Elasticsearch

Full-text search and analytics over Elasticsearch's REST API. Use it for search APIs, product catalogs, log analytics, or any scenario where you need powerful text matching, filtering, and aggregations beyond what SQL offers.

Multi-node clusters use round-robin load balancing automatically.

Configuration

connector "es" {
  type     = "elasticsearch"
  url      = "http://localhost:9200"
  username = env("ES_USER")
  password = env("ES_PASSWORD")
  timeout  = "30s"
}

Option	Type	Default	Description
url	string	"http://localhost:9200"	Elasticsearch node URL
username	string	—	Basic auth username
password	string	—	Basic auth password
timeout	duration	"30s"	Request timeout

The index is specified per-flow via the target attribute in flow to or step blocks.

Operations

Operation	Direction	Description
search	read	Full-text query DSL
get	read	Document by ID
count	read	Count matching documents
aggregate	read	Aggregation queries
index	write	Create or replace a document
update	write	Partial document update
delete	write	Delete by ID
bulk	write	Batch operations

Mycel's standard query model maps to Elasticsearch: filters become bool.must terms, pagination maps to size/from, ordering maps to sort, and field selection maps to _source includes.

Example

# Full-text search with query DSL
flow "search_products" {
  from {
    connector = "api"
    operation = "GET /search"
  }

  step "results" {
    connector = "es"
    operation = "search"
    target    = "products"
    body = {
      "query" = {
        "multi_match" = {
          "query"  = "input.query.q"
          "fields" = ["name^2", "description"]
        }
      }
    }
  }

  transform { output.results = "step.results" }
  to { response }
}

# Index a document
flow "index_product" {
  from {
    connector = "api"
    operation = "POST /products"
  }
  to {
    connector = "es"
    target    = "products"
    operation = "index"
  }
}

See the elasticsearch example for a complete working setup.

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Full configuration reference: See Elasticsearch in the Configuration Reference.