AWS Big Data Blog

Visualize AWS Cloudtrail Logs using AWS Glue and Amazon Quicksight

Being able to easily visualize AWS CloudTrail logs gives you a better understanding of how your AWS infrastructure is being used. It can also help you audit and review AWS API calls and detect security anomalies inside your AWS account. To do this, you must be able to perform analytics based on your CloudTrail logs.

In this post, I walk through using AWS Glue and AWS Lambda to convert AWS CloudTrail logs from JSON to a query-optimized format dataset in Amazon S3. I then use Amazon Athena and Amazon QuickSight to query and visualize the data.

Solution overview

To process CloudTrail logs, you must implement the following architecture:

CloudTrail delivers log files in an Amazon S3 bucket folder. To correctly crawl these logs, you modify the file contents and folder structure using an Amazon S3-triggered Lambda function that stores the transformed files in an S3 bucket single folder. When the files are in a single folder, AWS Glue scans the data, converts it into Apache Parquet format, and catalogs it to allow for querying and visualization using Amazon Athena and Amazon QuickSight.

Walkthrough

Let’s look at the steps that are required to build the solution.

Set up CloudTrail logs

First, you need to set up a trail that delivers log files to an S3 bucket. To create a trail in CloudTrail, follow the instructions in Creating a Trail.

When you finish, the trail settings page should look like the following screenshot:

In this example, I set up log files to be delivered to the cloudtraillfcaro bucket.

Consolidate CloudTrail reports into a single folder using Lambda

AWS CloudTrail delivers log files using the following folder structure inside the configured Amazon S3 bucket:

AWSLogs/ACCOUNTID/CloudTrail/REGION/YEAR/MONTH/HOUR/filename.json.gz

Additionally, log files have the following structure:

{
    "Records": [{
        "eventVersion": "1.01",
        "userIdentity": {
            "type": "IAMUser",
            "principalId": "AIDAJDPLRKLG7UEXAMPLE",
            "arn": "arn:aws:iam::123456789012:user/Alice",
            "accountId": "123456789012",
            "accessKeyId": "AKIAIOSFODNN7EXAMPLE",
            "userName": "Alice",
            "sessionContext": {
                "attributes": {
                    "mfaAuthenticated": "false",
                    "creationDate": "2014-03-18T14:29:23Z"
                }
            }
        },
        "eventTime": "2014-03-18T14:30:07Z",
        "eventSource": "cloudtrail.amazonaws.com",
        "eventName": "StartLogging",
        "awsRegion": "us-west-2",
        "sourceIPAddress": "72.21.198.64",
        "userAgent": "signin.amazonaws.com",
        "requestParameters": {
            "name": "Default"
        },
        "responseElements": null,
        "requestID": "cdc73f9d-aea9-11e3-9d5a-835b769c0d9c",
        "eventID": "3074414d-c626-42aa-984b-68ff152d6ab7"
    },
    ... additional entries ...
    ]

If AWS Glue crawlers are used to catalog these files as they are written, the following obstacles arise:

  1. AWS Glue identifies different tables per different folders because they don’t follow a traditional partition format.
  2. Based on the structure of the file content, AWS Glue identifies the tables as having a single column of type array.
  3. CloudTrail logs have JSON attributes that use uppercase letters. According to the Best Practices When Using Athena with AWS Glue, it is recommended that you convert these to lowercase.

To have AWS Glue catalog all log files in a single table with all the columns describing each event, implement the following Lambda function:

from __future__ import print_function
import json
import urllib
import boto3
import gzip

s3 = boto3.resource('s3')
client = boto3.client('s3')

def convertColumntoLowwerCaps(obj):
    for key in obj.keys():
        new_key = key.lower()
        if new_key != key:
            obj[new_key] = obj[key]
            del obj[key]
    return obj


def lambda_handler(event, context):

