public async Task <PagintedList <Country> > GetCountriesAsync(CountryResourceParameters parameters)
{
var query = context.Countries.AsQueryable();
if (!string.IsNullOrEmpty(parameters.EnglishName))
{
var englishName = parameters.EnglishName.Trim().ToLowerInvariant();
query = query.Where(a => a.EnglishName.ToLowerInvariant() == englishName);
}
if (!string.IsNullOrEmpty(parameters.ChineseName))
{
//var chineseName = parameters.ChineseName.Trim().ToLowerInvariant();
query = query.Where(a => a.ChineseName.Equals(parameters.ChineseName));
}
//query = query.ApplySort(parameters.OrderBy, new CountryMappingProperty());
query = query.ApplySort(parameters.OrderBy, propertyMappingContainer.Resolve <CountryResource, Country>());
var count = await query.CountAsync();
var list = await query
.Skip(parameters.PageIndex *parameters.PageSize)
.Take(parameters.PageSize)
.ToListAsync();
return(new PagintedList <Country>(parameters.PageSize, parameters.PageIndex, count, list));
}
public async Task <PaginatedList <Country> > GetCountriesAsync(CountryResourceParameters parameters)
{
var query = _myContext.Countries.AsQueryable();
if (!string.IsNullOrEmpty(parameters.EnglishName))
{
var englishNameClause = parameters.EnglishName.Trim().ToLowerInvariant();
query = query.Where(x => x.EnglishName.ToLowerInvariant() == englishNameClause);
}
if (!string.IsNullOrEmpty(parameters.ChineseName))
{
var chineseNameClause = parameters.ChineseName.Trim().ToLowerInvariant();
query = query.Where(x => x.ChineseName.ToLowerInvariant() == chineseNameClause);
}
query = query.ApplySort(parameters.OrderBy, _propertyMappingContainer.Resolve <CountryResource, Country>());
var count = await query.CountAsync();
var items = await query
.Skip(parameters.PageSize *parameters.PageIndex)
.Take(parameters.PageSize).ToListAsync();
return(new PaginatedList <Country>(parameters.PageIndex, parameters.PageSize, count, items));
}
private IEnumerable <LinkResource> CreateLinksForCountries(CountryResourceParameters countryResourceParameters,
bool hasPrevious, bool hasNext)
{
var links = new List <LinkResource>
{
new LinkResource(
CreateCountryUri(countryResourceParameters, PaginationResourceUriType.CurrentPage),
"self", "GET")
};
if (hasPrevious)
{
links.Add(
new LinkResource(
CreateCountryUri(countryResourceParameters, PaginationResourceUriType.PreviousPage),
"previous_page", "GET"));
}
if (hasNext)
{
links.Add(
new LinkResource(
CreateCountryUri(countryResourceParameters, PaginationResourceUriType.NextPage),
"next_page", "GET"));
}
return(links);
}
//首先我们需要从参数(query string参数)传进来pageIndex和pageSize，还要赋默认值，以防止API的消费者没有设置pageIndex和pageSize；由于pageSize的值是由API的消费者来定的，所以应该在后端设定一个最大值，以免API的消费者设定一个很大的值
//public async Task<IActionResult> Get([FromQuery] int pageIndex =0, int pageSize = 10)
public async Task <IActionResult> GetCountries(CountryResourceParameters countryResourceParameters)
{
var pagedList = await _countryRepository.GetCountriesAsync(countryResourceParameters);
var countryResources = _mapper.Map <List <CountryResource> >(pagedList);
var previousPageLink = pagedList.HasPrevious ?
CreateCountryUri(countryResourceParameters, PaginationResourceUriType.PreviousPage) : null;
var nextPageLink = pagedList.HasNext ?
CreateCountryUri(countryResourceParameters, PaginationResourceUriType.NextPage) : null;
var meta = new
{
pagedList.TotalItemsCount,
pagedList.PaginationBase.PageSize,
pagedList.PaginationBase.PageIndex,
pagedList.PageCount,
previousPageLink,
nextPageLink
};
Response.Headers.Add("X-Pagination", JsonConvert.SerializeObject(meta));
return(Ok(countryResources));
}
public async Task <IActionResult> Get(CountryResourceParameters parameters,
[FromHeader(Name = "Accept")] string mediaType)
{
var countries = await countryRepository.GetCountriesAsync(parameters);
var countryResource = mapper.Map <List <CountryResource> >(countries);
if (mediaType == "application/vnd.mycompany.heatoas+json")
{
var meta = new
{
countries.TotalItemsCount,
countries.PaginationBase.PageIndex,
countries.PaginationBase.PageSize,
countries.PageCount,
};
Response.Headers.Add("X-Pagination", JsonConvert.SerializeObject(meta));
var links = CreateCountriesLinks(parameters, countries.HasPrevious, countries.HasNext);
var shapedResource = countryResource.ToDynamicIEnumerable(parameters.Fields);
var shapedResourceWithLinks = shapedResource.Select(country =>
{
var countryDit = country as IDictionary <string, object>;
var countryLinks = CreateCountryLinks((Guid)countryDit["Id"], parameters.Fields);
countryDit.Add("links", countryLinks);
return(countryDit);
});
var linkedCountries = new
{
value = shapedResourceWithLinks,
links,
};
return(Ok(linkedCountries));
}
else
{
var perviousPagelink = countries.HasPrevious ?
