API request using FunctionIInvokeAfter - stop delays once all the data is loaded

Hi pmershon ,
Based on your description and the code provided, since each API call is very time-consuming, please minimize the number of calls by batching requests whenever possible. Although the CrossRef API does not support multiple queries in a single request, you can still optimize by reducing unnecessary steps in your queries.
You can try creating a custom function

let
    fxGetCrossRefDOI = (Title) =>
        let
            baseURL = "https://api.crossref.org/works",
            query = Uri.EscapeDataString(Title),
            URL = baseURL & "?rows=1&sort=relevance&query.bibliographic=" & query & "&select=title,container-title,DOI,ISSN&filter=type:journal-article",
            response = Json.Document(Web.Contents(URL))
        in
            response
in
    fxGetCrossRefDOI

Of course, you can also use Table.Buffer, which helps to minimize the number of times you have to read data from the source. You can use load data into memory, which may speed up subsequent steps
Table.Buffer - PowerQuery M | Microsoft Learn
You can also refer to this document to learn how to use the Rest API
TripPin 2 - REST - Power Query | Microsoft Learn

Best regards,
Albert He

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