    bucket = event['Records'][0]['s3']['bucket']['name']
    key = urllib.unquote_plus(event['Records'][0]['s3']['object']['key'].encode('utf8'))
    print(bucket)
    print(key)
    try:
        newKey = 'flatfiles/' + key.replace("/", "")
        client.download_file(bucket, key, '/tmp/file.json.gz')
        with gzip.open('/tmp/out.json.gz', 'w') as output, gzip.open('/tmp/file.json.gz', 'rb') as file:
            i = 0
            for line in file: 
                for record in json.loads(line,object_hook=convertColumntoLowwerCaps)['records']:
            		if i != 0:
            		    output.write("\n")
            		output.write(json.dumps(record))
            		i += 1
        client.upload_file('/tmp/out.json.gz', bucket,newKey)
        return "success"
    except Exception as e:
        print(e)
        print('Error processing object {} from bucket {}. Make sure they exist and your bucket is in the same region as this function.'.format(key, bucket))
        raise e

The function goes over each element of the records array, changes uppercase letters to lowercase in column names, and inserts each element of the array as a single line of a new file. The new file is saved inside a flatfiles folder created by the function without any subfolders in the S3 bucket.

The function should have a role containing a policy with at least the following permissions:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": [
                "s3:*"
            ],
            "Resource": [
                "arn:aws:s3:::cloudtraillfcaro/*",
                "arn:aws:s3:::cloudtraillfcaro"
            ],
            "Effect": "Allow"
        }
    ]
}

In this example, CloudTrail delivers logs to the cloudtraillfcaro bucket. Make sure that you replace this name with your bucket name in the policy. For more information about how to work with inline policies, see Working with Inline Policies.

After the Lambda function is created, you can set up the following trigger using the Triggers tab on the AWS Lambda console.

Choose Add trigger, and choose S3 as a source of the trigger.

After choosing the source, configure the following settings:

In the trigger, any file that is written to the path for the log files—which in this case is AWSLogs/119582755581/CloudTrail/—is processed. Make sure that the Enable trigger check box is selected and that the bucket and prefix parameters match your use case.

After you set up the function and receive log files, the bucket (in this case cloudtraillfcaro) should contain the processed files inside the flatfiles folder.

Catalog source data

Once the files are processed by the Lambda function, set up a crawler named cloudtrail to catalog them.

The crawler must point to the flatfiles folder.

All the crawlers and AWS Glue jobs created for this solution must have a role with the AWSGlueServiceRole managed policy and an inline policy with permissions to modify the S3 buckets used on the Lambda function. For more information, see Working with Managed Policies.

The role should look like the following:

In this example, the inline policy named s3perms contains the permissions to modify the S3 buckets.

After you choose the role, you can schedule the crawler to run on demand.

A new database is created, and the crawler is set to use it. In this case, the cloudtrail database is used for all the tables.

After the crawler runs, a single table should be created in the catalog with the following structure:

The table should contain the following columns:

Create and run the AWS Glue job

To convert all the CloudTrail logs to a columnar store in Parquet, set up an AWS Glue job by following these steps.

Upload the following script into a bucket in Amazon S3:

import sys
from awsglue.transforms import *
from awsglue.utils import getResolvedOptions
from pyspark.context import SparkContext
from awsglue.context import GlueContext
from awsglue.job import Job
import boto3
import time

## @params: [JOB_NAME]
args = getResolvedOptions(sys.argv, ['JOB_NAME'])

sc = SparkContext()
glueContext = GlueContext(sc)
spark = glueContext.spark_session
job = Job(glueContext)
job.init(args['JOB_NAME'], args)

datasource0 = glueContext.create_dynamic_frame.from_catalog(database = "cloudtrail", table_name = "flatfiles", transformation_ctx = "datasource0")
resolvechoice1 = ResolveChoice.apply(frame = datasource0, choice = "make_struct", transformation_ctx = "resolvechoice1")
relationalized1 = resolvechoice1.relationalize("trail", args["TempDir"]).select("trail")
datasink = glueContext.write_dynamic_frame.from_options(frame = relationalized1, connection_type = "s3", connection_options = {"path": "s3://cloudtraillfcaro/parquettrails"}, format = "parquet", transformation_ctx = "datasink4")
job.commit()

In the example, you load the script as a file named cloudtrailtoparquet.py. Make sure that you modify the script and update the “{"path": "s3://cloudtraillfcaro/parquettrails"}” with the destination in which you want to store your results.

