如何用正则提取WordPress wp-config数据库信息并通过Ansible自动化更新虚拟主机

问题描述 #

各位技术同仁：
我花费5小时调试正则表达式仍未解决问题，特此求助。需要一个正则表达式提取WordPress的数据库信息，用于Ansible剧本中。

目标格式示例：

/** The host of the database for WordPress */
define( 'DB_HOST', 'database_host_here' );

我尝试过ChatGPT等AI工具生成的多个正则表达式，均因转义问题失败。以下是当前使用的Ansible剧本：

---
- name: Update wp-config.php with new template
  hosts: localhost

  vars_prompt:
    - name: username
      prompt: "Enter the username"
      private: false

  vars:
    wp_config_filename: "wp-config.php"
    enable_debug: false
    multi_site: false
    search_paths:
      - "/home/{{ username }}/public_html/public"

  tasks:
    - name: Find wp-config.php files
      ansible.builtin.find:
        paths: "{{ search_paths }}"
        patterns: "{{ wp_config_filename }}"
      register: wp_config_files

    - name: Fail if no wp-config.php files found
      ansible.builtin.fail:
        msg: "No wp-config.php files found in the provided paths."
      when: wp_config_files.matched == 0

    - name: Debug wp-config.php files
      ansible.builtin.debug:
        var: wp_config_files

    - name: Read existing wp-config.php for database credentials
      ansible.builtin.slurp:
        src: "{{ item.path }}"
      loop: "{{ wp_config_files.files }}"
      loop_control:
        loop_var: item
      register: wp_config_content
      when: wp_config_files.matched > 0

    - name: Decode base64 encoded wp-config.php content
      ansible.builtin.set_fact:
        wp_config_decoded: "{{ wp_config_content.results | map(attribute='content') | map('b64decode') | list }}"

    - name: Debug decoded wp-config.php content
      ansible.builtin.debug:
        var: wp_config_decoded

    - name: Set database credentials from existing wp-config.php
      ansible.builtin.set_fact:
        db_host: "{{ item | regex_search('define\\(\\s*[\'\\\"]DB_HOST[\'\\\"]\\s*,\\s*[\'\\\"]([^\'\\\"]+)[\'\\\"]') | default('localhost') }}"
        db_name: "{{ item | regex_search('define\\(\\s*[\'\\\"]DB_NAME[\'\\\"]\\s*,\\s*[\'\\\"]([^\'\\\"]+)[\'\\\"]') | default('wordpress') }}"
        db_user: "{{ item | regex_search('define\\(\\s*[\'\\\"]DB_USER[\'\\\"]\\s*,\\s*[\'\\\"]([^\'\\\"]+)[\'\\\"]') | default('root') }}"
        db_password: "{{ item | regex_search('define\\(\\s*[\'\\\"]DB_PASSWORD[\'\\\"]\\s*,\\s*[\'\\\"]([^\'\\\"]+)[\'\\\"]') | default('password') }}"
      loop: "{{ wp_config_decoded }}"
      loop_control:
        loop_var: item

    - name: Debug extracted database credentials
      ansible.builtin.debug:
        msg: >
          DB Name: {{ db_name }},
          DB User: {{ db_user }},
          DB Password: {{ db_password }},
          DB Host: {{ db_host }}

    - name: Create a new wp-config.php from template
      ansible.builtin.template:
        src: "wp-config.php.j2"
        dest: "{{ item.path }}"
        mode: "0644"
      loop: "{{ wp_config_files.files }}"
      when: wp_config_files.matched > 0

我的应用场景是在虚拟主机环境下管理多个WordPress站点，需要自动化检测数据库信息、更新模板并部署到正确路径。最初使用的正则表达式：

define\(\s*[\'"]DB_HOST[\'"]\s*,\s*[\'"]([^\'"]+)[\'"]\)

该正则在Ansible中执行失败。

更新：解决方案 #

感谢@WiktorStribiżew的帮助，已找到适用于Ansible的regex_search正则表达式：

regex_search('define\\s*\\(\\s*[\\x22\\x27]DB_HOST[\\x22\\x27]\\s*,\\s*[\\x22\\x27]([^\\x22\\x27]+)[\\x22\\x27]\\s*\\)', '\\1') | first

更新2：完整参考剧本 #

基于@U880D的回复，以下是完整的Ansible剧本供有相同需求的用户参考：

---
- name: Update wp-config.php with new template
  hosts: all
  become: true

  tasks:
    - name: Find all user directories under /home
      ansible.builtin.find:
        paths: "{{ search_path }}"
        file_type: directory
      register: user_dirs

    - name: Find all wp-config.php files in user directories
      ansible.builtin.find:
        paths: "{{ item.path }}/public_html"
        patterns: "wp-config.php"
      register: wp_config_files
      loop: "{{ user_dirs.files }}"

    - name: Fail if no wp-config.php files found
      ansible.builtin.fail:
        msg: "No wp-config.php files found in the provided paths."
      when: wp_config_files.matched == 0

    - name: Debug wp-config.php files
      ansible.builtin.debug:
        var: wp_config_files

    - name: Read existing wp-config.php for database credentials
      ansible.builtin.slurp:
        src: "{{ item.path }}"
      loop: "{{ wp_config_files.files }}"
      register: wp_config_content
      when: wp_config_files.matched > 0

    - name: Debug wp-config.php content
      ansible.builtin.debug:
        var: wp_config_content.results

    - name: Set database credentials from existing wp-config.php
      ansible.builtin.set_fact:
        db_host: >-
          {{ item.content | b64decode | regex_search('DB_HOST(.+)', '\\1') | regex_search('([A-Za-z])+') }}
        db_name: >-
          {{ item.content | b64decode | regex_search('DB_NAME(.+)', '\\1') | regex_search('([A-Za-z])+') }}
        db_user: >-
          {{ item.content | b64decode | regex_search('DB_USER(.+)', '\\1') | regex_search('([A-Za-z])+') }}
        db_password: >-
          {{ item.content | b64decode | regex_search('DB_PASSWORD(.+)', '\\1') | regex_search('([A-Za-z])+') }}
      loop: "{{ wp_config_content.results }}"
      loop_control:
        loop_var: item
      when: item.content is defined

    - name: Debug extracted database credentials
      ansible.builtin.debug:
        msg: >-
          DB Name: {{ db_name }},
          DB User: {{ db_user }},
          DB Password: {{ db_password }},
          DB Host: {{ db_host }}

    - name: Create a new wp-config.php from template
      ansible.builtin.template:
        src: "wp-config.php.j2"
        dest: "{{ item.path }}"
        mode: "0644"
      loop: "{{ wp_config_files.files }}"
      when: wp_config_files.matched > 0

内容的提问来源于stack exchange，提问作者fariscode