What is the difference between PUT, POST and PATCH?

Difference between PUT, POST, GET, DELETE and PATCH in HTTP Verbs:

The most commonly used HTTP verbs POST, GET, PUT, DELETE are similar to CRUD (Create, Read, Update and Delete) operations in database. We specify these HTTP verbs in the capital case. So, the below is the comparison between them.

Create - POST Read - GET Update - PUT Delete - DELETE

PATCH: Submits a partial modification to a resource. If you only need to update one field for the resource, you may want to use the PATCH method.

Note: Since POST, PUT, DELETE modifies the content, the tests with Fiddler for the below url just mimicks the updations. It doesn't delete or modify actually. We can just see the status codes to check whether insertions, updations, deletions occur.

URL: http://jsonplaceholder.typicode.com/posts/

GET:

GET is the simplest type of HTTP request method; the one that browsers use each time you click a link or type a URL into the address bar. It instructs the server to transmit the data identified by the URL to the client. Data should never be modified on the server side as a result of a GET request. In this sense, a GET request is read-only.

Checking with Fiddler or PostMan: We can use Fiddler for checking the response. Open Fiddler and select the Compose tab. Specify the verb and url as shown below and click Execute to check the response.

Verb: GET

url: http://jsonplaceholder.typicode.com/posts/

Response: You will get the response as:

"userId": 1,  "id": 1,  "title": "sunt aut...",  "body": "quia et suscipit..."

In the “happy” (or non-error) path, GET returns a representation in XML or JSON and an HTTP response code of 200 (OK). In an error case, it most often returns a 404 (NOT FOUND) or 400 (BAD REQUEST).

2) POST:

The POST verb is mostly utilized to create new resources. In particular, it's used to create subordinate resources. That is, subordinate to some other (e.g. parent) resource.

On successful creation, return HTTP status 201, returning a Location header with a link to the newly-created resource with the 201 HTTP status.

Checking with Fiddler or PostMan: We can use Fiddler for checking the response. Open Fiddler and select the Compose tab. Specify the verb and url as shown below and click Execute to check the response.

Verb: POST

url: http://jsonplaceholder.typicode.com/posts/

Request Body:

data: {
   title: 'foo',
   body: 'bar',
   userId: 1000,
   Id : 1000
}

Response: You would receive the response code as 201.

If we want to check the inserted record with Id = 1000 change the verb to Get and use the same url and click Execute.

As said earlier, the above url only allows reads (GET), we cannot read the updated data in real.

3) PUT:

PUT is most-often utilized for update capabilities, PUT-ing to a known resource URI with the request body containing the newly-updated representation of the original resource.

Checking with Fiddler or PostMan: We can use Fiddler for checking the response. Open Fiddler and select the Compose tab. Specify the verb and url as shown below and click Execute to check the response.

Verb: PUT

url: http://jsonplaceholder.typicode.com/posts/1

Request Body:

data: {
   title: 'foo',
   body: 'bar',
   userId: 1,
   Id : 1
}

Response: On successful update it returns status 200 (or 204 if not returning any content in the body) from a PUT.

4) DELETE:

DELETE is pretty easy to understand. It is used to delete a resource identified by a URI.

On successful deletion, return HTTP status 200 (OK) along with a response body, perhaps the representation of the deleted item (often demands too much bandwidth), or a wrapped response (see Return Values below). Either that or return HTTP status 204 (NO CONTENT) with no response body. In other words, a 204 status with no body, or the JSEND-style response and HTTP status 200 are the recommended responses.

Checking with Fiddler or PostMan: We can use Fiddler for checking the response. Open Fiddler and select the Compose tab. Specify the verb and url as shown below and click Execute to check the response.

Verb: DELETE

url: http://jsonplaceholder.typicode.com/posts/1

Response: On successful deletion it returns HTTP status 200 (OK) along with a response body.

Example between PUT and PATCH

PUT

If I had to change my first name then send PUT request for Update:

{ "first": "Nazmul", "last": "hasan" }

So, here in order to update the first name we need to send all the parameters of the data again.

