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# Auto generated from commit f284cc16f4d4b4289bc679aa1529bb504190fe80
# @see https://github.com/elastic/elasticsearch-specification
#
module ElasticsearchServerless
  module API
    module Actions
      # Reindex documents.
      # Copy documents from a source to a destination.
      # You can copy all documents to the destination index or reindex a subset of the documents.
      # The source can be any existing index, alias, or data stream.
      # The destination must differ from the source.
      # For example, you cannot reindex a data stream into itself.
      # IMPORTANT: Reindex requires +_source+ to be enabled for all documents in the source.
      # The destination should be configured as wanted before calling the reindex API.
      # Reindex does not copy the settings from the source or its associated template.
      # Mappings, shard counts, and replicas, for example, must be configured ahead of time.
      # If the Elasticsearch security features are enabled, you must have the following security privileges:
      # * The +read+ index privilege for the source data stream, index, or alias.
      # * The +write+ index privilege for the destination data stream, index, or index alias.
      # * To automatically create a data stream or index with a reindex API request, you must have the +auto_configure+, +create_index+, or +manage+ index privilege for the destination data stream, index, or alias.
      # * If reindexing from a remote cluster, the +source.remote.user+ must have the +monitor+ cluster privilege and the +read+ index privilege for the source data stream, index, or alias.
      # If reindexing from a remote cluster, you must explicitly allow the remote host in the +reindex.remote.whitelist+ setting.
      # Automatic data stream creation requires a matching index template with data stream enabled.
      # The +dest+ element can be configured like the index API to control optimistic concurrency control.
      # Omitting +version_type+ or setting it to +internal+ causes Elasticsearch to blindly dump documents into the destination, overwriting any that happen to have the same ID.
      # Setting +version_type+ to +external+ causes Elasticsearch to preserve the +version+ from the source, create any documents that are missing, and update any documents that have an older version in the destination than they do in the source.
      # Setting +op_type+ to +create+ causes the reindex API to create only missing documents in the destination.
      # All existing documents will cause a version conflict.
      # IMPORTANT: Because data streams are append-only, any reindex request to a destination data stream must have an +op_type+ of +create+.
      # A reindex can only add new documents to a destination data stream.
      # It cannot update existing documents in a destination data stream.
      # By default, version conflicts abort the reindex process.
      # To continue reindexing if there are conflicts, set the +conflicts+ request body property to +proceed+.
      # In this case, the response includes a count of the version conflicts that were encountered.
      # Note that the handling of other error types is unaffected by the +conflicts+ property.
      # Additionally, if you opt to count version conflicts, the operation could attempt to reindex more documents from the source than +max_docs+ until it has successfully indexed +max_docs+ documents into the target or it has gone through every document in the source query.
      # NOTE: The reindex API makes no effort to handle ID collisions.
      # The last document written will "win" but the order isn't usually predictable so it is not a good idea to rely on this behavior.
      # Instead, make sure that IDs are unique by using a script.
      # **Running reindex asynchronously**
      # If the request contains +wait_for_completion=false+, Elasticsearch performs some preflight checks, launches the request, and returns a task you can use to cancel or get the status of the task.
      # Elasticsearch creates a record of this task as a document at +_tasks/<task_id>+.
      # **Reindex from multiple sources**
      # If you have many sources to reindex it is generally better to reindex them one at a time rather than using a glob pattern to pick up multiple sources.
      # That way you can resume the process if there are any errors by removing the partially completed source and starting over.
      # It also makes parallelizing the process fairly simple: split the list of sources to reindex and run each list in parallel.
      # For example, you can use a bash script like this:
      # +
      # for index in i1 i2 i3 i4 i5; do
      #   curl -HContent-Type:application/json -XPOST localhost:9200/_reindex?pretty -d'{
      #     "source": {
      #       "index": "'$index'"
      #     },
      #     "dest": {
      #       "index": "'$index'-reindexed"
      #     }
      #   }'
      # done
      # +
      # **Throttling**
      # Set +requests_per_second+ to any positive decimal number (+1.4+, +6+, +1000+, for example) to throttle the rate at which reindex issues batches of index operations.
      # Requests are throttled by padding each batch with a wait time.
