Callservice dataset example

[1000TurquoisePogs]

Proposed changes

This adds a simple dataservice which calls the hello dataservice and returns its content. The purpose is to show how someone can use the callservice API.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

PR Checklist

Please delete options that are not relevant.

• If the changes in this PR are meant for the next release / mainline, this PR targets the "staging" branch.
• My code follows the style guidelines of this project (see: Contributing guideline)
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• New and existing unit tests pass locally with my changes
• video or image is included if visual changes are made
• Relevant update to CHANGELOG.md
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works, or describe a test method below

Testing

Try calling POST /ZLUX/plugins/org.zowe.zlux.sample.angular/services/callservice/_current/ with various bodies, such as

1. no body
2. simple text
3. simple JSON
   You should see that the contents returned are a JSON message that includes within a message that is identical to what you would have received if you had used the same body to call POST /ZLUX/plugins/org.zowe.zlux.sample.angular/services/hello/_current/
   This will prove that the callService API call was successful.

Further comments

[lchudinov]

It works fine to me so I approve it.

[lchudinov]

I am curious why do we need to pass text/plain unconditionally. What if we pass an original content-type as req.body['content-type'] or omit it at all?

[1000TurquoisePogs]

Good point, its an oversight. I will fix it.