A curl tutorial using GitHub's API

curl.md

Introduction

An introduction to curl using GitHub's API

The Basics

Makes a basic GET request to the specifed URI

curl https://api.github.com/users/caspyin

Includes HTTP-Header information in the output

curl --include https://api.github.com/users/caspyin

Pass user credential to basic auth to access protected resources like a users starred gists, or private info associated with their profile

curl --user "caspyin:PASSWD" https://api.github.com/gists/starred
curl --user "caspyin:PASSWD" https://api.github.com/users/caspyin

Passing just the username without the colon (:) will cause you to be prompted for your account password. This avoids having your password in your command line history

curl --user "caspyin" https://api.github.com/users/caspyin

POST

Use the --request (-X) flag along with --data (-d) to POST data

curl --user "caspyin" --request POST --data '{"description":"Created via API","public":"true","files":{"file1.txt":{"content":"Demo"}}' https://api.github.com/gists

curl --user "caspyin" -X POST --data '{"description":"Created via API","public":"true","files":{"file1.txt":{"content":"Demo"}}' https://api.github.com/gists

Of course --data implies POST so you don't have to also specify the --request flag

curl --user "caspyin" --data '{"description":"Created via API","public":"true","files":{"file1.txt":{"content":"Demo"}}' https://api.github.com/gists

Here is an example that uses the old GitHub API (v2). You can use multiple --data flags

curl --data "login=caspyin" --data "token=TOKEN" https://github.com/api/v2/json/user/show/caspyin

The post data gets combined into one so you can also just combine them yourself into a single --data flag

curl --data "login=caspyin&token=TOKEN" https://github.com/api/v2/json/user/show/caspyin

You can tell curl to read from a file (@) to POST data

curl --user "caspyin" --data @data.txt https://api.github.com/gists 

Or it can read from STDIN (@-)

curl --user "caspyin" --data @- https://api.github.com/gists
{
  "description":"Test",
  "public":false,
  "files": {
    "file1.txt": {
      "content":"Demo"
    }
  }
}
end with ctrl+d

Headers

Often when POSTing data you'll need to add headers for things like auth tokens or setting the content type. You can set a header using -H.

curl -H "Content-Type: application/json" -H "authToken: 349ab29a-xtab-423b-a5hc-5623bc39b8c8" --data '{}' https://api.example.com/endpoint

Dealing with HTTPS

If an API doens't have an SSL cert but is using HTTPS you can tell curl to ignore the security by using --insecure. Be warned this is a very "insecure" thing to do and is only listed here for "educational purposes".

curl --insecure https://api.example.com/endpoint

For my own reference mostly, here is where I first learned about using --insecure rvm/rvm#1684

OAuth

The first thing to know is that your API Token (found in https://github.com/settings/admin) is not the same token used by OAuth. They are different tokens and you will need to generate an OAuth token to be authorized.

Follow the API's instructions at http://developer.github.com/v3/oauth/ under the sections "Non-Web Application Flow" and "Create a new authorization" to become authorized.

Note: Use Basic Auth once to create an OAuth2 token http://developer.github.com/v3/oauth/#oauth-authorizations-api

curl https://api.github.com/authorizations \
--user "caspyin" \
--data '{"scopes":["gist"],"note":"Demo"}'

This will prompt you for your GitHub password and return your OAuth token in the response. It will also create a new Authorized application in your account settings https://github.com/settings/applications

Now that you have the OAuth token there are two ways to use the token to make requests that require authentication (replace "OAUTH-TOKEN" with your actual token)

curl https://api.github.com/gists/starred?access_token=OAUTH-TOKEN
curl -H "Authorization: token OAUTH-TOKEN" https://api.github.com/gists/starred

List the authorizations you already have

curl --user "caspyin" https://api.github.com/authorizations

Resources

• HTTParty - Ruby library that makes it easy to create HTTP requests https://github.com/jnunemaker/httparty
• Hurl IT - An open source web application to play with curl options http://hurl.it