如何在Ansible set_fact中使用fact？

Posted 2021-04-17

我试图避免重复包含文件中的值。我尝试在附带的文件中添加顶级name，vars和tasks：

---
- name: Install Terraform
  vars:
    terraform_base_url: "https://releases.hashicorp.com/terraform/{{ terraform_version }}"
    terraform_package_file: "terraform_{{ terraform_version }}_linux_amd64.zip"
    terraform_package_url: "{{ terraform_base_url }}/{{ terraform_package_file }}"
    terraform_checksum_url: "{{ terraform_base_url }}/terraform_{{ terraform_version }}_SHA256SUMS"
    terraform_package_path: "/tmp/{{ terraform_package_file }}"

  tasks:
  - name: Install unzip package
  …

这导致“在任务中未检测到任何操作”错误。我也尝试删除tasks标题并将所有任务放在顶层，但得到了相同的结果。所以我设置了这样的变量（terraform_version在剧本中定义）：

- name: Set Terraform variables
  set_fact:
    terraform_base_url: "https://releases.hashicorp.com/terraform/{{ terraform_version }}"
    terraform_package_file: "terraform_{{ terraform_version }}_linux_amd64.zip"
    terraform_package_url: "{{ terraform_base_url }}/{{ terraform_package_file }}"
    terraform_checksum_url: "{{ terraform_base_url }}/terraform_{{ terraform_version }}_SHA256SUMS"
    terraform_package_path: "/tmp/{{ terraform_package_file }}"

ansible-lint没有抱怨这个，但由于某种原因，第二个变量中的terraform_base_url引用中断：

The task includes an option with an undefined variable. The error was: 'terraform_base_url' is undefined

The error appears to have been in '/vagrant/provisioning/ansible/install-terraform.yml': line 2, column 3, but may
be elsewhere in the file depending on the exact syntax problem.
The offending line appears to be:
---
- name: Set Terraform variables
  ^ here

如果可以为包含的文件设置vars（即文件中所有任务可用的变量而不重复它们），那就更好了。

答案

它看起来必须分成两部分才能工作：

- name: Set Terraform variables 1
  set_fact:
    terraform_base_url: "https://releases.hashicorp.com/terraform/{{ terraform_version }}"
    terraform_package_file: "terraform_{{ terraform_version }}_linux_amd64.zip"

- name: Set Terraform variables 2
  set_fact:
    terraform_package_url: "{{ terraform_base_url }}/{{ terraform_package_file }}"
    terraform_checksum_url: "{{ terraform_base_url }}/terraform_{{ terraform_version }}_SHA256SUMS"
    terraform_package_path: "/tmp/{{ terraform_package_file }}"

另一答案

如果以后不需要中间变量，可以使用var语句：

- name: Set Terraform variables
  set_fact:
    terraform_package_url: "{{ terraform_base_url }}/{{ terraform_package_file }}"
    terraform_checksum_url: "{{ terraform_base_url }}/terraform_{{ terraform_version }}_SHA256SUMS"
    terraform_package_path: "/tmp/{{ terraform_package_file }}"
  vars:
    terraform_base_url: "https://releases.hashicorp.com/terraform/{{ terraform_version }}"
    terraform_package_file: "terraform_{{ terraform_version }}_linux_amd64.zip"

此外，你很有可能在这里不需要set_fact。在任何级别使用vars部分（游戏，任务），或者将它们放在rolevarsmain.yaml中作为角色。