demo_utils.ambari module¶

A module which houses Ambari - an instantiable Ambari client

Each call to the Ambari client uses the curl_client module. The output from the curl client is send through the static load_output method to keep the return format similar for requests which fail.

See the load_ouput method for some more information

Response with Error

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{
  "message": "curl (6) Could not connect to host"
}

Response without error (from something like get_service)

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{
  "href" : "http://sandbox.hortonworks.com:8080/api/v1/clusters/Sandbox/services/YARN?fields=ServiceInfo",
  "ServiceInfo" : {
    "cluster_name" : "Sandbox",
    "maintenance_state" : "OFF",
    "service_name" : "YARN",
    "state" : "INSTALLED"
  }
}

class demo_utils.ambari.Ambari(username='', password='', proto='http', server='127.0.0.1', port=8080, service_wait_time=60, config='')¶

Initalize the Ambari client

Parameters:

username (str, optional) – username to use for authentication (should have admin access) password (str, optional) – password to use for authentication (should have admin access) proto (str, optional) – Must be one of ‘http’ or ‘https’. Defines which protocol to use. Defaults to ‘http’ server (str, optional) – The hostname (or IP) of the Ambari server. Defaults to 127.0.0.1. port (int, optional) – The port that ambari server is running on. Defaults to 8080 service_wait_time (int, optional) – The time (in seconds) we should before we decide a service has failed changing states. config (dict, optional) – This is a dictionary object which should contain the any of the keys ‘username’, ‘password’, ‘proto’, ‘server’, ‘port’, or ‘service_wait_time’. Given the config here you can set any of the client’s parameters through this object. However, when using this, the config object will override any of the specific arguments passed.

Returns:

N/A

get_cluster_info(cluster_name, query='')¶

Get all of the information about a current cluster. Equivalent to GET /api/v1/clusters/{cluster_name}

Parameters:	cluster_name (string) – The name of the cluster to query.

get_clusters(query='')¶

Returns a list of clusters from the given Ambari host/port. Equivalent to GET /api/v1/clusters

Parameters:	query (string, optional) – A formatted query string which is appended to the end of the request URL (advanced). Used for filtering results.
Returns:	An object which is created after being passed to self.load_output
Return type:	dict

get_service(cluster_name, service_name, query='')¶

Get all of the information about a single service from the Ambari API. Equivalent to GET /api/v1/clusters/{CLUSTER}/services/{SERVICE}

Parameters:	cluster_name (str) – The name of the cluster to query service_name (str) – The name of the service we want to query. query (str, optional) – A query to filter results. Will be appended to the end of the string. i.e field1=serviceState&field2=AnotherVal
Returns:	An object converted from the JSON response of the Ambari API. Message will denote otherwise if the request was not successful
Return type:	dict

get_services(cluster_name, query='')¶

Get a list of services installed on a cluster. Equivalent to GET /api/v1/clusters/{cluster_name}/services

Parameters:	cluster_name (string) – The name of the cluster to query query (string, optional) – A query to be appended to the url for filtering results
Returns:	a dictionary object built from the HTTP response and self.load_output
Return type:	dict

static load_output(output)¶

Load the output from the curl_client into an object

The idea behind this function is to try and keep the same behavior on failed requests across the entire client.

Parameters:	output – (str): The output from a curl_client action
Returns:	a dictionary object created from the JSON response of the Ambari request. If the request was unsuccessful a message attribute will be present containing the error from the curl request.
Return type:	dict
Raises:	ValueError – This is raised when an object can’t be converted into JSON

password = ''¶

class variable

port = ''¶

class variable

proto = ''¶

class variable

server = ''¶

class variable

service_action(cluster_name, service_name, action, queue=False)¶

Executes an action on a given service inside of a cluster. Action must be one of START, STOP, or RESTART

Parameters:	cluster_name (str) – the name of the cluster that the service resides in service_name (str) – the name of the service which we are acting on action (str) – A string of ‘START’, ‘STOP’, or ‘RESTART’ queue (bool) – False when we want the function to wait to continue until the service starts. True when we simply just want to add the function to the Ambari task queue. Defaults to False. Note: Does not guarantee the service will complete successfully.
Returns:	True is the action is completed successfully, False if otherwise.
Return type:	bool
Raises:	ValueError – Raised when the action is not one of START/STOP/RESTART

set_password(password)¶

Set the authentication password

Parameters:	password (str) –
Returns:	N/A

set_port(port)¶

Set the port to be used

Parameters:	port (int) –
Returns:	N/A

set_proto(proto)¶

Set the http protocol to be used

Parameters:	proto (str) –
Returns:	N/A

set_server(server)¶

Set the server/hostname which the client connects to

Parameters:	server (str) –
Returns:	N/A

set_service_wait_time(wait_time)¶

Set the timeout (in seconds) when waiting for a service to change states. i.e to Start/Stop/Restart a service.

Parameters:	wait_time (int) –
Returns:	N/A

set_username(user)¶

Set the authentication username

Parameters:	user (str) –
Returns:	N/A

username = ''¶

class variable