fix(lambda): copy func code to /var/runtime for provided runtimes #114 (#39)

Author: hectorvent

sdk-test-java/src/main/java/com/floci/test/tests/LambdaInvokeTests.java

@@ -145,6 +145,50 @@ public void run(TestContext ctx) {
                 lambda.deleteFunction(DeleteFunctionRequest.builder()
                         .functionName(rubyFn).build());
             } catch (Exception ignored) {}
+
+            // provided.al2023 custom runtime (bootstrap shell script)
+            String providedFn = "sdk-invoke-provided-fn";
+            try {
+                lambda.createFunction(CreateFunctionRequest.builder()
+                        .functionName(providedFn)
+                        .runtime(Runtime.PROVIDED_AL2023)
+                        .role(role)
+                        .handler("bootstrap")
+                        .timeout(30)
+                        .memorySize(256)
+                        .code(FunctionCode.builder()
+                                .zipFile(SdkBytes.fromByteArray(LambdaUtils.providedRuntimeZip()))
+                                .build())
+                        .build());
+                ctx.check("Lambda provided.al2023 Invoke: CreateFunction", true);
+            } catch (Exception e) {
+                ctx.check("Lambda provided.al2023 Invoke: CreateFunction", false, e);
+                return;
+            }
+
+            try {
+                System.out.println("  (provided.al2023 cold start — waiting for container...)");
+                InvokeResponse resp = lambda.invoke(InvokeRequest.builder()
+                        .functionName(providedFn)
+                        .invocationType(InvocationType.REQUEST_RESPONSE)
+                        .payload(SdkBytes.fromUtf8String("{}"))
+                        .build());
+
+                String payload = resp.payload().asUtf8String();
+                System.out.println("  provided.al2023 response payload: " + payload);
+
+                boolean ok = resp.statusCode() == 200
+                        && resp.functionError() == null
+                        && payload.contains("hello from provided runtime");
+                ctx.check("Lambda provided.al2023 Invoke: RequestResponse", ok);
+            } catch (Exception e) {
+                ctx.check("Lambda provided.al2023 Invoke: RequestResponse", false, e);
+            }
+
+            try {
+                lambda.deleteFunction(DeleteFunctionRequest.builder()
+                        .functionName(providedFn).build());
+            } catch (Exception ignored) {}
         }
     }
 }

sdk-test-java/src/main/java/com/floci/test/tests/LambdaUtils.java

@@ -58,6 +58,39 @@ def lambda_handler(event:, context:)
         }
     }
 
+    /**
+     * ZIP containing a {@code bootstrap} shell script that implements the Lambda Runtime API.
+     * Used to test {@code provided.al2023} / {@code provided.al2} custom runtimes.
+     * The script calls {@code /invocation/next}, then posts {@code "hello from provided runtime"}
+     * as the response.
+     */
+    public static byte[] providedRuntimeZip() {
+        String bootstrap = """
+                #!/bin/sh
+                ENDPOINT="http://${AWS_LAMBDA_RUNTIME_API}/2018-06-01/runtime"
+                while true; do
+                  HEADERS=$(mktemp)
+                  curl -sS -D "$HEADERS" -o /tmp/event.json "${ENDPOINT}/invocation/next"
+                  REQUEST_ID=$(grep -i 'lambda-runtime-aws-request-id' "$HEADERS" | tr -d '\\r' | awk '{print $2}')
+                  curl -sS -X POST "${ENDPOINT}/invocation/${REQUEST_ID}/response" \\
+                    -H 'Content-Type: application/json' \\
+                    -d '"hello from provided runtime"'
+                  rm -f "$HEADERS"
+                done
+                """;
+        try {
+            var baos = new java.io.ByteArrayOutputStream();
+            try (var zos = new java.util.zip.ZipOutputStream(baos)) {
+                zos.putNextEntry(new java.util.zip.ZipEntry("bootstrap"));
+                zos.write(bootstrap.getBytes(StandardCharsets.UTF_8));
+                zos.closeEntry();
+            }
+            return baos.toByteArray();
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to build provided-runtime bootstrap ZIP", e);
+        }
+    }
+
     /**
      * Minimal valid ZIP containing a stub {@code index.js} — accepted by the emulator
      * without needing a real runtime.