composer 安装依赖时缺少gd库
报错- mpdf/mpdf v8.0.4 requires ext-gd * -> it is missing from your system. Install or enable PHP’s gd extension

docker下 php安装gd，zip扩展

gd库安装

apt-get install --allow-downgrades -y  zlib1g=1:1.2.8.dfsg-5 zlib1g-dev libz-dev libfreetype6-dev libjpeg62-turbo-dev libpng-dev \
    && docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ \
    && docker-php-ext-install -j$(nproc) gd

zip库

apt-get update && apt-get install -y \
        zlib1g-dev \
        libzip-dev \
        unzip
   docker-php-ext-install zip