1 files changed, 54 insertions, 0 deletions
diff --git a/src/metadata.ts b/src/metadata.ts
new file mode 100644
index 0000000..1eb7f1a
--- /dev/null
+++ b/src/metadata.ts
@@ -0,0 +1,54 @@
+import { Db } from "mongodb";
+
+/** //FIXME fix document schema
+ * Rather than using branches as the core, this should be adopted into the following document model:
+ * repo:
+ *  - org
+ *  - name
+ *  - token
+ *  - branches: {
+ *      [branchname]: {
+ *        head
+ *      }
+ *    }
+ */
+export interface Branch {
+  org: string;
+  repo: string;
+  name: string;
+  head: string;
+}
+
+class Metadata {
+  database: Db;
+
+  constructor(client: Db) {
+    this.database = client;
+  }
+
+  async getHeadCommit(
+    org: string,
+    repo: string,
+    branch: string
+  ): Promise<string> {
+    const result = await this.database
+      .collection<Branch>("branch")
+      .findOne({ org, repo, name: branch });
+
+    if (result !== null) {
+      return result.head;
+    } else {
+      throw Error("Branch not found");
+    }
+  }
+
+  async updateBranch(branch: Branch): Promise<boolean> {
+    const { head, ...matcher } = branch;
+    const { result } = await this.database
+      .collection<Branch>("branch")
+      .replaceOne(matcher, branch, { upsert: true });
+    return result.ok === 1;
+  }
+}
+
+export default Metadata;