Implements Pagination to a hardcoded limit in excess of the server ha…

…rd limit
specklesystems · Apr 22, 2023 · 06e61e2 · 06e61e2
1 parent 29950d8
commit 06e61e2
Show file tree

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Showing 2 changed files with 91 additions and 2 deletions.
diff --git a/Core/Core/Api/GraphQL/Client.GraphqlCleintOperations/Client.BranchOperations.cs b/Core/Core/Api/GraphQL/Client.GraphqlCleintOperations/Client.BranchOperations.cs
@@ -72,6 +72,71 @@ public async Task<List<Branch>> StreamGetBranches(
     var res = await ExecuteGraphQLRequest<StreamData>(request, cancellationToken).ConfigureAwait(false);
     return res.stream.branches.items;
   }
+/// <summary>
+  /// Get branches from a given stream
+  /// </summary>
+  /// <param name="streamId">Id of the stream to get the branches from</param>
+  /// <param name="branchesLimit">Max number of branches to retrieve</param>
+  /// <param name="commitsLimit">Max number of commits to retrieve</param>
+  /// <returns></returns>
+  public Task<Branches> PagedStreamGetBranches(string streamId, int branchesLimit = 10, int commitsLimit = 10, string? nextCursor = null)
+  {
+    return PagedStreamGetBranches(CancellationToken.None, streamId, branchesLimit, commitsLimit);
+  }
+
+  /// <summary>
+  /// Get paginated branches from a given stream
+  /// </summary>
+  /// <param name="cancellationToken"></param>
+  /// <param name="streamId">Id of the stream to get the branches from</param>
+  /// <param name="branchesLimit">Max number of branches to retrieve</param>
+  /// <param name="commitsLimit">Max number of commits to retrieve</param>
+  /// <param name="nextCursor">Cursor to get the next page of results</param>
+  /// <returns></returns>
+  /// <exception cref="Exception"></exception>
+  public async Task<Branches> PagedStreamGetBranches(
+    CancellationToken cancellationToken,
+    string streamId,
+    int branchesLimit = 10,
+    int commitsLimit = 10,
+    string? nextCursor = null
+  )
+  {
+    var request = new GraphQLRequest
+    {
+      Query =
+        $@"query Stream ($streamId: String!) {{
+                      stream(id: $streamId) {{
+                        branches(limit: {branchesLimit}, cursor: ""{nextCursor}"") {{
+                          cursor
+                          items {{
+                            id
+                            name
+                            description
+                            commits (limit: {commitsLimit}) {{
+                              totalCount
+                              cursor
+                              items {{
+                                id
+                                referencedObject
+                                sourceApplication
+                                message
+                                authorName
+                                authorId
+                                branchName
+                                parents
+                                createdAt
+                              }}
+                            }}
+                          }}
+                        }}                       
+                      }}
+                    }}",
+      Variables = new { streamId, nextCursor }
+    };
+    var res = await ExecuteGraphQLRequest<StreamData>(request, cancellationToken).ConfigureAwait(false);
+    return res.stream.branches;
+  }
 
   /// <summary>
   /// Creates a branch on a stream.

diff --git a/DesktopUI2/DesktopUI2/ViewModels/StreamViewModel.cs b/DesktopUI2/DesktopUI2/ViewModels/StreamViewModel.cs
@@ -220,6 +220,9 @@ public async Task GetStream()
     }
   }
 
+  /// The limit of branches to be displayed in the stream, Given a limit to prevent runaway Branch DOS attacks
+  private const int BranchLimit = 500;
+
   internal async void GetBranchesAndRestoreState()
   {
     try
@@ -246,7 +249,17 @@ internal async void GetBranchesAndRestoreState()
       AvailableFilters = new List<FilterViewModel>(Bindings.GetSelectionFilters().Select(x => new FilterViewModel(x)));
       SelectedFilter = AvailableFilters[0];
 
-      Branches = await Client.StreamGetBranches(Stream.id, 100, 0).ConfigureAwait(true);
+      // Get all branches created in the stream, not limited to the server limits
+      string nextCursor = null;
+      var branchCount = 0;
+
+      do
+      {
+        var branchResponse = await Client.PagedStreamGetBranches(Stream.id, 100, 0, nextCursor).ConfigureAwait(false);
+        Branches.AddRange(branchResponse.items);
+        nextCursor = branchResponse.cursor;
+        branchCount += branchResponse.items.Count;
+      } while (!string.IsNullOrEmpty(nextCursor) && branchCount <= BranchLimit);
 
       var index = Branches.FindIndex(x => x.name == StreamState.BranchName);
       if (index != -1)
@@ -408,7 +421,18 @@ private void UpdateStreamState()
   private async Task GetBranches()
   {
     var prevBranchName = SelectedBranch != null ? SelectedBranch.Branch.name : StreamState.BranchName;
-    Branches = await Client.StreamGetBranches(Stream.id, 100, 0).ConfigureAwait(true);
+
+    // Get all branches created in the stream, not limited to the server limits
+    string nextCursor = null;
+    var branchCount = 0;
+
+    do
+    {
+      var branchResponse = await Client.PagedStreamGetBranches(Stream.id, 100, 0, nextCursor).ConfigureAwait(false);
+      Branches.AddRange(branchResponse.items);
+      nextCursor = branchResponse.cursor;
+      branchCount += branchResponse.items.Count;
+    } while (!string.IsNullOrEmpty(nextCursor) && branchCount <= BranchLimit);
 
     var index = Branches.FindIndex(x => x.name == prevBranchName);
     if (index != -1)