<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `actix-session/src/storage/interface.rs`."><title>interface.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><link rel="stylesheet" href="../../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../../static.files/rustdoc-e935ef01ae1c1829.css"><meta name="rustdoc-vars" data-root-path="../../../" data-static-root-path="../../../static.files/" data-current-crate="actix_session" data-themes="" data-resource-suffix="" data-rustdoc-version="1.78.0-nightly (a165f1f65 2024-03-12)" data-channel="nightly" data-search-js="search-dd67cee4cfa65049.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../../static.files/storage-4c98445ec4002617.js"></script><script defer src="../../../static.files/src-script-e66d777a5a92e9b2.js"></script><script defer src="../../../src-files.js"></script><script defer src="../../../static.files/main-12cf3b4f4f9dc36d.js"></script><noscript><link rel="stylesheet" href="../../../static.files/noscript-04d5337699b92874.css"></noscript><link rel="icon" href="https://actix.rs/favicon.ico"></head><body class="rustdoc src"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="src-sidebar-title">
            <h2>Files</h2></div></nav><div class="sidebar-resizer"></div>
    <main><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../../../actix_session/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../../../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><div data-nosnippet><pre class="src-line-numbers"><a href="#1" id="1">1</a>
<a href="#2" id="2">2</a>
<a href="#3" id="3">3</a>
<a href="#4" id="4">4</a>
<a href="#5" id="5">5</a>
<a href="#6" id="6">6</a>
<a href="#7" id="7">7</a>
<a href="#8" id="8">8</a>
<a href="#9" id="9">9</a>
<a href="#10" id="10">10</a>
<a href="#11" id="11">11</a>
<a href="#12" id="12">12</a>
<a href="#13" id="13">13</a>
<a href="#14" id="14">14</a>
<a href="#15" id="15">15</a>
<a href="#16" id="16">16</a>
<a href="#17" id="17">17</a>
<a href="#18" id="18">18</a>
<a href="#19" id="19">19</a>
<a href="#20" id="20">20</a>
<a href="#21" id="21">21</a>
<a href="#22" id="22">22</a>
<a href="#23" id="23">23</a>
<a href="#24" id="24">24</a>
<a href="#25" id="25">25</a>
<a href="#26" id="26">26</a>
<a href="#27" id="27">27</a>
<a href="#28" id="28">28</a>
<a href="#29" id="29">29</a>
<a href="#30" id="30">30</a>
<a href="#31" id="31">31</a>
<a href="#32" id="32">32</a>
<a href="#33" id="33">33</a>
<a href="#34" id="34">34</a>
<a href="#35" id="35">35</a>
<a href="#36" id="36">36</a>
<a href="#37" id="37">37</a>
<a href="#38" id="38">38</a>
<a href="#39" id="39">39</a>
<a href="#40" id="40">40</a>
<a href="#41" id="41">41</a>
<a href="#42" id="42">42</a>
<a href="#43" id="43">43</a>
<a href="#44" id="44">44</a>
<a href="#45" id="45">45</a>
<a href="#46" id="46">46</a>
<a href="#47" id="47">47</a>
<a href="#48" id="48">48</a>
<a href="#49" id="49">49</a>
<a href="#50" id="50">50</a>
<a href="#51" id="51">51</a>
<a href="#52" id="52">52</a>
<a href="#53" id="53">53</a>
<a href="#54" id="54">54</a>
<a href="#55" id="55">55</a>
<a href="#56" id="56">56</a>
<a href="#57" id="57">57</a>
<a href="#58" id="58">58</a>
<a href="#59" id="59">59</a>
<a href="#60" id="60">60</a>
<a href="#61" id="61">61</a>
<a href="#62" id="62">62</a>
<a href="#63" id="63">63</a>
<a href="#64" id="64">64</a>
<a href="#65" id="65">65</a>
<a href="#66" id="66">66</a>
<a href="#67" id="67">67</a>
<a href="#68" id="68">68</a>
<a href="#69" id="69">69</a>
<a href="#70" id="70">70</a>
<a href="#71" id="71">71</a>
<a href="#72" id="72">72</a>
<a href="#73" id="73">73</a>
<a href="#74" id="74">74</a>
<a href="#75" id="75">75</a>
<a href="#76" id="76">76</a>
<a href="#77" id="77">77</a>
<a href="#78" id="78">78</a>
<a href="#79" id="79">79</a>
<a href="#80" id="80">80</a>
<a href="#81" id="81">81</a>
<a href="#82" id="82">82</a>
<a href="#83" id="83">83</a>
<a href="#84" id="84">84</a>
<a href="#85" id="85">85</a>
<a href="#86" id="86">86</a>
<a href="#87" id="87">87</a>
<a href="#88" id="88">88</a>
<a href="#89" id="89">89</a>
<a href="#90" id="90">90</a>
<a href="#91" id="91">91</a>
<a href="#92" id="92">92</a>
<a href="#93" id="93">93</a>
<a href="#94" id="94">94</a>
<a href="#95" id="95">95</a>
<a href="#96" id="96">96</a>
<a href="#97" id="97">97</a>
<a href="#98" id="98">98</a>
<a href="#99" id="99">99</a>
<a href="#100" id="100">100</a>
<a href="#101" id="101">101</a>
<a href="#102" id="102">102</a>
<a href="#103" id="103">103</a>
<a href="#104" id="104">104</a>
<a href="#105" id="105">105</a>
<a href="#106" id="106">106</a>
<a href="#107" id="107">107</a>
<a href="#108" id="108">108</a>
<a href="#109" id="109">109</a>
<a href="#110" id="110">110</a>
<a href="#111" id="111">111</a>
<a href="#112" id="112">112</a>
<a href="#113" id="113">113</a>
</pre></div><pre class="rust"><code><span class="kw">use </span>std::{collections::HashMap, future::Future};

