2022/06/30 - Amazon EMR - 2 updated api methods
Changes This release adds support for the ExecutionRoleArn parameter in the AddJobFlowSteps and DescribeStep APIs. Customers can use ExecutionRoleArn to specify the IAM role used for each job they submit using the AddJobFlowSteps API.
{'ExecutionRoleArn': 'string'}
AddJobFlowSteps adds new steps to a running cluster. A maximum of 256 steps are allowed in each job flow.
If your cluster is long-running (such as a Hive data warehouse) or complex, you may require more than 256 steps to process your data. You can bypass the 256-step limitation in various ways, including using SSH to connect to the master node and submitting queries directly to the software running on the master node, such as Hive and Hadoop. For more information on how to do this, see Add More than 256 Steps to a Cluster in the Amazon EMR Management Guide .
A step specifies the location of a JAR file stored either on the master node of the cluster or in Amazon S3. Each step is performed by the main function of the main class of the JAR file. The main class can be specified either in the manifest of the JAR or by using the MainFunction parameter of the step.
Amazon EMR executes each step in the order listed. For a step to be considered complete, the main function must exit with a zero exit code and all Hadoop jobs started while the step was running must have completed and run successfully.
You can only add steps to a cluster that is in one of the following states: STARTING, BOOTSTRAPPING, RUNNING, or WAITING.
Note
The string values passed into HadoopJarStep object cannot exceed a total of 10240 characters.
See also: AWS API Documentation
Request Syntax
client.add_job_flow_steps(
JobFlowId='string',
Steps=[
{
'Name': 'string',
'ActionOnFailure': 'TERMINATE_JOB_FLOW'|'TERMINATE_CLUSTER'|'CANCEL_AND_WAIT'|'CONTINUE',
'HadoopJarStep': {
'Properties': [
{
'Key': 'string',
'Value': 'string'
},
],
'Jar': 'string',
'MainClass': 'string',
'Args': [
'string',
]
}
},
],
ExecutionRoleArn='string'
)
string
[REQUIRED]
A string that uniquely identifies the job flow. This identifier is returned by RunJobFlow and can also be obtained from ListClusters .
list
[REQUIRED]
A list of StepConfig to be executed by the job flow.
(dict) --
Specification for a cluster (job flow) step.
Name (string) -- [REQUIRED]
The name of the step.
ActionOnFailure (string) --
The action to take when the step fails. Use one of the following values:
TERMINATE_CLUSTER - Shuts down the cluster.
CANCEL_AND_WAIT - Cancels any pending steps and returns the cluster to the WAITING state.
CONTINUE - Continues to the next step in the queue.
TERMINATE_JOB_FLOW - Shuts down the cluster. TERMINATE_JOB_FLOW is provided for backward compatibility. We recommend using TERMINATE_CLUSTER instead.
If a cluster's StepConcurrencyLevel is greater than 1 , do not use AddJobFlowSteps to submit a step with this parameter set to CANCEL_AND_WAIT or TERMINATE_CLUSTER . The step is not submitted and the action fails with a message that the ActionOnFailure setting is not valid.
If you change a cluster's StepConcurrencyLevel to be greater than 1 while a step is running, the ActionOnFailure parameter may not behave as you expect. In this case, for a step that fails with this parameter set to CANCEL_AND_WAIT , pending steps and the running step are not canceled; for a step that fails with this parameter set to TERMINATE_CLUSTER , the cluster does not terminate.
HadoopJarStep (dict) -- [REQUIRED]
The JAR file used for the step.
Properties (list) --
A list of Java properties that are set when the step runs. You can use these properties to pass key-value pairs to your main function.
(dict) --
A key-value pair.
Key (string) --
The unique identifier of a key-value pair.
Value (string) --
The value part of the identified key.
Jar (string) -- [REQUIRED]
A path to a JAR file run during the step.
MainClass (string) --
The name of the main class in the specified Java file. If not specified, the JAR file should specify a Main-Class in its manifest file.
Args (list) --
A list of command line arguments passed to the JAR file's main function when executed.
(string) --
string
The Amazon Resource Name (ARN) of the runtime role for a step on the cluster. The runtime role can be a cross-account IAM role. The runtime role ARN is a combination of account ID, role name, and role type using the following format: arn:partition:service:region:account:resource .
For example, arn:aws:iam::1234567890:role/ReadOnly is a correctly formatted runtime role ARN.
dict
Response Syntax
{
'StepIds': [
'string',
]
}
Response Structure
(dict) --
The output for the AddJobFlowSteps operation.
