feat: #30 Allow for variable-width columns and more than two columns

package.json

@@ -47,6 +47,7 @@
   "//file-type": "have to use this version before they switched to ESM, which gives a compile error related to require()",
   "//node-fetch@2.6.6file-type": "have to use this version before they switched to ESM, which gives a compile error related to require()",
   "//chalk@4": "also ESM related problem",
+  "//notion-client@4": "also ESM related problem",
   "dependencies": {
     "@notionhq/client": "^1.0.4",
     "chalk": "^4.1.2",
@@ -56,15 +57,16 @@
     "limiter": "^2.1.0",
     "markdown-table": "^2.0.0",
     "node-fetch": "2.6.6",
+    "notion-client": "^4",
     "notion-to-md": "^2.5.5",
     "path": "^0.12.7",
     "postinstall-postinstall": "^2.1.0",
     "sanitize-filename": "^1.6.3"
   },
   "devDependencies": {
-    "@types/markdown-table": "^2.0.0",
     "@types/fs-extra": "^9.0.13",
     "@types/jest": "^28.1.6",
+    "@types/markdown-table": "^2.0.0",
     "@types/node": "^12.20.11",
     "@typescript-eslint/eslint-plugin": "^4.22.0",
     "@typescript-eslint/parser": "^4.22.0",

src/css/notion-styles.css

@@ -1,6 +1,12 @@
-/* some things copied from https://github1s.com/NotionX/react-notion-x/blob/master/packages/react-notion-x/src/styles.css#L934 */
-/* note, I haven't figure out how a Docusaurus app can actually include this, yet */
+/* Note, I haven't figure out how a Docusaurus app can actually include this, yet.
+  So currently this has to be duplicated by the client.
+*/
 
+/* Copied from
+    https://github1s.com/NotionX/react-notion-x/blob/master/packages/react-notion-x/src/styles.css#L934
+    and
+    https://github1s.com/NotionX/react-notion-x/blob/master/packages/react-notion-x/src/styles.css#L1063
+*/
 .notion-column {
   display: flex;
   flex-direction: column;
@@ -21,17 +27,10 @@
 }
 
 .notion-row {
-  display: grid;
-  grid-auto-flow: column;
-  /* at the moment, docu-notion doesn't give us column widths or ratios. So we
-  could let css layout decide the widths. Instead at the moment we're saying
-  let's just have each column be equal. This is easier for the author using
-  Notion to remember than having to guess at what the layout will be. */
-  grid-auto-columns: 1fr;
+  display: flex;
   overflow: hidden;
   width: 100%;
   max-width: 100%;
-  gap: 30px;
 }
 
 @media (max-width: 640px) {
@@ -47,3 +46,13 @@
     display: none;
   }
 }
+
+.notion-spacer {
+  /* This matches the value in ColumnTransformer.ts */
+  width: calc(min(32px, 4vw));
+}
+
+.notion-spacer:last-child {
+  display: none;
+}
+/* End copied from NotionX */

src/transformers/ColumnTransformer.ts

@@ -1,4 +1,5 @@
 import { Client } from "@notionhq/client";
+import { NotionAPI } from "notion-client";
 import { NotionToMarkdown } from "notion-to-md";
 import { ListBlockChildrenResponseResult } from "notion-to-md/build/types";
 import { getBlockChildren } from "./CustomTransformers";
@@ -21,9 +22,45 @@ export async function notionColumnToMarkdown(
 
   const childrenStrings: string[] = await Promise.all(childrenPromise);
 
+  const columnWidth = await getColumnWidth(block);
+
   // note: it would look better in the markup with \n, but that
   // causes notion-to-md to give us ":::A" instead of \n for some reason.
-  return `<div class='notion-column'>\n\n${childrenStrings.join(
-    "\n\n"
-  )}\n\n</div>`;
+  return (
+    `<div class='notion-column' style={{width: '${columnWidth}'}}>\n\n${childrenStrings.join(
+      "\n\n"
+    )}\n\n</div>` +
+    // Spacer between columns. CSS takes care of hiding this for the last column
+    // and when the screen is too narrow for multiple columns.
+    `<div className='notion-spacer' />`
+  );
+}
+
+// The official API doesn't give us access to the format information, including column_ratio.
+// So we use 'notion-client' which uses the unofficial API.
+// Once the official API gives us access to the format information, we can remove this
+// and the 'notion-client' dependency.
+// This logic was mostly taken from react-notion-x (sister project of notion-client).
+async function getColumnWidth(
+  block: ListBlockChildrenResponseResult
+): Promise<string> {
+  const notion = new NotionAPI();
+  const blockId = block.id;
+  // Yes, it is odd to call 'getPage' for a block, but that's how we access the format info.
+  const recordMap = await notion.getPage(blockId);
+  const blockResult = recordMap.block[blockId];
+
+  const columnFormat = blockResult?.value?.format as any;
+  const columnRatio = (columnFormat?.column_ratio as number) || 0.5;
+
+  const parentBlock = recordMap.block[blockResult?.value?.parent_id]?.value;
+  // I'm not sure why we wouldn't get a parent, but the react-notion-x has
+  // this fallback to a guess based on the columnRatio.
+  const columnCount =
+    parentBlock?.content?.length || Math.max(2, Math.ceil(1.0 / columnRatio));
+
+  const spacerWidth = `min(32px, 4vw)`; // This matches the value in css for 'notion-spacer'.
+  return `calc((100% - (${spacerWidth} * ${
+    columnCount - 1
+  })) * ${columnRatio})`;
 }