Chapter 5. API requests in various languages
You can review the following examples of sending API requests to Red Hat Satellite from curl, Ruby, or Python.
5.1. Calling the API in curl
You can use curl
with the Satellite API to perform various tasks.
Red Hat Satellite requires the use of HTTPS, and by default a certificate for host identification. If you have not added the Satellite Server certificate as described in Section 4.1, “SSL authentication overview”, then you can use the --insecure
option to bypass certificate checks.
For user authentication, you can use the --user
option to provide Satellite user credentials in the form --user username:password
or, if you do not include the password, the command prompts you to enter it. To reduce security risks, do not include the password as part of the command, because it then becomes part of your shell history. Examples in this section include the password only for the sake of simplicity.
Be aware that if you use the --silent
option, curl
does not display a progress meter or any error messages.
Examples in this chapter use the Python json.tool
module to format the output.
5.1.1. Passing JSON data to the API request
You can pass data to Satellite Server with the API request. The data must be in JSON format. When specifying JSON data with the --data
option, you must set the following HTTP headers with the --header
option:
--header "Accept:application/json" \ --header "Content-Type:application/json"
Use one of the following options to include data with the --data
option.
JSON-formatted string
Enclose the quoted JSON-formatted data in curly braces {}
. When passing a value for a JSON type parameter, you must escape quotation marks "
with backslashes \
. For example, within curly braces, you must format "Example JSON Variable"
as \"Example JSON Variable\"
:
--data {"id":44, "smart_class_parameter":{"override":"true", "parameter_type":"json", "default_value":"{\"GRUB_CMDLINE_LINUX\": {\"audit\":\"1\",\"crashkernel\":\"true\"}}"}}
JSON-formatted file
The unquoted JSON-formatted data enclosed in a file and specified by the @
sign and the filename. For example:
--data @file.json
Using external files for JSON formatted data has the following advantages:
- You can use your favorite text editor.
- You can use syntax checker to find and avoid mistakes.
- You can use tools to check the validity of JSON data or to reformat it.
Use the json_verify
tool to check the validity of the JSON file:
$ json_verify < file.json
5.1.2. Retrieving a list of resources
This section outlines how to use curl
with the Satellite 6 API to request information from Satellite. These examples include both requests and responses. Expect different results for each deployment.
Listing users
This example is a basic request that returns a list of Satellite resources, Satellite users in this case. Such requests return a list of data wrapped in metadata, while other request types only return the actual object.
Example request:
$ curl --request GET --user My_User_Name:My_Password \ https://satellite.example.com/api/users | python3 -m json.tool
Example response:
{ "page": 1, "per_page": 20, "results": [ { "admin": false, "auth_source_id": 1, "auth_source_name": "Internal", "created_at": "2018-09-21 08:59:22 UTC", "default_location": null, "default_organization": null, "description": "", "effective_admin": false, "firstname": "", "id": 5, "last_login_on": "2018-09-21 09:03:25 UTC", "lastname": "", "locale": null, "locations": [], "login": "test", "mail": "example@domain.com", "organizations": [ { "id": 1, "name": "Default Organization" } ], "ssh_keys": [], "timezone": null, "updated_at": "2018-09-21 09:04:45 UTC" }, { "admin": true, "auth_source_id": 1, "auth_source_name": "Internal", "created_at": "2018-09-20 07:09:41 UTC", "default_location": null, "default_organization": { "description": null, "id": 1, "name": "Default Organization", "title": "Default Organization" }, "description": "", "effective_admin": true, "firstname": "Admin", "id": 4, "last_login_on": "2018-12-07 07:31:09 UTC", "lastname": "User", "locale": null, "locations": [ { "id": 2, "name": "Default Location" } ], "login": "admin", "mail": "root@example.com", "organizations": [ { "id": 1, "name": "Default Organization" } ], "ssh_keys": [], "timezone": null, "updated_at": "2018-11-14 08:19:46 UTC" } ], "search": null, "sort": { "by": null, "order": null }, "subtotal": 2, "total": 2 }
5.1.3. Creating and modifying resources
You can use curl
to manipulate resources on your Satellite Server. API calls to Satellite require data in json
format. For more information, see Section 5.1.1, “Passing JSON data to the API request”.
Creating a user
This example creates a user by providing required information in the --data
option.
Example request:
$ curl --header "Accept:application/json" \ --header "Content-Type:application/json" --request POST \ --user My_User_Name:My_Password \ --data "{\"firstname\":\"Test Name\",\"mail\":\"test@example.com\",\"login\":\"test_user\",\"password\":\"password123\",\"auth_source_id\":1}" \ https://satellite.example.com/api/users | python3 -m json.tool
Modifying a user
This example modifies given name and login of the test_user
that was created in Creating a user.
Example request:
$ curl --header "Accept:application/json" \ --header "Content-Type:application/json" --request PUT \ --user My_User_Name:My_Password \ --data "{\"firstname\":\"New Test Name\",\"mail\":\"test@example.com\",\"login\":\"new_test_user\",\"password\":\"password123\",\"auth_source_id\":1}" \ https://satellite.example.com/api/users/8 | python3 -m json.tool
5.2. Calling the API in Ruby
You can use Ruby with the Satellite API to perform various tasks.