<span class="kw">use </span>actix_web::cookie::time::Duration;
<span class="kw">use </span>derive_more::Display;

<span class="kw">use </span><span class="kw">super</span>::SessionKey;

<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">type </span>SessionState = HashMap&lt;String, String&gt;;

<span class="doccomment">/// The interface to retrieve and save the current session data from/to the chosen storage backend.
///
/// You can provide your own custom session store backend by implementing this trait.
</span><span class="kw">pub trait </span>SessionStore {
    <span class="doccomment">/// Loads the session state associated to a session key.
    </span><span class="kw">fn </span>load(
        <span class="kw-2">&amp;</span><span class="self">self</span>,
        session_key: <span class="kw-2">&amp;</span>SessionKey,
    ) -&gt; <span class="kw">impl </span>Future&lt;Output = <span class="prelude-ty">Result</span>&lt;<span class="prelude-ty">Option</span>&lt;SessionState&gt;, LoadError&gt;&gt;;

    <span class="doccomment">/// Persist the session state for a newly created session.
    ///
    /// Returns the corresponding session key.
    </span><span class="kw">fn </span>save(
        <span class="kw-2">&amp;</span><span class="self">self</span>,
        session_state: SessionState,
        ttl: <span class="kw-2">&amp;</span>Duration,
    ) -&gt; <span class="kw">impl </span>Future&lt;Output = <span class="prelude-ty">Result</span>&lt;SessionKey, SaveError&gt;&gt;;

    <span class="doccomment">/// Updates the session state associated to a pre-existing session key.
    </span><span class="kw">fn </span>update(
        <span class="kw-2">&amp;</span><span class="self">self</span>,
        session_key: SessionKey,
        session_state: SessionState,
        ttl: <span class="kw-2">&amp;</span>Duration,
    ) -&gt; <span class="kw">impl </span>Future&lt;Output = <span class="prelude-ty">Result</span>&lt;SessionKey, UpdateError&gt;&gt;;