PATCH:

Patch request says that we would only send the data that we need to modify without modifying or effecting other parts of the data. Ex: if we need to update only the first name, we pass only the first name.

Please refer the below links for more information:

https://jsonplaceholder.typicode.com/

https://github.com/typicode/jsonplaceholder#how-to

What is the main difference between PATCH and PUT request?

http://www.restapitutorial.com/lessons/httpmethods.html

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The below definition is from the real world example.

Example Overview For every client data, we are storing an identifier to find that client data and we will send back that identifier to the client for reference.

POST If the client sends data without any identifier, then we will store the data and assign/generate a new identifier. If the client again sends the same data without any identifier, then we will store the data and assign/generate a new identifier. Note: Duplication is allowed here. PUT If the client sends data with an identifier, then we will check whether that identifier exists. If the identifier exists, we will update the resource with the data, else we will create a resource with the data and assign/generate a new identifier. PATCH If the client sends data with an identifier, then we will check whether that identifier exists. If the identifier exists, we will update the resource with the data, else we will throw an exception.

Note: On the PUT method, we are not throwing an exception if an identifier is not found. But in the PATCH method, we are throwing an exception if the identifier is not found.

Do let me know if you have any queries on the above.

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Here is a simple description of all:

POST is always for creating a resource ( does not matter if it was duplicated )

PUT is for checking if resource exists then update, else create new resource

PATCH is always for updating a resource

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PUT = replace the ENTIRE RESOURCE with the new representation provided

PATCH = replace parts of the source resource with the values provided AND|OR other parts of the resource are updated that you havent provided (timestamps) AND|OR updating the resource effects other resources (relationships)

https://laracasts.com/discuss/channels/general-discussion/whats-the-differences-between-put-and-patch?page=1

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Simplest Explanation:

POST - Create NEW record

PUT - If the record exists, update else, create a new record

PATCH - update

GET - read

DELETE - delete

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Think of it this way...

POST - create

PUT - replace

PATCH - update

GET - read

DELETE - delete

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Request Types

create - POST

read - GET

create or update - PUT

delete - DELETE

update - PATCH

GET/PUT is idempotent PATCH can be sometimes idempotent

What is idempotent - It means if we fire the query multiple times it should not afftect the result of it.(same output.Suppose a cow is pregnant and if we breed it again then it cannot be pregnent multiple times)

get :-

simple get. Get the data from server and show it to user

{
id:1
name:parth
email:x@x.com
}

post :-

create new resource at Database. It means it adds new data. Its not idempotent.

put :-

Create new resource otherwise add to existing. Idempotent because it will update the same resource everytime and output will be the same. ex. - initial data

{
id:1
name:parth
email:x@x.com
}

perform put-localhost/1 put email:ppp@ppp.com

{
id:1
email:ppp@ppp.com
}

patch

so now came patch request PATCH can be sometimes idempotent

id:1
name:parth
email:x@x.com
}

patch name:w

{
id:1
name:w
email:x@x.com
}

HTTP  Method
GET     yes
POST    no
PUT     yes
PATCH   no*
OPTIONS yes
HEAD    yes
DELETE  yes

Resources : Idempotent -- What is Idempotency?

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Main Difference Between PUT and PATCH Requests:

Suppose we have a resource that holds the first name and last name of a person.

If we want to change the first name then we send a put request for Update

{ "first": "Michael", "last": "Angelo" }

Here, although we are only changing the first name, with PUT request we have to send both parameters first and last. In other words, it is mandatory to send all values again, the full payload.

When we send a PATCH request, however, we only send the data which we want to update. In other words, we only send the first name to update, no need to send the last name.

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Quite logical the difference between PUT & PATCH w.r.t sending full & partial data for replacing/updating respectively. However, just couple of points as below

Sometimes POST is considered as for updates w.r.t PUT for create Does HTTP mandates/checks for sending full vs partial data in PATCH? Otherwise, PATCH may be quite same as update as in PUT/POST

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