# Discovery and mappings

> Find the resources in each account and map each source to its destination.

## Discovery

Douklar keeps cached catalogs of **S3 buckets** and **ECR repositories** per
account, under Resources. Refresh them explicitly with **Refresh AWS**; **Load cached** reuses the last list. Caches
of signed-out accounts are withheld.

## Mappings

A **mapping** is one source to destination pair for one service:

- ECR: a repository and tags.
- S3: a bucket (optionally with a prefix group).
- CodeCommit: a repository.
- DynamoDB: a table.

Destinations may have a different name than the source. Mappings are grouped
by **app**, so one run can select a whole application's resources.

![Mapping studio with a table of ECR mappings from source to destination repositories](console:map)

One run can **fan out** from one source to several destination accounts.

## Where mappings live

Mappings are edited in the console's Mapping studio or in
`config/simple-config.ini`. The runtime file `config/sync.yaml` is generated
from it; edit the INI file, not `sync.yaml`. Unsaved edits are autosaved, and each browser
tab keeps its own working copy.

These files hold no AWS secret keys; credentials stay in the profiles.

With the CLI:

```bash
douklar config validate --config config/simple-config.ini
douklar config generate --config config/simple-config.ini --format yaml --output config/sync.yaml
```

## Moving config from the CLI to the console

Configuration moves one way, from CLI to console, as an exported bundle. The
console previews the bundle and applies it only when you confirm. Bundles can
be signed with Ed25519; unsigned bundles are accepted with a warning unless
the console requires signatures.

Source: https://douklar.app/docs/douklar/discovery-and-mappings (Douklar docs, last checked 2026-10-23)