api_client.php

<?php

class ApiClient
	{
	/**
	* @return Project[]
	*/
	public function getProjects(): array
		{
		$projects = [];
		$response = $this->client->get('https://some-awesome.api/projects');
		$data = json_decode($response->getBody()->getContents(), true);
		
		// Some associative array property guessing...
		if (!empty($data['Result']))
			{
			foreach ($data['Result'] as $projectData)
				{
				if ($projectData['SaleStatus'] === 'InActiveSale')
					{
					$projects[] = Project::fromApiResponse($projectData);
					}
				}
			}
		
		return $projects;
		}
	
	public function addNewProject(Project $project)
		{
		$this->client->post('https://some-awesome.api/projects', ['body' => $project->toApiRequestPayload() ]);
		}
 	}

project.php

<?php

class Project
	{
	public static function fromApiResponse(array $data): self
		{
		$project = new Project();
		
		// Manual mapping of arrays to object properties..
		$project->setInternalId( (string) $data['Id']);
		$project->setTitle($data['Name']);
		$project->setQuality((int)$data['Quality']);
		// ...
		
		return $project;
		}
	
	public function toApiRequestPayload(): array
		{
		$data = [];
		
		// Manual mapping of object properties to arrays..
		$data['Id'] = (int) $this->getInternalId();
		$data['Name'] = $this->getTitle();
		$data['Quality'] = (float) $this->getQuality();
		// ...
		
		return $data;
		}
 	}