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use bonsaidb::core::connection::Connection;
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use bonsaidb::core::document::{BorrowedDocument, Emit};
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use bonsaidb::core::key::Key;
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use bonsaidb::core::schema::view::map::ViewMappedValue;
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use bonsaidb::core::schema::{
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    Collection, MapReduce, ReduceResult, SerializedCollection, View, ViewMapResult, ViewSchema,
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};
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use bonsaidb::core::Error;
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use bonsaidb::local::config::{Builder, StorageConfiguration};
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use bonsaidb::local::Database;
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use serde::{Deserialize, Serialize};
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// ANCHOR: enum

            

        

            

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#[derive(Serialize, Deserialize, Eq, PartialEq, Debug, Key, Clone)]

            

        

            

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pub enum Category {

            

        

            

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    Rust,

            

        

            

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    Cooking,

            

        

            

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}

            

        

            

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// ANCHOR_END: enum

            

        

            

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// ANCHOR: struct

            

        

            

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#[derive(Serialize, Deserialize, Debug, Collection)]

            

        

            

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#[collection(name = "blog-post", views = [BlogPostsByCategory])]

            

        

            

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pub struct BlogPost {

            

        

            

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    pub title: String,

            

        

            

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    pub body: String,

            

        

            

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    pub category: Option<Category>,

            

        

            

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}

            

        

            

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// ANCHOR_END: struct

            

        

            

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// ANCHOR: view

            

        

            

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#[derive(Debug, Clone, View, ViewSchema)]

            

        

            

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#[view(collection = BlogPost, key = Option<Category>, value = u32, name = "by-category")]

            

        

            

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pub struct BlogPostsByCategory;

            

        

            

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impl MapReduce for BlogPostsByCategory {

            

        

            

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    fn map<'doc>(&self, document: &'doc BorrowedDocument<'_>) -> ViewMapResult<'doc, Self> {

            

        

            

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        let post = BlogPost::document_contents(document)?;

            

        

            

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        document.header.emit_key_and_value(post.category, 1)

            

        

            

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    }

            

        

            

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    fn reduce(

            

        

            

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        &self,

            

        

            

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        mappings: &[ViewMappedValue<Self::View>],

            

        

            

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        _rereduce: bool,

            

        

            

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    ) -> ReduceResult<Self::View> {

            

        

            

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        Ok(mappings.iter().map(|mapping| mapping.value).sum())

            

        

            

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    }

            

        

            

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}

            

        

            

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// ANCHOR_END: view

            

        

            

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#[allow(unused_variables)]

            

        

            

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#[test]

            

        

            

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fn example() -> Result<(), Error> {

            

        

            

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    drop(std::fs::remove_dir_all("example.bonsaidb"));

            

        

            

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    let db = Database::open::<BlogPost>(StorageConfiguration::new("example.bonsaidb"))?;

            

        

            

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    // ANCHOR: query_with_docs

            

        

            

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    let rust_posts = db

            

        

            

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        .view::<BlogPostsByCategory>()

            

        

            

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        .with_key(&Some(Category::Rust))

            

        

            

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        .query_with_docs()?;

            

        

            

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    // ANCHOR_END: query_with_docs

            

        

            

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    // ANCHOR: reduce_one_key

            

        

            

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    let rust_post_count = db

            

        

            

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        .view::<BlogPostsByCategory>()

            

        

            

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        .with_key(&Some(Category::Rust))

            

        

            

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        .reduce()?;

            

        

            

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    // ANCHOR_END: reduce_one_key

            

        

            

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    // ANCHOR: reduce_multiple_keys

            

        

            

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    let total_post_count = db.view::<BlogPostsByCategory>().reduce()?;

            

        

            

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    // ANCHOR_END: reduce_multiple_keys

            

        

            

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    Ok(())

            

        

            

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}