@codemirror/view#placeholder TypeScript Examples

ExpressionInput = ({ url, headers, value, onChange, executeQuery, readonly = false }: CMExpressionInputProps, ref) => {
  const containerRef = useRef<HTMLDivElement>(null);
  const viewRef = useRef<EditorView | null>(null);
  const executeQueryCallback = useRef(executeQuery);
  const realValue = useRef<string | undefined>(value || '');
  const defaultHeaders = {
    Authorization: `Bearer ${localStorage.getItem('access_token') || ''}`,
  };

  useEffect(() => {
    executeQueryCallback.current = executeQuery;
    promqlExtension
      .activateCompletion(true)
      .activateLinter(true)
      .setComplete({
        remote: {
          url,
          fetchFn: (resource, options = {}) => {
            const params = options.body?.toString();
            const search = params ? `?${params}` : '';
            return fetch(resource + search, {
              method: 'Get',
              headers: new Headers(
                headers
                  ? {
                      ...defaultHeaders,
                      ...headers,
                    }
                  : defaultHeaders,
              ),
            });
          },
        },
      });

    // Create or reconfigure the editor.
    const view = viewRef.current;
    if (view === null) {
      // If the editor does not exist yet, create it.
      if (!containerRef.current) {
        throw new Error('expected CodeMirror container element to exist');
      }

      const startState = EditorState.create({
        doc: value,
        extensions: [
          baseTheme,
          highlightSpecialChars(),
          history(),
          EditorState.allowMultipleSelections.of(true),
          indentOnInput(),
          bracketMatching(),
          closeBrackets(),
          autocompletion(),
          highlightSelectionMatches(),
          promqlHighlighter,
          EditorView.lineWrapping,
          keymap.of([...closeBracketsKeymap, ...defaultKeymap, ...historyKeymap, ...commentKeymap, ...completionKeymap, ...lintKeymap]),
          placeholder('Expression (press Shift+Enter for newlines)'),
          promqlExtension.asExtension(),
          EditorView.editable.of(!readonly),
          keymap.of([
            {
              key: 'Escape',
              run: (v: EditorView): boolean => {
                v.contentDOM.blur();
                return false;
              },
            },
          ]),
          Prec.override(
            keymap.of([
              {
                key: 'Enter',
                run: (v: EditorView): boolean => {
                  if (typeof executeQueryCallback.current === 'function') {
                    executeQueryCallback.current(realValue.current);
                  }
                  return true;
                },
              },
              {
                key: 'Shift-Enter',
                run: insertNewlineAndIndent,
              },
            ]),
          ),
          EditorView.updateListener.of((update: ViewUpdate): void => {
            if (typeof onChange === 'function') {
              const val = update.state.doc.toString();
              if (val !== realValue.current) {
                realValue.current = val;
                onChange(val);
              }
            }
          }),
        ],
      });

      const view = new EditorView({
        state: startState,
        parent: containerRef.current,
      });

      viewRef.current = view;

      if (ref) {
        ref.current = view;
      }

      view.focus();
    }
  }, [onChange, JSON.stringify(headers)]);

  useEffect(() => {
    if (realValue.current !== value) {
      const oldValue = realValue.current;
      realValue.current = value || '';
      const view = viewRef.current;
      if (view === null) {
        return;
      }
      view.dispatch(
        view.state.update({
          changes: { from: 0, to: oldValue?.length || 0, insert: value },
        }),
      );
    }
  }, [value]);

  return (
    <div
      className={classNames({ 'ant-input': true, readonly: readonly, 'promql-input': true })}
      onBlur={() => {
        if (typeof onChange === 'function') {
          onChange(realValue.current);
        }
      }}
    >
      <div className='input-content' ref={containerRef} />
    </div>
  );
}

ExpressionInput: FC<CMExpressionInputProps> = ({ value, onExpressionChange, queryHistory, metricNames, isLoading, executeQuery }) => {
  const containerRef = useRef<HTMLDivElement>(null);
  const viewRef = useRef<EditorView | null>(null);
  const executeQueryCallback = useRef(executeQuery);
  const [showMetricsExplorer, setShowMetricsExplorer] = useState<boolean>(false);

  useEffect(() => {
    executeQueryCallback.current = executeQuery;
    promqlExtension
      .activateCompletion(true)
      .activateLinter(true)
      .setComplete({
        remote: { url, fetchFn: myHTTPClient, cache: { initialMetricList: metricNames } },
      });

    // Create or reconfigure the editor.
    const view = viewRef.current;
    if (view === null) {
      // If the editor does not exist yet, create it.
      if (!containerRef.current) {
        throw new Error('expected CodeMirror container element to exist');
      }

      const startState = EditorState.create({
        doc: value,
        extensions: [
          baseTheme,
          highlightSpecialChars(),
          history(),
          EditorState.allowMultipleSelections.of(true),
          indentOnInput(),
          bracketMatching(),
          closeBrackets(),
          autocompletion(),
          highlightSelectionMatches(),
          promqlHighlighter,
          EditorView.lineWrapping,
          keymap.of([...closeBracketsKeymap, ...defaultKeymap, ...historyKeymap, ...commentKeymap, ...completionKeymap, ...lintKeymap]),
          placeholder('Expression (press Shift+Enter for newlines)'),
          promqlExtension.asExtension(),
          // This keymap is added without precedence so that closing the autocomplete dropdown
          // via Escape works without blurring the editor.
          keymap.of([
            {
              key: 'Escape',
              run: (v: EditorView): boolean => {
                v.contentDOM.blur();
                return false;
              },
            },
          ]),
          Prec.override(
            keymap.of([
              {
                key: 'Enter',
                run: (v: EditorView): boolean => {
                  executeQueryCallback.current();
                  return true;
                },
              },
              {
                key: 'Shift-Enter',
                run: insertNewlineAndIndent,
              },
            ]),
          ),
          EditorView.updateListener.of((update: ViewUpdate): void => {
            onExpressionChange(update.state.doc.toString());
          }),
        ],
      });

      const view = new EditorView({
        state: startState,
        parent: containerRef.current,
      });

      viewRef.current = view;

      view.focus();
    }
  }, [executeQuery, onExpressionChange, queryHistory]);

  const insertAtCursor = (value: string) => {
    const view = viewRef.current;
    if (view === null) {
      return;
    }
    const { from, to } = view.state.selection.ranges[0];
    view.dispatch(
      view.state.update({
        changes: { from, to, insert: value },
      }),
    );
  };

  return (
    <>
      <div className='prometheus-input-box'>
        <div className='input-prefix'>
          <span>PromQL: </span>
        </div>
        <div className='input'>
          <div className='input-content' ref={containerRef} />
        </div>
        <div className='suffix'>
          <Button size='large' className='metrics' icon={<GlobalOutlined />} onClick={() => setShowMetricsExplorer(true)}></Button>
          <Button size='large' type='primary' className='execute' onClick={executeQuery}>
            Execute
          </Button>
        </div>
      </div>

      {/* 点击按钮的弹出Modal */}
      <MetricsExplorer show={showMetricsExplorer} updateShow={setShowMetricsExplorer} metrics={metricNames} insertAtCursor={insertAtCursor} />
    </>
  );
}