Location & Geometry QuerySet Examples¶

These examples demonstrate how to query and traverse the ProjectSite, Location, AssetLocation, ModelDefinition, SubAssembly, BuildingBlock, and related geometry models. All field names and relationships reflect the exact backend schema.

Shell Setup¶

from locations.models import AssetLocation, Location, ProjectSite
from geometry.models import (
    BuildingBlock,
    DistributedMass,
    LumpedMass,
    Material,
    ModelDefinition,
    SubAssembly,
    TubularSection,
)

Data Model Overview¶

Locations Hierarchy¶

ProjectSite — top-level site containing multiple locations.
Location — a named position within a site (FK → ProjectSite).
AssetLocation — inherits from Location via a one-to-one link on location_id (multi-table inheritance).

Geometry Hierarchy¶

ModelDefinition — a geometry model version (FK → ProjectSite via project).
SubAssembly — a structural component linked to a model definition and an asset location.
BuildingBlock — an element of a sub-assembly.
TubularSection — a building block specialization with a material FK.
LumpedMass — a point mass building block.
DistributedMass — a distributed mass building block.
Material — standalone material properties.

Entity Relationship Diagram¶

erDiagram
    ProjectSite {
        int id PK
        string title
        string slug
        string description
        boolean active
        string visibility
        json additional_data "nullable"
        int created_by FK
        int modified_by FK
    }

    Location {
        int id PK
        int projectsite_id FK
        int created_by FK
        int modified_by FK
    }

    AssetLocation {
        int location_id PK "inherits Location"
        string title
        float northing
        float easting
    }

    ModelDefinition {
        int id PK
        int project_id FK "→ ProjectSite"
        string title
        string description
    }

    SubAssembly {
        int id PK
        int model_definition_id FK
        int asset_location_id FK
    }

    BuildingBlock {
        int id PK
        int sub_assembly_id FK
    }

    TubularSection {
        int building_block_id PK
        int material_id FK
    }

    LumpedMass {
        int building_block_id PK
    }

    DistributedMass {
        int building_block_id PK
    }

    Material {
        int id PK
    }

    ProjectSite ||--o{ Location : "projectsite_id"
    Location ||--o| AssetLocation : "location_id"
    ProjectSite ||--o{ ModelDefinition : "project_id"
    ModelDefinition ||--o{ SubAssembly : "model_definition_id"
    AssetLocation ||--o{ SubAssembly : "asset_location_id"
    SubAssembly ||--o{ BuildingBlock : "sub_assembly_id"
    BuildingBlock ||--o| TubularSection : "building_block_id"
    BuildingBlock ||--o| LumpedMass : "building_block_id"
    BuildingBlock ||--o| DistributedMass : "building_block_id"
    Material ||--o{ TubularSection : "material_id"

Query Flow Diagrams¶

Project Hierarchy¶

flowchart LR
    PS[ProjectSite] --> L[Location] --> AL[AssetLocation]

Full Geometry Traversal¶

flowchart LR
    PS[ProjectSite] --> MD[ModelDefinition]
    MD --> SA[SubAssembly]
    AL[AssetLocation] --> SA
    SA --> BB[BuildingBlock]
    BB --> TS[TubularSection]
    BB --> LM[LumpedMass]
    BB --> DM[DistributedMass]
    TS --> MAT[Material]

ProjectSite Queries¶

# Retrieve all project sites.
ProjectSite.objects.all()

# Filter by slug.
ProjectSite.objects.filter(slug="nobelwind")

# Filter by title (case-insensitive).
ProjectSite.objects.filter(title__icontains="nobelwind")

# Active sites only.
ProjectSite.objects.filter(active=True)

# Get a single site by slug.
site = ProjectSite.objects.get(slug="nobelwind")

Real Data Example¶

# The real Nobelwind record:
# id=31, slug="nobelwind", title="Nobelwind", active=False
site = ProjectSite.objects.get(slug="nobelwind")
print(site.title)       # "Nobelwind"
print(site.description) # "Nobelwind is the fourth project..."

Location Queries¶

# All locations for a project site.
Location.objects.filter(projectsite__slug="nobelwind")

# With the project site joined (avoids N+1).
Location.objects.select_related("projectsite").filter(
    projectsite__slug="nobelwind"
)

Reverse Relations from ProjectSite¶

site = ProjectSite.objects.get(slug="nobelwind")

# All locations belonging to this site (reverse FK).
site.location_set.all()

# Count locations.
site.location_set.count()

AssetLocation Queries¶

AssetLocation inherits from Location through multi-table inheritance (location_id is both the PK and the FK to Location).

