Move HttpClient to CdpTableValue and update ADS hack (#2489)

HttpClient is now passed via InitAsync function and no more required in
RuntimeConfig
Removed tabular IR rewriter and related logic
Updated ADS hack with a new approach - ADS will be update in another PR
Tested live with no side effect

src/libraries/Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs

@@ -3,9 +3,10 @@
 
 using System;
 using System.Collections.Generic;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.PowerFx.Core.Entities;
+using Microsoft.PowerFx.Core.Entities; 
 using Microsoft.PowerFx.Core.IR;
 using Microsoft.PowerFx.Types;
 
@@ -21,33 +22,51 @@ public class CdpTableValue : TableValue, IRefreshable, IDelegatableTableValue
 
         protected internal readonly ConnectorType _connectorType;
 
+        private IReadOnlyCollection<DValue<RecordValue>> _cachedRows;
+
+        internal readonly HttpClient HttpClient;
+
         public RecordType TabularRecordType => _tabularService?.TabularRecordType;
 
         public CdpTableValue(CdpService tabularService, ConnectorType connectorType)
             : base(IRContext.NotInSource(new CdpTableType(tabularService.TableType)))
         {
             _tabularService = tabularService;
-            _connectorType = connectorType;           
+            _connectorType = connectorType;
+
+            HttpClient = tabularService.HttpClient;
         }
 
         internal CdpTableValue(IRContext irContext)
             : base(irContext)
         {
+            _cachedRows = null;
         }
 
-        public override IEnumerable<DValue<RecordValue>> Rows => throw new InvalidOperationException("No service context. Make sure to call engine.EnableTabularConnectors().");
-
-        public virtual void Refresh()
-        {
-        }
+        public override IEnumerable<DValue<RecordValue>> Rows => GetRowsAsync(null, null, CancellationToken.None).ConfigureAwait(false).GetAwaiter().GetResult();
 
         public async Task<IReadOnlyCollection<DValue<RecordValue>>> GetRowsAsync(IServiceProvider services, DelegationParameters parameters, CancellationToken cancel)
         {
-            var op = parameters.ToOdataParameters();
+            if (parameters == null && _cachedRows != null)
+            {
+                return _cachedRows;
+            }
+
+            var op = parameters?.ToOdataParameters();
             var rows = await _tabularService.GetItemsAsync(services, op, cancel).ConfigureAwait(false);
 
+            if (parameters == null)
+            {
+                _cachedRows = rows;
+            }
+
             return rows;
-        }        
+        }
+
+        public void Refresh()
+        {
+            _cachedRows = null;
+        }
     }   
 
     internal static class ODataParametersExtensions

src/libraries/Microsoft.PowerFx.Connectors/Tabular/Services/CdpService.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.PowerFx.Types;
@@ -23,6 +24,8 @@ public abstract class CdpService : CdpServiceBase
 
         public abstract ConnectorType ConnectorType { get; }
 
+        public abstract HttpClient HttpClient { get; }
+
         public virtual CdpTableValue GetTableValue()
         {
             return IsInitialized

src/libraries/Microsoft.PowerFx.Connectors/Tabular/Services/CdpTable.cs

@@ -22,6 +22,8 @@ public sealed class CdpTable : CdpService
 
         public string DatasetName { get; private set; }
 
+        public override HttpClient HttpClient => _httpClient;
+
         public override bool IsDelegable => TableCapabilities?.IsDelegable ?? false;
 
         public override ConnectorType ConnectorType => TabularTableDescriptor.ConnectorType;
@@ -34,6 +36,8 @@ public sealed class CdpTable : CdpService
 
         private string _uriPrefix;
 
+        private HttpClient _httpClient;
+
         public CdpTable(string dataset, string table)
         {
             DatasetName = dataset ?? throw new ArgumentNullException(nameof(dataset));
@@ -57,6 +61,8 @@ public async Task InitAsync(HttpClient httpClient, string uriPrefix, Cancellatio
                 throw new InvalidOperationException("TabularService already initialized");
             }
 
