状況

Docker Image : php:7.4.6-fpm-alpine3.11

ログ

# composer require linecorp/line-bot-sdk
Using version ^4.4 for linecorp/line-bot-sdk
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - linecorp/line-bot-sdk 4.4.1 requires ext-sockets * -> the requested PHP extension sockets is missing from your system.
    - linecorp/line-bot-sdk 4.4.0 requires ext-sockets * -> the requested PHP extension sockets is missing from your system.
    - Installation request for linecorp/line-bot-sdk ^4.4 -> satisfiable by linecorp/line-bot-sdk[4.4.0, 4.4.1].

  To enable extensions, verify that they are enabled in your .ini files:
    - 
    - /usr/local/etc/php/conf.d/docker-php-ext-pdo_mysql.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-sodium.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

the requested PHP extension sockets is missing from your system.

socketsが無いよというお話でした。

対処

Dockerfile内でsocketsをインストールするだけ。

~略~
RUN docker-php-ext-install sockets
~略~

結果

無事、インストール完了

 # composer require linecorp/line-bot-sdk
Using version ^4.4 for linecorp/line-bot-sdk
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 1 install, 0 updates, 0 removals
  - Installing linecorp/line-bot-sdk (4.4.1): Downloading (100%)         
linecorp/line-bot-sdk suggests installing apigen/apigen (Install with roave/better-reflection:dev-master to generate docs)
linecorp/line-bot-sdk suggests installing roave/better-reflection (Required by apigen/apigen:dev-master)
Package jakub-onderka/php-console-color is abandoned, you should avoid using it. Use php-parallel-lint/php-console-color instead.
Package jakub-onderka/php-console-highlighter is abandoned, you should avoid using it. Use php-parallel-lint/php-console-highlighter instead.
Writing lock file
Generating optimized autoload files
> Illuminate\Foundation\ComposerScripts::postAutoloadDump
> @php artisan package:discover --ansi
Discovered Package: facade/ignition
Discovered Package: fideloper/proxy
Discovered Package: laravel/tinker
Discovered Package: nesbot/carbon
Discovered Package: nunomaduro/collision
Package manifest generated successfully.
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