refactor(web): authoritative Content-Length, typed Optional<AppVersion> in controller

cameleer-server-app/src/main/java/com/cameleer/server/app/security/SecurityBeanConfig.java

@@ -2,7 +2,6 @@ package com.cameleer.server.app.security;
 
 import com.cameleer.server.app.web.ArtifactDownloadTokenSigner;
 import org.springframework.beans.factory.InitializingBean;
-import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -39,9 +38,8 @@ public class SecurityBeanConfig {
     }
 
     @Bean
-    public ArtifactDownloadTokenSigner artifactDownloadTokenSigner(
+    public ArtifactDownloadTokenSigner artifactDownloadTokenSigner(SecurityProperties properties) {
-            @Value("${cameleer.server.security.jwtsecret}") String jwtSecret) {
+        return new ArtifactDownloadTokenSigner(properties.getJwtSecret(), Clock.systemUTC());
-        return new ArtifactDownloadTokenSigner(jwtSecret, Clock.systemUTC());
     }
 
     @Bean

cameleer-server-app/src/main/java/com/cameleer/server/app/storage/FilesystemArtifactStore.java

@@ -43,6 +43,11 @@ public class FilesystemArtifactStore implements ArtifactStore {
         return Files.newInputStream(pathOf(coords));
     }
 
+    @Override
+    public long size(ArtifactCoordinates coords) throws IOException {
+        return Files.size(pathOf(coords));
+    }
+
     @Override
     public boolean exists(ArtifactCoordinates coords) {
         return Files.exists(pathOf(coords));

cameleer-server-app/src/main/java/com/cameleer/server/app/web/ArtifactDownloadController.java

@@ -2,6 +2,7 @@ package com.cameleer.server.app.web;
 
 import com.cameleer.server.core.runtime.AppService;
 import com.cameleer.server.core.runtime.AppVersion;
+import com.cameleer.server.core.storage.ArtifactCoordinates;
 import com.cameleer.server.core.storage.ArtifactStore;
 import org.springframework.core.io.InputStreamResource;
 import org.springframework.http.MediaType;
@@ -14,6 +15,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.Optional;
 import java.util.UUID;
 
 /**
@@ -44,16 +46,17 @@ public class ArtifactDownloadController {
         if (!signer.verify(appVersionId, exp, sig)) {
             return ResponseEntity.status(401).build();
         }
-        AppVersion version;
+        Optional<AppVersion> versionOpt = appService.findVersion(appVersionId);
-        try {
+        if (versionOpt.isEmpty()) {
-            version = appService.getVersion(appVersionId);
-        } catch (IllegalArgumentException e) {
             return ResponseEntity.notFound().build();
         }
-        InputStream in = artifactStore.get(appService.coordinatesFor(version));
+        AppVersion version = versionOpt.get();
+        ArtifactCoordinates coords = appService.coordinatesFor(version);
+        long size = artifactStore.size(coords);
+        InputStream in = artifactStore.get(coords);
         return ResponseEntity.ok()
                 .contentType(MediaType.parseMediaType("application/java-archive"))
-                .contentLength(version.jarSizeBytes())
+                .contentLength(size)
                 .body(new InputStreamResource(in));
     }
 }

cameleer-server-app/src/test/java/com/cameleer/server/app/storage/FilesystemArtifactStoreTest.java

@@ -72,6 +72,15 @@ class FilesystemArtifactStoreTest {
         }
     }
 
+    @Test
+    void sizeReturnsActualOnDiskBytes(@TempDir Path tmp) throws Exception {
+        FilesystemArtifactStore store = new FilesystemArtifactStore(tmp.toString());
+        ArtifactCoordinates c = new ArtifactCoordinates("default", UUID.randomUUID(), 1);
+        byte[] payload = new byte[1234];
+        store.put(c, new java.io.ByteArrayInputStream(payload), payload.length);
+        assertThat(store.size(c)).isEqualTo(1234L);
+    }
+
     @Test
     void deleteLeavesAppDirAloneWhenSiblingVersionExists(@TempDir Path tmp) throws Exception {
         FilesystemArtifactStore store = new FilesystemArtifactStore(tmp.toString());

cameleer-server-app/src/test/java/com/cameleer/server/app/web/ArtifactDownloadControllerTest.java

