# Amazon CloudWatch ( YAML )
Apica Ascent connects to Amazon CloudWatch using the boto3 client with the help of the AWS CloudWatch data source making it easy for you to query CloudWatch metrics using its natural syntax, analyze, monitor, and create Visualization of data.
{% hint style="info" %}
Before you query your CloudWatch data, you should set up authentication credentials. Credentials for your AWS account can be found in the IAM Console. You can create or use an existing user. Go to manage access keys and generate a new set of keys.
{% endhint %}
### Adding Amazon CloudWatch ( YAML ) data source
The first step is to create an Amazon CloudWatch data source and provide all details such as the Name, AWS Region, AWS Access Key, AWS Secret Key
* **Name:** Name of the Data Source
* **AWS Region**: Region of your AWS account
* **AWS Access Key:** access\_key\_id of your IAM Role
* **AWS Secret Key:** secret\_access\_key of your IAM Role
### Querying CloudWatch
These instructions assume you are familiar with the CloudWatch ad-hoc query language. To make exploring your data easier the schema browser will show which **Namespaces** and **Metrics ( optionally dimensions )** you can query.
### CloudWatch query designer wizard
Apica Ascent includes a simple point-and-click wizard for creating CloudWatch queries. You can launch the query wizard by selecting the CloudWatch YAML data source and selecting the "Construct CloudWatch query" icon.
CloudWatch query wizard
In the query designer, you can select the Namespace, Metric, and Dimensions along with the Stat. You can add one or more Namespaces, Metric using a simple point-and-click interface.
Add Metric
Add dimension
Edit a query manually
Select supported Stat for the query
You are now ready to run and plot the metric. Running Execute will automatically create the built-in line graph for your metric. You can further create additional visualizations using "*New Visualization*".
Running a query and plotting the time-series data
### Deep-dive into query language for CloudWatch queries
For the curious, here is a breakdown of the YAML syntax and what the various attributes mean. NOTE: You don't need to write or type these to query data. The **No-code** built-in WYSIWYG editor makes it easy to query CloudWatch without writing any code. Let us look at the YAML syntax now. It should be an array of **`MetricDataQuery`** objects under a key called **`MetricsDataQueries`**.
Here's an example that sends **`MetricDataQuery`**
```
MetricDataQueries:
- Id: q1
MetricStat:
Metric:
Namespace: AWS/Logs
MetricName: IncomingLogEvents
Dimensions:
- Name: LogGroupName
Value: flowlogs
Period: 300
Stat: Sum
StartTime: "2022-07-04 00:00:00"
```
Your query can include the following keys:
| Key | |
| ------------- | --------------------- |
| LogGroupName | string |
| LogGroupNames | array of strings |
| StartTime | integer or timestring |
| EndTime | integer or timestring |
| QueryString | string |
| Limit | integer |
### Querying AWS Lambda Metrics
Let's look at a slightly more complex example and query AWS Lambda metrics for AWS Lambda Errors. In this example, we are using the **MetricName**: *"Errors"* for the *"AWS/Lambda"* **Namespace.**
When selecting the AWS/Lambda Namespace, you can see the available MetricNames
* **AWS/Lambda**
* Errors
* ConcurrentExecutions
* Invocations
* Throttles
* Duration
* IteratorAge
* UnreservedConcurrentExecutions
Below is an example query that tracks AWS Lambda errors as an aggregate metric. The *StartTime* is templatized and allows dynamic selection.
```
MetricDataQueries:
- Id: q1
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Errors
Period: 300
Stat: Sum
StartTime: "{{StartTime}}"
```
You can further click on the *Errors* **MetricName** and it will expand to show you **Dimensions** available for further querying. For AWS/Lambda, the **Dimension** *FunctionName* provides further drill down to show Cloudwatch metrics by Lambda Function Name.
```
MetricDataQueries:
- Id: q1
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Errors
Dimensions:
- Name: FunctionName
Value:
Period: 300
Stat: Sum
StartTime: "{{StartTime}}"
```
The query can be further enhanced by making the lambda function name, a templatized parameter. This allows you to pull metrics using a dropdown selection e.g. a list of lambda functions. The FunctionName template below can also be retrieved from another database as a separate query.
```
MetricDataQueries:
- Id: q1
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Errors
Dimensions:
- Name: FunctionName
Value: {{FunctionName}}
Period: 300
Stat: Sum
StartTime: "{{StartTime}}"
```
### Examples Queries
#### Query using a single Expression
```
StartTime: 1518867432,
EndTime: 1518868432,
MetricDataQueries :
-Id: errorRate,
Label: Error Rate,
Expression: errors/requests
```
An expression can be a mathematical expression of metrics or an sql query.
#### Query using a list of expressions
```
StartTime: 1518867432
EndTime: 1518868432
MetricDataQuerie:
- Id: errorRate
Label: Error Rate
Expression: errors/requests
- Id: errorRatePercent
Label: %Error Rate
Expression: errorRate*100
```
#### Query using metric-stat or a list of metric-stats:
```
StartTime: 1518867432
EndTime: 1518868432
MetricDataQueries:
- Id: invocations
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Invocations
Period: 600
Stat: Sum
- Id: errors
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Errors
Period: 600
Stat: Sum
```
> Each list item in the MetricDataQueries list in the above mentioned examples can contain either an Expression or a MetricStat Query item. we can provide a combination of both also.
#### Query using a combination of MetricStat and Expression:
```
StartTime: 1518867432
EndTime: 1518868432
MetricDataQuerie:
- Id: errorRate
Label: Error Rate
Expression: errors*500
- Id: errors
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Errors
Period: 600
Stat: Sum
```
In the above example the second item uses MetricStat syntax to fetch data and the first item uses expression syntax to fetch the data. here, first item is used to perform a math expression on the data fetched by second item.
#### Query Example to Perform math Expression on fetched data
In the above example first and second items are used to fetch metric data. the third item is used to perform a mathematical expression on the data fetched using the first and second items.
#### Query to use Period and Stat in MetricDataQueries items
The period indicates granularity and stat indicates the group by operation to be performed on the fetched data.
```
Id: errors
MetricStat:
Metric:
Namespace: AWS/Lambda
MetricName: Invocations
Period: 600
Stat: Sum
```
or
```
Id: errors
Expression: 'some SQL query or a math expression'
period: 600
Stat: Avg
```
for some detailed information on querying cloud-watch metrics, follow the below links\
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