# Labels System

- Labels depends on a booking existing?
- Use the booking id as the root identifier for labels?
- Use api standardisation
- Flags vs status
- `"IsReady":true` vs `"Status":"Ready"`
- Raise webhooks, sockets and events.
- Support disabling labels (ie when a booking is cancelled, disable label downloads).

# Questions
- What about customs docs?
- What about commercial invoices?
- We can send digital invoices or;
- customer can download a printable version
- Can we group all types of booking together?
- How do we know which formats are available for a spceific courier?
- If a label within a batch fails does the entire file fail?
- Can we change the batches between request and response?
- Do labels need any additional information or just booking info? (SKU, etc).
- Lots of overlap with invoices

# Document API

## Reqs

- Access rules / Auditing
- document worker library (and react library) supporting :
- Progress reporting
- Access rules (HMAC & )
- Invalidation / expiry
- Caching
- Auditing
- Invalidation
- Archive rules

- Different document types are different workers (query api style)

## Notes
- Use prns for refs
- Allows us to use bookingids, orderlines, etc.
- Allows a system to request a doc type with an unsupported prn.
- We may need to hard-code this mapping or have a db table of prn to system mappings.

## Endpoints

/{tenant}/labels

### Request

    {
        "labels" : [{
            "refs" : ["prn:booking:123", "prn:customerid:234"],
            "type" : "prn:label",
            "format" : "pdf",
            "tags" : ["IncludeCoverPage"],
            // onerror": "skip"
            "tagos" : {
                "overrides": {
                    "cobranding" : "s3://..."
                }
            }
        },
        {
            "refs" : ["prn:booking:123"],
            "format" : "qrcode",
            "tags" : ""
        },
        {
            "refs" : ["prn:123", "prn:234"],
            "type" : "customs",
            "format" : "pdf",
            "tags" : [],
            "tagos" : { }
        }]
    }

### Response

{
    "Result" :  {
        "Labels": [
            {
                "BookingIds" : ["prn:123", "prn:234"],
                "IsReady" : true,
                "State" : "Ready",
                "link" : "s3://",
                "Tags" : ["IncludeCoverPage"],
                "Tagos" : []
            }, 
            {
                "BookingIds" : ["prn:123"],
                "IsReady" : false,
                "State" : "Waiting",
            }]

    },
    // api standards
    "Success": true,
    "ValidationErrors" : {}
}

## Worker Package

 public async Task FunctionHandler(EventMessage<GenerateDocumentCommand> input, ILambdaContext context)
 {
     // Sets status to "started".
     // Handles timeouts
     // When disposed if the document isn't complete it will set it to error
     
     using (_docsApi.Begin(input.Id))
     
     try 
     {
         var docurl = GenerateDocument(input);
         _docsApi.Success(input, docurl);
     }
     catch (Exception ex)
     {
         _docsApi.Fail(input, ex);
     }
 }
 
 
 // we can support progress..
 
 
 string GenerateDocument(GenerateDocumentCommand event)
 {
     _docsApi.Progress("Started", 0);
     
     var document = new PdfDocument("s3-bucket");
     for(int i=0; i < event.Refs.Count; i++)
     {
         AppendDocumentToFile(event.refs[i], document);
         _docsApi.Progress(i / event.Refs.Count);
     }
     
     return document.S3Path;
 }