These are example scripts and commands. Ensure you review these scripts carefully before use, and replace any variables, user names, passwords, and other information to suit your own deployment.
5.2.1. Creating objects by using Ruby
This script connects to the Red Hat Satellite 6 API and creates an organization, and then creates three lifecycle environments in the organization. If the organization already exists, the script uses that organization. If any of the lifecycle environments already exist in the organization, the script raises an error and quits.
#!/usr/bin/ruby require 'rest-client' require 'json' url = 'https://satellite.example.com/api/v2/' katello_url = "#{url}/katello/api/v2/" $username = 'admin' $password = 'changeme' org_name = "MyOrg" environments = [ "Development", "Testing", "Production" ] # Performs a GET by using the passed URL location def get_json(location) response = RestClient::Request.new( :method => :get, :url => location, :user => $username, :password => $password, :headers => { :accept => :json, :content_type => :json } ).execute JSON.parse(response.to_str) end # Performs a POST and passes the data to the URL location def post_json(location, json_data) response = RestClient::Request.new( :method => :post, :url => location, :user => $username, :password => $password, :headers => { :accept => :json, :content_type => :json}, :payload => json_data ).execute JSON.parse(response.to_str) end # Creates a hash with ids mapping to names for an array of records def id_name_map(records) records.inject({}) do |map, record| map.update(record['id'] => record['name']) end end # Get list of existing organizations orgs = get_json("#{katello_url}/organizations") org_list = id_name_map(orgs['results']) if !org_list.has_value?(org_name) # If our organization is not found, create it puts "Creating organization: \t#{org_name}" org_id = post_json("#{katello_url}/organizations", JSON.generate({"name"=> org_name}))["id"] else # Our organization exists, so let's grab it org_id = org_list.key(org_name) puts "Organization \"#{org_name}\" exists" end # Get list of organization's lifecycle environments envs = get_json("#{katello_url}/organizations/#{org_id}/environments") env_list = id_name_map(envs['results']) prior_env_id = env_list.key("Library") # Exit the script if at least one life cycle environment already exists environments.each do |e| if env_list.has_value?(e) puts "ERROR: One of the Environments is not unique to organization" exit end end # Create life cycle environments environments.each do |environment| puts "Creating environment: \t#{environment}" prior_env_id = post_json("#{katello_url}/organizations/#{org_id}/environments", JSON.generate({"name" => environment, "organization_id" => org_id, "prior_id" => prior_env_id}))["id"] end
5.2.2. Using apipie bindings with Ruby
Apipie bindings are the Ruby bindings for apipie documented API calls. They fetch and cache the API definition from Satellite and then generate API calls as needed.
#!/usr/bin/ruby require 'apipie-bindings' org_name = "MyOrg" environments = [ "Development", "Testing", "Production" ] # Create an instance of apipie bindings @api = ApipieBindings::API.new({ :uri => 'https://satellite.example.com/', :username => 'admin', :password => 'changeme', :api_version => 2 }) # Performs an API call with default options def call_api(resource_name, action_name, params = {}) http_headers = {} apipie_options = { :skip_validation => true } @api.resource(resource_name).call(action_name, params, http_headers, apipie_options) end # Creates a hash with IDs mapping to names for an array of records def id_name_map(records) records.inject({}) do |map, record| map.update(record['id'] => record['name']) end end # Get list of existing organizations orgs = call_api(:organizations, :index) org_list = id_name_map(orgs['results']) if !org_list.has_value?(org_name) # If our organization is not found, create it puts "Creating organization: \t#{org_name}" org_id = call_api(:organizations, :create, {'organization' => { :name => org_name }})['id'] else # Our organization exists, so let's grab it org_id = org_list.key(org_name) puts "Organization \"#{org_name}\" exists" end # Get list of organization's life cycle environments envs = call_api(:lifecycle_environments, :index, {'organization_id' => org_id}) env_list = id_name_map(envs['results']) prior_env_id = env_list.key("Library") # Exit the script if at least one life cycle environment already exists environments.each do |e| if env_list.has_value?(e) puts "ERROR: One of the Environments is not unique to organization" exit end end # Create life cycle environments environments.each do |environment| puts "Creating environment: \t#{environment}" prior_env_id = call_api(:lifecycle_environments, :create, {"name" => environment, "organization_id" => org_id, "prior_id" => prior_env_id })['id'] end
5.3. Calling the API in Python
You can use Python with the Satellite API to perform various tasks.
These are example scripts and commands. Ensure you review these scripts carefully before use, and replace any variables, user names, passwords, and other information to suit your own deployment.
Example scripts in this section do not use SSL verification for interacting with the REST API.
5.3.1. Creating objects by using Python
This script connects to the Red Hat Satellite 6 API and creates an organization, and then creates three environments in the organization. If the organization already exists, the script uses that organization. If any of the environments already exist in the organization, the script raises an error and quits.
