Developer Documentation

• Core API (ixmp4.core)
• Data Layer (ixmp4.data)
• Web Application Server (ixmp4.server)
• Command Line Interface (ixmp4.cli)
• Databases (ixmp4.db)
• Database Utilities (ixmp4.db.utils)
• Configuration
• Tests

Package/Folder Structure

.
├── ixmp4
│   ├── cli                 # cli
│   ├── conf                # configuration module, loads settings etc.
│   ├── core                # contains the facade layer for the core python API
│   ├── data
│   │   ├── abstract        # ABCs for data source models and repositories
│   │   ├── api             # data source implementation for the web api
│   │   ├── backend         # data source backends
│   │   └── db              # data source implementation for databases (sqlalchemy)
│   ├── db                  # database management
│   ├── server              # web application server
│       └── rest            # REST endpoints
├── run                     # runtime artifacts
└── tests                   # tests

Architecture

ixmp4 provides a Python API, a REST API and a compatibility layer for Postgres and SQLite Databases. The Python API can interact with databases directly or use the REST API of a compatible ixmp4 server instance.

-> calls ->
                         Web or SQL
         Platform         Backend                    Server       SQL Backend
   │  ┌────────────┐   ┌───────────┐    ┌─    │   ┌──────────┐   ┌───────────┐  ─┐      │  ┌─┐
 P │  │            │   │           │    │     │   │          │   │           │   │    S │  │ │
 y │  │ ┌────────┐ │   │ ┌───────┐ │    │   R │   │ ┌──────┐ │   │ ┌───────┐ │   │    Q │  │D│
 t │  │ │        │ │   │ │       │ │  ┌─┘   E │   │ │Endp. │ │   │ │       │ │   └─┐  L │  │a│
 h │  │ │Facade  │ │   │ │Model  │ │  │     S │   │ └──────┘ │   │ │Model  │ │     │  A │  │t│
 o │  │ └────────┘ │   │ ├───────┤ │  │     T │   │          │   │ ├───────┤ │     │  l │  │a│
 n │  │            │   │ ├───────┤ │  │       │   │ ┌──────┐ │   │ ├───────┤ │     │  c │  │b│
   │  │    ...     │   │ │       │ │  │     A │   │ │Endp. │ │   │ │       │ │     │  h │  │a│
 A │  │            │   │ │Repo.  │ │  └─┐   P │   │ └──────┘ │   │ │Repo.  │ │   ┌─┘  e │  │s│
 P │  │            │   │ └───────┘ │    │   I │   │          │   │ └───────┘ │   │    m │  │e│
 I │  │            │   │    ...    │    │     │   │   ...    │   │    ...    │   │    y │  │ │
   │  └────────────┘   └───────────┘    └─    │   └──────────┘   └───────────┘  ─┘      │  └─┘

        ixmp4.core        ixmp4.data                ixmp4.server      ixmp4.data

Note that a REST SDK in another programming language would have to implement only the components before the bracketed part of the diagram (ixmp4.data.api + optionally a facade layer).

Overall both the “facade” layer and the “data source” layer are split into “models” (representing a row in a database or a json object) and “repositories” (representing a database table or a collection of REST endpoints) which manage these models.