    <span class="doccomment">/// Updates the TTL of the session state associated to a pre-existing session key.
    </span><span class="kw">fn </span>update_ttl(
        <span class="kw-2">&amp;</span><span class="self">self</span>,
        session_key: <span class="kw-2">&amp;</span>SessionKey,
        ttl: <span class="kw-2">&amp;</span>Duration,
    ) -&gt; <span class="kw">impl </span>Future&lt;Output = <span class="prelude-ty">Result</span>&lt;(), anyhow::Error&gt;&gt;;

    <span class="doccomment">/// Deletes a session from the store.
    </span><span class="kw">fn </span>delete(<span class="kw-2">&amp;</span><span class="self">self</span>, session_key: <span class="kw-2">&amp;</span>SessionKey) -&gt; <span class="kw">impl </span>Future&lt;Output = <span class="prelude-ty">Result</span>&lt;(), anyhow::Error&gt;&gt;;
}

<span class="comment">// We cannot derive the `Error` implementation using `derive_more` for our custom errors:
// `derive_more`'s `#[error(source)]` attribute requires the source implement the `Error` trait,
// while it's actually enough for it to be able to produce a reference to a dyn Error.

</span><span class="doccomment">/// Possible failures modes for [`SessionStore::load`].
</span><span class="attr">#[derive(Debug, Display)]
</span><span class="kw">pub enum </span>LoadError {
    <span class="doccomment">/// Failed to deserialize session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Failed to deserialize session state"</span>)]
    </span>Deserialization(anyhow::Error),

    <span class="doccomment">/// Something went wrong when retrieving the session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Something went wrong when retrieving the session state"</span>)]
    </span>Other(anyhow::Error),
}

<span class="kw">impl </span>std::error::Error <span class="kw">for </span>LoadError {
    <span class="kw">fn </span>source(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span>(<span class="kw">dyn </span>std::error::Error + <span class="lifetime">'static</span>)&gt; {
        <span class="kw">match </span><span class="self">self </span>{
            <span class="self">Self</span>::Deserialization(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
            <span class="self">Self</span>::Other(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
        }
    }
}

<span class="doccomment">/// Possible failures modes for [`SessionStore::save`].
</span><span class="attr">#[derive(Debug, Display)]
</span><span class="kw">pub enum </span>SaveError {
    <span class="doccomment">/// Failed to serialize session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Failed to serialize session state"</span>)]
    </span>Serialization(anyhow::Error),

    <span class="doccomment">/// Something went wrong when persisting the session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Something went wrong when persisting the session state"</span>)]
    </span>Other(anyhow::Error),
}

<span class="kw">impl </span>std::error::Error <span class="kw">for </span>SaveError {
    <span class="kw">fn </span>source(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span>(<span class="kw">dyn </span>std::error::Error + <span class="lifetime">'static</span>)&gt; {
        <span class="kw">match </span><span class="self">self </span>{
            <span class="self">Self</span>::Serialization(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
            <span class="self">Self</span>::Other(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
        }
    }
}

<span class="attr">#[derive(Debug, Display)]
</span><span class="doccomment">/// Possible failures modes for [`SessionStore::update`].
</span><span class="kw">pub enum </span>UpdateError {
    <span class="doccomment">/// Failed to serialize session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Failed to serialize session state"</span>)]
    </span>Serialization(anyhow::Error),

    <span class="doccomment">/// Something went wrong when updating the session state.
    </span><span class="attr">#[display(fmt = <span class="string">"Something went wrong when updating the session state."</span>)]
    </span>Other(anyhow::Error),
}

<span class="kw">impl </span>std::error::Error <span class="kw">for </span>UpdateError {
    <span class="kw">fn </span>source(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span>(<span class="kw">dyn </span>std::error::Error + <span class="lifetime">'static</span>)&gt; {
        <span class="kw">match </span><span class="self">self </span>{
            <span class="self">Self</span>::Serialization(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
            <span class="self">Self</span>::Other(err) =&gt; <span class="prelude-val">Some</span>(err.as_ref()),
        }
    }
}
</code></pre></div></section></main></body></html>