- Checkpoint: 1st draft

ApiAggregator.sln

@@ -5,17 +5,13 @@ VisualStudioVersion = 17.9.34723.18
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{4338FF70-3C81-4370-ACFB-00E14545BA99}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ApiAggregator.Net", "src\ApiAggregator\ApiAggregator.Net.csproj", "{8250784C-5415-47C2-9FE4-9E54FA4672B6}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ApiAggregator.Net", "src\ApiAggregator\ApiAggregator.Net.csproj", "{8250784C-5415-47C2-9FE4-9E54FA4672B6}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "tests", "tests", "{31E7A02C-167D-46FB-A90A-F3995FD5682D}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ApiAggregator.Tests", "tests\ApiAggregator.Tests\ApiAggregator.Tests.csproj", "{C9ED08F3-F754-4D7A-8034-8FC180EA7F7A}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ApiAggregator.Tests", "tests\ApiAggregator.Tests\ApiAggregator.Tests.csproj", "{C9ED08F3-F754-4D7A-8034-8FC180EA7F7A}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "misc", "misc", "{D6340772-5767-4604-9E64-04078C0C2CAC}"
-	ProjectSection(SolutionItems) = preProject
-		LICENSE = LICENSE
-		README.md = README.md
-	EndProjectSection
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "github", "github", "{BCE2D3FE-6CF1-4932-9DEE-5B761A132C5E}"
 	ProjectSection(SolutionItems) = preProject

README.md

@@ -12,7 +12,6 @@
 #### Extends `Schemio` for APIs
 ApiAggregator uses `Schemio` to extend support for apis to configure hierarchical graph of `query`/`transformer` pairs to return aggregated data in a single response.
 > You can read on [Schemio](https://github.com/CodeShayk/Schemio) for more details on the core functionality. 
-
 Please see appendix for schemio implementation in ApiAggregator.
 
 

src/ApiAggregator/ApiAggregator.Net.csproj

@@ -16,21 +16,31 @@
     <PackageTags>api, aggregator, api-aggregator, utility, api-utility, data-aggregator, api-response, api-response-aggregator</PackageTags>
     <IncludeSymbols>True</IncludeSymbols>
     <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+    <PackageLicenseFile>LICENSE</PackageLicenseFile>
   </PropertyGroup>
 
   <ItemGroup>
-    <None Include="..\..\Images\ninja-icon-16.png">
+    <None Include="..\..\Images\ninja-icon-16.png" Link="misc\ninja-icon-16.png">
       <Pack>True</Pack>
       <PackagePath>\</PackagePath>
     </None>
-    <None Include="..\..\README.md">
+    <None Include="..\..\LICENSE" Link="misc\LICENSE">
+      <Pack>True</Pack>
+      <PackagePath>\</PackagePath>
+    </None>
+    <None Include="..\..\README.md" Link="misc\README.md">
       <Pack>True</Pack>
       <PackagePath>\</PackagePath>
     </None>
   </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Http" Version="8.0.1" />
     <PackageReference Include="Schemio.Core" Version="1.0.0" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Folder Include="misc\" />
+  </ItemGroup>
+
 </Project>

