Hi,
I'm going to use Redis cache on my app.Other than the Redis cache,I would like to load my drop down related data (master data) within the application layer's method (MycompanyApplicationModule).Then users will not need to wait for the data base retrievals even for the first time.Hence I'm using Cache,it will not have 2nd time db call anyway. I think we can do it on the PreInitialize() method. So could you tell me how can I do that ? Is this the right approach ? Hope you'll give feedback.Thanks.
RedisConnectorHelper.cs
public class RedisConnectorHelper
{
private static readonly Lazy<ConnectionMultiplexer> LazyConnection =
new Lazy<ConnectionMultiplexer>(() => ConnectionMultiplexer.Connect("localhost"));
public static ConnectionMultiplexer Connection => LazyConnection.Value;
}
js
vm.getAllCities = function () {
cityService.getAllCitiesAsync().success(function (result) {
vm.cities = result.items;
vm.toRefreshCitySearchableDropDown();
if (vm.cityId != 0) {
vm.getCityName(vm.cityId);
}
});
};
vm.getAllCities();
Html
<div class="form-group">
<label class="control-label">@L("City")</label>
<select id="cityDropDown" required
class="form-control"
ng-options="a.id as a.name + ' | '+ a.zipCode for a in vm.cities"
ng-model="vm.property.address.cityId"
ui-jq="selectpicker"
ui-options='{ iconBase: "famfamfam-flag", tickIcon: "fa fa-check" }'
ng-change="vm.changedCity(vm.property.address.cityId)"
data-live-search="true" title="@L("PfSelectCity")">
<option value=""></option>
</select>
</div>
CityAppService
public async Task<ListResultOutput<CityListDto>> GetAllCitiesAsync()
{
var cache = RedisConnectorHelper.Connection.GetDatabase();
var values = JsonConvert.DeserializeObject<List<CityListDto>>(cache.StringGet(AppConsts.Cities));
if (values != null) return new ListResultOutput<CityListDto>(values.OrderBy(o => o.Name).ToList());//from cache
var cities = await _cityRepository.GetAllListAsync();
cache.StringSet(AppConsts.Cities, JsonConvert.SerializeObject(cities.OrderBy(o => o.Name).MapTo<List<CityListDto>>()));//to cache
return new ListResultOutput<CityListDto>(cities.OrderBy(o => o.Name).MapTo<List<CityListDto>>());
}
3 Answer(s)
-
0
Hi,
You can not cache data in PreInitialize. You can do in PostInitialize, since you can not run query before initialize. I did not see caching in the code you shared?
-
0
Hi, Yes,I have updated the cache details.Please see that. Yes,I need to do it on the
PostInitialize()method.Could you tell me how to do that ? The above mentioned cache details have been implemented on the Application layer.Thanks. -
0
Hi,
Caching is generally done as lazy-load:
- When you first time request it, it's got from database. For next requests, it's retrieved from cache.
- If the cache is not used for a long time, it's automatically cleared. So, next request will again get from database.
- If the data in cache changes somehow, you must drop the cache data because it's not valid.
I strongly suggest this pattern, because this is nature of caching. Otherwise, you will have problems. In addition to that, you can request data from cache in PostInitialize method of your module. Thus, it's loaded once the application starts (and first user request directly get from cache).
I will show you an example: I store tenant features on the cache and then not using db to check tenant features every time. How did I do it..
Created a class to store data in the cache: <a class="postlink" href="https://github.com/aspnetboilerplate/module-zero/blob/master/src/Abp.Zero/MultiTenancy/TenantFeatureCacheItem.cs">https://github.com/aspnetboilerplate/mo ... cheItem.cs</a> Cache data class should not include entities (Since they are not well serializable).
Getting data from cache or db: <a class="postlink" href="https://github.com/aspnetboilerplate/module-zero/blob/master/src/Abp.Zero/Application/Features/AbpFeatureValueStore.cs#L112">https://github.com/aspnetboilerplate/mo ... re.cs#L112</a>
I created a class to remove an item from cache when it's changed: <a class="postlink" href="https://github.com/aspnetboilerplate/module-zero/blob/master/src/Abp.Zero/MultiTenancy/TenantFeatureCacheItemInvalidator.cs">https://github.com/aspnetboilerplate/mo ... lidator.cs</a>
