druid/web-console/README.md

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# Apache Druid web console

This is the unified Druid web console that servers as a data management layer for Druid.

## How to watch and run for development

1. You need to be within the `web-console` directory
2. Install the modules with `npm install`
3. Run `npm run compile` to compile the scss files
4. Run `npm start` will start in development mode and will proxy druid requests to `localhost:8888`


**Note:** you can provide an environment variable to proxy to a different Druid host like so: `druid_host=1.2.3.4:8888 npm start`
**Note:** you can provide an environment variable use webpack-bundle-analyzer as a plugin in the build script or like so: `BUNDLE_ANALYZER_PLUGIN='TRUE' npm start`

To try the console in (say) coordinator mode you could run it as such:

`druid_host=localhost:8081 npm start`

## Description of the directory structure

A lot of the directory structure was created to preserve the existing console structure as much as possible.

As part of this repo:

- `assets/` - The images (and other assets) used within the console
- `e2e-tests/` - End-to-end tests for the console
- `lib/` - A place where some overrides to the react-table stylus files live, this is outside of the normal SCSS build system.
- `public/` - The compiled destination of the file powering this console
- `script/` - Some helper bash scripts for running this console
- `src/` - This directory (together with `lib`) constitutes all the source code for this console

## List of non SQL data reading APIs used

```
GET /status
GET /druid/indexer/v1/supervisor?full
POST /druid/indexer/v1/worker
GET /druid/indexer/v1/workers
GET /druid/indexer/v1/tasks
GET /druid/coordinator/v1/loadqueue?simple
GET /druid/coordinator/v1/config
GET /druid/coordinator/v1/metadata/datasources?includeUnused
GET /druid/coordinator/v1/rules
GET /druid/coordinator/v1/config/compaction
GET /druid/coordinator/v1/tiers
```

## Updating the list of license files

From the web-console directory run `script/licenses`

## Running End-to-End Tests

From the web-console directory:

1. Build druid distribution: `script/druid build`
2. Start druid cluster: `script/druid start`
3. Run end-to-end tests: `npm run test-e2e`
4. Stop druid cluster: `script/druid stop`

If you already have a druid cluster running on the standard ports, the steps to build/start/stop a druid cluster can
be skipped.

### Debugging

#### Screenshots

`e2e-tests/util/debug.ts:saveScreenshotIfError()` is used to save a screenshot of the web console
when the test fails. For example, if `e2e-tests/tutorial-batch.spec.ts` fails, it will create
`load-data-from-local-disk-error-screenshot.png`.

#### Disabling Headless Mode

Disabling headless mode while running the tests can be helpful. This can be done via the `DRUID_E2E_TEST_HEADLESS`
environment variable, which defaults to `true`.

#### Running Against Alternate Web Console

The environment variable `DRUID_E2E_TEST_UNIFIED_CONSOLE_PORT` can be used to target a web console running on a
non-default port (i.e., not port `8888`). For example, this environment variable can be used to target the
development mode of the web console (started via `npm start`), which runs on port `18081`.