aws_sdk_dynamodb/operation/query/
paginator.rs

1// Code generated by software.amazon.smithy.rust.codegen.smithy-rs. DO NOT EDIT.
2/// Paginator for [`Query`](crate::operation::query::Query)
3pub struct QueryPaginator {
4    handle: std::sync::Arc<crate::client::Handle>,
5    builder: crate::operation::query::builders::QueryInputBuilder,
6    stop_on_duplicate_token: bool,
7}
8
9impl QueryPaginator {
10    /// Create a new paginator-wrapper
11    pub(crate) fn new(handle: std::sync::Arc<crate::client::Handle>, builder: crate::operation::query::builders::QueryInputBuilder) -> Self {
12        Self {
13            handle,
14            builder,
15            stop_on_duplicate_token: true,
16        }
17    }
18
19    /// Set the page size
20    ///
21    /// _Note: this method will override any previously set value for `limit`_
22    pub fn page_size(mut self, limit: i32) -> Self {
23        self.builder.limit = ::std::option::Option::Some(limit);
24        self
25    }
26
27    /// Create a flattened paginator
28    ///
29    /// This paginator automatically flattens results using `items`. Queries to the underlying service
30    /// are dispatched lazily.
31    pub fn items(self) -> crate::operation::query::paginator::QueryPaginatorItems {
32        crate::operation::query::paginator::QueryPaginatorItems(self)
33    }
34
35    /// Stop paginating when the service returns the same pagination token twice in a row.
36    ///
37    /// Defaults to true.
38    ///
39    /// For certain operations, it may be useful to continue on duplicate token. For example,
40    /// if an operation is for tailing a log file in real-time, then continuing may be desired.
41    /// This option can be set to `false` to accommodate these use cases.
42    pub fn stop_on_duplicate_token(mut self, stop_on_duplicate_token: bool) -> Self {
43        self.stop_on_duplicate_token = stop_on_duplicate_token;
44        self
45    }
46
47    /// Create the pagination stream
48    ///
49    /// _Note:_ No requests will be dispatched until the stream is used
50    /// (e.g. with the [`.next().await`](aws_smithy_async::future::pagination_stream::PaginationStream::next) method).
51    pub fn send(
52        self,
53    ) -> ::aws_smithy_async::future::pagination_stream::PaginationStream<
54        ::std::result::Result<
55            crate::operation::query::QueryOutput,
56            ::aws_smithy_runtime_api::client::result::SdkError<
57                crate::operation::query::QueryError,
58                ::aws_smithy_runtime_api::client::orchestrator::HttpResponse,
59            >,
60        >,
61    > {
62        // Move individual fields out of self for the borrow checker
63        let builder = self.builder;
64        let handle = self.handle;
65        let runtime_plugins =
66            crate::operation::query::Query::operation_runtime_plugins(handle.runtime_plugins.clone(), &handle.conf, ::std::option::Option::None)
67                .with_operation_plugin(crate::sdk_feature_tracker::paginator::PaginatorFeatureTrackerRuntimePlugin::new());
68        ::aws_smithy_async::future::pagination_stream::PaginationStream::new(::aws_smithy_async::future::pagination_stream::fn_stream::FnStream::new(
69            move |tx| {
70                ::std::boxed::Box::pin(async move {
71                    // Build the input for the first time. If required fields are missing, this is where we'll produce an early error.
72                    let mut input = match builder
73                        .build()
74                        .map_err(::aws_smithy_runtime_api::client::result::SdkError::construction_failure)
75                    {
76                        ::std::result::Result::Ok(input) => input,
77                        ::std::result::Result::Err(e) => {
78                            let _ = tx.send(::std::result::Result::Err(e)).await;
79                            return;
80                        }
81                    };
82                    loop {
83                        let resp = crate::operation::query::Query::orchestrate(&runtime_plugins, input.clone()).await;
84                        // If the input member is None or it was an error
85                        let done = match resp {
86                            ::std::result::Result::Ok(ref resp) => {
87                                let new_token = crate::lens::reflens_query_output_output_last_evaluated_key(resp);
88                                // Pagination is exhausted when the next token is an empty string
89                                let is_empty = new_token.map(|token| token.is_empty()).unwrap_or(true);
90                                if !is_empty && new_token == input.exclusive_start_key.as_ref() && self.stop_on_duplicate_token {
91                                    true
92                                } else {
93                                    input.exclusive_start_key = new_token.cloned();
94                                    is_empty
95                                }
96                            }
97                            ::std::result::Result::Err(_) => true,
98                        };
99                        if tx.send(resp).await.is_err() {
100                            // receiving end was dropped
101                            return;
102                        }
103                        if done {
104                            return;
105                        }
106                    }
107                })
108            },
109        ))
110    }
111}
112
113/// Flattened paginator for `QueryPaginator`
114///
115/// This is created with [`.items()`](QueryPaginator::items)
116pub struct QueryPaginatorItems(QueryPaginator);
117
118impl QueryPaginatorItems {
119    /// Create the pagination stream
120    ///
121    /// _Note_: No requests will be dispatched until the stream is used
122    /// (e.g. with the [`.next().await`](aws_smithy_async::future::pagination_stream::PaginationStream::next) method).
123    ///
124    /// To read the entirety of the paginator, use [`.collect::<Result<Vec<_>, _>()`](aws_smithy_async::future::pagination_stream::PaginationStream::collect).
125    pub fn send(
126        self,
127    ) -> ::aws_smithy_async::future::pagination_stream::PaginationStream<
128        ::std::result::Result<
129            ::std::collections::HashMap<::std::string::String, crate::types::AttributeValue>,
130            ::aws_smithy_runtime_api::client::result::SdkError<
131                crate::operation::query::QueryError,
132                ::aws_smithy_runtime_api::client::orchestrator::HttpResponse,
133            >,
134        >,
135    > {
136        ::aws_smithy_async::future::pagination_stream::TryFlatMap::new(self.0.send())
137            .flat_map(|page| crate::lens::lens_query_output_output_items(page).unwrap_or_default().into_iter())
138    }
139}
aws_sdk_dynamodb/operation/query/paginator.rs

aws_sdk_dynamodb/operation/query/
paginator.rs
