Aggregator Provider Pattern is an extension of Provider Pattern, which enables us to create and utilize multiple instance of the class having the same provider interface.
In this pattern, there is an Aggregator class which implements the provider interface and contains a collection of instances of classes having the same provider interface.
The underlying caller class of this aggregator is simply unaware of how many provider instances do the caller Provider Aggregator contains, but all of the provider instances
will be utilized with a single invocation from the caller class.
Comparison with Provider Pattern
Provider Aggregator Pattern is fully compatible with the existing Provider Pattern and the power of provider pattern can be easily extended to use multiple providers
concurrently without any modification on the caller classes that were using a provider.
In short Provider Pattern is concerned with the utilization
of one of the available providers; whereas Aggregator Provider Pattern is concerned with the utilization of all of the available providers at the same time.
Aggregator Provider Pattern is useful when we need a configurable framework to add/remove multiple services used
by one caller/user. For instance we can have Logger Provider framework, where we need log info to be saved at text files, save to database and sent to email
addresses and so on. Having an easy configurable framework along with Aggregator Provider Pattern will enable us to add or remove more services without requiring
the code modification in the code that uses this provider.
Regarding the example case that just been described can utilize the Aggregator Provider Pattern, by creating the classes as illustrated above.
The code snippet below shows a basic usage of this pattern, where the last line will perform the log operation based in list of log providers loaded in the aggregator class dynamically.
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Mohammad Ashraful Alam is a Software Engineer, who is dedicated to Microsoft .NET based development. This Bangladeshi national is involved with project management and development of several US based software projects from his country. Already he has managed and developed 15 software projects, which are being used by several users of different countries, such as USA, Canada, Australia, and Bangladesh. While developing and managing a team, he contains and maintains a set of well defined engineering practices developed by him and other online developer community. Beside software development, he has also written several technical articles and research papers published by IEEE Computer Society and many other worlds recognized publishers.
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Due to his willingness to give effort to improve and share better software development practices, Ashraf has awarded as “Most Valuable Professional” (MVP) in ASP.NET category by Microsoft for multiple times, since 2007.
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