Epic/hwsc-app-gateway-svc AddDocument

[faraonc]

Let us say Chrome wants to add a new document. At this point Chrome has the current User object, and it knows the user's uuid already.

1. The user fills up the form in the website.
2. Grabs the fields in the form and make a Document object. image_urls_map, audio_urls_map, video_urls_map, & file_urls_map are not filled up because there is no means of generating duid and fuids in the browser, therefore we have to send lists of urls.
3. Chrome calls app-gateway-svc's AddDocument() with the following

message AppGatewayRequest{
    hwsc.User user = N; //this is not a complete User object, it may only have uuid
    hwsc.Document doc = N; //this is not a complete Document object, it may only have duid
    repeated string image_urls = N;
    repeated string audio_urls = N;
    repeated string video_urls = N;
    repeated string file_urls = N;
}

4. app-gateway-svc calls document-svc's CreateDocument() which returns the newly Created Document with a now generated duid and fuids.
5. app-gateway-svc calls user-svc's GetUser, which returns a full User object A with password as empty string.
6. app-gateway-svc modifies the User object A, and adds the DUID in the:

map<string, UserDocumentMetadata > user_documents = 7;

7. app-gateway-svc calls user-svc's UpdateUser, which returns a full User object with password as empty string.
8. 1. OPTION 1 - app-gateway-svc returns 2 objects (updated User and updated Document) to Chrome
   2. OPTION 2 - app-gateway-svc calls document-svc ListUserDocumentCollection, returns a list of user documents.
9. Chrome renders page.