Update docs

Signed-off-by: Kim, Vinnam <[email protected]>

docs/source/docs/command-reference/helper/format.md

@@ -0,0 +1,20 @@
+# Format
+
+This command shows a list of supported import/export data formats in Datumaro.
+It is useful on a quick reference of data format name used for other CLI command such as [convert](../context_free/convert.md), [import](../context/sources.md#import-dataset), or [export](../context/export.md#export-datasets). For more detailed guides on each data format, please visit [our Data Formats section](../../data-formats).
+
+Usage:
+
+```console
+usage: datum format [-h] [-li | -le] [-d DELIMITER]
+```
+
+Parameters:
+- `-h, --help` - Print the help message and exit.
+- `-d DELIMITER, --delimiter DELIMITER` - Seperator used to list data format names (default: `\n`). For example, `datum format -d ','` command displays
+  ```console
+  Supported import formats:
+  ade20k2017,ade20k2020,align_celeba,...
+  ```
+- `-li, --list-import` - List all supported import data format names
+- `-le, --list-export` - List all supported export data format names

docs/source/docs/command-reference/helper/index.rst

@@ -0,0 +1,9 @@
+===============
+Helper Commands
+===============
+
+.. toctree::
+    :maxdepth: 1
+    :glob:
+
+    *

docs/source/docs/command-reference/overview.rst

@@ -2,8 +2,8 @@
 Overview
 ========
 
-The command line is split into the separate ``commands`` (:ref:`Context Commands`)
-and command ``contexts`` (:ref:`Context-free Commands`).
+The command line is split into three groups:
+``commands`` (:ref:`Context Commands`), command ``contexts`` (:ref:`Context-free Commands`), and ``helpers`` (:ref:`Helper Commands`).
 Contexts group multiple commands related to a specific topic, e.g.
 project operations, data source operations etc. Almost all the commands
 operate on projects, so the ``project`` context and commands without a context

docs/source/docs/explanation/command_line.dot

@@ -32,6 +32,11 @@ digraph command_line {
         "util";
     }
 
+    subgraph helper {
+        label = "Helper";
+        "format";
+    }
+
     subgraph cluster_model {
         label = "Model";
         "madd" [label = "add";];
@@ -70,7 +75,7 @@ digraph command_line {
         "split_video";
     }
 
-    "datum" -> {"convert" "detect" "compare" "dinfo" "download" "explain" "filter" "generate" "merge" "patch" "search" "stats" "transform" "validate"};
+    "datum" -> {"convert" "detect" "compare" "dinfo" "download" "explain" "filter" "generate" "merge" "patch" "search" "stats" "transform" "validate" "format"};
     "datum" -> {"model" "project" "source" "util"};
     "model" -> {"madd" "mremove" "run" "minfo"};
     "project" -> {"add" "create" "export" "import" "remove"};