marklogic mlcp 自定義轉換將聚合文檔拆分為多個文件 (marklogic mlcp custom transform split aggregate document to multiple files)

問題描述

marklogic mlcp 自定義轉換將聚合文檔拆分為多個文件 (marklogic mlcp custom transform split aggregate document to multiple files)

I have a JSON "aggregate" file that I want to split up and ingest as multiple documents into MarkLogic using mlcp.

I want to transform the content during ingestion using javascript.

My JSON file looks something like this:

{
  "type": "FeatureCollection",
  "features": [
    {blobA}, {blobB}, {blobC} ......
    ]
 }

...and I want to run this file through MLCP so that each document contains an item in the array.

i.e. One document will contain {blobA}, another will contain {blobB}, and another will contain {blobC}....and so forth.

How do I write my custom .sjs transform module?

參考解法

方法 1:

Check out the example here: http://docs.marklogic.com/guide/mlcp/import#id_26044

The original input document is expected to be of the following form:

{ uri: string,
  value: node
}

That is also the expected output form for each document. You'll also want your return to be of type document‑node, since you want mlcp to split it up and ingest it as JSON documents.

So, your .sjs custom transform module will look something like this....

function splitFeatures(doc) {
  const features = doc.value.toObject().features;
  return xdmp.arrayValues(
    features.map(function(feature) {
      return {
        uri: '/path/itemhere‑' + xdmp.random() + '.json',
        value: xdmp.toJSON(feature)
      }
    })
  );
}

exports.transform = splitFeatures;

As an aside, this is a useful resource when working with JSON in MarkLogic.

(by jennifer、jennifer)

參考文件

1. marklogic mlcp custom transform split aggregate document to multiple files (CC BY‑SA 2.5/3.0/4.0)