Better error handling for download endpoint

In e2e test, grab current machine.py version

.github/workflows/ci-e2e.yml

@@ -25,6 +25,13 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
+        # get version of machine.py - MACHINE_PY_IMAGE will force the docker compose to use the proper version of machine.py
+      - name: Install regctl
+        uses: iarekylew00t/regctl-installer@v1
+
+      - name: Getr Version of Machine.py
+        run: echo "MACHINE_PY_IMAGE=ghcr.io/sillsdev/machine.py:$(regctl image config ghcr.io/sillsdev/machine.py | jq -r ".config.Labels[\"org.opencontainers.image.version\"]")" >> $GITHUB_ENV
+
       - name: Setup .NET
         uses: actions/setup-dotnet@v3
         with:
@@ -58,6 +65,10 @@ jobs:
         if: ${{ failure() }}
         run: docker ps -a && docker logs --since 10m serval_cntr && docker logs --since 10m echo_cntr && docker logs --since 10m machine-engine-cntr && docker logs --since 10m serval-mongo-1 && docker logs --since 10m machine-job-cntr
 
-      - name: Stop containers
-        if: ${{ success() || failure() }}
+      - name: Stop containers branch
+        if: ${{ success() || failure() }} and steps.find_matching_branch.outcome != 'success'
         run: docker compose -f "../tmp/serval/docker-compose.yml" down
+
+      - name: Stop containers main
+        if: ${{ success() || failure() }} and steps.find_matching_branch.outcome == 'success'
+        run: docker compose -f "../serval/docker-compose.yml" down

src/SIL.Machine.AspNetCore/Services/NmtEngineService.cs

@@ -26,7 +26,6 @@ ISharedFileService sharedFileService
     private readonly ClearMLMonitorService _clearMLMonitorService = clearMLMonitorService;
     private readonly ILanguageTagService _languageTagService = languageTagService;
     private readonly ISharedFileService _sharedFileService = sharedFileService;
-
     public const string ModelDirectory = "models/";
 
     public static string GetModelPath(string engineId, int buildRevision)
@@ -137,9 +136,7 @@ public async Task<ModelDownloadUrl> GetModelDownloadUrlAsync(
         string filepath = GetModelPath(engineId, engine.BuildRevision);
         bool fileExists = await _sharedFileService.ExistsAsync(filepath, cancellationToken);
         if (!fileExists)
-            throw new FileNotFoundException(
-                $"The model should exist to be downloaded but is not there for BuildRevision {engine.BuildRevision}."
-            );
+            throw new FileNotFoundException($"The model for build revision , {engine.BuildRevision}, does not exist.");
         var expiresAt = DateTime.UtcNow.AddMinutes(MinutesToExpire);
         var modelInfo = new ModelDownloadUrl
         {

src/SIL.Machine.AspNetCore/Services/ServalTranslationEngineServiceV1.cs

@@ -150,6 +150,10 @@ ServerCallContext context
         {
             throw new RpcException(new Status(StatusCode.Aborted, e.Message));
         }
+        catch (FileNotFoundException e)
+        {
+            throw new RpcException(new Status(StatusCode.DataLoss, e.Message));
+        }
     }
 
     public override async Task<GetQueueSizeResponse> GetQueueSize(