Dowser.
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The OpenSearch cluster info API — the endpoints tagged Info in the
OpenSearch OpenAPI specification.
Built on Dowser.Client. Neither endpoint takes an OpenSearch attribute at
all, so both functions only carry the transport options.
All options are forwarded to Dowser.Client.request/4, e.g. :context,
:params (query-string parameters), :format, :keys and :http_opts
(including :headers) — plus :codec, this package's own, which picks the
per-field codec for this one request (see Dowser.Opensearch.Codec).
On a 2xx response info/1 returns {:ok, body} with the decoded response
body. A non-2xx response returns {:error, %Dowser.Opensearch.Error{}}; a
transport, encoding or decoding failure returns {:error, exception} from
Dowser.Client. The bang variant returns the body directly or raises the
error exception.
Summary
Functions
Gets the basic information about the cluster — GET /
(Cluster info API).
Like info/1, but returns the body directly or raises the error exception.
Checks whether the cluster is up — HEAD /
(Ping API).
Like ping/1, but returns the boolean directly (404 → false) or raises
the error exception.
Types
@type body() :: term()
@type exists_result() :: {:ok, boolean()} | {:error, Exception.t()}
@type result() :: {:ok, body()} | {:error, Exception.t()}
Functions
Gets the basic information about the cluster — GET /
(Cluster info API).
The response carries the node name, the cluster name and UUID, the distribution and version, and the tagline, which makes it the usual way to check that a cluster is reachable and to read its version:
{:ok, info} = Dowser.Opensearch.Info.info()
info["version"]["distribution"]
#=> "opensearch"
info["version"]["number"]
#=> "2.13.0"A cluster running in Elasticsearch compatibility mode reports the
Elasticsearch version it emulates under version.number, with the real one
in version.distribution/version.build_type — so read distribution
rather than number to tell the two apart.
Options
Only the transport options listed in the module documentation, e.g.
:context to pick the cluster to query.
Like info/1, but returns the body directly or raises the error exception.
@spec ping(keyword()) :: exists_result()
Checks whether the cluster is up — HEAD /
(Ping API).
The body-less counterpart of info/1: it answers the liveness question
without transferring or decoding the cluster metadata.
Dowser.Opensearch.Info.ping?()
#=> trueReturns {:ok, true} on a 2xx and {:ok, false} on a 404. Note that a
cluster that cannot be reached at all is a transport failure, not a false:
that comes back as {:error, exception}, since "answered no" and "did not
answer" are different things.
Options
Only the transport options listed in the module documentation.
Like ping/1, but returns the boolean directly (404 → false) or raises
the error exception.