REST API with cURL

Official doc.

In Postman, we can click on "Code snippet" icon (on the right side) to show the curl command (and other commands too).

General

Note that, -X = --request.

1curl -X [method] [options] [URL]

cURL in PHP

💡

We need to install the PHP extension “php-curl” to use it. Check Official Documentation to learn more

1// create & initialize a curl session
2$curl = curl_init();
3
4/**
5* Some code
6**/ 
7
8// close curl resource to free up system resources
9// (deletes the variable made by curl_init)
10curl_close($curl);

1# GET
2curl_setopt($curl, CURLOPT_URL, 'https://api.github.com/events');
3# request header
4curl_setopt($curl, CURLOPT_HTTPHEADER, array(
5    'Content-Type: application/json',
6		'User-Agent: cURL'
7 ));
8$r = curl_exec($curl);

1# POST
2curl_setopt($curl, CURLOPT_URL, 'https://httpbin.org/post');
3curl_setopt($curl, CURLOPT_POST, 1);
4# request header
5curl_setopt($curl, CURLOPT_HTTPHEADER, array(
6    'Content-Type: application/json',
7 ));
8curl_setopt($curl, CURLOPT_POSTFIELDS, '{"key": "value"}');
9$r = curl_exec($curl);

Response

1// Raw text
2$r
3
4# JSON
5json_decode($r, true);

Status code ???

1$statusCode = curl_getinfo($curl, CURLINFO_HTTP_CODE); // $statusCode = 200

Some examples

GET

1curl -X GET '<http://abc:3000/xyz/enpoint?paramOne=1&paramTwo=2>' \
2	--header 'clientEmail: [email protected]' \
3	--header 'privateKey: XXXX'
4	}'

POST

The JSON data must be in the form of '{with the "double quotes" inside}'. This "{single 'quote' inside}" will not work!

In case you wanna get a good form of data (with the quotes) from a variable (Python),

1curl -X POST '<http://abc:3000/xyz/enpoint?paramOne=1&paramTwo=2>' \
2	--header 'clientEmail: [email protected]' \
3	--header 'privateKey: LS0tLS1CRUdJTiBQUklWQVRFIEtFWS0tLS0tCk1JSUV2Z0lCQU' \
4	--header 'Content-Type: application/json' \
5	--data-raw '{
6		"dataMain": {
7			"keyOne": "valueOne",
8			"keyTwo": 2
9		}
10	}'

or,

1curl -X POST -H "Content-Type: application/json" \
2    -d '{"name": "linuxize", "email": "[email protected]"}' \
3    <https://example/contact>

Or with a JSON file,

1curl -X POST \
2  -H "Content-Type: application/json" \
3  --data @.folder/file.json \
4  <http://localhost:8080/ui/webapp/conf>

With a form

1<form method="POST" enctype='multipart/form-data' action="upload.cgi">
2  <input type=file name=upload>
3  <input type=submit name=press value="OK">
4</form>

1<!-- POST with file upload
2-F = --form
3-->
4curl -F upload=@/home/user/Pictures/wallpaper.jpg -F press=OK [URL]