mac系统中使用mamp+composer.phar安装yii2

• 首先电脑安装mamp集成软件
• 把MAMP下的php复制到Mac环境变量目录，这步很关键，例如：

# /Applications/MAMP/bin/php/php7.2.22/bin/php  是mamp中某个php版本的具体位置
# /usr/local/bin/php72   是路径，其中php72是自己定义的名字

cp /Applications/MAMP/bin/php/php7.2.22/bin/php  /usr/local/bin/php72

• 从https://getcomposer.org/download/ 下载composer.phar，放到项目根目录。
• 测试，输入php72 composer.phar -v之后可以看的composer版本信息
• 将composer.phar的镜像地址改为阿里云的地址，如下所示

php72 composer.phar config -g repo.packagist composer https://mirrors.aliyun.com/composer/

• 输入php72 composer.phar config -l -g查看是否成功。
• 使用如下命令安装yii2-mongo拓展，如下所示：

php72 composer.phar require --prefer-dist yiisoft/yii2-mongodb

• 执行完上一个命令后得到如下所示：

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - yiisoft/yii2-mongodb[2.1.0, ..., 2.1.9] require ext-mongodb >=1.0.0 -> it is missing from your system. Install or enable PHP's mongodb extension.
    - Root composer.json requires yiisoft/yii2-mongodb ^2.1 -> satisfiable by yiisoft/yii2-mongodb[2.1.0, ..., 2.1.9].

To enable extensions, verify that they are enabled in your .ini files:
    - /Applications/MAMP/bin/php/php7.2.22/conf/php.ini
You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

Installation failed, reverting ./composer.json and ./composer.lock to their original content.

• 提示需要在php.ini中添加mongodb extension,实际上mamp中的extension=mongodb.so是开启的。但是/Applications/MAMP/bin/php/php7.2.22/conf路径下是没有php.ini文件的。
• 可以打开mamp软件，点击php，查看相应php版本的ini配置文件，软件中打开时会自动弹出。将php.ini中的内容复制，并在/Applications/MAMP/bin/php/php7.2.22/conf中创建一个php.ini文件，并将复制的内容粘贴进去。
• 此时再执行命令：

php72 composer.phar require --prefer-dist yiisoft/yii2-mongodb

# 命令执行后有如下提示：

Using version ^2.1 for yiisoft/yii2-mongodb
./composer.json has been updated
Running composer update yiisoft/yii2-mongodb
Loading composer repositories with package information
Updating dependencies
Lock file operations: 1 install, 0 updates, 3 removals
  - Removing bshaffer/oauth2-server-php (v1.11.1)
  - Removing filsh/yii2-oauth2-server (v2.1.1)
  - Removing windhoney/yii2-rest-rbac (1.0.9)
  - Locking yiisoft/yii2-mongodb (2.1.9)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 1 install, 0 updates, 3 removals
  - Downloading yiisoft/yii2-mongodb (2.1.9)
  - Removing windhoney/yii2-rest-rbac (1.0.9)
  - Removing filsh/yii2-oauth2-server (v2.1.1)
  - Removing bshaffer/oauth2-server-php (v1.11.1)
  - Installing yiisoft/yii2-mongodb (2.1.9): Extracting archive
Package phpunit/php-token-stream is abandoned, you should avoid using it. No replacement was suggested.
Generating autoload files
28 packages you are using are looking for funding.
Use the `composer fund` command to find out more!

• 再到项目的/vendor/yiisoft/中可以看的此时yii2-mongodb已经安装进来了。

如果哪里看不明白或者觉得我写的不清楚，可以私信我。我是费了很大的功夫才解决的，愿意分享出来。