feat: sync posts from remote git repo

contentlayer.config.ts

@@ -1,4 +1,6 @@
-import { defineDocumentType, makeSource } from "contentlayer/source-files";
+import { spawn } from "child_process";
+import { defineDocumentType } from "contentlayer/source-files";
+import { makeSource } from "contentlayer/source-remote-files";
 
 export const Post = defineDocumentType(() => ({
   name: "Post",
@@ -9,7 +11,7 @@ export const Post = defineDocumentType(() => ({
     id: { type: "number", required: true },
     description: { type: "string", required: false },
     date: { type: "date", required: true },
-    tags: { type: "string", required: true }, //{ type: "list", of: { type: "string" }, required: true },
+    tags: { type: "string" }, //{ type: "list", of: { type: "string" }, required: true },
     seriesId: { type: "string" },
   },
   computedFields: {
@@ -20,7 +22,60 @@ export const Post = defineDocumentType(() => ({
   },
 }));
 
+const runBashCommand = (command: string) =>
+  new Promise((resolve, reject) => {
+    const child = spawn(command, [], { shell: true });
+
+    child.stdout.setEncoding("utf8");
+    child.stdout.on("data", (data) => process.stdout.write(data));
+
+    child.stderr.setEncoding("utf8");
+    child.stderr.on("data", (data) => process.stderr.write(data));
+
+    child.on("close", function (code) {
+      if (code === 0) {
+        resolve(void 0);
+      } else {
+        reject(new Error(`Command failed with exit code ${code}`));
+      }
+    });
+  });
+
+const syncContentFromGit = async (contentDir: string) => {
+  const syncRun = async () => {
+    const gitUrl = process.env.POST_REPOSITORY_URL;
+    await runBashCommand(`
+      if [ -d  "${contentDir}" ];
+        then
+          cd "${contentDir}"; git pull;
+        else
+          git clone --depth 1 --single-branch ${gitUrl} ${contentDir};
+      fi
+    `);
+  };
+
+  let wasCancelled = false;
+  let syncInterval: NodeJS.Timeout;
+
+  const syncLoop = async () => {
+    await syncRun();
+
+    if (wasCancelled) return;
+
+    syncInterval = setTimeout(syncLoop, 1000 * 60);
+  };
+
+  // Block until the first sync is done
+  await syncLoop();
+
+  return () => {
+    wasCancelled = true;
+    clearTimeout(syncInterval);
+  };
+};
+
 export default makeSource({
+  syncFiles: syncContentFromGit,
   contentDirPath: "src/posts",
   documentTypes: [Post],
 });