Python 3 example
#!/usr/bin/python3 import json import sys try: import requests except ImportError: print("Please install the python-requests module.") sys.exit(-1) # URL to your Satellite Server URL = "https://satellite.example.com" FOREMAN_API = f"{URL}/api/" KATELLO_API = f"{URL}/katello/api/" POST_HEADERS = {'content-type': 'application/json'} # Default credentials to login to Satellite 6 USERNAME = "admin" PASSWORD = "changeme" # Ignore SSL for now SSL_VERIFY = False # Name of the organization to be either created or used ORG_NAME = "MyOrg" # Name for life cycle environments to be either created or used ENVIRONMENTS = ["Development", "Testing", "Production"] def get_json(location): """ Performs a GET by using the passed URL location """ r = requests.get(location, auth=(USERNAME, PASSWORD), verify=SSL_VERIFY) return r.json() def post_json(location, json_data): """ Performs a POST and passes the data to the URL location """ result = requests.post( location, data=json_data, auth=(USERNAME, PASSWORD), verify=SSL_VERIFY, headers=POST_HEADERS ) return result.json() def main(): """ Main routine that creates or re-uses an organization and life cycle environments. If life cycle environments already exist, exit out. """ # Check if our organization already exists org = get_json(f"{FOREMAN_API}/organizations/{ORG_NAME}") # If our organization is not found, create it if org.get('error', None): org_id = post_json( f"{FOREMAN_API}/organizations/", json.dumps({"name": ORG_NAME}) )["id"] print("Creating organization:\t" + ORG_NAME) else: # Our organization exists, so let's grab it org_id = org['id'] print(f"Organization '{ORG_NAME}' exists.") # Now, let's fetch all available life cycle environments for this org... envs = get_json( f"{KATELLO_API}/organizations/{org_id}/environments/" ) # ...and add them to a dictionary, with respective 'Prior' environment prior_env_id = 0 env_list = {} for env in envs['results']: env_list[env['id']] = env['name'] prior_env_id = env['id'] if env['name'] == "Library" else prior_env_id # Exit the script if at least one life cycle environment already exists if all(environment in env_list.values() for environment in ENVIRONMENTS): print("ERROR: One of the Environments is not unique to organization") sys.exit(-1) # Create life cycle environments for environment in ENVIRONMENTS: new_env_id = post_json( f"{KATELLO_API}/organizations/{org_id}/environments/", json.dumps({ "name": environment, "organization_id": org_id, "prior": prior_env_id }) )["id"] print("Creating environment:\t" + environment) prior_env_id = new_env_id if __name__ == "__main__": main()
5.3.2. Requesting information from the API by using Python
This is an example script that uses Python for various API requests.
Python 3 example
#!/usr/bin/env python3 import json import sys try: import requests except ImportError: print("Please install the python-requests module.") sys.exit(-1) HOSTNAME = "satellite.example.com" # URL for the API to your Satellite Server FOREMAN_API = f"https://{HOSTNAME}/api/" KATELLO_API = f"https://{HOSTNAME}/katello/api/v2/" POST_HEADERS = {'content-type': 'application/json'} # Default credentials to login to Satellite 6 USERNAME = "admin" PASSWORD = "password" # Ignore SSL for now SSL_VERIFY = False #SSL_VERIFY = "./path/to/CA-certificate.crt" # Put the path to your CA certificate here to allow SSL_VERIFY def get_json(url): # Performs a GET by using the passed URL location r = requests.get(url, auth=(USERNAME, PASSWORD), verify=SSL_VERIFY) return r.json() def get_results(url): jsn = get_json(url) if jsn.get('error'): print("Error: " + jsn['error']['message']) else: if jsn.get('results'): return jsn['results'] elif 'results' not in jsn: return jsn else: print("No results found") return None def display_all_results(url): results = get_results(url) if results: print(json.dumps(results, indent=4, sort_keys=True)) def display_info_for_hosts(url): hosts = get_results(url) if hosts: print(f"{'ID':10}{'Name':40}{'IP':30}{'Operating System':30}") for host in hosts: print(f"{str(host['id']):10}{host['name']:40}{str(host['ip']):30}{str(host['operatingsystem_name']):30}") def display_info_for_subs(url): subs = get_results(url) if subs: print(f"{'ID':10}{'Name':90}{'Start Date':30}") for sub in subs: print(f"{str(sub['id']):10}{sub['name']:90}{str(sub['start_date']):30}") def main(): host = HOSTNAME print(f"Displaying all info for host {host} ...") display_all_results(FOREMAN_API + 'hosts/' + host) print(f"Displaying all facts for host {host} ...") display_all_results(FOREMAN_API + f'hosts/{host}/facts') host_pattern = 'example' print(f"Displaying basic info for hosts matching pattern '{host_pattern}'...") display_info_for_hosts(FOREMAN_API + 'hosts?per_page=1&search=name~' + host_pattern) print(f"Displaying basic info for subscriptions") display_info_for_subs(KATELLO_API + 'subscriptions') environment = 'production' print(f"Displaying basic info for hosts in environment {environment}...") display_info_for_hosts(FOREMAN_API + 'hosts?search=environment=' + environment) if __name__ == "__main__": main()