How to Build A Search Page With ElasticSearch and .Net

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How to Build A Search Page With ElasticSearch and
.Net
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• ElasticSearch is credited to achieve fast search
  responses because it searches an index instead of
  searching the context directly.
• Very much like retrieving pages in a book related
  to a word by scanning the index at the back of a
  book, as instead of searching every word in every
  page of the book.
• This type of index is known as the inverted index
  because it inverts a page-centric data structure
  (page-gtwords) to a keyword-centric data structure
  (word-gtpages).
• This uses Apache Lucene to create and manage this
  inverted index.

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NEST

• To interact with Elasticsearch, NEST 2.3.0 is
  used which is one of two official .NET clients
  for Elasticsearch. NEST is a high-level client
  which tracks closely to Elasticsearch API. All
  the request and response objects are mapped. NEST
  provides the alternatives of either a syntax for
  creating queries, which resembles the structure
  of raw JSON requests to API, or the use of object
  initializer syntax.
• In order to build a web page, use Single Page
  Application (SPA) approach with AngularJS as MVVM
  framework. The client side will send AJAX
  requests to ASP.NET Web API 2. The Web API 2
  controller will use NEST to communicate with
  Elasticsearch.

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Installation of Elasticsearch

• Visit the web page, download an installer, unzip
  it and install in the mentioned three simple
  steps. It exposes an HTTP API so it is easy to
  use cURL to make requests but its recommended to
  use Sense which is Chrome extension. The
  Elasticsearch reference contains samples in a
  format called cURL.
• Although Elasticsearch is able to resolve the
  document type and its fields at index time, field
  mappings can be override or use attributes on
  fields in order to give for more advanced usages.
• In this example, the POCO class is decorated with
  some attributes so we need to create mappings
  with AutoMap.

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• After defining our mappings and created an index,
  we can seed it with documents. Elasticsearch does
  not give any handler to import specific file
  formats such as XML or CSV, but because it has
  client libraries for different languages, it is
  easy to build your own importer. As StackOverflow
  dump is in XML format, use .NET XmlReader class
  to read question rows, map them to an instance of
  Post and add objects to the collection.
• With this we conclude for today, stay connected
  with us for further discussion on this in our
  next article.
• If you want to learn ASP.Net and perfect yourself
  in .NET training, then CRB Tech Solutions would
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• Stay tuned to CRB Tech reviews for more technical
  optimization and other resources.

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Thank You.....!