The proposed infrastructural solution consists of the following modules:
- Angular front-end application
- HTTP Archive API
- Identity Server API
- MSSQL Database for storing users
- Mongo DB for storing files
One of the key requirements of the task is to create a scalable application. The proposed approach will allow this. We are using distributed authentication, so if we can scale our application independetly. The HTTP Archive API can be scaled horisontally (no state, caching or other potential problems). Ideally it could be containerized and scaled more easily. The har files are stored in a Mongo database, which is very scalable with support for sharding and replicas. Also it's very performant. The file content is stored in it. It could go to a blob storage, but this solution requires more time. Bellow is an example approach for scaling the application.
The current infrastructure is simple, due to the limited time, but it allows further scaling. An example approach would be as follows:
Here is an example file stored in the Mongo database:
{
"id": "61c311c48555373cabf7e398",
"filePath": "Folder1/FolderA/FolderB",
"userId": "35289544-4adc-4880-bb10-34ec646d4fe7",
"createdOn": "2021-12-22T11:53:40.918Z",
"fileContent": "{...actial .har file content...}",
"fileName": "www.dnevnik.bg.har",
"sharedWith": ["user1@test.com", "user2@test.com"]
}
As seen in the file above, the folders are virtual (like in the blob storages). We are preserving only the path to the file. So we don't have an entity for the folders. We are keeping only files with virtual paths. This allows more performant file storing and fetching.
- error handling can be improved with some global exceptions handler on the API side.
- ideally this can be containerized for easier maintenace and deployment
- the styling on the FE can be improved
- for better scalability this could go to a sreverless solution with azure functions or AWS lambdas. Currently if we have performance issues with reading we can scale the whole app. If we are using functions, we can scale only the problematic function.