Fix Durable Objects TTL example where long TTLs lead to infinite alar…

[joshthoward]

…m invocations

Summary

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Documentation checklist

• The documentation style guide has been adhered to.
• If a larger change - such as adding a new page- an issue has been opened in relation to any incorrect or out of date information that this PR fixes.
• Files which have changed name or location have been allocated redirects.

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PR Change Summary

Updated the Durable Objects TTL example to clarify the correct implementation of Time To Live (TTL) and prevent infinite alarm invocations.

• Clarified the implementation of TTL in Durable Objects to avoid infinite alarm invocations.
• Added a caution note regarding the use of the constructor for extending TTL.
• Updated comments in the code to reflect the correct behavior of TTL extension.

Modified Files

• src/content/docs/durable-objects/examples/durable-object-ttl.mdx

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[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
/src/content/docs/durable-objects/	@elithrar, @vy-ton, @joshthoward, @oxyjun, @harshil1712, @cloudflare/pcx-technical-writing

[github-actions]

Preview URL: https://36fb1fc0.preview.developers.cloudflare.com
Preview Branch URL: https://joshthoward-do-ttl-example.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/durable-objects/examples/durable-object-ttl/	https://joshthoward-do-ttl-example.preview.developers.cloudflare.com/durable-objects/examples/durable-object-ttl/

[vy-ton]

Why does the title say not available in local dev?

[Frederik-Baetens]

I think alarm support in local dev is limited/non-existent.

[joshthoward]

This was a copy/paste error. Thank you for catching @vy-ton.

[vy-ton]

@Oxyjun as a separate task, can we also enhance the alarm docs with:

• warns against calling .setAlarm() in the constructor, at least without checking that the alarm is not already set
• clarify recommendation is because if DO is inactive then the constructor is invoked before the alarm handler. So if the constructor code calls setAlarm, then it could interfere with the already configured next alarm

[Oxyjun]

@Oxyjun as a separate task, can we also enhance the alarm docs with:

• warns against calling .setAlarm() in the constructor, at least without checking that the alarm is not already set
• clarify recommendation is because if DO is inactive then the constructor is invoked before the alarm handler. So if the constructor code calls setAlarm, then it could interfere with the already configured next alarm

Tracking this here: #22746

[joshthoward]

This PR is replaced by #22761 because of the new security rules for our GitHub account.