# Loops and Conditionals — Ansible: Automate Servers with Playbooks

Source: https://www.geekswithgeeks.com/en/ansible/flow-loops-when

> Repeat a task over a list with loop and skip it with when.

## loop and when

`loop:` runs a task once per item of a list, exposing the current value as `item`. `when:` runs a task only if a condition is true; otherwise the result is **skipping**. The condition is a Jinja2 expression written without braces, such as `env == "production"` or `ansible_os_family == "Debian"`. Combine conditions with `and`, `or` and `not`.

## Decide, repeat, react

Conditions, loops, handlers and tags give playbooks logic without turning them into scripts.

![Three tools: when, loop, notify.](assets/figures/ansible/section-4-map.svg) — Figure 4.1 — when, loop and notify.

## Loop and skip, run

I ran `vars.yml` (shown in the previous section) with its default `env: staging`: the loop prints three installs, and the production-only task is skipped.

```bash
ansible-playbook -i inventory.ini vars.yml
```

Output:

```
ok: [web1] => (item=git) => {
    "msg": "install git"
ok: [web1] => (item=curl) => {
    "msg": "install curl"
ok: [web1] => (item=nginx) => {
    "msg": "install nginx"
skipping: [web1]
```

## Do not over-script

If a playbook is full of nested conditions, consider splitting it into roles or using variables to express the difference. Complex logic is hard to test and review.

**Quiz:** What result do you see when a `when:` condition is false?

- [ ] changed
- [x] skipping
- [ ] failed
- [ ] unreachable

*Answer:* skipping. A task whose condition is false is skipped for that host.