Skip to content

steemit/hive2elastic

Repository files navigation

hive2elastic

hive2elastic synchronises hive's hive_posts_cache table to a elasticsearch index and keeps it updated.

Before start

Some additional database objects have to be created on hive's database.

Follow steps below:

1- Stop hive. Make sure all hive processes stopped.

2- Create database objects on hive's database.

CREATE TABLE __h2e_posts
(
    post_id INTEGER PRIMARY KEY
);
CREATE TABLE __h2e_accounts
(
    account_id INTEGER PRIMARY KEY
);
INSERT INTO __h2e_posts (post_id) SELECT post_id FROM hive_posts_cache;
INSERT INTO __h2e_accounts (account_id) SELECT id FROM hive_accounts;
CREATE OR REPLACE FUNCTION __fn_h2e_posts()
  RETURNS TRIGGER AS
$func$
BEGIN   
    IF NOT EXISTS (SELECT post_id FROM __h2e_posts WHERE post_id = NEW.post_id) THEN
    	INSERT INTO __h2e_posts (post_id) VALUES (NEW.post_id);
	END IF;
	RETURN NEW;
END
$func$ LANGUAGE plpgsql;

CREATE OR REPLACE FUNCTION __fn_h2e_accounts()
  RETURNS TRIGGER AS
$func$
BEGIN   
    IF NOT EXISTS (SELECT account_id FROM __h2e_accounts WHERE account_id = NEW.id) THEN
    	INSERT INTO __h2e_accounts (account_id) VALUES (NEW.id);
	END IF;
	RETURN NEW;
END
$func$ LANGUAGE plpgsql;
CREATE TRIGGER __trg_h2e_posts
AFTER INSERT OR UPDATE ON hive_posts_cache
FOR EACH ROW EXECUTE PROCEDURE __fn_h2e_posts();

CREATE TRIGGER __trg_h2e_accounts
AFTER INSERT OR UPDATE ON hive_accounts
FOR EACH ROW EXECUTE PROCEDURE __fn_h2e_accounts();

3- Start hive

Make sure database credentials that you use has delete permission on __h2e_posts and __h2e_accounts table

Elasticsearch

You can find detailed installation instructions here

Installation

$ git clone https://github.com/esteemapp/hive2elastic
$ cd hive2elastic
$ pip3 install -e .

Configuration

You can configure hive2elastic by these arguments/environment variables:

Argument Environment Variable Description Default
--db-url DB_URL Connection string for hive database --
--es-url ES_URL Elasticsearch server address --
--es-index ES_INDEX Index name on elasticsearch hive_posts
--es-type ES_TYPE Type name on elasticsearch index posts
--es-index-reply ES_INDEX_REPLY Reply index name on elasticsearch hive_replies
--es-type-reply ES_TYPE_REPLY Reply type name on elasticsearch index replies
--bulk-size BULK_SIZE Number of documents to index in a single loop 500
--max-workers MAX_WORKERS Max workers for document preparation process 2

Example configuration and running

$ export DB_URL=postgresql://username:passwd@localhost:5432/hive 
$ export ES_URL=http://localhost:9200/
$ export BULK_SIZE=2000                 
$ export MAX_WORKERS=4

$ hive2elastic_post
$ hive2elastic_account