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/// @startDocuBlock JSF_post_api_export
/// @brief export all documents from a collection, using a cursor
///
/// @RESTHEADER{POST /_api/export, Create export cursor}
///
/// @RESTBODYPARAM{flush,boolean,required,}
/// if set to *true*, a WAL flush operation will be executed prior to the
/// export. The flush operation will start copying documents from the WAL to the
/// collection's datafiles. There will be an additional wait time of up
/// to *flushWait* seconds after the flush to allow the WAL collector to change
/// the adjusted document meta-data to point into the datafiles, too.
/// The default value is *false* (i.e. no flush) so most recently inserted or
/// updated
/// documents from the collection might be missing in the export.
///
/// @RESTBODYPARAM{flushWait,integer,required,int64}
/// maximum wait time in seconds after a flush operation. The default
/// value is 10. This option only has an effect when *flush* is set to *true*.
///
/// @RESTBODYPARAM{count,boolean,required,}
/// boolean flag that indicates whether the number of documents
/// in the result set should be returned in the "count" attribute of the result
/// (optional).
/// Calculating the "count" attribute might in the future have a performance
/// impact so this option is turned off by default, and "count" is only returned
/// when requested.
///
/// @RESTBODYPARAM{batchSize,integer,required,int64}
/// maximum number of result documents to be transferred from
/// the server to the client in one roundtrip (optional). If this attribute is
/// not set, a server-controlled default value will be used.
///
/// @RESTBODYPARAM{limit,integer,required,int64}
/// an optional limit value, determining the maximum number of documents to
/// be included in the cursor. Omitting the *limit* attribute or setting it to 0 will
/// lead to no limit being used. If a limit is used, it is undefined which documents
/// from the collection will be included in the export and which will be excluded. 
/// This is because there is no natural order of documents in a collection.
///
/// @RESTBODYPARAM{ttl,integer,required,int64}
/// an optional time-to-live for the cursor (in seconds). The cursor will be
/// removed on the server automatically after the specified amount of time. This
/// is useful to ensure garbage collection of cursors that are not fully fetched
/// by clients. If not set, a server-defined value will be used.
///
/// @RESTBODYPARAM{restrict,object,optional,JSF_post_api_export_restrictions}
/// an object containing an array of attribute names that will be 
/// included or excluded when returning result documents.
///
/// Not specifying *restrict* will by default return all attributes of each document.
///
/// @RESTSTRUCT{type,JSF_post_api_export_restrictions,string,required,string}
/// has to be be set to either *include* or *exclude* depending on which you want to use
///
/// @RESTSTRUCT{fields,JSF_post_api_export_restrictions,array,required,string}
/// Contains an array of attribute names to *include* or *exclude*. Matching of attribute names
/// for *inclusion* or *exclusion* will be done on the top level only.
/// Specifying names of nested attributes is not supported at the moment.
///
///
/// @RESTQUERYPARAMETERS
///
/// @RESTQUERYPARAM{collection,string,required}
/// The name of the collection to export.
///
/// @RESTDESCRIPTION
/// A call to this method creates a cursor containing all documents in the 
/// specified collection. In contrast to other data-producing APIs, the internal
/// data structures produced by the export API are more lightweight, so it is
/// the preferred way to retrieve all documents from a collection.
/// 
/// Documents are returned in a similar manner as in the `/_api/cursor` REST API. 
/// If all documents of the collection fit into the first batch, then no cursor
/// will be created, and the result object's *hasMore* attribute will be set to
/// *false*. If not all documents fit into the first batch, then the result 
/// object's *hasMore* attribute will be set to *true*, and the *id* attribute
/// of the result will contain a cursor id.
///
/// The order in which the documents are returned is not specified.
///
/// By default, only those documents from the collection will be returned that are
/// stored in the collection's datafiles. Documents that are present in the write-ahead
/// log (WAL) at the time the export is run will not be exported.
/// 
/// To export these documents as well, the caller can issue a WAL flush request
/// before calling the export API or set the *flush* attribute. Setting the *flush*
/// option will trigger a WAL flush before the export so documents get copied from 
/// the WAL to the collection datafiles.
/// 
/// If the result set can be created by the server, the server will respond with
/// *HTTP 201*. The body of the response will contain a JSON object with the
/// result set.
///
/// The returned JSON object has the following properties:
///
/// - *error*: boolean flag to indicate that an error occurred (*false*
///   in this case)
///
/// - *code*: the HTTP status code
///
/// - *result*: an array of result documents (might be empty if the collection was empty)
///
/// - *hasMore*: a boolean indicator whether there are more results
///   available for the cursor on the server
///
/// - *count*: the total number of result documents available (only
///   available if the query was executed with the *count* attribute set)
///
/// - *id*: id of temporary cursor created on the server (optional, see above)
///
/// If the JSON representation is malformed or the query specification is
/// missing from the request, the server will respond with *HTTP 400*.
///
/// The body of the response will contain a JSON object with additional error
/// details. The object has the following attributes:
///
/// - *error*: boolean flag to indicate that an error occurred (*true* in this case)
///
/// - *code*: the HTTP status code
///
/// - *errorNum*: the server error number
///
/// - *errorMessage*: a descriptive error message
///
/// Clients should always delete an export cursor result as early as possible because a
/// lingering export cursor will prevent the underlying collection from being
/// compacted or unloaded. By default, unused cursors will be deleted automatically 
/// after a server-defined idle time, and clients can adjust this idle time by setting
/// the *ttl* value.
///
/// Note: this API is currently not supported on cluster coordinators.
///
/// @RESTRETURNCODES
///
/// @RESTRETURNCODE{201}
/// is returned if the result set can be created by the server.
///
/// @RESTRETURNCODE{400}
/// is returned if the JSON representation is malformed or the query specification is
/// missing from the request.
///
/// @RESTRETURNCODE{404}
/// The server will respond with *HTTP 404* in case a non-existing collection is
/// accessed in the query.
///
/// @RESTRETURNCODE{405}
/// The server will respond with *HTTP 405* if an unsupported HTTP method is used.
///
/// @RESTRETURNCODE{501}
/// The server will respond with *HTTP 501* if this API is called on a cluster
/// coordinator.
///
/// @endDocuBlock
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