CreateCountryUri(parameters, PaginationResourceUriType.PreviousPage):null;
var nextPagelink = countries.HasNext ?
CreateCountryUri(parameters, PaginationResourceUriType.NextPage) : null;
var meta = new
{
countries.TotalItemsCount,
countries.PaginationBase.PageIndex,
countries.PaginationBase.PageSize,
countries.PageCount,
perviousPagelink,
nextPagelink
};
Response.Headers.Add("X-Pagination", JsonConvert.SerializeObject(meta));
return(Ok(countryResource.ToDynamicIEnumerable(parameters.Fields)));
}
}
//需要确保的是要在迭代发生之前，使用Skip()和Take()以及Where()
public async Task <PaginatedList <Country> > GetCountriesAsync(CountryResourceParameters parameters)
{
// return await _myContext.Countries
// .OrderBy(x => x.Id)
// .Skip(parameters.PageSize * parameters.PageIndex)
// .Take(parameters.PageSize)
// .ToListAsync();
var query = _myContext.Countries.OrderBy(x => x.Id);
var count = await query.CountAsync();
var items = await query
.Skip(parameters.PageSize *parameters.PageIndex)
.Take(parameters.PageSize).ToListAsync();
return(new PaginatedList <Country>(parameters.PageIndex, parameters.PageSize, count, items));
}
private string CreateCountryUri(CountryResourceParameters parameters, PaginationResourceUriType uriType)
{
switch (uriType)
{
case PaginationResourceUriType.PreviousPage:
var previousParameters = new
{
pageIndex = parameters.PageIndex - 1,
pageSize = parameters.PageSize,
orderBy = parameters.OrderBy,
fields = parameters.Fields,
chineseName = parameters.ChineseName,
englishName = parameters.EnglishName
};
return(_urlHelper.Link("GetCountries", previousParameters));
case PaginationResourceUriType.NextPage:
var nextParameters = new
{
pageIndex = parameters.PageIndex + 1,
pageSize = parameters.PageSize,
orderBy = parameters.OrderBy,
fields = parameters.Fields,
chineseName = parameters.ChineseName,
englishName = parameters.EnglishName
};
return(_urlHelper.Link("GetCountries", nextParameters));
default:
case PaginationResourceUriType.CurrentPage:
var currentParameters = new
{
pageIndex = parameters.PageIndex,
pageSize = parameters.PageSize,
orderBy = parameters.OrderBy,
fields = parameters.Fields,
chineseName = parameters.ChineseName,
englishName = parameters.EnglishName
};
return(_urlHelper.Link("GetCountries", currentParameters));
}
}
private string CreateCountriesResourceUri(CountryResourceParameters countryResourceParameters, ResourceUriType type)
{
switch (type)
{
case ResourceUriType.PreviousPage:
return(_urlHelper.Link("GetCountries",
new
{
fields = countryResourceParameters.Fields,
orderBy = countryResourceParameters.OrderBy,
searchQuery = countryResourceParameters.SearchQuery,
name = countryResourceParameters.Name,
pageNumber = countryResourceParameters.PageNumber - 1,
pageSize = countryResourceParameters.PageSize
}));
case ResourceUriType.NextPage:
return(_urlHelper.Link("GetCountries",
new
{
fields = countryResourceParameters.Fields,
orderBy = countryResourceParameters.OrderBy,
searchQuery = countryResourceParameters.SearchQuery,
name = countryResourceParameters.Name,
pageNumber = countryResourceParameters.PageNumber + 1,
pageSize = countryResourceParameters.PageSize
}));
default:
return(_urlHelper.Link("GetCountries",
new
{
fields = countryResourceParameters.Fields,
orderBy = countryResourceParameters.OrderBy,
searchQuery = countryResourceParameters.SearchQuery,
name = countryResourceParameters.Name,
pageNumber = countryResourceParameters.PageNumber,
pageSize = countryResourceParameters.PageSize
}));
}
}
public IActionResult GetCountries(CountryResourceParameters countryResourceParameters)
{
if (!_propertyMappingService.ValidMappingExistsFor <CountryApiModel, Country>(countryResourceParameters.OrderBy))
{
return(BadRequest());
}
if (!_typeHelperService.TypeHasProperties <CountryApiModel>(countryResourceParameters.Fields))
{
return(BadRequest());
}
var countriesFromRepo = _countryRepository.GetCountries(countryResourceParameters);
var previousPageLink = countriesFromRepo.HasPrevious
? CreateCountriesResourceUri(countryResourceParameters, ResourceUriType.PreviousPage)
: null;
var nextPageLink = countriesFromRepo.HasNext
? CreateCountriesResourceUri(countryResourceParameters, ResourceUriType.NextPage)
: null;