# All asset locations.
AssetLocation.objects.all()

# Asset locations for a specific project site (traverses through Location).
AssetLocation.objects.filter(projectsite__slug="nobelwind")

# With the parent location joined.
AssetLocation.objects.select_related("location_ptr")

# Access the parent Location fields directly.
asset = AssetLocation.objects.get(pk=435)
print(asset.title)      # e.g. "BBA01"
print(asset.northing)   # coordinate
print(asset.easting)    # coordinate

Reverse Relations from ProjectSite¶

site = ProjectSite.objects.get(slug="nobelwind")

# All asset locations for this site.
AssetLocation.objects.filter(projectsite=site)

ModelDefinition Queries¶

# All model definitions.
ModelDefinition.objects.all()

# Filter by project site.
ModelDefinition.objects.filter(project__slug="nobelwind")

# Filter by title.
ModelDefinition.objects.filter(title="as-built Belwind")

# Get a specific model definition.
model_def = ModelDefinition.objects.get(pk=12)
print(model_def.title)   # "as-built Belwind"
print(model_def.project)  # ProjectSite reference

Reverse Relations¶

site = ProjectSite.objects.get(slug="nobelwind")

# All model definitions for this site.
site.modeldefinition_set.all()

SubAssembly Queries¶

# All sub-assemblies for a model definition.
SubAssembly.objects.filter(model_definition_id=12)

# Sub-assemblies with their model definition and asset location joined.
SubAssembly.objects.select_related(
    "model_definition", "asset_location"
)

# Deep join: sub-assemblies for a project site.
SubAssembly.objects.filter(
    model_definition__project__slug="nobelwind"
)

# Sub-assemblies at a specific asset location.
SubAssembly.objects.filter(asset_location_id=435)

Reverse Relations¶

model_def = ModelDefinition.objects.get(pk=12)

# All sub-assemblies in this model definition.
model_def.subassembly_set.all()

# From an asset location.
asset = AssetLocation.objects.get(pk=435)
asset.subassembly_set.all()

BuildingBlock Queries¶

# All building blocks for a sub-assembly.
BuildingBlock.objects.filter(sub_assembly_id=100)

# Deep join: building blocks for a project site.
BuildingBlock.objects.filter(
    sub_assembly__model_definition__project__slug="nobelwind"
)

# With the sub-assembly joined.
BuildingBlock.objects.select_related("sub_assembly")

Full Traversal: ProjectSite → Materials¶

# Traverse from project site through geometry down to materials.
# This demonstrates a deep join across the full hierarchy.
TubularSection.objects.filter(
    building_block__sub_assembly__model_definition__project__slug="nobelwind"
).select_related("material", "building_block__sub_assembly__model_definition")

Reverse: From Material to ProjectSite¶

material = Material.objects.get(pk=1)

# All tubular sections using this material.
material.tubularsection_set.all()

# Traverse up to project sites.
ProjectSite.objects.filter(
    modeldefinition__subassembly__buildingblock__tubularsection__material=material
).distinct()

Prefetching for Efficient Batch Access¶

# Efficiently load a project site with its full geometry tree.
sites = ProjectSite.objects.prefetch_related(
    "location_set__assetlocation__subassembly_set__buildingblock_set"
).filter(slug="nobelwind")

for site in sites:
    for location in site.location_set.all():
        if hasattr(location, "assetlocation"):
            for sa in location.assetlocation.subassembly_set.all():
                for bb in sa.buildingblock_set.all():
                    print(site.title, sa, bb)

# Prefetch model definitions with their full sub-assembly chain.
model_defs = ModelDefinition.objects.prefetch_related(
    "subassembly_set__buildingblock_set__tubularsection__material"
).filter(project__slug="nobelwind")

for md in model_defs:
    for sa in md.subassembly_set.all():
        for bb in sa.buildingblock_set.all():
            if hasattr(bb, "tubularsection"):
                print(md.title, bb.tubularsection.material)

SDK Alignment¶

The core owi-metadatabase SDK provides LocationsAPI and GeometryAPI for HTTP access to these models.

LocationsAPI¶

from owi.metadatabase.locations.io import LocationsAPI

api = LocationsAPI(api_root="https://owimetadatabase-dev.azurewebsites.net/api/v1",
                   token="your-api-token")

# Fetch all project sites.
api.get_projectsites()

# Get details for a specific site.
api.get_projectsite_detail(projectsite="Nobelwind")

# Get all asset locations for a site.
api.get_assetlocations(projectsite="Nobelwind")

GeometryAPI¶

from owi.metadatabase.geometry.io import GeometryAPI

api = GeometryAPI(api_root="https://owimetadatabase-dev.azurewebsites.net/api/v1",
                  token="your-api-token")

# Get model definition id for a site.
api.get_modeldefinition_id(
    projectsite="Nobelwind",
    model_definition="as-built Nobelwind",
)

# Fetch sub-assemblies for a model definition.
api.get_subassemblies(model_definition_id=12)

# Fetch building blocks for a sub-assembly.
api.get_buildingblocks(sub_assembly_id=100)