+            _httpClient = httpClient;
+
             // $$$ This is a hack to generate ADS
             bool adsHack = false;            
             if (uriPrefix.StartsWith("*", StringComparison.Ordinal))
@@ -99,16 +105,15 @@ protected override async Task<IReadOnlyCollection<DValue<RecordValue>>> GetItems
         {
             cancellationToken.ThrowIfCancellationRequested();
             ConnectorLogger executionLogger = serviceProvider?.GetService<ConnectorLogger>();
-            HttpClient httpClient = serviceProvider?.GetService<HttpClient>() ?? throw new InvalidOperationException("HttpClient is required on IServiceProvider");
-
+
             string queryParams = (odataParameters != null) ? "&" + odataParameters.ToQueryString() : string.Empty;
 
             Uri uri = new Uri(
                    (_uriPrefix ?? string.Empty) +
                    (_uriPrefix.Contains("/sql/") ? "/v2" : string.Empty) +
                    $"/datasets/{(DatasetMetadata.IsDoubleEncoding ? DoubleEncode(DatasetName) : DatasetName)}/tables/{HttpUtility.UrlEncode(TableName)}/items?api-version=2015-09-01" + queryParams, UriKind.Relative);
 
-            string text = await GetObject(httpClient, $"List items ({nameof(GetItemsInternalAsync)})", uri.ToString(), cancellationToken, executionLogger).ConfigureAwait(false);
+            string text = await GetObject(_httpClient, $"List items ({nameof(GetItemsInternalAsync)})", uri.ToString(), cancellationToken, executionLogger).ConfigureAwait(false);
             return !string.IsNullOrWhiteSpace(text) ? GetResult(text) : Array.Empty<DValue<RecordValue>>();
         }
 

src/tests/Microsoft.PowerFx.Connectors.Tests.Shared/FileTabularConnector.cs

@@ -5,7 +5,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
-using System.Text.RegularExpressions;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.PowerFx.Types;
@@ -46,23 +46,15 @@ public async Task FileTabularTest()
             PowerFxConfig config = new PowerFxConfig(Features.PowerFxV1);
             RecalcEngine engine = new RecalcEngine(config);
 
-#pragma warning disable CS0618 // Type or member is obsolete
-            engine.EnableTabularConnectors();
-#pragma warning restore CS0618 // Type or member is obsolete
-
             SymbolValues symbolValues = new SymbolValues().Add("File", fileTable);
 
             // Expression with tabular connector
             string expr = @"Last(FirstN(File, 2)).line";
 
             CheckResult check = engine.Check(expr, options: new ParserOptions() { AllowsSideEffects = true }, symbolTable: symbolValues.SymbolTable);
             Assert.True(check.IsSuccess);
-
-            // Confirm that InjectServiceProviderFunction has properly been added
-            string ir = new Regex("RuntimeValues_[0-9]+").Replace(check.PrintIR(), "RuntimeValues_XXX");
-            Assert.Equal("FieldAccess(Last:![line:s](FirstN:*[line:s](InjectServiceProviderFunction:*[line:s](ResolvedObject('File:RuntimeValues_XXX')), Float:n(2:w))), line)", ir);
-
-            // Use tabular connector. Internally we'll call ConnectorTableValueWithServiceProvider.GetRowsInternal to get the data
+
+            // Use tabular connector. Internally we'll call CdpTableValue.GetRowsInternal to get the data
             FormulaValue result = await check.GetEvaluator().EvalAsync(CancellationToken.None, symbolValues);
             StringValue str = Assert.IsType<StringValue>(result);
             Assert.Equal("b", str.Value);
@@ -85,6 +77,9 @@ public FileTabularService(string fileName)
 
         public override ConnectorType ConnectorType => null;
 
+        // No need for files
+        public override HttpClient HttpClient => null;
+
         // Initialization can be synchronous
         public void Init()
         {