SCAL-322334: Add C# SDK full-stack demo

.gitignore

@@ -79,6 +79,9 @@ web_modules/
 .env.production.local
 .env.local
 
+# Allow the C# SDK demo backend env file to be checked in for convenience
+!rest-api/csharp-sdk/backend/.env
+
 # parcel-bundler cache (https://parceljs.org/)
 .cache
 .parcel-cache

rest-api/csharp-sdk/.devcontainer/devcontainer.json

@@ -0,0 +1,30 @@
+{
+  "name": "ThoughtSpot C# SDK demo",
+  "image": "mcr.microsoft.com/devcontainers/dotnet:1-8.0",
+  "features": {
+    "ghcr.io/devcontainers/features/node:1": {
+      "version": "20"
+    }
+  },
+  "workspaceFolder": "/workspaces/${localWorkspaceFolderBasename}/rest-api/csharp-sdk",
+  "postCreateCommand": "cd frontend && npm install",
+  "forwardPorts": [5000, 5173],
+  "portsAttributes": {
+    "5000": {
+      "label": "Backend (ASP.NET Core API)",
+      "onAutoForward": "notify"
+    },
+    "5173": {
+      "label": "Frontend (Vite)",
+      "onAutoForward": "openPreview"
+    }
+  },
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "ms-dotnettools.csharp",
+        "dbaeumer.vscode-eslint"
+      ]
+    }
+  }
+}

