Add NGSI-LD multi-measures support

[jason-fox]

• split NGSI-v1, NGSI-v2 and NGSI-LD into separate files
• Move common REST functions into restUtils.js
• ensure that ids are URNS (adding urn:ngsi-ld: where necessary)
• Use Batch Upsert endpoint throughout ( /ngsi-ld/v1/entityOperations/upsert/) instead of PATCH update
• Update test expectations
• Split NGSI v2 and NGSI-LD registrations

[fgalan]

PR #843 has been merged and base branch changed to feature/842_ngsi_ld in this PR.

So I understand you should upgrade jason-fox:feature/ngsi-ld-multimeasure with telefonicaid:feature/842_ngsi_ld

[fgalan]

Leftover comment?

[jason-fox]

Yes, but - the multiple instances of console.error (commented out) are being used to help generate the responses for the tests.

When the final PR is processed I'll remove them all.

[fgalan]

Noted in the accumulative PR - #849 (comment)

NTC with regards this PR

[fgalan]

I think the PR is ok (except for a couple of very minor comments easy to fix)

However, regarding:

split NGSI-v1, NGSI-v2 and NGSI-LD into separate files

I like the refactor to move separate parts into -NGSI-LD.js -NGSI-v1.js and- NGSI-v2.js files in different parts. However, I wonder about the usual question: which impact could have this change into other existing PRs? Could you analyze it a little bit and provide feedback, pls?

[jason-fox]

split NGSI-v1, NGSI-v2 and NGSI-LD into separate files

This is very simple - All of the split /devices, /ngsi and /northBound files are to do with NGSI Interactions only - these are all defined by the relevant specifications, so there is zero likelihood that another PR will be amending them. It will have NO impact on the other PRs. The split has not changed the functionality of the underlying code (since none of the v1 or v2 tests has been modified) - its merely cut-paste rearrangement.

Going forward, reducing the file size means that it is even less likely that a clash will occur - besides which it is practically impossible to read a single 2000+ line file with interleaving implementations of three near duplicates of each function with only fractional differences between them. [sigh]

It also allows for:

• the v1/v2/ld flag checking to occur once only - see jason-fox@2f2caea. (later PR)
• a comparison to be made between the code coverage for v1, v2 and LD in coveralls.

[jason-fox]

Note that things like #835 can touch files like deviceService.js, but this is common functionality which applies to v1 v2 and LD and therefore the relevant functions (e.g. registerDevice(), prepareDeviceData() ) remain unchanged in my PR and in place in the root file.

[fgalan]

Ok. The rationale is sound :)

LGTM