DHF using Entity-services design of envelope

Question

I am using DHF with entity-services. I was wondering if an envelope contains multiple entity instances can I have the envelope be designed as below

<envelope xmlns="http://marklogic.com/entity-services">
  <headers>
  </headers>
  <triples>
  </triples>
  <instance>
        <info>
          <title>target</title>
          <version>1.0.0</version>
        </info>
        <target:target xmlns:target="http://schemas.abbvienet.com/entity/target">
            ....
        </target>
  </instance>
  <instance>
        <info>
          <title>core</title>
          <version>1.0.0</version>
        </info>
        <core:core xmlns:core="http://schemas.abbvienet.com/entity/core">
            ....
        </core>
  </instance>
  <attachments>
  </attachments>
</envelope>

Notice the 2 instance tags for 2 instances.

Is this valid, as I was not able to find the recommendation of envelope design, like xsd ?Is this a good design of the instances in the envelope or is there a better way ? Or can I have like this

<envelope xmlns="http://marklogic.com/entity-services">
  <headers>
  </headers>
  <triples>
  </triples>
  <instance>
    <info>
      <title>target</title>
      <version>1.0.0</version>
    </info>
    <target:target xmlns:target="http://schemas.abbvienet.com/entity/target">
                    ....
    </target>
    <core:core xmlns:core="http://schemas.abbvienet.com/entity/core">
                    ....
    </core>
  </instance>
  <attachments>
  </attachments>
</envelope>

I want to use the es api for canonicalizing the entity

Answer 1

Currently the DHF (and entity services) support a paradigm of one instance per document following the envelope pattern.

If you need the same attachments/triples/header support for multiple instances of an entity (or multiple entities) - just split them up and attach them.

Also, you really shouldn't be modifying the instance portion of the generated envelope:

<es:envelope xmlns:es="http://marklogic.com/entity-services">
  <es:instance>
    <es:info>
      <es:title>Person</es:title>
      <es:version>1.0.0</es:version>
    </es:info>
    <Person>
      <id>1234</id>
      <firstName>George</firstName>
      <lastName>Washington</lastName>
      <fullName>George Washington</fullName>
    </Person>
  </es:instance>
  <es:attachments>
    <person>
      <pid>1234</pid>
      <given>George</given>
      <family>Washington</family>
    </person>
  </es:attachments>
</es:envelope>

But you can add information elsewhere outside the instance as needed. More information on entity services relating to your question can be found here: https://docs.marklogic.com/guide/entity-services/instances#id_67461

There is, currently, a bit of a gap between ES and DataHub that we are actively working on closing, which is why I encourage you not to modify the default instance setup and keep one instance per envelope document.