PHP : Fix Call to undefined function curl_init() error

Problem:

Some PHP libraries or packages depend on your server having curl program installed. Missing curl or the PHP to curl bridge can cause problem during development or deployment phase.

For example, you are developing your PHP program and you encounter the following error message during test phase:

 An uncaught Exception was encountered

 Type: Error

 Message: Call to undefined function curl_init()

How to fix this problem?

Solution:

The server is missing php-curl or php7-curl package. Install them by

For Cent OS:

sudo yum install php5-curl or sudo yum install php7-curl

and

sudo yum install curl

For Ubuntu:

sudo apt-get install php5-curl or sudo apt-get install php7-curl

and

sudo apt-get install curl