Model Import Algorithm and Sequence

Specification for importing models into EMEP. Covers the ModelLoader algorithm, hash verification, ArtifactStore staging, and the full interaction sequence with external sources.

Model import is the first step in the EMEP lifecycle. This page specifies the ModelLoader algorithm, the interaction sequence with external model sources, and the exact outputs that feed into the ModelRegistry.

ModelImport Algorithm

The ModelLoader executes this flowchart for every import request.

Import Sequence Diagram

This sequence shows the full interaction between the user, ModelLoader, external source, ArtifactStore, and ModelRegistry.

Import Manifest

The manifest returned to the caller and stored in ModelRegistry contains:

Field	Description
model_id	UUID assigned by ModelRegistry
source_uri	Original source (HF repo, mirror, local path)
revision	Tag, branch, or commit hash
artifact_uri	Path in ArtifactStore
metadata	Architecture, size, layer count, etc.
hashes	SHA-256 of every weight file
import_time	ISO 8601 timestamp
status	IMPORTED

Failure Modes

Failure	Cause	Recovery
Invalid metadata	Source returned malformed JSON	Retry or fail
Incomplete download	Network interruption	Resume or restart
Hash mismatch	Corruption or tampering	Reject and alert
Corrupt archive	Unpack error	Reject and alert
Staging conflict	Concurrent import of same model	Deduplicate by hash

Cross-Links

• Model Compatibility for what happens after import.
• Model Registry for registration details.
• Artifact Registry for ArtifactStore semantics.