refactor(lambda): extract CreateFunctionInput from create_function

[vieiralucas]

Summary

`create_function` was 118 lines, most of which were field extraction and defaulting for the `CreateFunction` request shape: `FunctionName`, `Runtime`, `Role`, `Handler`, `Description`, `Timeout`, `MemorySize`, `PackageType`, `Tags`, `Environment.Variables`, `Architectures`, and `Code.ZipFile` (base64-decoded). Only the last ~35 lines actually did anything: check for conflict, hash the code, build `LambdaFunction`, insert.

Move the parsing into `CreateFunctionInput::from_body`. The operation body now reads as 'parse input, check conflict, hash code, build function, persist' without the 80-line prelude. The `Code.ZipFile` base64 decode stays in `from_body` so `InvalidParameterValueException` is still surfaced at parse time.

Test plan

• `cargo fmt`
• `cargo clippy --workspace --all-targets -- -D warnings`
• `cargo test -p fakecloud-lambda` (8 passed)

---

Summary by cubic

Refactored Lambda function creation by extracting request parsing into CreateFunctionInput::from_body, making create_function smaller and easier to read. Invalid Code.ZipFile still fails fast with InvalidParameterValueException.

• Refactors
  • Moved field extraction and defaults (FunctionName, Runtime, Role, Handler, Description, Timeout, MemorySize, PackageType, Tags, Environment.Variables, Architectures, Code.ZipFile) into CreateFunctionInput.
  • Streamlined create_function flow: parse input → check conflict → hash code → build and persist LambdaFunction.
  • Code hash prefers decoded ZIP bytes; falls back to raw Code JSON for image-based functions.

^{Written for commit 4745889. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="crates/fakecloud-lambda/src/service.rs">

<violation number="1" location="crates/fakecloud-lambda/src/service.rs:192">
P2: `CreateFunction` now validates/decodes request payload before checking name conflict, which can return `InvalidParameterValueException` instead of `ResourceConflictException` for duplicate function names.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: CreateFunction now validates/decodes request payload before checking name conflict, which can return InvalidParameterValueException instead of ResourceConflictException for duplicate function names.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At crates/fakecloud-lambda/src/service.rs, line 192:

<comment>`CreateFunction` now validates/decodes request payload before checking name conflict, which can return `InvalidParameterValueException` instead of `ResourceConflictException` for duplicate function names.</comment>

<file context>
@@ -91,85 +189,21 @@ impl LambdaService {
-                )
-            })?
-            .to_string();
+        let input = CreateFunctionInput::from_body(&body)?;
 
         let mut state = self.state.write();
</file context>