      # To turn off throttling, set +requests_per_second+ to +-1+.
      # The throttling is done by waiting between batches so that the scroll that reindex uses internally can be given a timeout that takes into account the padding.
      # The padding time is the difference between the batch size divided by the +requests_per_second+ and the time spent writing.
      # By default the batch size is +1000+, so if +requests_per_second+ is set to +500+:
      # +
      # target_time = 1000 / 500 per second = 2 seconds
      # wait_time = target_time - write_time = 2 seconds - .5 seconds = 1.5 seconds
      # +
      # Since the batch is issued as a single bulk request, large batch sizes cause Elasticsearch to create many requests and then wait for a while before starting the next set.
      # This is "bursty" instead of "smooth".
      # **Slicing**
      # Reindex supports sliced scroll to parallelize the reindexing process.
      # This parallelization can improve efficiency and provide a convenient way to break the request down into smaller parts.
      # NOTE: Reindexing from remote clusters does not support manual or automatic slicing.
      # You can slice a reindex request manually by providing a slice ID and total number of slices to each request.
      # You can also let reindex automatically parallelize by using sliced scroll to slice on +_id+.
      # The +slices+ parameter specifies the number of slices to use.
      # Adding +slices+ to the reindex request just automates the manual process, creating sub-requests which means it has some quirks:
      # * You can see these requests in the tasks API. These sub-requests are "child" tasks of the task for the request with slices.
      # * Fetching the status of the task for the request with +slices+ only contains the status of completed slices.
      # * These sub-requests are individually addressable for things like cancellation and rethrottling.
      # * Rethrottling the request with +slices+ will rethrottle the unfinished sub-request proportionally.
      # * Canceling the request with +slices+ will cancel each sub-request.
      # * Due to the nature of +slices+, each sub-request won't get a perfectly even portion of the documents. All documents will be addressed, but some slices may be larger than others. Expect larger slices to have a more even distribution.
      # * Parameters like +requests_per_second+ and +max_docs+ on a request with +slices+ are distributed proportionally to each sub-request. Combine that with the previous point about distribution being uneven and you should conclude that using +max_docs+ with +slices+ might not result in exactly +max_docs+ documents being reindexed.
      # * Each sub-request gets a slightly different snapshot of the source, though these are all taken at approximately the same time.
      # If slicing automatically, setting +slices+ to +auto+ will choose a reasonable number for most indices.
      # If slicing manually or otherwise tuning automatic slicing, use the following guidelines.
      # Query performance is most efficient when the number of slices is equal to the number of shards in the index.
      # If that number is large (for example, +500+), choose a lower number as too many slices will hurt performance.
      # Setting slices higher than the number of shards generally does not improve efficiency and adds overhead.
      # Indexing performance scales linearly across available resources with the number of slices.
      # Whether query or indexing performance dominates the runtime depends on the documents being reindexed and cluster resources.
      # **Modify documents during reindexing**
      # Like +_update_by_query+, reindex operations support a script that modifies the document.
      # Unlike +_update_by_query+, the script is allowed to modify the document's metadata.
      # Just as in +_update_by_query+, you can set +ctx.op+ to change the operation that is run on the destination.
      # For example, set +ctx.op+ to +noop+ if your script decides that the document doesn’t have to be indexed in the destination. This "no operation" will be reported in the +noop+ counter in the response body.
      # Set +ctx.op+ to +delete+ if your script decides that the document must be deleted from the destination.
      # The deletion will be reported in the +deleted+ counter in the response body.
      # Setting +ctx.op+ to anything else will return an error, as will setting any other field in +ctx+.
      # Think of the possibilities! Just be careful; you are able to change:
      # * +_id+
      # * +_index+
      # * +_version+
      # * +_routing+
      # Setting +_version+ to +null+ or clearing it from the +ctx+ map is just like not sending the version in an indexing request.
      # It will cause the document to be overwritten in the destination regardless of the version on the target or the version type you use in the reindex API.
      # **Reindex from remote**
      # Reindex supports reindexing from a remote Elasticsearch cluster.
      # The +host+ parameter must contain a scheme, host, port, and optional path.
      # The +username+ and +password+ parameters are optional and when they are present the reindex operation will connect to the remote Elasticsearch node using basic authentication.
