What is Assembly Status?
Transloadit Assembly Status is the JSON representation of an Assembly. It includes the Assembly’s identifier, uploads, results, execution timing, and the information needed to locate result files.
How Assembly Status works
The status representation is the canonical snapshot of a processing job at the time it is produced. Transloadit uses this single format across Assembly creation responses, the status URL, and notification payloads, bringing together lifecycle state, timing, input records, Step outputs, errors, and result locations in one machine-readable document. Intermediate snapshots can change as branches finish, whereas terminal snapshots support durable result ingestion. A backend typically normalizes this document into its own job model and retains identifiers for support diagnostics.
Key facts
- 1Uploads and generated results are separate collections in the response, allowing clients to distinguish submitted source records from derivative files produced by Steps.
- 2Result entries are organized by Step name, so consumers should bind to the intended workflow branch rather than assume the first returned file is the desired asset.
- 3Polling clients need to recognize terminal success and failure states explicitly; the presence of partial metadata or some result files does not prove the whole graph succeeded.
When Assembly Status matters
Fetch it from the Assembly’s status URL to inspect completion, collect result URLs, or diagnose a failed Step. The same document is returned when an Assembly is created and delivered in Assembly Notifications. Do not treat an unfinished snapshot as final, and handle terminal failure states before consuming outputs.
Common use cases for platform workflows
These examples cover platform workflows broadly, not specifically Assembly Status.
- Running repeatable upload, import, processing, AI, storage, and notification pipelines.
- Tracking long-running media work independently from an application request.
- Referencing centrally stored credentials by name instead of sending storage secrets with each request.
Working with platform workflows
This guidance covers platform workflows broadly, not just Assembly Status.
A client authenticates and submits files or references together with workflow instructions. The platform validates the request, schedules dependent operations, records state transitions, and exposes results through a response, polling endpoint, or notification.
Platform concepts become reliable only when their lifecycle is explicit. Authentication, idempotency, retries, timeouts, observability, quotas, and terminal states should be designed together rather than added after failures occur.
What you gain
- Reusable workflows separate application intent from processing infrastructure.
- Stable job identifiers and lifecycle events improve observability and recovery.
- Managed queues and workers let products scale without embedding every media tool.
What it costs
- Synchronous responses are simple but keep connections open while long work executes.
- Aggressive retries improve recovery from transient faults but can duplicate work or overload a dependency.
- Higher concurrency reduces queue time until resource contention or a downstream limit becomes the bottleneck.
Before production
- 1Define authentication, authorization, idempotency, retries, and terminal error behavior.
- 2Observe queue time, execution time, callbacks, and partial results with stable identifiers.
- 3Exercise malformed, duplicate, interrupted, and unauthorized requests before launch.