Query Your Infrastructure

Learn to run MQL queries from the command line and include MQL queries in automation.

MQL is a lightweight, fast query language built for searching and filtering infrastructure configuration data. Its data extraction resembles GraphQL, while its scripting approach is similar to JavaScript.

MQL integrates with hundreds of resources to retrieve information about your infrastructure.

Run standalone queries from the command line

The interactive cnquery shell, with auto-complete, is the easiest way to query your systems. Learn more.

To run standalone queries from the command line, use the cnquery run command:

cnquery run TARGET -c QUERY

For...	Substitute...
`TARGET`	The asset to query, such as `local` or a transport to a remote machine.
`QUERY`	The MQL query that specifies the information you want.

Examples

List services and their running status on your local system:

cnquery run local -c "services.list { name running }"

Find all AWS EC2 instances with a public IP address:

aws.ec2.instances.where( publicIp != '' ) {
  instanceId
  region
  state
  tags
  publicIp
}

List all users with every available field:

users.list { * }

Find all container image repositories used in a Kubernetes cluster:

k8s.pods {
 name
 containers.map( containerImage.repository.fullName )
}

.map is a function for arrays that takes a given field and extracts it. Unlike block calls ({ .. }), it directly returns the given field.

Resources and fields

Resources are the building blocks for writing queries. They let you retrieve the configuration of an asset. Some examples:

asset — Information about the asset, including name, family, release, and more
user — User information, including name, UID, GID, home, shell, and more
packages — Package information, including name, version, installed, outdated, and more
k8s.container — Kubernetes container configuration, including imagePullPolicy, workingDir, and more
terraform.block — Terraform block arguments, attributes, and more

Each resource has fields that return specific configuration values. Retrieve multiple fields at once using braces:

asset { platform version arch }

For a full list of available resources, enter the help command within the cnquery shell, or browse the MQL resource reference.

Operators and functions

For information on MQL operators and functions, read Write Effective MQL.

Learn more

To explore cnquery commands, read the CLI Reference.
To explore the capabilities of the MQL language, read the MQL docs.