Pulp

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Content Unit Creator - Downloads and creates objects

  - Process content units in slices to limit the number of in-memory objects

  - Determine which content units are already present in Pulp

  - For immediate download policy, determine which artifacts in a slice are already present in Pulp.

  - For immediate download policy, download all artifacts for each content unit. 

  - For immediate download policy, save new Content, Content Artifacts, Deferred Artifacts, and Artifacts to the db after downloading all artifacts.

  - For deferred download policy, save new Content, Content Artifacts, and Deferred Artifacts to the database.

  - Handle race conditions for db around writes to the database.

  - Transactional support around unit creation to ensure always creating a complete content unit or none

open questions: should this associate each unit as its made?

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Content Unit Downloader - Parallelized downloads, but it emits a content unit only when all files are downloaded

  - manages the asyncio loop for you

  - abstracts the collecting of downloads for a given content unit

  - driven by a simple loop

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Concurrent Downloader - Downloads any number of artifacts in parallel

  - provides digest and size validation

  - yields a file that is written to a temp area and all digests which were computed during download

  - you provide the asyncio loop

  - constrains the number of connections

  - share resources such as sessions,connection pools and auth tokens

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Synchronous Downloader - download a single file synchronously

  - blocking call so one download at a time

  - provides digest and size validation

  - yields a file that is written to a temp area and all digests which were computed during download

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