var paginationMetadata = new
{
totalCount = countriesFromRepo.TotalCount,
pageSize = countriesFromRepo.PageSize,
currentPage = countriesFromRepo.CurrentPage,
totalPages = countriesFromRepo.TotalPages,
previousPageLink = previousPageLink,
nextPageLink = nextPageLink
};
Response.Headers.Add("X-Pagination", Newtonsoft.Json.JsonConvert.SerializeObject(paginationMetadata));
var countries = Mapper.Map <IEnumerable <CountryApiModel> >(countriesFromRepo);
return(Ok(countries.ShapeData(countryResourceParameters.Fields)));
}
public PagedList <Country> GetCountries(CountryResourceParameters countryResourceParameters)
{
//var collectionBeforePaging = _context.Countries
// .OrderBy(a => a.Name).AsQueryable();
var collectionBeforePaging =
_context.Countries.ApplySort(countryResourceParameters.OrderBy,
_propertyMappingService.GetPropertyMapping <CountryApiModel, Country>());
if (!string.IsNullOrEmpty(countryResourceParameters.Deleted.ToString()))
{
var genreForWhereClause = countryResourceParameters.Deleted;
collectionBeforePaging =
collectionBeforePaging.Where(a => (a.DeleteDate == null) != genreForWhereClause);
}
if (!string.IsNullOrEmpty(countryResourceParameters.Name))
{
var genreForWhereClause = countryResourceParameters.Name.Trim().ToLowerInvariant();
collectionBeforePaging =
collectionBeforePaging.Where(a => a.Name.ToLowerInvariant() == genreForWhereClause);
}
if (!string.IsNullOrEmpty(countryResourceParameters.SearchQuery))
{
var searchQueryForWhereClause = countryResourceParameters.SearchQuery.Trim().ToLowerInvariant();
collectionBeforePaging =
collectionBeforePaging.Where(a => a.Name.ToLowerInvariant().Contains(searchQueryForWhereClause));
}
return(PagedList <Country> .Create(collectionBeforePaging,
countryResourceParameters.PageNumber,
countryResourceParameters.PageSize));
}
public async Task <IActionResult> GetCountries(CountryResourceParameters countryResourceParameters,
[FromHeader(Name = "Accept")] string mediaType)
{
foreach (var claim in User.Claims)
{
Console.WriteLine(claim.Type + ", " + claim.Value);
}
if (!_propertyMappingContainer.ValidMappingExistsFor <CountryResource, Country>(countryResourceParameters.OrderBy))
{
return(BadRequest("Can't find the fields for sorting."));
}
if (!_typeHelperService.TypeHasProperties <CountryResource>(countryResourceParameters.Fields))
{
return(BadRequest("Can't find the fields on Resource."));
}
var pagedList = await _countryRepository.GetCountriesAsync(countryResourceParameters);
var countryResources = _mapper.Map <List <CountryResource> >(pagedList);
if (mediaType == "application/vnd.solenovex.hateoas+json")
{
var meta = new
{
pagedList.TotalItemsCount,
pagedList.PaginationBase.PageSize,
pagedList.PaginationBase.PageIndex,
pagedList.PageCount
};
Response.Headers.Add("X-Pagination", JsonConvert.SerializeObject(meta, new JsonSerializerSettings
{
ContractResolver = new CamelCasePropertyNamesContractResolver()
}));
var links = CreateLinksForCountries(countryResourceParameters, pagedList.HasPrevious, pagedList.HasNext);
var shapedResources = countryResources.ToDynamicIEnumerable(countryResourceParameters.Fields);
var shapedResourcesWithLinks = shapedResources.Select(country =>
{
var countryDict = country as IDictionary <string, object>;
var countryLinks = CreateLinksForCountry((int)countryDict["Id"], countryResourceParameters.Fields);
countryDict.Add("links", countryLinks);
return(countryDict);
});
var linkedCountries = new
{
value = shapedResourcesWithLinks,
links
};
return(Ok(linkedCountries));
}
else
{
var previousPageLink = pagedList.HasPrevious ?
CreateCountryUri(countryResourceParameters,
PaginationResourceUriType.PreviousPage) : null;
var nextPageLink = pagedList.HasNext ?
CreateCountryUri(countryResourceParameters,
PaginationResourceUriType.NextPage) : null;
var meta = new
{
pagedList.TotalItemsCount,
pagedList.PaginationBase.PageSize,
pagedList.PaginationBase.PageIndex,
pagedList.PageCount,
previousPageLink,
nextPageLink
};
Response.Headers.Add("X-Pagination", JsonConvert.SerializeObject(meta, new JsonSerializerSettings
{
ContractResolver = new CamelCasePropertyNamesContractResolver()
}));
return(Ok(countryResources.ToDynamicIEnumerable(countryResourceParameters.Fields)));
}
}
