centos7安装python3

1.准备安装工具

yum groupinstall "Development tools"
 
yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-develtk-devel gdbm-devel db4-devel libpcap-devel xz-devel

2.下载python3源码

wget https://www.python.org/ftp/python/3.7.5/Python-3.7.5.tgz

3.解压

tar  xf Python-3.7.5.tgz ./

4.进入下载目录

cd Python-3.7.5

5.编译

./configure --prefix=/usr/local/python3
make&& make install

6.创建软链接

ln -s /usr/local/python3/bin/python3 /usr/bin/python3
ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3

7. 问题处理

解决pythonssl问题
因openssl 1.0.1存在安全问题，python3自3.7版本后要求依赖openssl 1.0.2以上或libressl；错误提示如下：

Python requires an OpenSSL 1.0.2 or 1.1 compatible libssl with X509_VERIFY_P

python3.7以上建议使用libressl代替openssl，故需通过源码编译安装libressl

下载源码包

wget https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-3.0.2.tar.gz

解压

tar -zxvf libressl-3.0.2.tar.gz

配置安装路径

mkdir /usr/local/libressl
cd libressl-3.0.2

./configure --prefix=/usr/local/libressl

安装

make & make install

创建软连接代替openssl

mv /usr/bin/openssl /usr/bin/openssl.bak

mv /usr/include/openssl /usr/include/openssl.bak

ln -s /usr/local/libressl/bin/openssl /usr/bin/openssl
ln -s /usr/local/libressl/include/openssl /usr/include/openssl
echo /usr/local/libressl/lib >> /etc/ld.so.conf.d/libressl-3.0.2.conf
ldconfig -v

验证是否安装完成

openssl version

export LDFLAGS="-L/usr/local/libressl/lib"
export CPPFLAGS="-I/usr/local/libressl/include"
export PKG_CONFIG_PATH="/usr/local/libressl/lib/pkgconfig"

配置编译安装python

./configure --prefix=/usr/local/python3
make
make install