Okanjo Elasticsearch Service

Service for interfacing with Elasticsearch for the Okanjo App ecosystem.

This package wraps interfacing with Elasticsearch, so:

• Common elastic operations are simplified
• Built in error reporting for common operations

Installing

Add to your project like so:

npm install okanjo-app-elastic

Peer dependency: Requires @elastic/elasticsearch module. Version >= 6.

Requires the okanjo-app module.

Example Usage

An example application can be found in docs/example-app. It demonstrates creating an index, loading documents, and searching.

ElasticService

Elasticsearch management class. Must be instantiated to be used.

Properties

• elastic.app – (read-only) The OkanjoApp instance provided when constructed
• elastic.config – (read-only) The configuration provided when constructed
• elastic.index – (read-only) The string name of the index this instance is bound to
• elastic.schema – (read-only) The index settings object for the index this instance is bound to
• elastic.types – (read-only) The enumeration of types of documents stored in the index
• elastic.client – (read-only) The elasticsearch client, usable for non-wrapped operations

Methods

new ElasticSearch(app, clientConfig, indexConfig)

Creates a new elastic service instance.

• app – The OkanjoApp instance to bind to
• clientConfig – The elasticsearch client configuration object
• indexConfig – The index configuration object.
  • indexConfig.name – String name of the index
  • indexConfig.schema – Index configuration. Should be an object that contains the mappings and settings of the index. This value is used as the body of the create index command.
  • indexConfig.types – (Legacy) Object map of key-value pairs, defining the types stored in the index.

elastic.exists([options])

Checks whether the index exists or not.

• options.index – Specifiy which index to check existence of
• options.* – Passed to the client.indices.exists request.
  Returns Promise<boolean>, where the result is true if the index exists or false if not.

elastic.ping()

Pings the elasticsearch server to see if it is available.
Returns Promise<boolean>, where the result is true if the available or false if not.

elastic.create([options])

Creates the elasticsearch index as configured by the name and schema.

• options.index – The name of the index to create, defaults to the service index property.
• options.schema – The index mappings and settings object or null to not set a body at all (e.g. use existing template), or leave unset to default to the service schema property.
• options.* – Additional create index request options Returns Promise<boolean>, where the result is true if the index was created.

elastic.delete([options])

Deletes the elasticsearch index as configured.

• options.index – The name of the index to create, defaults to the service index property.\
• options.* – Additional delete index request options Returns Promise<boolean>, where the result is true if the index was deleted or does not exist.

elastic.search(body, [options])

Searches the index for documents.

• body – Search request object, e.g. { query: { match_all: {} } }
• options.index – The name of the index to search, defaults to the service index property.
• options.* – Elastic request options, e.g. { limit: 5 }

elastic.get(id, [options])

Retrieves a doc from the index.

• id – The id of the document to fetch
• options.index – The name of the index the doc lives in, defaults to the service index property.
• options.* – Additional get request options

elastic.scroll(scrollId, [options])

Scrolls through an open search cursor. Renews the scroll cursor timeout to 5 minutes.

• scrollId – The active scroll id
• options.scroll – Time to let the cursor live. Defaults to 5m;
• options.* – Additional scroll request options

elastic.clearScroll(scrollId, [options])

Cleans up an open scroll cursor. Use this when done scrolling.

• scrollId – The active scroll id
• options.* – Additional clearScroll request options

elastic.bulk(body, [options,] callback)

Sends a batch of bulk operations to the index.

• body – The bulk body payload, array of operations
• options.index – The name of the index to operate on, defaults to the service index property.
• options.timeout – How long to let the bulk operation run. Defaults to 5m.
• options.refresh – true, false, wait_for - If true then refresh the effected shards to make this operation visible to search, if wait_for then wait for a refresh to make this operation visible to search, if false then do nothing with refreshes. Defaults to wait_for.
• options.* – Additional bulk request options

elastic.getMappings([options])

Gets the index's current mappings.

• options.index – The name of the index to operate on, defaults to the service index property.
• options.* – Additional getMappings request options

elastic.getSettings([options])

Gets the index's current settings.

• options.index – The name of the index to operate on, defaults to the service index property.
• options.* – Additional getMappings request options

elastic.putTemplate(name, index_patterns, schema, [options])

Creates or updates an index template.

• name – Template name
• index_patterns – Array of index pattern strings
• schema – Template body, e.g. { mappings: {}, settings: {} }
• options.* – Additional putTemplate request options

elastic.deleteTemplate(name, callback)

• name – Template name to delete
• options.* – Additional deleteTemplate request options

elastic.ensureTemplatedIndex(indexConfig, doCreate, [createSchema])

• indexConfig – Typical index configuration object

  • indexConfig.template_name – Name of the template
  • indexConfig.index_patterns - Array of the index patterns the template applies to
  • indexConfig.template – The index mappings and settings template
  • indexConfig.index.name – The name of the index to create

• doCreate - When truthy, the index will be created if not already present

• createSchema – Optional. Override the template mappings and settings, if desired. Defaults to null to inherit the template mappings and settings. Use this for overriding stuff like shard counts, e.g. { settings: { number_of_shards: 10 } }

Not Implemented?

Is your elastic client function missing? No problem.

Use elastic.client to talk to elasticsearch directly. Errors will not be automatically reported, so you'll need to do that yourself.

Events

This class fires no events.

Extending and Contributing

Our goal is quality-driven development. Please ensure that 100% of the code is covered with testing.

Before contributing pull requests, please ensure that changes are covered with unit tests, and that all are passing.

Testing

Before you can run the tests, you'll need a working elasticsearch server. We suggest using docker.

For example:

docker pull docker.elastic.co/elasticsearch/elasticsearch:6.8.22
sudo sysctl -w vm.max_map_count=262144
# docker-machine ssh default "sudo sysctl -w vm.max_map_count=262144"
docker run -d -p 9200:9200 -p 9300:9300 -e "discovery.type=single-node" docker.elastic.co/elasticsearch/elasticsearch:6.8.22

If you use docker via virtualbox (e.g. mac, windows), then you'll want that docker-machine line above instead.

To run unit tests and code coverage:

npm run report

Or with custom elasticseraach server

ES_HOST=elastic:[email protected]:9200 npm run report

Update the ES_HOST environment var to match your docker host (e.g. 127.0.0.1, user, pass, etc)

This will perform:

• Unit tests
• Code coverage report
• Code linting

Sometimes, that's overkill to quickly test a quick change. To run just the unit tests:

npm test

or if you have mocha installed globally, you may run mocha test instead.