Parse messages from the queue into real tags/fields for influxDB

[bodom0015]

Problem

InfluxDB consumer currently just inserts a large JSON string into the database - this structure is a non-queryable, and therefore not useful.

Approach

Instead, parse the JSON message into tags/fields that Influx understands. Tags are indexed, and therefore more performant when used as a search query. At least one field is required - these are meant contain all other measurement data.

Noting this section from the "Discussion" section of the docs:

Tags are optional. You don’t need to have tags in your data structure, but it’s generally a good idea to make use of them because, unlike fields, tags are indexed. This means that queries on tags are faster and that tags are ideal for storing commonly-queried metadata.

Tags (indexed):

• type
• category
• service_name
• user_id
• author_id
• extractor_name

Fields:

• resource_id
• dataset_id
• dataset_name
• author_name
• user_name
• resource_name
• size

How to Test

Prerequisites:

• RabbitMQ running locally
• Docker

See other PR for testing steps