rest-api/csharp-sdk/README.md

@@ -0,0 +1,104 @@
+<!-- search-meta
+tags: [ThoughtSpot, C#, ASP.NET, Vite, React, backend, frontend, Codespaces]
+apis: [thoughtspot_rest_api_sdk, ASP.NET Core, Vite, React]
+questions:
+  - How do I connect a React frontend to an ASP.NET Core backend in GitHub Codespaces?
+  - How do I configure ThoughtSpot credentials for a C# SDK demo?
+  - How do I proxy Vite frontend requests to a local ASP.NET Core backend?
+  - How do I run a ThoughtSpot C# SDK full-stack demo in GitHub Codespaces?
+  - How do I use ThoughtSpot API with React and Vite?
+-->
+
+# ThoughtSpot C# SDK — full-stack demo
+
+[Open this repo in GitHub Codespaces](https://github.com/thoughtspot/developer-examples/codespaces/new?ref=SCAL-322334-add-csharp-developer-examples)
+
+A minimal two-process demo covering search users, search liveboards,
+exporting a liveboard's TML, and asking Spotter a natural-language question
+with a live streaming (SSE) answer.
+
+```
+backend/    ASP.NET Core minimal API (C#) wrapping the thoughtspot_rest_api_sdk package
+frontend/   Vite + React app that calls the backend
+```
+
+## Configure
+
+Both processes talk to the same cluster. Set these before running the backend
+(defaults point at the same demo cluster used elsewhere in this repo):
+
+```
+export TS_HOST=https://<your-cluster>
+export TS_USER=<username>
+export TS_PASS=<password>
+export TS_SPOTTER_WORKSHEET_ID=<worksheet-guid-with-AI-answer-generation-enabled>
+```
+
+Or set the `VITE_TS_HOST` / `VITE_TS_USERNAME` / `VITE_TS_PASSWORD` /
+`VITE_LIVEBOARD_ID` / `VITE_SPOTTER_WORKSHEET_ID` equivalents in
+`backend/.env` (loaded automatically at startup).
+
+### Why create-user / style-customization / PDF-export aren't here
+
+They all require admin privileges. On a restricted sandbox account (e.g. a
+training/trial cluster), those calls return a 403 "Operation is not allowed"
+— a cluster permission limit, not something this demo can route around — so
+they were dropped rather than shipped as broken buttons. Search users,
+search liveboards, TML export, and Spotter all work with a regular
+(non-admin) account, as long as `CAN_USE_SPOTTER` is granted for Spotter.
+
+The worksheet used for Spotter must have AI Answer Generation enabled
+(check the worksheet's metadata header — some sample worksheets ship with
+it disabled and Spotter returns "No answer found for your query" for them).
+
+## Run
+
+```bash
+# terminal 1
+cd backend
+dotnet run          # listens on http://localhost:5000
+
+# terminal 2
+cd frontend
+npm install
+npm run dev          # listens on http://localhost:5173
+```
+
+Open http://localhost:5173.
+
+## Notes
+
+- The backend authenticates via `ThoughtSpotRestApi.CreateAsync(new ApiClientConfiguration { ... })`
+  once at startup, rather than the legacy `HttpClient`/`HttpClientHandler`
+  constructors. `CreateAsync` builds its own `SocketsHttpHandler`/`HttpClient`
+  internally and is what actually gives you `ConnectTimeout`/`ReadTimeout`/
+  `WriteTimeout`, connection pooling, SSL handling, and automatic bearer-token
+  fetch + refresh. None of that is wired up if you construct the client from
+  your own `HttpClient`/`HttpClientHandler`.
+- CORS is locked to `http://localhost:5173` in `backend/Program.cs` — update
+  if you serve the frontend elsewhere.
+- TML export (`GET /api/liveboards/{id}/tml`) deserializes through
+  Newtonsoft.Json internally (that's what the SDK uses), so the backend
+  re-serializes the response with Newtonsoft before returning it — handing
+  the raw `List<Object>` straight to ASP.NET Core's default System.Text.Json
+  serializer silently produces near-empty `edoc`/`info` fields instead of an
+  error, since it doesn't know how to write out Newtonsoft's JToken types.
+- Spotter (`GET /api/spotter/stream`) creates a fresh agent conversation via
+  `CreateAgentConversation`, then relays
+  `SendAgentConversationMessageStreamingStreamAsync`'s Server-Sent Events
+  straight through to the browser as they arrive — the frontend consumes it
+  with a native `EventSource` (see `frontend/src/api.js`'s `streamSpotter`).
+  A custom `done` SSE event signals a clean finish and a custom `ts-error`
+  event carries backend/API errors; both close the connection to stop the
+  browser's default auto-reconnect behavior.
+  - **SDK workaround**: `thoughtspot_rest_api_sdk`'s `DataSourceContextInput`
+    model always serializes its unused sibling fields
+    (`data_source_identifiers`, `guid`) as explicit JSON `null`s — confirmed
+    still present as of `0.1.0-beta.7`. This cluster's request validation
+    rejects that shape (it falls back to expecting a `worksheet_context`
+    payload instead of `data_source_context`, and complains that its
+    `worksheet_ids` field is missing). The backend works around this by
+    leaving `ContextPayloadV2Input.DataSourceContext` unset and writing the
+    minimal `data_source_context` object via `AdditionalProperties` instead,
+    which avoids emitting the nulls. Worth retrying without the workaround on
+    newer SDK versions.

rest-api/csharp-sdk/backend/.env

@@ -0,0 +1,6 @@
+VITE_TS_HOST=https://training.thoughtspot.cloud
+VITE_TS_USERNAME=code-sandbox
+VITE_TS_PASSWORD=3mbed+#3xplz
+VITE_LIVEBOARD_ID=b504e160-3025-4508-a76a-1beb1f4b5eed
+# Worksheet with AI Answer Generation enabled, used by GET /api/spotter/stream
+VITE_SPOTTER_WORKSHEET_ID=cd252e5c-b552-49a8-821d-3eadaa049cca

rest-api/csharp-sdk/backend/.gitignore

@@ -0,0 +1,2 @@
+bin/
+obj/

rest-api/csharp-sdk/backend/Backend.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <RootNamespace>ThoughtSpotBackend</RootNamespace>
+    <!-- Only .NET 8 SDK is used to build, but let the app run against
+         whatever newer major runtime is actually installed on this machine
+         (e.g. 10.0.x), instead of failing because 8.0.x isn't present. -->
+    <RollForward>LatestMajor</RollForward>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <!-- Published SDK package: https://www.nuget.org/packages/thoughtspot_rest_api_sdk/0.1.0-beta.7 -->
+    <PackageReference Include="thoughtspot_rest_api_sdk" Version="0.1.0-beta.7" />
+  </ItemGroup>
+
+</Project>