@@ -10,6 +10,7 @@ import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 
 import java.io.ByteArrayInputStream;
+import java.util.Optional;
 import java.util.UUID;
 
 import static org.mockito.ArgumentMatchers.any;
@@ -54,8 +55,9 @@ class ArtifactDownloadControllerTest {
         UUID id = UUID.randomUUID();
         when(signer.verify(eq(id), eq(123L), eq("good"))).thenReturn(true);
         AppVersion v = new AppVersion(id, UUID.randomUUID(), 1, "loc", "h", "a.jar", 5L, null, null, null);
-        when(appService.getVersion(id)).thenReturn(v);
+        when(appService.findVersion(id)).thenReturn(Optional.of(v));
         when(appService.coordinatesFor(v)).thenReturn(new ArtifactCoordinates("default", v.appId(), 1));
+        when(artifactStore.size(any())).thenReturn(5L);
         when(artifactStore.get(any())).thenReturn(new ByteArrayInputStream("hello".getBytes()));
 
         mvc.perform(get("/api/v1/artifacts/{id}", id).param("exp", "123").param("sig", "good"))
@@ -73,14 +75,14 @@ class ArtifactDownloadControllerTest {
                 .andExpect(status().isUnauthorized());
 
         // Defence-in-depth: bad sig must short-circuit before any data lookup.
-        verify(appService, never()).getVersion(any());
+        verify(appService, never()).findVersion(any());
     }
 
     @Test
     void returns404WhenArtifactMissing() throws Exception {
         UUID id = UUID.randomUUID();
         when(signer.verify(any(), anyLong(), any())).thenReturn(true);
-        when(appService.getVersion(id)).thenThrow(new IllegalArgumentException("AppVersion not found"));
+        when(appService.findVersion(id)).thenReturn(Optional.empty());
 
         mvc.perform(get("/api/v1/artifacts/{id}", id).param("exp", "123").param("sig", "ok"))
                 .andExpect(status().isNotFound());

cameleer-server-core/src/main/java/com/cameleer/server/core/runtime/AppService.java

@@ -13,6 +13,7 @@ import java.security.MessageDigest;
 import java.util.HexFormat;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.UUID;
 import java.util.regex.Pattern;
 
@@ -57,6 +58,13 @@ public class AppService {
                 .orElseThrow(() -> new IllegalArgumentException("AppVersion not found: " + versionId));
     }
 
+    /** Typed Optional accessor for callers that distinguish missing-rows from
+     * other failures without relying on the message-based exception convention
+     * of {@link #getVersion(UUID)}. */
+    public Optional<AppVersion> findVersion(UUID versionId) {
+        return versionRepo.findById(versionId);
+    }
+
     /** Coordinate corresponding to an AppVersion. Used by callers that need to
      *  pass the artifact identity to {@link ArtifactStore} (download, delete, exists). */
     public ArtifactCoordinates coordinatesFor(AppVersion version) {

cameleer-server-core/src/main/java/com/cameleer/server/core/storage/ArtifactStore.java

@@ -22,6 +22,11 @@ public interface ArtifactStore {
     /** Open the artifact for reading. Caller closes. */
     InputStream get(ArtifactCoordinates coords) throws IOException;
 
+    /** Size of the stored artifact in bytes. Authoritative — read from the backend
+     * at serve time so a stale {@code AppVersion.jarSizeBytes} cannot silently
+     * truncate downloads. */
+    long size(ArtifactCoordinates coords) throws IOException;
+
     /** True if an artifact is currently stored under {@code coords}. */
     boolean exists(ArtifactCoordinates coords);