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Creating API Endpoints for Specific Data

In this tutorial, you will create multiple APIFocused endpoints that return differentthe typessmallest ofuseful data.result for a particular user need. This tutorial adds filtered and summary endpoints using PDO and fictional records.

This

Endpoint approachfor isone commonly used in modern web applications.

Why Create Multiple Endpoints?severity

Your current API returns all records:

api_events.php

This works, but many applications need smaller, more focused datasets.

For example:

api_events.php
api_critical_events.php
api_statistics.php

Each endpoint has a specific purpose.

Create a Critical Events API

Create:

api_critical_events.api/events-by-severity.php

Add::

<?php
$conndeclare(strict_types=1);

=require new__DIR__ mysqli(. "localhost",'/../includes/database.php';

"root",header('Content-Type: "",application/json; "project_db"
charset=utf-8');
header('Cache-Control: "Content-Type: application/json"
no-store');

$queryallowed = "['low', 'medium', 'high', 'critical'];
$severity = strtolower(trim($_GET['severity'] ?? ''));

if (!in_array($severity, $allowed, true)) {
    http_response_code(400);
    echo json_encode([
        'ok' => false,
        'error' => 'Choose low, medium, high or critical.'
    ]);
    exit;
}

$statement = $pdo->prepare(
    'SELECT
        *event_id,
        event_timestamp,
        device_id,
        room,
        event_type,
        severity
     FROM security_events
     WHERE severity = 'critical':severity
     "ORDER BY event_timestamp DESC
     LIMIT 100'
);

$resultstatement->execute(['severity' => $conn->query($query)severity]);
$events = []$statement->fetchAll();

while (
    $row =
    $result->fetch_assoc()
) {

    $events[] = $row;

}

echo json_encode([
    'ok' => true,
    'filter' => ['severity' => $events,severity],
    JSON_PRETTY_PRINT'count' => count($events),
    'events' => $events
]);

?>

Test theit Endpointwith

Open:a fictional category:

http://localhost/api-demo/api_critical_events.phpproject/api/events-by-severity.php?severity=high

YouThe shouldallow-list onlyrejects seeunexpected criticalvalues events.and the prepared statement keeps the supplied value separate from the SQL.

Endpoint

Screenshotfor Placeholder

summary

Insert screenshot showing critical event results.

Create a Statistics APItotals

Create:

Create 
api_statistics.api/event-summary.php

Add::

<?php
$conndeclare(strict_types=1);

=require new__DIR__ mysqli(. "localhost",'/../includes/database.php';

"root",header('Content-Type: "",application/json; "project_db"
charset=utf-8');
header('Cache-Control: "Content-Type: application/json"
no-store');

$statistics = [

    "total_events" => 0,
    "critical_events" => 0,
    "high_events" => 0

];

$resultstatement = $conn-pdo->query(
    "'SELECT COUNT(*) AS total
         FROM security_events"
    );

$statistics["total_events"] =
    $result->fetch_assoc()["total"];

$result =
    $conn->query(
        "SELECTseverity, COUNT(*) AS total
     FROM security_events
     WHEREGROUP severity='critical'"BY severity
     ORDER BY severity'
);

$statistics["critical_events"rows = $statement->fetchAll();

$summary = [];

foreach ($rows as $row) {
    $summary[] = [
        'severity' => $result-row['severity'],
        'total' =>fetch_assoc()["total" (int) $row['total']
    ];
$result =
    $conn->query(
        "SELECT COUNT(*) AS total
         FROM security_events
         WHERE severity='high'"
    );

$statistics["high_events"] =
    $result->fetch_assoc()["total"];}

echo json_encode([
    'ok' => true,
    'summary' => $statistics,summary
JSON_PRETTY_PRINT
]);

?>

Test the Statistics Endpoint

Open:

http://localhost/api-demo/api_statistics.php

Example:

{
    "total_events": 3,
    "critical_events": 1,
    "high_events": 1
}

Read the Statistics API with JavaScript

Create:

dashboard.html

Add:

<!DOCTYPE html>
<html>
<head>
    <title>Dashboard</title>
</head>
<body>

<h1>Security Dashboard</h1>

<div id="output"></div>

<script>

fetch("api_statistics.php")
    .then(response => response.json())
    .then(data => {

        document.getElementById(
            "output"
        ).innerHTML = `

            <p>
                Total Events:
                ${data.total_events}
            </p>

            <p>
                Critical Events:
                ${data.critical_events}
            </p>

            <p>
                High Events:
                ${data.high_events}
            </p>

        `;

    });

</script>

</body>
</html>

Common Endpoint Examples

Many real systems use endpoints such as:

/api/users
/api/products
/api/orders
/api/messages
/api/statistics

EachThis endpoint returns processed information rather than every event record. It can support an accessible table or chart.

Choose endpoints from user needs

Useful endpoints might answer:

    Which fictional events require urgent review? How many events occurred in each category? Which events belong to a selected device? How has the event count changed over time?

    Avoid creating many endpoints that expose the same unnecessary fields.

    Check

      Invalid filters return HTTP 400 and a clear JSON error. User-supplied values are validated and passed through prepared statements. Totals are cast to numbers before encoding. Responses contain only the data required byfields. theNo application.personal
      information

      Summary

      or

      Youcredentials noware have:

      exposed. 
      api_events.phpAll
      demonstration

      Returnsrecords allare events.

      fictional. 
      api_critical_events.php

      Returns only critical events.

      api_statistics.php

      Returns dashboard statistics.

      This approach keeps APIs organised and makes applications easier to maintain.

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