After uploading the script, add a new AWS Glue job. Choose a name and role for the job, and choose the option of running the job from An existing script that you provide.

To avoid processing the same data twice, enable the Job bookmark setting in the Advanced properties section of the job properties.

Choose Next twice, and then choose Finish.

If logs are already in the flatfiles folder, you can run the job on demand to generate the first set of results.

Once the job starts running, wait for it to complete.

When the job is finished, its Run status should be Succeeded. After that, you can verify that the Parquet files are written to the Amazon S3 location.

Catalog results

To be able to process results from Athena, you can use an AWS Glue crawler to catalog the results of the AWS Glue job.

In this example, the crawler is set to use the same database as the source named cloudtrail.

You can run the crawler using the console. When the crawler finishes running and has processed the Parquet results, a new table should be created in the AWS Glue Data Catalog. In this example, it’s named parquettrails.

The table should have the classification set to parquet.

It should have the same columns as the flatfiles table, with the exception of the struct type columns, which should be relationalized into several columns:

In this example, notice how the requestparameters column, which was a struct in the original table (flatfiles), was transformed to several columns—one for each key value inside it. This is done using a transformation native to AWS Glue called relationalize.

Query results with Athena

After crawling the results, you can query them using Athena. For example, to query what events took place in the time frame between 2017-10-23t12:00:00 and 2017-10-23t13:00, use the following select statement:

select *
from cloudtrail.parquettrails
where eventtime > '2017-10-23T12:00:00Z' AND eventtime < '2017-10-23T13:00:00Z'
order by eventtime asc;

Be sure to replace cloudtrail.parquettrails with the names of your database and table that references the Parquet results. Replace the datetimes with an hour when your account had activity and was processed by the AWS Glue job.

Visualize results using Amazon QuickSight

Once you can query the data using Athena, you can visualize it using Amazon QuickSight. Before connecting Amazon QuickSight to Athena, be sure to grant QuickSight access to Athena and the associated S3 buckets in your account. For more information, see Managing Amazon QuickSight Permissions to AWS Resources. You can then create a new data set in Amazon QuickSight based on the Athena table that you created.

After setting up permissions, you can create a new analysis in Amazon QuickSight by choosing New analysis.

Then add a new data set.

Choose Athena as the source.

Give the data source a name (in this case, I named it cloudtrail).

Choose the name of the database and the table referencing the Parquet results.

Then choose Visualize.

After that, you should see the following screen:

Now you can create some visualizations. First, search for the sourceipaddress column, and drag it to the AutoGraph section.

You can see a list of the IP addresses that you have used to interact with AWS. To review whether these IP addresses have been used from IAM users, internal AWS services, or roles, use the type value that is inside the useridentity field of the original log files. Thanks to the relationalize transformation, this value is available as the useridentity.type column. After the column is added into the Group/Color box, the visualization should look like the following:

You can now see and distinguish the most used IPs and whether they are used from roles, AWS services, or IAM users.

After following all these steps, you can use Amazon QuickSight to add different columns from CloudTrail and perform different types of visualizations. You can build operational dashboards that continuously monitor AWS infrastructure usage and access. You can share those dashboards with others in your organization who might need to see this data.

Summary

In this post, you saw how you can use a simple Lambda function and an AWS Glue script to convert text files into Parquet to improve Athena query performance and data compression. The post also demonstrated how to use AWS Lambda to preprocess files in Amazon S3 and transform them into a format that is recognizable by AWS Glue crawlers.

This example, used AWS CloudTrail logs, but you can apply the proposed solution to any set of files that after preprocessing, can be cataloged by AWS Glue.


Additional Reading

Learn how to Harmonize, Query, and Visualize Data from Various Providers using AWS Glue, Amazon Athena, and Amazon QuickSight.


About the Author

Luis Caro is a Big Data Consultant for AWS Professional Services. He works with our customers to provide guidance and technical assistance on big data projects, helping them improving the value of their solutions when using AWS.