JMMC/ObsPortal: Software architecture

Questions

Several points must be discussed in order to define an architecture.

Usages

• What do we want to do?
  • Using Aspro2
    • To find past observations about selected targets (with the same interferometer, instrument, configuration, ...)
    • To display these observations by plotting points under "Observability" and "UV coverage" tabs
  • Using a Web portal
    • ???

Data

• On which metadata to search and filter the observations?
  • target name
  • target coordinates
  • ...
• Which metadata to display for one observation?
  • To plot the observation under "Observability" tab
    • ...
  • To plot the observation under "UV coverage" tab
    • ...
  • To show inside a tooltip
    • ...
• Where to find the source metadata?
  • Extracted from headers provided by the ESO Archive
  • See the page JmmcObsPortalDataAnalysis for the keywords mapping

Protocols and links between software parts

• Aspro2 <--> "ObsPortal System"
  • How to query the "ObsPortal System" from Aspro2?
    • How?
      • Directly
      • Via A2P2
    • Which protocol?
      • API REST on HTTP/HTTPS
      • SAMP
      • TAP
    • Which parameters?
      • See the question "On which metadata to search and filter the observations?"
  • How to send the query results to Aspro2?
    • How?
      • Directly
      • Via A2P2
      • By a generated intermediary file (OBXml / Asprox)
    • Which protocol?
      • API REST on HTTP/HTTPS
      • SAMP
      • TAP
    • Which data structure?
      • JSON
      • VOTable
      • OBXml
      • Asprox
      • ...
    • Which properties to return?
      • See the questions "Which metadata to display for one observation?"

• OiDB <--> "ObsPortal System"

Modeling method

The architecture will be designed using the method described on https://c4model.com and the online modeling tool draw.io

Current context around OiDB

Source: JMMC-ObsPortal-C1-current.drawio

ObsPortal architecture

Level 1: System context

A System Context diagram provides a starting point, showing how the software system in scope fits into the world around it.

Source: JMMC-ObsPortal-C1.drawio

Comments

At this step, a first question is related to the integration and the future role of OiDB and A2P2...

Level 2: Container

A Container diagram zooms into the software system in scope, showing the high-level technical building blocks.

Proposition 1

Source: JMMC-ObsPortal-C2.drawio

The "Observation system" will be composed by:

• a dedicated database
• a backend application ("Core Application")
• a frontend application ("Web Application"), if needed. Il may be part of "Core Application"...

• an API application proxying requests from Aspro2 to the database
• a "data feeder" application retrieving new metadata from sources (ESO, CHARA, ...) and inserting the selected properties into the database

Level 3: Component

A Component diagram zooms into an individual container, showing the components inside it.

Level 4: Code

A code (e.g. UML class) diagram can be used to zoom into an individual component, showing how that component is implemented.

-- Philippe Bollard - 2019-11-26