2 Queries in Syntax-Extended JavaScript syntax

This chapter contains a cookbook of example queries using the CarbonQL client libraries.

Each example is provided in both TypeScript and an experimental JavaScript client. This JavaScript client uses the Babel JavaScript compiler's plugin API to embed SQL-like keywords into the JavaScript language, making it easier for non-programmers to write queries against the CarbonQL API.

For example, below we have a query that will retrieve and print all versions of the mysql container running in the cluster. Notice that the query is freely intermingled with JavaScript source, which is possible because we've extended the language to support it. (Copied from an example in the "governance" section.)

import {Client, query} from "carbonql";

const c = Client.fromFile(<string>process.env.KUBECONFIG);
const mySqlVersions =
  from pod in c.core.v1.Pod.list("default")
  from container in pod.spec.containers
  // Filter image names that don't include "mysql", return distinct.
  where container.image.includes("mysql")
  // Return just the container image.
  select container.image;

mySqlVersions.distinct().forEach(console.log);

import {Client, query} from "carbonql";

const c = Client.fromFile(<string>process.env.KUBECONFIG);
const mySqlVersions = c.core.v1.Pod
  .list("default")
  // Obtain all container image names running in all pods.
  .flatMap(pod => pod.spec.containers)
  .map(container => container.image)
  // Filter image names that don't include "mysql", return distinct.
  .filter(imageName => imageName.includes("mysql"))
  .distinct();

// Prints the distinct container image tags.
mySqlVersions.forEach(console.log);

Because we are still working on the exact syntax and semantics, the experimental JavaScript is not yet available. It will be if we get positive feedback.

The chapter is broken up into two sections, each with a different motivating use case:

• Governance Queries, which are motivated by the need of engineering and IT leadership to understand what is happening in their organizations, and how they are tracking against important metrics relating to, e.g., applied security updates, compliance, network security, and so on.
• Operations Queries, which are motivated by the need of engineers to understand what is happening inside their cluster to, e.g., mitigate livesite incidents, detect misconfigurations during a rollout, and so on.