Nextcloud与OpenProject集成时的SSL证书问题求助

希望有遇到类似问题的用户能分享解决方案。我尝试将Nextcloud与OpenProject进行集成，但始终无法成功。

架构示意图：

我已按照官方文档配置（或尝试配置）这两个服务，使用Nginx作为代理服务（原文Node-Package-Manager应为笔误）。

配置详情 #

OpenProject配置 #

• 使用非自签名的通配符证书
• 自定义代理配置：

proxy_set_header X-Forwarded-Host $host:$server_port;
proxy_set_header X-Forwarded-Proto https;

• 自带Apache服务器配置（基于外部SSL终止相关文档）：

Include /etc/openproject/addons/apache2/includes/server/*.conf
IncludeOptional /etc/openproject/addons/apache2/custom/server/*.conf

<VirtualHost *:80>
  ServerName openproject.example.net
  DocumentRoot /opt/openproject/public

  ProxyRequests off

  Include /etc/openproject/addons/apache2/includes/vhost/*.conf
  IncludeOptional /etc/openproject/addons/apache2/custom/vhost/*.conf

  # Can't use Location block since it would overshadow all the other proxypass directives on CentOS
  ProxyPass / http://127.0.0.1:6000/ retry=0
  ProxyPassReverse / http://127.0.0.1:6000/
</VirtualHost>

Nextcloud配置 #

• Nginx自定义配置：

client_body_buffer_size 512k;
proxy_read_timeout 86400s;
client_max_body_size 0;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
add_header Front-End-Https on;

• config.php修改（基于反向代理配置文档）：

'overwrite.cli.url' => 'https://nextcloud.example.net',
  'trusted_proxies'   => ['192.168.1.44'],
  'overwritehost'     => 'nextcloud.example.net',
  'overwriteprotocol' => 'https',
  'overwritewebroot'  => '/',
  'overwritecondaddr' => '^192\.168\.1\.44$',

测试结果 #

按照集成排障文档的测试方法执行以下命令：

curl --location --request GET 'https://nextcloud.example.net/index.php/apps/integration_openproject/check-config' --header 'Authorization: foo'

返回错误：

curl: (60) SSL certificate problem: unable to get local issuer certificate
More details here: https://curl.se/docs/sslcerts.html

curl failed to verify the legitimacy of the server and therefore could not
establish a secure connection to it. To learn more about this situation and
how to fix it, please visit the web page mentioned above.

我已经尝试了所有官方文档中的配置方法，但仍无法建立连接。不知道遗漏了什么配置项，也不清楚还有哪些排查方向，恳请大家提供帮助。

内容的提问来源于stack exchange，提问作者MichaelT