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# CodeBuild 在显式代理服务器中运行
要 AWS CodeBuild 在显式代理服务器上运行，必须将代理服务器配置为允许或拒绝进出外部站点的流量，然后配置`HTTP_PROXY`和`HTTPS_PROXY`环境变量。
**Topics**
+ [将 Squid 配置为显式代理服务器](#use-proxy-server-explicit-squid-configure)
+ [创建 CodeBuild 项目](#use-proxy-server-explicit-create-acb-project)
+ [显式代理服务器示例 `squid.conf` 文件](#use-proxy-server-explicit-sample-squid-conf)
## 将 Squid 配置为显式代理服务器
要将 Squid 代理服务器配置为显式，您必须对其 `/etc/squid/squid.conf` 文件进行以下修改：
+ 删除以下默认访问控制列表（ACL）规则。
```
acl localnet src 10.0.0.0/8
acl localnet src 172.16.0.0/12
acl localnet src 192.168.0.0/16
acl localnet src fc00::/7
acl localnet src fe80::/10
```
在您删除的默认 ACL 规则的位置添加以下内容。第一行允许来自您的 VPC 的请求。接下来的两行授予您的代理服务器访问可能 URLs 使用的目标的权限 AWS CodeBuild。编辑最后一行的正则表达式以指定 S3 存储桶或 AWS 区域中的 CodeCommit 存储库。例如：
+ 如果您的源是 Amazon S3，请使用命令 **acl download\$1src dstdom\$1regex .\$1s3\$1.us-west-1\$1.amazonaws\$1.com** 来授权访问 `us-west-1` 区域中的 S3 存储桶。
+ 如果您的来源是 AWS CodeCommit，请使用将 AWS 区域`git-codecommit..amazonaws.com`添加到允许列表中。
```
acl localnet src 10.1.0.0/16 #Only allow requests from within the VPC
acl allowed_sites dstdomain .github.com #Allows to download source from GitHub
acl allowed_sites dstdomain .bitbucket.com #Allows to download source from Bitbucket
acl download_src dstdom_regex .*\.amazonaws\.com #Allows to download source from Amazon S3 or CodeCommit
```
+ 将 `http_access allow localnet` 替换为以下项：
```
http_access allow localnet allowed_sites
http_access allow localnet download_src
```
+ 如果您希望构建上传日志和构件，请执行以下任一操作：
1. 在 `http_access deny all` 语句之前，插入以下语句。它们允许 CodeBuild 访问 CloudWatch 和 Amazon S3。需要 CloudWatch 访问权限 CodeBuild 才能创建 CloudWatch 日志。上传构件和 Amazon S3 缓存需要访问 Amazon S3。
+
```
https_port 3130 cert=/etc/squid/ssl/squid.pem ssl-bump intercept
acl SSL_port port 443
http_access allow SSL_port
acl allowed_https_sites ssl::server_name .amazonaws.com
acl step1 at_step SslBump1
acl step2 at_step SslBump2
acl step3 at_step SslBump3
ssl_bump peek step1 all
ssl_bump peek step2 allowed_https_sites
ssl_bump splice step3 allowed_https_sites
ssl_bump terminate step2 all
```
+ 保存 `squid.conf` 后，运行以下命令：
```
sudo iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-port 3130
sudo service squid restart
```
1. 将 `proxy` 添加到您的 buildspec 文件。有关更多信息，请参阅 [buildspec 语法](build-spec-ref.md#build-spec-ref-syntax)。
```
version: 0.2
proxy:
upload-artifacts: yes
logs: yes
phases:
build:
commands:
- command
```
**注意**
如果您收到 RequestError 超时错误，请参阅[RequestError CodeBuild 在代理服务器上运行时出现超时错误](troubleshooting.md#code-request-timeout-error)。
有关更多信息，请参阅本主题后面的[显式代理服务器示例 `squid.conf` 文件](#use-proxy-server-explicit-sample-squid-conf)。
## 创建 CodeBuild 项目
要 AWS CodeBuild 使用显式代理服务器运行，请使用您为代理服务器创建的 EC2 实例的私有 IP 地址`HTTP_PROXY`和项目级别的端口 3128 来设置其和`HTTPS_PROXY`环境变量。私有 IP 地址看起来类似于 `http://your-ec2-private-ip-address:3128`。有关更多信息，请参阅[在 中创建构建项目AWS CodeBuild](create-project.md)和[在中更改构建项目设置 AWS CodeBuild](change-project.md)。
使用以下命令查看 Squid 代理服务器访问日志：
```
sudo tail -f /var/log/squid/access.log
```
## 显式代理服务器示例 `squid.conf` 文件
以下是为显式代理服务器配置的 `squid.conf` 文件的示例。
```
acl localnet src 10.0.0.0/16 #Only allow requests from within the VPC
# add all URLS to be whitelisted for download source and commands to be run in build environment
acl allowed_sites dstdomain .github.com #Allows to download source from github
acl allowed_sites dstdomain .bitbucket.com #Allows to download source from bitbucket
acl allowed_sites dstdomain ppa.launchpad.net #Allows to run apt-get in build environment
acl download_src dstdom_regex .*\.amazonaws\.com #Allows to download source from S3 or CodeCommit
acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT
#
# Recommended minimum Access Permission configuration:
#
# Deny requests to certain unsafe ports
http_access deny !Safe_ports
# Deny CONNECT to other than secure SSL ports
http_access deny CONNECT !SSL_ports
# Only allow cachemgr access from localhost
http_access allow localhost manager
http_access deny manager
# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on "localhost" is a local user
#http_access deny to_localhost
#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#
# Example rule allowing access from your local networks.
# Adapt localnet in the ACL section to list your (internal) IP networks
# from where browsing should be allowed
http_access allow localnet allowed_sites
http_access allow localnet download_src
http_access allow localhost
# Add this for CodeBuild to access CWL end point, caching and upload artifacts S3 bucket end point
https_port 3130 cert=/etc/squid/ssl/squid.pem ssl-bump intercept
acl SSL_port port 443
http_access allow SSL_port
acl allowed_https_sites ssl::server_name .amazonaws.com
acl step1 at_step SslBump1
acl step2 at_step SslBump2
acl step3 at_step SslBump3
ssl_bump peek step1 all
ssl_bump peek step2 allowed_https_sites
ssl_bump splice step3 allowed_https_sites
ssl_bump terminate step2 all
# And finally deny all other access to this proxy
http_access deny all
# Squid normally listens to port 3128
http_port 3128
# Uncomment and adjust the following to add a disk cache directory.
#cache_dir ufs /var/spool/squid 100 16 256
# Leave coredumps in the first cache dir
coredump_dir /var/spool/squid
#
# Add any of your own refresh_pattern entries above these.
#
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
refresh_pattern . 0 20% 4320
```