techdocs: Add etag as techdocs metadata type

Signed-off-by: Himanshu Mishra <himanshu@orkohunter.net>

packages/techdocs-common/src/stages/publish/awsS3.test.ts

@@ -192,13 +192,14 @@ describe('AwsS3Publish', () => {
       mockFs({
         [entityRootDir]: {
           'techdocs_metadata.json':
-            '{"site_name": "backstage", "site_description": "site_content"}',
+            '{"site_name": "backstage", "site_description": "site_content", "etag": "etag"}',
         },
       });
 
       const expectedMetadata: TechDocsMetadata = {
         site_name: 'backstage',
         site_description: 'site_content',
+        etag: 'etag',
       };
       expect(
         await publisher.fetchTechDocsMetadata(entityNameMock),
@@ -213,13 +214,14 @@ describe('AwsS3Publish', () => {
 
       mockFs({
         [entityRootDir]: {
-          'techdocs_metadata.json': `{'site_name': 'backstage', 'site_description': 'site_content'}`,
+          'techdocs_metadata.json': `{'site_name': 'backstage', 'site_description': 'site_content', 'etag': 'etag'}`,
         },
       });
 
       const expectedMetadata: TechDocsMetadata = {
         site_name: 'backstage',
         site_description: 'site_content',
+        etag: 'etag',
       };
       expect(
         await publisher.fetchTechDocsMetadata(entityNameMock),

packages/techdocs-common/src/stages/publish/googleStorage.test.ts

@@ -193,13 +193,14 @@ describe('GoogleGCSPublish', () => {
       mockFs({
         [entityRootDir]: {
           'techdocs_metadata.json':
-            '{"site_name": "backstage", "site_description": "site_content"}',
+            '{"site_name": "backstage", "site_description": "site_content", "etag": "etag"}',
         },
       });
 
       const expectedMetadata: TechDocsMetadata = {
         site_name: 'backstage',
         site_description: 'site_content',
+        etag: 'etag',
       };
       expect(
         await publisher.fetchTechDocsMetadata(entityNameMock),
@@ -214,13 +215,14 @@ describe('GoogleGCSPublish', () => {
       mockFs({
         [entityRootDir]: {
           'techdocs_metadata.json':
-            "{'site_name': 'backstage', 'site_description': 'site_content'}",
+            "{'site_name': 'backstage', 'site_description': 'site_content', 'etag': 'etag'}",
         },
       });
 
       const expectedMetadata: TechDocsMetadata = {
         site_name: 'backstage',
         site_description: 'site_content',
+        etag: 'etag',
       };
       expect(
         await publisher.fetchTechDocsMetadata(entityNameMock),

packages/techdocs-common/src/stages/publish/types.ts

@@ -43,6 +43,7 @@ export type PublishResponse = {
 export type TechDocsMetadata = {
   site_name: string;
   site_description: string;
+  etag: string;
 };
 
 /**