In this repository you can find demo programs for working with Elasticsearch server.
First you need to raise the dockers server, this can be done using a makefile.
For cluster with 3 nodes we will uses docker-compose, it's already written in Makefile, so you can use it.
sudo make
To shutdown it also use make
sudo make clear
If you have some problems doc may help you!
For single node cluster we create network and up docker by hand. So you can use next expation:
sudo make docker-single-node
To shutdown it also use make
sudo make clear-single-node
Before filling db with data, you must set template to show Elasticsearch cluster how to represent index data. So you next command to set it.
go run template-setter.go
After this you may try to fulfill your db or reindex so index in it.
Next, you need to fill the server with data. In this case, the server has a single data stream with the index "test". You can use this commend to do it.
go run filler.go
Now filler.go use explicit mapping, where you can write more information about data. If types of data change, you must rewrite body of creation request. If index is already exist, request will return error, but filler will continue work.
Also creation request give ability to set number of replicas and shades for every index. Now you can experiment with fail-tolerens of you cluster.
The first example shows the easiest way to use search. You can match the lines with values that you need. This requests calculate _score for every matched line, so the result is sorted begins with the most similar result.
Use comment to look at the result
go run simple-search.go
Next example shows abilities of filter. You can use temp to match lines. In this case _score isn't calculated so the result isn't sorted. Next you can use range to find lines this fields in some range. Special words here are: lt (<), gt (>), e (=). e being written after lt and gt to create lte (<=) and gte (>=).
Use comment to look at the result
go run filter-demo.go
Always understand for what type you are filtering, if you are not sure, you can use keyword format
Last example shows how we can sort results. After filter call result isn't sort, so we can fix this problem. sort define the order of sorts rolls. Result will be sorted by first condition. If the is equal values, requests will use next condition and so on. You can use keywords asc or desc to set ascending order or descending order.
Use comment to look at the result
go run sort-demo.go
sort throws an error if it has nothing to sort, that is, if nothing was found as a result of the search or filtering
If you want to experiment with data in index="test" you may reuse filler.go to update data or add something new. But that may work not for all changes, so use delete.go to remove all data and setting for this data structure
go run deleter.go
Resetter might be use to change static setting on index. Firstly, you need to set template with correct setting. After you can run:
go run resseter.go
Implementation of this programme in not perfect.