From 202d5fd419ccfdfb6a7e5c408c9e77b672c8e904 Mon Sep 17 00:00:00 2001
From: Joel Scheuner <joel.scheuner.dev@gmail.com>
Date: Thu, 2 Jul 2026 14:54:46 +0200
Subject: [PATCH] docs(lambda): correct ESM behaviour coverage for
 ScalingConfig, ProvisionedPollerConfig, FunctionResponseTypes
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- ScalingConfig: SQS Standard/FIFO 🟠 → 🟡 (config accepted but poller
  count hard-coded / single-poller FIFO, not auto-scaled)
- ProvisionedPollerConfig: SQS Standard/FIFO ➖ → 🟡 (MinimumPollers
  honored; MaximumPollers / FIFO ignored)
- FunctionResponseTypes: MSK & Self-Managed ➖ → 🟠 (AWS supports
  ReportBatchItemFailures for Kafka; not implemented in LocalStack)
- Add footnotes [^3]/[^4] explaining the partial SQS behaviour

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 src/content/docs/aws/services/lambda.mdx | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/content/docs/aws/services/lambda.mdx b/src/content/docs/aws/services/lambda.mdx
index 22e86312..1c068bf8 100644
--- a/src/content/docs/aws/services/lambda.mdx
+++ b/src/content/docs/aws/services/lambda.mdx
@@ -290,8 +290,8 @@ import { Table, TableHeader, TableBody, TableHead, TableRow, TableCell } from '@
       <TableCell className="text-center">🟢</TableCell>
       <TableCell className="text-center">🟢</TableCell>
       <TableCell className="text-center">🟢</TableCell>
-      <TableCell className="text-center">➖</TableCell>
-      <TableCell className="text-center">➖</TableCell>
+      <TableCell className="text-center">🟠</TableCell>
+      <TableCell className="text-center">🟠</TableCell>
     </TableRow>
     <TableRow>
       <TableCell className="font-medium">BisectBatchOnFunctionError</TableCell>
@@ -305,9 +305,9 @@ import { Table, TableHeader, TableBody, TableHead, TableRow, TableCell } from '@
     </TableRow>
     <TableRow>
       <TableCell className="font-medium">ScalingConfig</TableCell>
-      <TableCell>The scaling configuration for the event source.</TableCell>
-      <TableCell className="text-center">🟠</TableCell>
-      <TableCell className="text-center">🟠</TableCell>
+      <TableCell>The scaling configuration for the event source. [^3]</TableCell>
+      <TableCell className="text-center">🟡</TableCell>
+      <TableCell className="text-center">🟡</TableCell>
       <TableCell className="text-center">➖</TableCell>
       <TableCell className="text-center">➖</TableCell>
       <TableCell className="text-center">➖</TableCell>
@@ -375,9 +375,9 @@ import { Table, TableHeader, TableBody, TableHead, TableRow, TableCell } from '@
     </TableRow>
     <TableRow>
       <TableCell className="font-medium">ProvisionedPollerConfig</TableCell>
-      <TableCell>Control throughput via min-max limits.</TableCell>
-      <TableCell className="text-center">➖</TableCell>
-      <TableCell className="text-center">➖</TableCell>
+      <TableCell>Control throughput via min-max limits. [^4]</TableCell>
+      <TableCell className="text-center">🟡</TableCell>
+      <TableCell className="text-center">🟡</TableCell>
       <TableCell className="text-center">➖</TableCell>
       <TableCell className="text-center">➖</TableCell>
       <TableCell className="text-center">🟠</TableCell>
@@ -428,6 +428,8 @@ import { Table, TableHeader, TableBody, TableHead, TableRow, TableCell } from '@
 
 [^1]: Read more at [Control which events Lambda sends to your function](https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventfiltering.html)
 [^2]: The available Metadata properties may not have full parity with AWS depending on the event source (read more at [Understanding event filtering basics](https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventfiltering.html#filtering-basics)).
+[^3]: For SQS Standard, `ScalingConfig` is accepted but not automatically applied — the poller count is currently hard-coded rather than scaled based on `MaximumConcurrency`. For SQS FIFO, a single poller is always used to preserve message-group ordering, so the scaling configuration is accepted but has no effect.
+[^4]: For SQS Standard, only `MinimumPollers` is honored (it sets the poller count); `MaximumPollers` has no effect. For SQS FIFO, the single-poller model means the configuration is accepted but ignored.
 
 Create a [GitHub Discussion](https://github.com/orgs/localstack/discussions/new/choose) or reach out to [LocalStack Support](/aws/help-support/get-help/) if you experience any challenges.