      # Be sure to use HTTPS when using basic authentication or the password will be sent in plain text.
      # There are a range of settings available to configure the behavior of the HTTPS connection.
      # When using Elastic Cloud, it is also possible to authenticate against the remote cluster through the use of a valid API key.
      # Remote hosts must be explicitly allowed with the +reindex.remote.whitelist+ setting.
      # It can be set to a comma delimited list of allowed remote host and port combinations.
      # Scheme is ignored; only the host and port are used.
      # For example:
      # +
      # reindex.remote.whitelist: [otherhost:9200, another:9200, 127.0.10.*:9200, localhost:*"]
      # +
      # The list of allowed hosts must be configured on any nodes that will coordinate the reindex.
      # This feature should work with remote clusters of any version of Elasticsearch.
      # This should enable you to upgrade from any version of Elasticsearch to the current version by reindexing from a cluster of the old version.
      # WARNING: Elasticsearch does not support forward compatibility across major versions.
      # For example, you cannot reindex from a 7.x cluster into a 6.x cluster.
      # To enable queries sent to older versions of Elasticsearch, the +query+ parameter is sent directly to the remote host without validation or modification.
      # NOTE: Reindexing from remote clusters does not support manual or automatic slicing.
      # Reindexing from a remote server uses an on-heap buffer that defaults to a maximum size of 100mb.
      # If the remote index includes very large documents you'll need to use a smaller batch size.
      # It is also possible to set the socket read timeout on the remote connection with the +socket_timeout+ field and the connection timeout with the +connect_timeout+ field.
      # Both default to 30 seconds.
      # **Configuring SSL parameters**
      # Reindex from remote supports configurable SSL settings.
      # These must be specified in the +elasticsearch.yml+ file, with the exception of the secure settings, which you add in the Elasticsearch keystore.
      # It is not possible to configure SSL in the body of the reindex request.
      #
      # @option arguments [Boolean] :refresh If +true+, the request refreshes affected shards to make this operation visible to search.
      # @option arguments [Float] :requests_per_second The throttle for this request in sub-requests per second.
      #  By default, there is no throttle. Server default: -1.
      # @option arguments [Time] :scroll The period of time that a consistent view of the index should be maintained for scrolled search.
      # @option arguments [Integer, String] :slices The number of slices this task should be divided into.
      #  It defaults to one slice, which means the task isn't sliced into subtasks.Reindex supports sliced scroll to parallelize the reindexing process.
      #  This parallelization can improve efficiency and provide a convenient way to break the request down into smaller parts.NOTE: Reindexing from remote clusters does not support manual or automatic slicing.If set to +auto+, Elasticsearch chooses the number of slices to use.
      #  This setting will use one slice per shard, up to a certain limit.
      #  If there are multiple sources, it will choose the number of slices based on the index or backing index with the smallest number of shards. Server default: 1.
      # @option arguments [Time] :timeout The period each indexing waits for automatic index creation, dynamic mapping updates, and waiting for active shards.
      #  By default, Elasticsearch waits for at least one minute before failing.
      #  The actual wait time could be longer, particularly when multiple waits occur. Server default: 1m.
      # @option arguments [Integer, String] :wait_for_active_shards The number of shard copies that must be active before proceeding with the operation.
      #  Set it to +all+ or any positive integer up to the total number of shards in the index (+number_of_replicas+1+).
      #  The default value is one, which means it waits for each primary shard to be active. Server default: 1.
      # @option arguments [Boolean] :wait_for_completion If +true+, the request blocks until the operation is complete. Server default: true.
      # @option arguments [Boolean] :require_alias If +true+, the destination must be an index alias.
      # @option arguments [Hash] :headers Custom HTTP headers
      # @option arguments [Hash] :body request body
      #
      # @see https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-reindex
      #
      def reindex(arguments = {})
        request_opts = { endpoint: arguments[:endpoint] || 'reindex' }

        raise ArgumentError, "Required argument 'body' missing" unless arguments[:body]

        arguments = arguments.clone
        headers = arguments.delete(:headers) || {}

        body = arguments.delete(:body)

        method = ElasticsearchServerless::API::HTTP_POST
        path   = '_reindex'
        params = Utils.process_params(arguments)

        ElasticsearchServerless::API::Response.new(
          perform_request(method, path, params, body, headers, request_opts)
        )
      end
    end
  end
end