[Slim4] Add array support to Data Mocker

[ybelenko]

PR checklist

• Read the contribution guidelines.
• If contributing template-only or documentation-only changes which will change sample output, build the project before.
• Run the shell script(s) under ./bin/ (or Windows batch scripts under.\bin\windows) to update Petstore samples related to your fix. This is important, as CI jobs will verify all generator outputs of your HEAD commit, and these must match the expectations made by your contribution. You only need to run ./bin/{LANG}-petstore.sh, ./bin/openapi3/{LANG}-petstore.sh if updating the code or mustache templates for a language ({LANG}) (e.g. php, ruby, python, etc).
• File the PR against the correct branch: master, 4.3.x, 5.0.x. Default: master.
• Copy the technical committee to review the pull request if your PR is targeting a particular programming language.

mockArray method added to interface and implemented class. Mocker creates smallest arrays(single item when possible) to avoid huge JSON responses.

Related to #3545

How to test

1. Checkout into feature branch

$ git checkout -b ybelenko-slim_data_mocker_array master
$ git pull https://github.com/ybelenko/openapi-generator.git slim_data_mocker_array

2. Generate new Slim4 samples and go to just created build

$ mvn clean package
$ bin/php-slim4-server-petstore.sh
$ cd samples/server/petstore/php-slim4

3. Start Composer installation and run unit tests

$ composer install
$ composer test
$ composer phpcs

cc @jebentier, @dkarlovi, @mandrean, @jfastnacht, @ackintosh, @renepardon

[ybelenko]

I've made a small example of what do we have right now:

<?php
require __DIR__ . '/vendor/autoload.php';

use OpenAPIServer\Mock\OpenApiDataMocker as Mocker;
$mocker = new Mocker();
$data = [
    'Integer from 1 to 100' => $mocker->mockInteger(null, 1, 100),
    'Float from -3 to 3' =>  $mocker->mockNumber(null, -3, 3),
    'String 10 chars' => $mocker->mockString(null, 10, 10),
    'Boolean' =>  $mocker->mockBoolean(),
    'Array of strings' => $mocker->mockArray(
        [
            'type' => 'string',
            'maxLength' => 20,
        ]
    ),
];
echo json_encode($data, JSON_PRETTY_PRINT);

output:

{
    "Integer from 1 to 100": 89,
    "Float from -3 to 3": -1.1508,
    "String 10 chars": "Lorem ipsu",
    "Boolean": false,
    "Array of strings": [
        "Lorem ipsum dol"
    ]
}

[wing328]

Start Composer installation and run unit tests

What about adding these steps to the CI tests in a separate PR?

I only saw tests for php-slim but not php-slim4 in the CI.

[ybelenko]

Start Composer installation and run unit tests

What about adding these steps to the CI tests in a separate PR?

I only saw tests for php-slim but not php-slim4 in the CI.

Where I should add them? I didn't know that CI runs any tests from samples.

[wing328]

https://github.com/OpenAPITools/openapi-generator/blob/master/samples/server/petstore/php-slim/pom.xml is a good starting point. You will need to add a similar file for slim4 (you will need to use a different artifact ID)

then add another line similar to https://github.com/OpenAPITools/openapi-generator/blob/master/pom.xml#L1050 in pom.xml