man curl:

   -H/--header <header>
          (HTTP)  Extra header to use when getting a web page. You may specify
          any number of extra headers. Note that if you should  add  a  custom
          header that has the same name as one of the internal ones curl would
          use, your externally set header will be used instead of the internal
          one.  This  allows  you  to make even trickier stuff than curl would
          normally do. You should not replace internally set  headers  without
          knowing  perfectly well what you're doing. Remove an internal header
          by giving a replacement without content on the  right  side  of  the
          colon, as in: -H "Host:".

          curl  will  make sure that each header you add/replace get sent with
          the proper end of line marker, you should thus not  add  that  as  a
          part  of the header content: do not add newlines or carriage returns
          they will only mess things up for you.

          See also the -A/--user-agent and -e/--referer options.

          This option can be used multiple times to add/replace/remove  multi-
          ple headers.

Example 1: Single Header

curl --header "X-MyHeader: 123" www.google.com

Example 2: Multiple Headers

curl --header "Accept: text/javascript" --header "X-Test: hello" -v www.google.com

You can see the request that curl sent by adding the -v option.

GET:

with JSON:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" http://hostname/resource

with XML:

curl -H "Accept: application/xml" -H "Content-Type: application/xml" -X GET http://hostname/resource

POST:

For posting data:

curl --data "param1=value1&param2=value2" http://hostname/resource

For file upload:

curl --form "fileupload=@filename.txt" http://hostname/resource

RESTful HTTP Post:

curl -X POST -d @filename http://hostname/resource

For logging into a site (auth):

curl -d "username=admin&password=admin&submit=Login" --dump-header headers http://localhost/Login
curl -L -b headers http://localhost/

In PHP:

curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue'));

or you can set multiple:

curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue', 'HeaderName2:HeaderValue2'));

Use -H or --header.

Man page: http://curl.haxx.se/docs/manpage.html#-H

GET (multiple parameters):

curl -X  GET "http://localhost:3000/action?result1=gh&result2=ghk"

or

curl --request  GET "http://localhost:3000/action?result1=gh&result2=ghk"

or

curl  "http://localhost:3000/action?result1=gh&result2=ghk"

or

curl -i -H "Application/json" -H "Content-type: application/json"  "http://localhost:3000/action?result1=gh&result2=ghk"

You can also send multiple headers, data (JSON for example), and specify Call method (POST,GET) into a single CUrl call like this:

curl -X POST(Get or whatever) \
  http://your_url.com/api/endpoint \
  -H 'Content-Type: application/json' \
  -H 'header-element1: header-data1' \
  -H 'header-element2: header-data2' \

......more headers................

  -d '{
  "JsonExArray": [
    {
      "json_prop": "1",
    },
    {
      "json_prop": "2",
    }
  ]
}'

I use Postman.

Execute whatever call you want to do. Then, postman provides a handy tool to show the curl code .

Run it in the terminal.

I've switched from curl to Httpie; the syntax looks like:

http http://myurl HeaderName:value

In case you want send your custom headers, you can do it this way:

curl -v -H @{'custom_header'='custom_header_value'} http://localhost:3000/action?result1=gh&result2=ghk

In anaconda envirement through windows the commands should be: GET, for ex:

curl.exe http://127.0.0.1:5000/books 

Post or Patch the data for ex:

curl.exe http://127.0.0.1:5000/books/8 -X PATCH -H "Content-Type: application/json" -d '{\"rating\":\"2\"}' 

PS: Add backslash for json data to avoid this type of error => Failed to decode JSON object: Expecting value: line 1 column 1 (char 0)

and use curl.exe instead of curl only to avoid this problem:

Invoke-WebRequest : Cannot bind parameter 'Headers'. Cannot convert the "Content-Type: application/json" value of type
"System.String" to type "System.Collections.IDictionary".
At line:1 char:48
+ ... 0.1:5000/books/8 -X PATCH -H "Content-Type: application/json" -d '{\" ...
+                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidArgument: (:) [Invoke-WebRequest], ParameterBindingException
    + FullyQualifiedErrorId : CannotConvertArgumentNoMessage,Microsoft.PowerShell.Commands.InvokeWebRequestCommand

Here are the some curl commands for most common http methods.

Domain Object considered here is

@Data
@NoArgsConstructor
@AllArgsConstructor
@Document
@Validated
public class Movie {
    @Id
    private String id;
    private String name;
    @NotNull
    private Integer year;
    @NotNull
    private List<String> cast;
    private LocalDate release_date;
}

POST-CREATE-MOVIE

curl -i \
-d '{"id":1, "name": "Dhoom", "year":2004,"cast":["John Abraham", "Abhishek Bachan"],"release_date": "2004-06-15"}' \
-H "Content-Type: application/json" \
-X POST http://localhost:8080/v1/movies

GET-ALL-MOVIES

curl -i http://localhost:8080/v1/movies

GET-MOVIE-BY-ID

curl -i http://localhost:8080/v1/movies/1

PUT-UPDATE-MOVIE

curl -i \
-d '{"id":1, "name": "Dhoom", "year":2005,"cast":["John Abhraham", "Abhishek Bachhan", "Uday Chopra", "Isha Deol"],"release_date": "2005-03-25"}' \
-H "Content-Type: application/json" \
-X PUT http://localhost:8080/v1/movies/1

DELETE-MOVIE

curl -i -X DELETE http://localhost:8080/v1/movies/1