[arv]

Documents three server mutator features from Zero 1.11. This is a draft until 1.11 ships.

Changes

contents/docs/mutators.mdx:

• Returning Data: replaces the "not yet supported" note and keeps the #returning-data anchor. Covers:
  • the client and server runs return separate values, read from data on .client and .server;
  • data is typed ReadonlyJSONValue;
  • the mutate handler must return the mutator's result;
  • the server value is stored with the mutation result, so a lost response still delivers it.
• Retrying Mutators: tx.retryOn(predicate). Covers:
  • the predicate receives (error, attempt) and can be async;
  • errors at COMMIT are included;
  • at most 5 runs per mutation per request;
  • tx can't be used inside the predicate;
  • only retry idempotent side effects;
  • a note on what a custom Database must do.
  • The 40001 example is stated only for node-postgres and postgres.js. Drizzle wraps driver errors, and I didn't confirm Prisma's error shape.

contents/docs/server-zql.mdx:

• Isolation Level: isolationLevel for each adapter (Drizzle, Kysely, Prisma, node-postgres, postgres.js). For zeroNodePg it is the fourth argument. The section links to retryOn() for serialization failures.

This was checked against the code at rocicorp/mono 22fa3c27e:

• RetryPredicate in zql/src/mutate/custom.ts;
• MAX_MUTATOR_RUNS and mutation-result storage in zero-server/src/process-mutations.ts;
• TransactionOptions and the adapter signatures, for example zeroNodePg(schema, pg, lc, options) in adapters/pg.ts;
• MutatorResultDetails in zero-client/src/client/custom.ts.

Notes

• assets/search-index.json is not regenerated, to avoid conflicts with the other 1.11 docs PRs. Regenerate it when merging.

Checks

prettier --check passes, both pages compile as MDX, and vitest run passes.

🤖 Generated with Claude Code

https://claude.ai/code/session_01RRckJnCeGsYg9nCJSxBgTJ

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[arv]

The Verify Signed Commit Authors check fails, but not because of what this PR changes. A cloud Claude Code session signed commit e73c6a9 with its own SSH key, which isn't in rocicorp/.github's allowed signers. A re-run won't fix it. To fix it, re-sign the commit with an allowed key:

git fetch origin arv/docs-1.11-mutators
git checkout arv/docs-1.11-mutators
git commit --amend --no-edit -S
git push --force-with-lease origin arv/docs-1.11-mutators

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[arv]

Folded into #325, which has all the 1.11 docs and the release notes in one PR. This commit is there unchanged.

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