StepIds (list) --
The identifiers of the list of steps added to the job flow.
(string) --
{'Step': {'ExecutionRoleArn': 'string'}}
Provides more detail about the cluster step.
See also: AWS API Documentation
Request Syntax
client.describe_step(
ClusterId='string',
StepId='string'
)
string
[REQUIRED]
The identifier of the cluster with steps to describe.
string
[REQUIRED]
The identifier of the step to describe.
dict
Response Syntax
{
'Step': {
'Id': 'string',
'Name': 'string',
'Config': {
'Jar': 'string',
'Properties': {
'string': 'string'
},
'MainClass': 'string',
'Args': [
'string',
]
},
'ActionOnFailure': 'TERMINATE_JOB_FLOW'|'TERMINATE_CLUSTER'|'CANCEL_AND_WAIT'|'CONTINUE',
'Status': {
'State': 'PENDING'|'CANCEL_PENDING'|'RUNNING'|'COMPLETED'|'CANCELLED'|'FAILED'|'INTERRUPTED',
'StateChangeReason': {
'Code': 'NONE',
'Message': 'string'
},
'FailureDetails': {
'Reason': 'string',
'Message': 'string',
'LogFile': 'string'
},
'Timeline': {
'CreationDateTime': datetime(2015, 1, 1),
'StartDateTime': datetime(2015, 1, 1),
'EndDateTime': datetime(2015, 1, 1)
}
},
'ExecutionRoleArn': 'string'
}
}
Response Structure
(dict) --
This output contains the description of the cluster step.
Step (dict) --
The step details for the requested step identifier.
Id (string) --
The identifier of the cluster step.
Name (string) --
The name of the cluster step.
Config (dict) --
The Hadoop job configuration of the cluster step.
Jar (string) --
The path to the JAR file that runs during the step.
Properties (dict) --
The list of Java properties that are set when the step runs. You can use these properties to pass key-value pairs to your main function.
(string) --
(string) --
MainClass (string) --
The name of the main class in the specified Java file. If not specified, the JAR file should specify a main class in its manifest file.
Args (list) --
The list of command line arguments to pass to the JAR file's main function for execution.
(string) --
ActionOnFailure (string) --
The action to take when the cluster step fails. Possible values are TERMINATE_CLUSTER , CANCEL_AND_WAIT , and CONTINUE . TERMINATE_JOB_FLOW is provided for backward compatibility. We recommend using TERMINATE_CLUSTER instead.
If a cluster's StepConcurrencyLevel is greater than 1 , do not use AddJobFlowSteps to submit a step with this parameter set to CANCEL_AND_WAIT or TERMINATE_CLUSTER . The step is not submitted and the action fails with a message that the ActionOnFailure setting is not valid.
If you change a cluster's StepConcurrencyLevel to be greater than 1 while a step is running, the ActionOnFailure parameter may not behave as you expect. In this case, for a step that fails with this parameter set to CANCEL_AND_WAIT , pending steps and the running step are not canceled; for a step that fails with this parameter set to TERMINATE_CLUSTER , the cluster does not terminate.
Status (dict) --
The current execution status details of the cluster step.
State (string) --
The execution state of the cluster step.
StateChangeReason (dict) --
The reason for the step execution status change.
Code (string) --
The programmable code for the state change reason. Note: Currently, the service provides no code for the state change.
Message (string) --
The descriptive message for the state change reason.
FailureDetails (dict) --
The details for the step failure including reason, message, and log file path where the root cause was identified.
Reason (string) --
The reason for the step failure. In the case where the service cannot successfully determine the root cause of the failure, it returns "Unknown Error" as a reason.
Message (string) --
The descriptive message including the error the Amazon EMR service has identified as the cause of step failure. This is text from an error log that describes the root cause of the failure.
LogFile (string) --
The path to the log file where the step failure root cause was originally recorded.
Timeline (dict) --
The timeline of the cluster step status over time.
CreationDateTime (datetime) --
The date and time when the cluster step was created.
StartDateTime (datetime) --
The date and time when the cluster step execution started.
EndDateTime (datetime) --
The date and time when the cluster step execution completed or failed.
ExecutionRoleArn (string) --
The Amazon Resource Name (ARN) of the runtime role for a step on the cluster. The runtime role can be a cross-account IAM role. The runtime role ARN is a combination of account ID, role name, and role type using the following format: arn:partition:service:region:account:resource .
For example, arn:aws:iam::1234567890:role/ReadOnly is a correctly formatted runtime role ARN.