Reindexing documents with the Reindex API¶

Add new index with new mapping¶

PUT /reviews_new
{
  "mappings" : {
    "properties" : {
      "author" : {
        "properties" : {
          "email" : {
            "type" : "keyword",
            "ignore_above" : 256
          },
          "first_name" : {
            "type" : "text"
          },
          "last_name" : {
            "type" : "text"
          }
        }
      },
      "content" : {
        "type" : "text"
      },
      "created_at" : {
        "type" : "date"
      },
      "product_id" : {
        "type" : "keyword"
      },
      "rating" : {
        "type" : "float"
      }
    }
  }
}

Retrieve mapping¶

GET /reviews/_mappings

Reindex documents into reviews_new¶

POST /_reindex
{
  "source": {
    "index": "reviews"
  },
  "dest": {
    "index": "reviews_new"
  }
}

Delete all documents¶

POST /reviews_new/_delete_by_query
{
  "query": {
    "match_all": {}
  }
}

Convert product_id values to strings¶

POST /_reindex
{
  "source": {
    "index": "reviews"
  },
  "dest": {
    "index": "reviews_new"
  },
  "script": {
    "source": """
      if (ctx._source.product_id != null) {
        ctx._source.product_id = ctx._source.product_id.toString();
      }
    """
  }
}

Retrieve documents¶

GET /reviews_new/_search
{
  "query": {
    "match_all": {}
  }
}

Reindex specific documents¶

POST /_reindex
{
  "source": {
    "index": "reviews",
    "query": {
      "match_all": { }
    }
  },
  "dest": {
    "index": "reviews_new"
  }
}

Reindex only positive reviews¶

POST /_reindex
{
  "source": {
    "index": "reviews",
    "query": {
      "range": {
        "rating": {
          "gte": 4.0
        }
      }
    }
  },
  "dest": {
    "index": "reviews_new"
  }
}

Removing fields (source filtering)¶

POST /_reindex
{
  "source": {
    "index": "reviews",
    "_source": ["content", "created_at", "rating"]
  },
  "dest": {
    "index": "reviews_new"
  }
}

Changing a field's name¶

POST /_reindex
{
  "source": {
    "index": "reviews"
  },
  "dest": {
    "index": "reviews_new"
  },
  "script": {
    "source": """
      # Rename "content" field to "comment"
      ctx._source.comment = ctx._source.remove("content");
    """
  }
}

Ignore reviews with ratings below 4.0¶

POST /_reindex
{
  "source": {
    "index": "reviews"
  },
  "dest": {
    "index": "reviews_new"
  },
  "script": {
    "source": """
      if (ctx._source.rating < 4.0) {
        ctx.op = "noop"; # Can also be set to "delete"
      }
    """
  }
}