src/ApiAggregator/BaseWebQuery.cs

@@ -0,0 +1,157 @@
+using Microsoft.Extensions.Logging;
+using System.Text.Json;
+using Schemio;
+
+namespace ApiAggregator
+{
+    /// <summary>
+    /// Implement to create a Web query using api endpoint.
+    /// </summary>
+    /// <typeparam name="TParameter">Type of Query parameter</typeparam>
+    /// <typeparam name="TResult">Type of Query Result</typeparam>
+    public abstract class BaseWebQuery<TParameter, TResult> : BaseQuery<TParameter, TResult>, IWebQuery, IRootQuery, IChildQuery
+       where TParameter : IQueryParameter where TResult : IQueryResult
+    {
+        protected BaseWebQuery(string baseAddress)
+        {
+            BaseAddress = baseAddress;
+            Url = GetUrl(QueryParameter);
+            Headers = GetHeaders();
+        }
+
+        /// <summary>
+        /// List of Request headers for the api call.
+        /// </summary>
+        public List<KeyValuePair<string, string>> Headers { get; protected set; }
+
+        /// <summary>
+        /// Base address for the api call.
+        /// </summary>
+        public string BaseAddress { get; protected set; }
+
+        /// <summary>
+        /// Api endpoint - complete or relative.
+        /// </summary>
+        public string Url { get; protected set; }
+
+        /// <summary>
+        /// Override to pass custom headers with the api request.
+        /// </summary>
+        /// <returns></returns>
+        protected virtual List<KeyValuePair<string, string>>? GetHeaders()
+        { return []; }
+
+        /// <summary>
+        /// Implement to construct the api endpoint.
+        /// </summary>
+        /// <param name="queryParameter">Query Parameter</param>
+        /// <returns></returns>
+        protected abstract string? GetUrl(TParameter queryParameter);
+
+        /// <summary>
+        /// Implement to resolve query parameter.
+        /// </summary>
+        /// <param name="context">root context.</param>
+        /// <param name="parentQueryResult">query result from parent query (when configured as nested query). Can be null.</param>
+        protected abstract void ResolveQueryParameter(IDataContext context, IQueryResult parentQueryResult);
+
+        /// <summary>
+        /// Implement to resolve query parameter for nested queries
+        /// </summary>
+        /// <param name="context">root context</param>
+        /// <param name="parentQueryResult">query result from parent query.</param>
+        public void ResolveChildQueryParameter(IDataContext context, IQueryResult parentQueryResult)
+        {
+            ResolveQueryParameter(context, parentQueryResult);
+        }
+
+        /// <summary>
+        /// Implement to resolve query parameter for first level queries.
+        /// </summary>
+        /// <param name="context">root context</param>
+        public void ResolveRootQueryParameter(IDataContext context)
+        {
+            ResolveQueryParameter(context, null);
+        }
+
+        /// <summary>
+        /// Run this web query to get results.
+        /// </summary>
+        /// <param name="httpClientFactory">HttpClientFactory</param>
+        /// <param name="logger">Logger</param>
+        /// <returns></returns>
+        /// <exception cref="ArgumentNullException">when httpclientfactory is null.</exception>
+        public virtual async Task<IQueryResult[]> Run(IHttpClientFactory httpClientFactory, ILogger logger)
+        {
+            if (httpClientFactory == null)
+                throw new ArgumentNullException("HttpClientFactory is required");
+
+            var localStorage = new List<TResult>();
+
+            logger?.LogInformation($"Run query: {GetType().Name}");
+
+            using (var client = httpClientFactory.CreateClient())
+            {
+                logger?.LogInformation($"Executing web queries on thread {Thread.CurrentThread.ManagedThreadId} (task {Task.CurrentId})");
+
+                try
+                {
+                    HttpResponseMessage result;
+
+                    try
+                    {
+                        if (!string.IsNullOrEmpty(BaseAddress))
+                            client.BaseAddress = new Uri(BaseAddress);
+
+                        if (Headers != null && Headers.Any())
+                            foreach (var header in Headers)
+                                client.DefaultRequestHeaders.Add(header.Key, header.Value);
+
+                        result = await client.GetAsync(Url);
+
+                        if (!result.IsSuccessStatusCode)
+                        {
+                            logger?.LogInformation($"Result of executing web query {Url} is not success status code");
+                        }
+
+                        var raw = result.Content.ReadAsStringAsync().Result;
+
+                        if (string.IsNullOrWhiteSpace(raw))
+                            logger?.LogInformation($"Result.Content of executing web query {Url} is null or whitespace");
+
+                        if (ResultType.IsArray)
+                        {
+                            var arrObject = JsonSerializer.Deserialize(raw, ResultType);
+                            if (arrObject != null)
+                                localStorage.AddRange((IEnumerable<TResult>)arrObject);
+                        }
+                        else
+                        {
+                            var obj = JsonSerializer.Deserialize(raw, ResultType);
+                            if (obj != null)
+                                localStorage.Add((TResult)obj);
+                        }
+                    }
+                    catch (TaskCanceledException ex)
+                    {
+                        logger?.LogWarning(ex, $"An error occurred while sending the request. Query URL: {Url}");
+                    }
+                    catch (HttpRequestException ex)
+                    {
+                        logger?.LogWarning(ex, $"An error occurred while sending the request. Query URL: {Url}");
+                    }
+                }
+                catch (AggregateException ex)
+                {
+                    logger?.LogInformation($"Web query {GetType().Name} failed");
+                    foreach (var e in ex.InnerExceptions)
+                    {
+                        logger?.LogError(e, "");
+                    }
+                }
+            }
+
+            return localStorage.Cast<IQueryResult>().ToArray();
+        }
+    }
+}

src/ApiAggregator/ColonSeparatedMatcher.cs

@@ -0,0 +1,13 @@
+using Schemio;
+using Schemio.Helpers;
+
+namespace ApiAggregator
+{
+    public class ColonSeparatedMatcher : ISchemaPathMatcher
+    {
+        public bool IsMatch(string inputXPath, ISchemaPaths configuredXPaths) =>
+              // Does the template xpath contain any of the mapping xpaths?
+              inputXPath.IsNotNullOrEmpty()
+              && configuredXPaths.Paths.Any(x => inputXPath.ToLower().Contains(x.ToLower()));
+    }
+}

src/ApiAggregator/EnumerableExtensions.cs

@@ -0,0 +1,13 @@
+using Schemio;
+
+namespace ApiAggregator
+{
+    public static class EnumerableExtensions
+    {
+        public static IEnumerable<T> GetByType<T>(this IEnumerable<IQuery> list) where T : class, IQuery
+        {
+            var filtered = list.Where(q => (q as T) != null);
+            return filtered.Cast<T>();
+        }
+    }
+}

src/ApiAggregator/IWebQuery.cs

@@ -0,0 +1,14 @@
+using Microsoft.Extensions.Logging;
+using Schemio;
+
+namespace ApiAggregator
+{
+    public interface IWebQuery : IQuery
+    {
+        List<KeyValuePair<string, string>> Headers { get; }
+        string BaseAddress { get; }
+        string Url { get; }
+
+        Task<IQueryResult[]> Run(IHttpClientFactory httpClientFactory, ILogger logger);
+    }
+}

src/ApiAggregator/QueryEngine.cs

@@ -0,0 +1,47 @@
+using Microsoft.Extensions.Logging;
+using Schemio;
+
+namespace ApiAggregator
+{
+    public class QueryEngine : IQueryEngine
+    {
+        private readonly ILogger<QueryEngine> logger;
+        private readonly IHttpClientFactory httpClientFactory;
+
+        public QueryEngine(IHttpClientFactory httpClientFactory, ILogger<QueryEngine> logger)
+        {
+            this.httpClientFactory = httpClientFactory;
+            this.logger = logger;
+        }
+
+        public bool CanExecute(IQuery query) => query is IWebQuery;
+
+        public IEnumerable<IQueryResult> Execute(IEnumerable<IQuery> queries)
+        {
+            if (queries == null || !queries.Any())
+                return [];
+
+            var webQueries = queries.GetByType<IWebQuery>();
+
+            if (!webQueries.Any())
+                return [];
+
+            logger.LogInformation($"Total web queries to execute: {webQueries.Count()}");
+
+            var tasks = webQueries
+                .Select(q => q.Run(httpClientFactory, logger))
+                .ToArray();
+
+            Task.WhenAll(tasks);
+
+            var result = new List<IQueryResult>();
+
+            foreach (var task in tasks)
+            {
+                result.AddRange(task.Result);
+            }
+
+            return result.ToArray();
+        }
+    }
+}

src/ApiAggregator/ServicesExtensions.cs

@@ -0,0 +1,36 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using Schemio;
+using Schemio.Impl;
+
+namespace ApiAggregator
+{
+    public static class ServicesExtensions
+    {
+        public static IServiceCollection UseApiAggregator(this IServiceCollection services, Func<IEntity, IEntitySchema<IEntity>> schemas)
+        {
+            services.AddTransient(typeof(IQueryBuilder<>), typeof(QueryBuilder<>));
+            services.AddTransient(typeof(ITransformExecutor<>), typeof(TransformExecutor<>));
+            services.AddTransient(typeof(IDataProvider<>), typeof(DataProvider<>));
+            //services.AddTransient(typeof(IEntitySchema<>), typeof(BaseEntitySchema<>));
+
+            services.AddTransient<IQueryExecutor, QueryExecutor>();
+            services.AddTransient<ISchemaPathMatcher, ColonSeparatedMatcher>();
+            services.AddTransient<IQueryEngine, QueryEngine>();
+
+            //services.AddTransient((c) => schema);
+
+            return services;
+        }
+
+        public static IServiceCollection AddEntitySchema<TEntity>(this IServiceCollection services, IEntitySchema<IEntity> schema)
+            where TEntity : IEntity
+        {
+            if (schema != null)
+                services.AddTransient(c => (IEntitySchema<TEntity>)schema);
+
+            return services;
+        }
+    }
+}