A conditional request asks whether a cached representation is still current. It can reduce repeated data transfer, but only when the endpoint and client agree on the validator and response behavior.
Do not invent an ETag from a title or assume every podcast API supports the same cache headers.
Preserve the server's validator
If the API documents an ETag or a last-modified validator, store it alongside the exact cached representation it describes. Send the corresponding conditional header on a later request according to the contract.
A 304 response does not contain a replacement body. Your client needs the earlier body to complete the operation. If the cache was cleared but the validator remains, the application may have nothing useful to display.
Keep variants separate. A response for another language, filter, or authorization context may need a different cache entry. Read the server's cache-control and variation rules instead of reusing a validator across unrelated requests.
Test the small state machine
Start without a cache. Fetch and store a representation and validator. Revalidate it unchanged, then change the fixture and fetch again. Finally, remove the cached body while leaving the validator to confirm that your recovery path works.
Handle the absence of conditional support gracefully. A normal bounded refresh schedule is better than attaching unsupported headers and assuming traffic has been saved.
Podnivo-specific cache behavior should come from its current documentation and responses. This guide describes the integration pattern, not a promise that every endpoint accepts conditional requests.
The benefit is a simpler freshness check for supported resources. It should not create a second set of assumptions that makes the cache harder to trust than a direct fetch.