Add a multi-value input component (#47804)

* Add Kubernetes access section to the role editor

* Add a multi-value input component

* Review

* Update the k8s operator docs

This also removes the mention of valid values of the Kind field, as I don't
want the external documentation to point to Teleport source files.

* Update operator CRDs and Terraform resources

* Lint, licenses

web/packages/shared/components/FieldMultiInput/FieldMultiInput.story.tsx

@@ -0,0 +1,37 @@
+/**
+ * Teleport
+ * Copyright (C) 2024 Gravitational, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import React, { useState } from 'react';
+
+import Box from 'design/Box';
+
+import { FieldMultiInput } from './FieldMultiInput';
+
+export default {
+  title: 'Shared',
+};
+
+export function Story() {
+  const [items, setItems] = useState([]);
+  return (
+    <Box width="500px">
+      <FieldMultiInput label="Some items" value={items} onChange={setItems} />
+    </Box>
+  );
+}
+Story.storyName = 'FieldMultiInput';

web/packages/shared/components/FieldMultiInput/FieldMultiInput.test.tsx

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+/**
+ * Teleport
+ * Copyright (C) 2024 Gravitational, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import userEvent from '@testing-library/user-event';
+import React, { useState } from 'react';
+
+import { render, screen } from 'design/utils/testing';
+
+import { FieldMultiInput, FieldMultiInputProps } from './FieldMultiInput';
+
+const TestFieldMultiInput = ({
+  onChange,
+  ...rest
+}: Partial<FieldMultiInputProps>) => {
+  const [items, setItems] = useState<string[]>([]);
+  const handleChange = (it: string[]) => {
+    setItems(it);
+    onChange?.(it);
+  };
+  return <FieldMultiInput value={items} onChange={handleChange} {...rest} />;
+};
+
+test('adding, editing, and removing items', async () => {
+  const user = userEvent.setup();
+  const onChange = jest.fn();
+  render(<TestFieldMultiInput onChange={onChange} />);
+
+  await user.type(screen.getByRole('textbox'), 'apples');
+  expect(onChange).toHaveBeenLastCalledWith(['apples']);
+
+  await user.click(screen.getByRole('button', { name: 'Add More' }));
+  expect(onChange).toHaveBeenLastCalledWith(['apples', '']);
+
+  await user.type(screen.getAllByRole('textbox')[1], 'oranges');
+  expect(onChange).toHaveBeenLastCalledWith(['apples', 'oranges']);
+
+  await user.click(screen.getAllByRole('button', { name: 'Remove Item' })[0]);
+  expect(onChange).toHaveBeenLastCalledWith(['oranges']);
+
+  await user.click(screen.getAllByRole('button', { name: 'Remove Item' })[0]);
+  expect(onChange).toHaveBeenLastCalledWith([]);
+});
+
+test('keyboard handling', async () => {
+  const user = userEvent.setup();
+  const onChange = jest.fn();
+  render(<TestFieldMultiInput onChange={onChange} />);
+
+  await user.click(screen.getByRole('textbox'));
+  await user.keyboard('apples{Enter}oranges');
+  expect(onChange).toHaveBeenLastCalledWith(['apples', 'oranges']);
+
+  await user.click(screen.getAllByRole('textbox')[0]);
+  await user.keyboard('{Enter}bananas');
+  expect(onChange).toHaveBeenLastCalledWith(['apples', 'bananas', 'oranges']);
+});

web/packages/shared/components/FieldMultiInput/FieldMultiInput.tsx

@@ -0,0 +1,139 @@
+/**
+ * Teleport
+ * Copyright (C) 2024 Gravitational, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import Box from 'design/Box';
+import { ButtonSecondary } from 'design/Button';
+import ButtonIcon from 'design/ButtonIcon';
+import Flex from 'design/Flex';
+import * as Icon from 'design/Icon';
+import Input from 'design/Input';
+import { useRef } from 'react';
+import styled, { useTheme } from 'styled-components';
+
+export type FieldMultiInputProps = {
+  label?: string;
+  value: string[];
+  disabled?: boolean;
+  onChange?(val: string[]): void;
+};
+
+/**
+ * Allows editing a list of strings, one value per row. Use instead of
+ * `FieldSelectCreatable` when:
+ *
+ * - There are no predefined values to be picked from.
+ * - Values are expected to be relatively long and would be unreadable after
+ *   being truncated.
+ */
+export function FieldMultiInput({
+  label,
+  value,
+  disabled,
+  onChange,
+}: FieldMultiInputProps) {
+  if (value.length === 0) {
+    value = [''];
+  }
+
+  const theme = useTheme();
+  // Index of the input to be focused after the next rendering.
+  const toFocus = useRef<number | undefined>();
+
+  const setFocus = element => {
+    element?.focus();
+    toFocus.current = undefined;
+  };
+
+  function insertItem(index: number) {
+    onChange?.(value.toSpliced(index, 0, ''));
+  }
+
+  function removeItem(index: number) {
+    onChange?.(value.toSpliced(index, 1));
+  }
+
+  function handleKeyDown(index: number, e: React.KeyboardEvent) {
+    if (e.key === 'Enter') {
+      insertItem(index + 1);
+      toFocus.current = index + 1;
+    }
+  }
+
+  return (
+    <Box>
+      <Fieldset>
+        {label && <Legend>{label}</Legend>}
+        {value.map((val, i) => (
+          // Note on keys: using index as a key is an anti-pattern in general,
+          // but here, we can safely assume that even though the list is
+          // editable, we don't rely on any unmanaged HTML element state other
+          // than focus, which we deal with separately anyway. The alternatives
+          // would be either to require an array with keys generated
+          // synthetically and injected from outside (which would make the API
+          // difficult to use) or to keep the array with generated IDs as local
+          // state (which would require us to write a prop/state reconciliation
+          // procedure whose complexity would probably outweigh the benefits).
+          <Flex key={i} alignItems="center" gap={2}>
+            <Box flex="1">
+              <Input
+                value={val}
+                ref={toFocus.current === i ? setFocus : null}
+                onChange={e =>
+                  onChange?.(
+                    value.map((v, j) => (j === i ? e.target.value : v))
+                  )
+                }
+                onKeyDown={e => handleKeyDown(i, e)}
+              />
+            </Box>
+            <ButtonIcon
+              size="0"
+              title="Remove Item"
+              onClick={() => removeItem(i)}
+              disabled={disabled}
+            >
+              <Icon.Cross size="small" color={theme.colors.text.muted} />
+            </ButtonIcon>
+          </Flex>
+        ))}
+        <ButtonSecondary
+          alignSelf="start"
+          onClick={() => insertItem(value.length)}
+        >
+          <Icon.Plus size="small" mr={2} />
+          Add More
+        </ButtonSecondary>
+      </Fieldset>
+    </Box>
+  );
+}
+
+const Fieldset = styled.fieldset`
+  border: none;
+  margin: 0;
+  padding: 0;
+  display: flex;
+  flex-direction: column;
+  gap: ${props => props.theme.space[2]}px;
+`;
+
+const Legend = styled.legend`
+  margin: 0 0 ${props => props.theme.space[1]}px 0;
+  padding: 0;
+  ${props => props.theme.typography.body3}
+`;