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" }}}'
