", "SERVICE2": "test"}
with open(Path(Path.cwd() / "test.jinja")) as f:
template = Template(f.read()).render(dic=dic)
print(template)
Which produces:
SERVICE1
SERVICE2
You'll note that this only prints out the keys in your dictionary. When you iterate over a dictionary (in Jinja or Python), you get a list of keys. If you want (key, value) tuples instead, use the .items() method:
{% for item in dic.items() %}
{{item}}
{% endfor %}
Which produces:
('SERVICE1', 'tess')
('SERVICE2', 'test')
Separately, your use of pathlib.Path is a little convoluted; you can write instead:
with (Path.cwd()/"test.jinja").open() as f:
In the above:
It's not necessary to wrap the result of Path() / "string" in a call to Path() (because it's already a Path)
A Path object has an open method, so we can call .open() on the Path that results from Path.cwd()/"test.jinja".
Although in this case, your pathlib based code isn't much of a win over:
with open("test.jinja") as f: