Links
New projet
|
dotnet new webapi -o [project-name] --no-https
|
 |
On VS to not open the web brower when you start the application: right-click on the project → Properties → Debug → uncheck Launch browser |
| Controllers/ItemsController.cs
|
[ApiController]
[Produces("application/json")] // force le format JSON
[ApiVersion("1")] // need nuget package Microsoft.AspNetCore.Mvc.Versioning
[Route("[controller]")] // /item
public class ItemController : ControllerBase
{
private readonly IItemRepository itemRepository;
private readonly IMapper mapper;
public ItemsController(IItemRepository itemRepository, IMapper mapper)
{
this.itemRepository = itemRepository;
this.mapper = mapper;
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GET
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[HttpGet("{id:int}")]
[ProducesResponseType(typeof(ItemDto), StatusCodes.Status200OK)]
[ProducesResponseType(StatusCodes.Status400BadRequest)]
[ProducesResponseType(StatusCodes.Status404NotFound)]
public async Task<IActionResult> GetItemByIdAsync(int id, CancellationToken cancellationToken)
{
if (id <= 0)
{
return BadRequest("id must be greater than 0");
}
var item = await context.Items
.AsNoTracking()
.FirstOrDefaultAsync(x => x.Id == id, cancellationToken);
return transaction is null ? NotFound(id) : Ok(mapper.Map<ItemDto>(item));
}
[HttpGet]
[ProducesResponseType(typeof(IReadOnlyCollection<ItemDto>), StatusCodes.Status200OK)]
public async Task<IActionResult> GetAsync([FromQuery] ItemQuery query, CancellationToken cancellationToken)
{
var predicate = PredicateBuilder.New<Item>(true);
if (query.Name != default)
{
predicate = predicate.And(x => EF.Functions.Like(x.Name, $"%{query.Name}%"));
}
if (query.Ids != null && query.Ids.Count > 0)
{
predicate = predicate.And(x => query.Ids.Contains(x.Id));
}
var items = await context.Items
.Where(predicate)
.AsNoTracking()
.ToListAsync(cancellationToken);
return Ok(mapper.Map<IReadOnlyCollection<ItemDto>>(items));
}
// route: /[controller-route]/test
[HttpGet("test")]
public async Task<IActionResult> TestAsync() { }
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POST
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[HttpPost]
[ProducesResponseType(typeof(ItemDto), StatusCodes.Status201Created)]
public async Task<IActionResult> CreateItemAsync(CreateUpdateItemCommand command, CancellationToken cancellationToken)
{
var item = this.mapper.Map<Item>(command);
await context.AddAsync(item, cancellationToken);
await context.SaveChangesAsync(cancellationToken);
var response = this.mapper.Map<CreateItemResponse>(item);
return Created(HttpContext.Request.Path, response);
return Created($"https://localhost:5001/api/items/{createdItem.Id}", response);
return CreatedAtAction(nameof(Get), new { id = createdItem.Id }, response);
return CreatedAtRoute("api", new {
controller = "items",
action = nameof(Get),
id = $"{response.Id}"
}, response);
}
|
|
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[HttpPut("{id}")]
[ProducesResponseType(StatusCodes.Status204NoContent)]
[ProducesResponseType(StatusCodes.Status400BadRequest)]
[ProducesResponseType(StatusCodes.Status404NotFound)]
public async Task<IActionResult> UpdateAsync(int id, CreateUpdateItemCommand command)
{
if (id <= 0)
{
return BadRequest("id must be greater than 0");
}
var itemToUpdate = await context.Transactions.FirstOrDefaultAsync(x => x.Id == id, cancellationToken)
if (itemToUpdate == null)
{
return NotFound();
}
this.mapper.Map(command, itemToUpdate);
await context.SaveChangesAsync(cancellationToken);
return NoContent();
}
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DELETE
|
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[HttpDelete("{id:int}")]
[ProducesResponseType(StatusCodes.Status204NoContent)]
[ProducesResponseType(StatusCodes.Status400BadRequest)]
[ProducesResponseType(StatusCodes.Status404NotFound)]
public async Task<IActionResult> DeleteItemAsync(int id, CancellationToken cancellationToken)
{
if (id <= 0)
{
return BadRequest("id must be greater than 0.");
}
if (!await context.Transactions.AnyAsync(x => x.Id == id, cancellationToken))
{
return NotFound(id);
}
context.Remove(new Item { Id = id });
await context.SaveChangesAsync(cancellationToken);
return NoContent();
}
|
| Program.cs
|
var app = builder.Build();
if (app.Environment.IsDevelopment())
{
app.UseExceptionHandler("/error-development");
}
else
{
app.UseExceptionHandler("/error");
}
app.UseAuthorization();
|
| Controllers/ErrorController.cs
|
[ApiController]
public class ErrorController : ControllerBase
{
[Route("/error")]
[ApiExplorerSettings(IgnoreApi = true)]
public IActionResult HandleError() => Problem();
[Route("/error-development")]
[ApiExplorerSettings(IgnoreApi = true)]
public IActionResult HandleErrorDevelopment([FromServices] IHostEnvironment hostEnvironment)
{
if (!hostEnvironment.IsDevelopment())
{
return NotFound();
}
var exceptionHandlerFeature = HttpContext.Features.Get<IExceptionHandlerFeature>()!;
return Problem(
detail: exceptionHandlerFeature.Error.StackTrace,
title: GetFinalInnerException(exceptionHandlerFeature.Error).Message);
static Exception GetFinalInnerException(Exception exception)
=> exception.InnerException is null ? exception : GetFinalInnerException(exception.InnerException);
}
}
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Fluent Validation
|
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dotnet add package FluentValidation.AspNetCore
|
| Program.cs
|
builder.Services.AddControllers();
builder.Services.AddFluentValidationAutoValidation();
builder.Services.AddValidatorsFromAssemblyContaining<Program>();
|
| Validators/ItemValidator.cs
|
public class CreateItemQueryValidator : AbstractValidator<CreateItemQuery>
{
public CreateItemQueryValidator()
{
RuleFor(x => x.Name).NotEmpty();
|
Client
| Client/ItemClient.cs
|
public class ItemClient : IItemClient
{
private const string Path = "item";
private const string ApiVersion = "1";
private readonly HttpClient httpClient;
private readonly QueryBuilder queryBuilder;
// injection de HttpClient
public ItemDataService(HttpClient httpClient)
{
this.httpClient = httpClient;
queryBuilder = new QueryBuilder();
queryBuilder.Add("api-version", ApiVersion);
}
|
GET
ReadAsAsync
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public async Task<IReadOnlyList<ItemDto>> GetAllItemsAsync(CancellationToken cancellationToken)
{
var uri = new Uri($"{Path}{queryBuilder.ToQueryString()}", UriKind.Relative);
var response = await this.httpClient.GetAsync(uri, cancellationToken);
response.EnsureSuccessStatusCode();
var items = await response.Content.ReadAsAsync<IReadOnlyList<ItemDto>>(cancellationToken);
return items;
}
|
|
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dotnet add package Microsoft.AspNet.WebApi.Client
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JsonSerializer.DeserializeAsync
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public async Task<IReadOnlyList<ItemDto>> GetAllItemsAsync()
{
return await JsonSerializer.DeserializeAsync<IEnumerable<Item>>(
await _httpClient.GetStreamAsync("api/item"),
new JsonSerializerOptions()
{
PropertyNameCaseInsensitive = true
});
var response = await _httpClient.GetAsync("api/item");
if (!response.IsSuccessStatusCode)
throw new HttpRequestException(response.ReasonPhrase);
return await JsonSerializer.DeserializeAsync<IEnumerable<Item>>(
await response.Content.ReadAsStreamAsync(),
new JsonSerializerOptions()
{
PropertyNameCaseInsensitive = true
});
}
public async Task<Item> GetItemAsync(int itemId)
{
return await JsonSerializer.DeserializeAsync<Item>(
await _httpClient.GetStreamAsync($"api/item/{itemId}"),
new JsonSerializerOptions()
{
PropertyNameCaseInsensitive = true
});
var response = await _httpClient.GetAsync($"item/{itemId}");
if (!response.IsSuccessStatusCode)
throw new HttpRequestException(response.ReasonPhrase);
return await JsonSerializer.DeserializeAsync<Item>(
await response.Content.ReadAsStreamAsync());
}
|
POST
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public async Task<Item> AddItemAsync(Item item)
{
var itemJson =
new StringContent(JsonSerializer.Serialize(item), Encoding.UTF8, "application/json");
var response = await _httpClient.PostAsync("api/item", itemJson);
if (response.IsSuccessStatusCode)
{
return await JsonSerializer.DeserializeAsync<Item>(await response.Content.ReadAsStreamAsync());
}
return null;
}
|
PUT
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public async Task UpdateItemAsync(Item item)
{
var itemJson = new StringContent(JsonSerializer.Serialize(item), Encoding.UTF8, "application/json");
var response = await _httpClient.PutAsync("api/item", itemJson);
if (!response.IsSuccessStatusCode)
{
var validationProblem = await JsonSerializer.DeserializeAsync<ValidationProblemDetails>(
await response.Content.ReadAsStreamAsync());
// validationProblem.Errors: key = property, values = error list
}
}
|
DELETE
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public async Task DeleteItemAsync(int itemId)
{
var response = await _httpClient.DeleteAsync($"api/item/{itemId}");
if (!response.IsSuccessStatusCode)
{
var validationProblem = await JsonSerializer.DeserializeAsync<ValidationProblemDetails>(
await response.Content.ReadAsStreamAsync());
throw new HttpRequestException($"{validationProblem.Title}: {validationProblem.Detail}");
}
}
|
Query Strings
Url: http://localhost:80/api/items?ids=1,2&retrieveDeleted=true
| ItemClient.cs
|
var ids = new[] { 1, 2 };
var retrieveDeleted = true;
var queryBuilder = new QueryBuilder();
queryBuilder.Add(nameof(ids), string.Join(",", ids));
queryBuilder.Add(nameof(retrieveDeleted), retrieveDeleted.ToString());
var uri = new Uri($"{Path}{queryBuilder.ToQueryString()}", UriKind.Relative);
var response = await this.httpClient.GetAsync(uri);
|
| ItemController.cs
|
[HttpGet]
public IActionResult Get([FromQuery] IReadOnlyCollection<int> ids, [FromQuery] bool retrieveDeleted = false)
{ }
// FromQuery is required for IReadOnlyCollection<int> to avoid having 415 Unsupported Media Type
|
| ItemQuery.cs
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public class ItemQuery
{
public string Name { get; set; }
public int PageIndex { get; set; }
public int PageSize { get; set; }
}
|
| ItemClient.cs
|
public async Task<IReadOnlyCollection<ItemDto>> GetAsync()
{
var query = new ItemQuery {
ProfileName = string.Empty,
PageIndex = 0,
PageSize = 10
};
var uri = new Uri($"{Path}{query.ToQueryString()}", UriKind.Relative);
|
| ItemQueryExtension.cs
|
public static QueryString ToQueryString(this ItemQuery itemQuery)
{
var queryBuilder = new QueryBuilder();
queryBuilder.Add(nameof(itemQuery.ProfileName), itemQuery.Name);
queryBuilder.Add(nameof(itemQuery.PageIndex), itemQuery.PageIndex.ToString());
queryBuilder.Add(nameof(itemQuery.PageSize), itemQuery.PageSize.ToString());
return queryBuilder.ToQueryString();
}
|
| Startup.cs
|
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
app.UseStatusCodePagesWithReExecute("/error/{0}");
app.UseExceptionHandler("/error/500");
app.UseMvc();
|
|
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[HttpGet("/error/{code:int}")]
public string Error(int code)
{
return $"Error: {code}";
}
|
| OperationResult.cs
|
public sealed class OperationResult<TResult, TError>
{
public TResult Result { get; }
public TError Error { get; }
public bool Success => Error == null;
public OperationResult(TResult result)
{
Result = result;
}
public OperationResult(TError error)
{
Error = error;
}
}
|
|
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OperationResult<MyDto, MyError> result;
if (/*...*/)
{
result = new OperationResult<MyDto, MyError>(myError);
}
else
{
result = new OperationResult<MyDto, MyError>(myDto);
}
return result;
|
By default .NET Core 3.0 uses System.Text.Json.
Use Newtonsoft.Json
|
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dotnet add package Microsoft.AspNetCore.Mvc.NewtonsoftJson
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| Startup.cs
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public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
.AddNewtonsoftJson();
|
| Startup.cs
|
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers(options =>
{
options.ModelBinderProviders.Insert(0, new CommaSeparatedModelBinderProvider());
});
|
| CommaSeparatedModelBinderProvider.cs
|
public class CommaSeparatedModelBinderProvider : IModelBinderProvider
{
public IModelBinder GetBinder(ModelBinderProviderContext context)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
if (context.Metadata.ModelType.GetInterface(nameof(IEnumerable)) != null
&& context.Metadata.ModelType != typeof(string))
{
return new BinderTypeModelBinder(typeof(CommaSeparatedModelBinder));
}
return null;
}
}
|
| CommaSeparatedModelBinder.cs
|
public class CommaSeparatedModelBinder : IModelBinder
{
private static readonly MethodInfo ToArrayMethod = typeof(Enumerable).GetMethod("ToArray");
public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
var modelType = bindingContext.ModelType;
var modelName = bindingContext.ModelName;
var valueType = modelType.GetElementType() ?? modelType.GetGenericArguments().FirstOrDefault();
if (modelType.GetInterface(nameof(IEnumerable)) != null
&& valueType != null
&& valueType.GetInterface(nameof(IConvertible)) != null)
{
var valueProviderResult = bindingContext.ValueProvider.GetValue(modelName);
if (valueProviderResult == ValueProviderResult.None)
{
return Task.CompletedTask;
}
bindingContext.ModelState.SetModelValue(modelName, valueProviderResult);
var value = valueProviderResult.FirstValue;
// Check if the argument value is null or empty
if (string.IsNullOrEmpty(value))
{
return Task.CompletedTask;
}
var list = (IList)Activator.CreateInstance(typeof(List<>).MakeGenericType(valueType));
foreach (var splitValue in value.Split(new[] { ',' }))
{
if (!string.IsNullOrWhiteSpace(splitValue))
{
list.Add(Convert.ChangeType(splitValue, valueType));
}
}
var model = modelType.IsArray
? ToArrayMethod.MakeGenericMethod(valueType).Invoke(this, new[] { list })
: list;
bindingContext.Result = ModelBindingResult.Success(model);
}
return Task.CompletedTask;
}
}
|
Erreurs
Unsupported Media Type with Postman
- Body → raw = json à envoyer
- Headers → Content-Type = application/json
JsonSerializationException: Self referencing loop detected for property 'xxx' ...
| Startup.cs
|
services.AddMvc()
// ignorer les références circulaires entre objets dans EF pour JSON
.AddJsonOptions(opt => opt.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore);
|
SqlException: Cannot insert explicit value for identity column in table 'xxx' when IDENTITY_INSERT is set to OFF
Impossible de sauvegarder les changements si une entité a été insérée avec une valeur ≠ default dans une propriété bindée avec une colonne Identity.
Solution: forcer la valeur de cette propriété a default. La bdd mettra la valeur de la propriété a jour après avoir inséré l'entité.
