Skip to content

Latest commit

 

History

History
85 lines (65 loc) · 3.46 KB

architecture.adoc

File metadata and controls

85 lines (65 loc) · 3.46 KB

Architecture

components
Caution
 if not otherwise specified, we are using Twitter Futures, not Scala Futures!

  • the frontend (the React SPA) is deployed as independent container and uses AJAX for communication with the backend.

  • Login and authentication is fully provided through AuthSvc.

  • the IDE features: compile, autocomplete, simulate, .. are provided through MoPE. All IDE related requests are forwarded to MoPE.

  • Modelica files are saved onto disk, specifically into a shared docker volume.

Redis Usage

We are using redis as cache, as well as session store:

  • the user model is cached because we need it for validating authentication tokens.

  • autocomplete suggestions are cached.

  • mapping session UUIDs to its session model is done using redis: the redis key is the session UUID and its value is the session model. This removes any state from the Webmodelica backend and moves it into redis. Without state, we can easily scale the backend servers.

Sessions

A session is a connection between a project, a running MoPE project instance and the project directory containing the modelica files. MoPE assigns each open project an ID so does Webmodelica. Webmodelica assigns a UUID, whereas MoPE assigns integers. The project directory is currently resolved as <owner>_<project name>.

The session model is saved into redis to avoid state in Webmodelica.

File paths & shared volume

The Webmodelica backend and MoPE container share a volume to access the project files. Because its a shared volume, that is mounted somewhere in the container, a path in the Webmodelica backend isn’t necessarily the same as in MoPE. If the volume is mounted into Webmodelica at /data and in MoPE at /home/openmodelica/data the paths aren’t the same:

Example 1. A simple Path Example

  • path as seen from Webmodelica: /data/tom_testProject/utils/fac.mo

  • path as seen from MoPE: /home/openmodelica/data/tom_testProject/utils/fac.mo

However, for compiling modelica files, we need the absolute path to the currently open file. This path must be valid for MoPE and not for Webmodelica:

A compilation request for MoPE.
http POST mope:9001/mope/project/0/compile

{ "path": "/home/openmodelica/data/tom_testProject/utils/fac.mo" } (1)
The response from MoPE.
[{
  "end": {
      "column": 2,
      "line": 4
  },
  "file": "/home/openmodelica/data/tom_testProject/utils/fac.mo", (1)
  "message": "Missing token: SEMICOLON",
  "start": {
      "column": 2,
      "line": 4
  },
  "type": "Error"
}]

  1. This path is known in MoPE, but not in Webmodelica. In Webmodelica it would be: /data/tom_testProject/utils/fac.mo.

The compilation response contains paths to modelica files, that are valid in the MoPE context but not in Webmodelica. Furthermore users don’t care about the absolute path. Users are only interested in the path starting at the project directory. All of this means that we need a mapping mechanism, that converts paths between this two root directories.

The webmodelica.services.MopeService.PathMapper trait in webmodelica/services/MopeService.scala describes such a mapper.

Important
 The PathMapper needs both paths: the webmodelicas path and MoPE path. These paths are configured in webmodelica.conf at mope.data.host-directory and mope.data.bind-directory. Here the host-directory is the Webmodelica path and bind-directory is the MoPE path.