docs for URI and CODE

docs/Catalog/URI.md

@@ -0,0 +1,59 @@
+<!-- markdownlint-disable-next-line first-line-h1 -->
+Every package and object in the Bucket and Packages views has a "CODE" pane,
+which contains code snippets that can be used to download and upload a package
+or object via either:
+
+- Python (API) ![Python](../imgs/uri-python.png)
+- CLI (shell commands) ![CLI](../imgs/uri-cli.png)
+
+In addition, Packages have a third tab that returns a Quilt+ URI:
+
+- URI (identifier) ![URI](../imgs/uri-uri.png)
+
+They all have a `copy` button that copies the code to the clipboard.
+
+## Quilt+ URIs
+
+Quilt+ URIs are a way to uniquely identify a package or object in the Quilt
+catalog. They are used to reference packages and objects relative to a Quilt
+bucket.  For example:
+
+<!-- markdownlint-disable-next-line line-length -->
+`quilt+s3://quilt-example#package=akarve/cord19@e21682f00929661879633a5128aaa27cc7bc1e2973d49d4c868a90f9fad9f34b&path=CORD19.ipynb`
+
+The URI above references a specific version of the `CORD19.ipynb` notebook in
+the `akarve/cord19` package of the `quilt-example` bucket.
+
+### Catalog Usage
+
+URIs can be used to quickly navigate to a specific package or object from the
+Catalog.  If your window is wide enough, there will be a "URI" button to the
+right of the search bar.  Clicking this button will display a dialog where you
+can paste a URI and "Resolve" it to navigate to the package or object it
+references.
+
+![Resolving URIs](../imgs/uri-resolve.png)
+
+### Syntax
+
+A Quilt+ URI most contain the following components:
+
+- `quilt+`: The scheme of the URI. This is always `quilt+`.
+- `s3://`: The protocol of the URI. This is currently `s3://`.
+- `<bucket>`: The name of the bucket containing the package or object, e.g.
+  `quilt-example`.
+- `#package=<package>`: A fragment for the name of the package containing the
+  object, e.g. `akarve/cord19`.
+
+In addition, it may contain the following optional components:
+
+- `<package>@<top_hash>`: The hash for this specific package, e.g.
+  `e21682f00929661879633a5128aaa27cc7bc1e2973d49d4c868a90f9fad9f34b`.
+- `<package>:tag`: The tag for this specific package. Currently, only the
+  `latest` tag is supported.  You may not specify both a top_hash and a tag.
+- `&path=<path>`: Fragment for the path to the object within the package, if
+  any, e.g.ß `CORD19.ipynb`.
+  was located.
+
+Note that a given bucket may be available from zero or more catalogs,
+each of which may support different users and access controls.

docs/SUMMARY.md

@@ -13,6 +13,7 @@
 * [Document Previews](Catalog/Preview.md)
 * [Embeddable iFrames](Catalog/Embed.md)
 * [Search & Query](Catalog/SearchQuery.md)
+* [Quilt+ URIs](Catalog/URI.md)
 * [Qurator Omni](Catalog/Qurator.md) AI Assistant
 * [Visualization & Dashboards](Catalog/VisualizationDashboards.md)
 * **Advanced**