fix(store-s3): check if file exists before creating

paulrobertlloyd · paulrobertlloyd · commit e1468c42955c · 2024-10-08T20:54:46.000+01:00
diff --git a/packages/store-s3/index.js b/packages/store-s3/index.js
@@ -61,6 +61,26 @@ export default class S3Store {
     return client;
   }
 
+  /**
+   * Check if file exists
+   * @param {string} filePath - Path to file
+   * @returns {Promise<boolean>} File exists
+   */
+  async fileExists(filePath) {
+    try {
+      const getCommand = new GetObjectCommand({
+        Bucket: this.options.bucket,
+        Key: filePath,
+      });
+
+      await this.client().send(getCommand);
+
+      return true;
+    } catch {
+      return false;
+    }
+  }
+
   /**
    * Create file
    * @param {string} filePath - Path to file
@@ -75,6 +95,11 @@ export default class S3Store {
     });
 
     try {
+      const fileExists = await this.fileExists(filePath);
+      if (fileExists) {
+        return;
+      }
+
       const { ETag } = await this.client().send(putCommand);
 
       if (ETag) {
diff --git a/packages/store-s3/test/index.js b/packages/store-s3/test/index.js
@@ -42,7 +42,16 @@ describe("store-s3", () => {
     assert.equal(indiekit.publication.store.info.name, "website bucket");
   });
 
+  it("Checks if file exists", async () => {
+    mockS3Client.on(GetObjectCommand).resolves({ ETag: "true" });
+    assert.equal(await s3.fileExists("foo.md"), true);
+
+    mockS3Client.on(GetObjectCommand).rejects("Couldn’t get object");
+    assert.equal(await s3.fileExists("foo.md"), false);
+  });
+
   it("Creates file", async () => {
+    mockS3Client.on(GetObjectCommand).rejects("Couldn’t get object");
     mockS3Client.on(PutObjectCommand).resolves({ ETag: "true" });
 
     assert.equal(
@@ -51,7 +60,14 @@ describe("store-s3", () => {
     );
   });
 
+  it("Doesn’t create file if already exists", async () => {
+    mockS3Client.on(GetObjectCommand).resolves({ ETag: "true" });
+
+    assert.equal(await s3.createFile("foo.md", "foobar"), undefined);
+  });
+
   it("Throws error creating file", async () => {
+    mockS3Client.on(GetObjectCommand).rejects("Couldn’t get object");
     mockS3Client.on(PutObjectCommand).rejects("Couldn’t put object");
 
     await assert.rejects(s3.createFile("foo.md", ""), {
