the composer always return failed

[chiefysu]

Cloning into '/home/wwwroot/phpci/PHPCI/build/21_20e6a'...

dc61336420091713043c86477e3d5c174549a78e
Working copy created: /
RUNNING PLUGIN: composer
Composer could not find a composer.json file in /home/wwwroot/phpci/PHPCI/build/21_20e6a
To initialize a project, please create a composer.json file as described in the https://getcomposer.org/ "Getting Started" section

PLUGIN: FAILED
Exception: Plugin failed: composer
Removing Build.

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Expected behaviour

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Actual behaviour

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Environment info

Operating System: Debian 9 64bit
PHP Version: 7.1.7
MySQL Version: 5.6.3

I have set up the composer.json into repo

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