First swipe at using the CAP API to retreive a the full text of a case.

capapi.php

<?php
/**
 * Working with Harvard's CAP API
 *
 */
$authorization = "Token your-API-key-here";
$cite = "309 F.2d 912";
$full_case = "true";
$body_format = "html";

$params = array(
	'cite' => $cite,
	'full_case' => $full_case,
	'body_format' => $body_format,
);

$query = http_build_query($params);

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, "https://api.case.law/v1/cases/?$query");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
	'Authorization: '.$authorization,
	)
);

$result = curl_exec($ch);
curl_close($ch);
//echo "<pre>".$result."</pre><hr>";
 
$capresult = (json_decode($result,true));
//print("<pre>".print_r($capresult,true)."</pre>");
echo $capresult['results'][0]['casebody']['data'];
?>

To get a n API key you'll need to create an account on case.law and then visit https://case.law/user/details.