Setup and run ElasticSearch on Ubuntu 14.04 LTS

Run the following command to download the ElasticSearch 1.4.0:

> wget https://download.elasticsearch.org/elasticsearch/elasticsearch/elasticsearch-1.4.0.deb

Setup ElasticSearch

After download, run the following command to install the debian package:

> sudo dpkg -i elasticsearch-1.4.0.deb

After installation, the configuration files for ElasticSearch are stored in the following directory:

/etc/elasticsearch/

The bin folder for ElasticSearch can be found in the following directory:

/usr/share/elasticsearch/

Now navigate to the user root folder, and open the .bashrc for editing:

> sudo gedit $HOME/.bashrc

In the .bashrc file, add in the following lines to the end

export ES_HOME=/usr/share/elasticsearch
export ES_CONF_HOME=/etc/elasticsearch

Save and close the .bashrc file.

Check whether the elasticsearch is running as a service on Ubuntu:

> sudo service elasticsearch status

if not, start the elasticsearch service by running the following commands:

> sudo service elasticsearch start

Run the following command to test the ElasticSearch:

> curl localhost:9200

You can also open a web browser and enter "localhost:9200" to see ElasticSearch in action.

Create a document

From the terminal, execute a PUT call such as the following:

> curl -XPUT http://127.0.0.1:9200/myindex/mytype/1 -d '{
"start_time" : "2014-11-26T14:00:00",
"end_time" : "2014-11-26T17:30:00",
"subject" : "Elastic Search Tryout",
"agenda" : {
 "item 1" : "Create an index",
 "item 2" : "Delete an index",
 "item 3" : "Open an index",
 "item 4" : "Close an index" }
}'

The _index is specified as "myindex", _type is specified as "mytype", and _id is specified as "1". After the index has been created, it can be accessed by running a GET call

> curl http://127.0.0.1/myindex/mytype/1

We can execute another PUT call as below to generate one more document under myindex/mytype:

> curl -XPUT http://127.0.0.1:9200/myindex/mytype/2 -d '{
"start_time" : "2014-11-27T14:00:00",
"end_time" : "2014-11-27T17:30:00",
"subject" : "Elastic Search Tryout 2",
"agenda" : {
 "item 1" : "Create a document",
 "item 2" : "Delete a document",
 "item 3" : "Execute a search",
 "item 4" : "Delete by search" }
}'

After the index has been created, it can be accessed by running a GET call

> curl http://127.0.0.1/myindex/mytype/2

To create an index document with an auto-generated id, we can do the following:

We can execute another PUT call as below to generate one more document under myindex/mytype:

> curl -XPUT http://127.0.0.1:9200/myindex/mytype/11122 -d '{
"start_time" : "2014-11-28T14:00:00",
"end_time" : "2014-11-28T17:30:00",
"subject" : "Elastic Search Tryout 2",
"agenda" : {
 "item 1" : "Create a document with auto-generated  index",
 "item 2" : "Delete a document",
 "item 3" : "Execute a search",
 "item 4" : "Delete by search" }
}'

The _id should not be omitted, but can be generated using UUID from a programming language.

Create an index

Creating an index is the same as creating a document under an index. From the terminal, execute a PUT call such as the following:

> curl -XPUT http://127.0.0.1:9200/myindex/ -d '{
"settings"  {
 "item 1" : "true",
 "item 2" : "false",
 "item 3" : "1",
 "item 4" : "2" }
}'

Update a document by id

The following commands can be used to update the document with id=11122:

> curl -XPUT http://127.0.0.1:9200/myindex/mytype/11122 -d '{
"start_time" : "2014-11-21T14:00:00",
"end_time" : "2014-11-21T17:30:00",
"subject" : "Elastic Search Tryout 4",
"agenda" : {
 "item 1" : "Create a document with auto-generated  index",
 "item 2" : "Delete a document",
 "item 3" : "Execute a search",
 "item 4" : "Delete by search" }
}'

> curl -XPOST http://127.0.0.1:9200/myindex/mytype/11122 -d '{
"start_time" : "2014-11-24T14:00:00",
"end_time" : "2014-11-24T17:30:00",
"subject" : "Elastic Search Tryout 4",
"agenda" : {
 "item 1" : "Create a document with auto-generated  index",
 "item 2" : "Delete a document",
 "item 3" : "Execute a search",
 "item 4" : "Delete by search" }
}'

Delete a document

Deleting an document will remove the document from the ElasticSearch nodes. From the terminal, execute a DELETE call such as the following:

> curl -XDELETE http://127.0.0.1:9200/myindex/mytype/1

Delete an index

Deleting an index will remove the index from the ElasticSearch nodes. From the terminal, execute a DELETE call such as the following:

> curl -XDELETE http://127.0.0.1:9200/myindex/

Close an index

Closing an index is an alternative to the deleting the index as ElasticSearch put it in an offline mode. From the terminal, execute a POST call such as the following:

> curl -XPOST http://127.0.0.1:9200/myindex/_close

After this, if you run the "curl http://127.0.0.1:9200/myindex", you will get a "not found" message

Open an index

Opening an index will put the offline index online again. From the terminal, execute a POST call such as the following:

> curl -XPOST http://127.0.0.1:9200/myindex/_open

Execute an search

Suppose we want to retrieve a list of documents under an index having a particular word (e.g. "elastic") in their content, we can run a GET call from the terminal:

> curl -XGET http://127.0.0.1:9200/myindex/_search?q=elastic

Suppose we want to search in under a _type = "mytype":

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_search?q=elastic

The query can be written in more details by specifying search in the "subject" field of the document:

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_search -d '
{"query":{"match": { "subject" : "elastic" }}}'

To search all documents under myindex/mytype:

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_search -d '
{"query":{"match_all":{}}}'

Sort a search

Suppose we want the json results returned in certain sorting order (e.g. sort by start_time asc):

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_search -d '
{"query":{"match_all":{}}, "sort":[{"start_time": "asc" }]}'

Filtering

Suppose we want to search records filtered by a range of a values in one its parameter (said, age), and have a particular match query (said, "name" must be "James"), and we want the results to be returned sorted by a field (said, age). Furthermore, we also want the total number of records returned to be limited to 20:

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_search -d'
{
"from": 0, "size": 20,
"query" : {
  "filtered" :
    "query" : {
      "match" : { "name" : "James" }
     },
     "filter": {
       "range" : {
          "age" : { "lte" : 20, "gte" : 10 }
        }
     }
"sort" : { "age" : {"order" : "asc" }}
};

Count by Query

To count the number of documents in myindex/mytype matching a particular query, from the terminal, run the following command:

> curl -XGET http://127.0.0.1:9200/myindex/mytype/_count -d '
{"query":{"match": { "subject" : "elastic" }}}'

Delete by Query

To delete all documents in myindex/mytype matching a particular query,  from the terminal, run the following command:

> curl -XDELETE http://127.0.0.1:9200/myindex/mytype/_query -d '
{"query":{"match": { "subject" : "elastic" }}}'