ℹ️ NOTE

This a proof of concept, and overly complicated for a real world system

https://lucid.app/documents/view/80b791ef-6597-4280-adef-fe815bbe0f2c

The API is written using Azure Functions V3, I chose to do it this way as it hands over the responsibility of scaling and availability to Azure while lowering running costs. I'm adding a document to Cosmos DB for each document and the files themselves are saved to Azure blob storage.

I realise that I could have used Azure Storage Tables for the documents, or just listed the documents from blob storage directly but I wanted to use multiple services working with each other.

• Azure Functions Core Tools (Optional) - Work with Azure Functions Core Tools
• Dot net core 3.1
• Azure Storage Emulator - Use the Azure Storage Emulator for development and testing
• Cosmos Emulator - Install and use the Azure Cosmos emulator for local development and testing

Cosmos DB
Copy the primary connection string from your local cosmos emulator https://localhost:8081/_explorer/index.html into the setting CosmosConnectionString in local.settings.json

ℹ️ The database and collection will be created automatically.

If you have the Azure Functions Core Tools installed then you can open a terminal window and run func start from .\DocumentManager.Api, alternatively you can open the solution in Visual Studio and run the DocumentManager.Api project.

You should see the following output if using Azure Functions Core Tools:

[01:34:30 INF] Initializing function HTTP routes
Mapped function route 'api/delete/{filename}' [delete] to 'Delete'
Mapped function route 'api/download/{filename}' [get] to 'Download'
Mapped function route 'api/list/{sortProperty?}/{sortDirection?}' [get] to 'List'
Mapped function route 'api/Upload' [post] to 'Upload'

[01:34:30 INF] Host initialized (127ms)

Functions:

        Delete: [DELETE] http://localhost:7071/api/delete/{filename}

        Download: [GET] http://localhost:7071/api/download/{filename}

        List: [GET] http://localhost:7071/api/list/{sortProperty?}/{sortDirection?}

        Upload: [POST] http://localhost:7071/api/Upload

        CreateDocument: blobTrigger

For detailed output, run func with --verbose flag.
[01:34:30 INF] Host started (174ms)
[01:34:30 INF] Job host started
Hosting environment: Production
Content root path: D:\Projects\Mine\document-management-api-example\DocumentManager.Api\bin\output
Now listening on: http://0.0.0.0:7071
Application started. Press Ctrl+C to shut down.

POST /api/upload
Example request:

{
    "filename": "example1.pdf",
    "data": "JVBERi0xLj..."
}

Example response:

{
    "filename": "example1.pdf",
    "size": 13264
}

The data property should be filled with the base64 encoded file data, there are sites to help with this step such as https://www.browserling.com/tools/file-to-base64

201 Created, 400 Bad Request, 500 Internal Server error

• 5MB Upload limit
• Only application/pdf files are allowed

GET /api/list
GET /api/list/{sortProperty}
GET /api/list/{sortProperty}/{sortDirection}

200 Success, 500 Internal Server error

Available sort properties: DateCreated, Filename, ContentType, Bytes
Available sort directions: Ascending, Descending

A list of documents will be listed from Cosmos, sortProperty and sortDirection are optional and will order by DateCreated Ascending by default.

Example response:

[
    {
        "id": "b584d8e5-07d7-431d-a407-12ad92af1fcb",
        "filename": "example1.pdf",
        "dateCreated": "2020-10-24T19:09:37.4478874Z",
        "bytes": 13264,
        "contentType": "application/pdf"
    },
    {
        "id": "77b36efb-59ff-4de7-b0f3-b81c7d8a37b2",
        "filename": "example2.pdf",
        "dateCreated": "2020-10-24T19:19:35.8625293Z",
        "bytes": 13264,
        "contentType": "application/pdf"
    }
]

GET /api/download/{filename}

200 Success, 404 Not found, 500 Internal Server error

Response: A memory stream will be returned, if you use postman there is the option to save the response as a file.

DELETE /api/delete/{filename}

200 Success, 404 Not found, 500 Internal Server error

Logs are saved to text files in .\Logs