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<a href=#2 id=2 data-nosnippet>2</a>//!
<a href=#3 id=3 data-nosnippet>3</a>//! This module provides comprehensive environment variable handling with type-safe parsing,
<a href=#4 id=4 data-nosnippet>4</a>//! JSON configuration support via our serde module, and parallel processing capabilities.
<a href=#5 id=5 data-nosnippet>5</a>//!
<a href=#6 id=6 data-nosnippet>6</a>//! ## Overview
<a href=#7 id=7 data-nosnippet>7</a>//!
<a href=#8 id=8 data-nosnippet>8</a>//! The `env` module offers:
<a href=#9 id=9 data-nosnippet>9</a>//! - **Basic Environment Access**: Reading variables with defaults and type parsing
<a href=#10 id=10 data-nosnippet>10</a>//! - **JSON Configuration**: Parse complex JSON configs from environment variables
<a href=#11 id=11 data-nosnippet>11</a>//! - **Batch Processing**: Parallel reading of multiple environment variables
<a href=#12 id=12 data-nosnippet>12</a>//! - **Validation**: Check for required environment variables
<a href=#13 id=13 data-nosnippet>13</a>//!
<a href=#14 id=14 data-nosnippet>14</a>//! ## Usage Patterns
<a href=#15 id=15 data-nosnippet>15</a>//!
<a href=#16 id=16 data-nosnippet>16</a>//! ### Basic Environment Variable Access
<a href=#17 id=17 data-nosnippet>17</a>//! ```rust
<a href=#18 id=18 data-nosnippet>18</a>//! use trash_analyzer::sys::env::*;
<a href=#19 id=19 data-nosnippet>19</a>//!
<a href=#20 id=20 data-nosnippet>20</a>//! let home = read_env_var("HOME").unwrap();
<a href=#21 id=21 data-nosnippet>21</a>//! let port: u16 = read_env_var_parse("PORT").unwrap_or(8080);
<a href=#22 id=22 data-nosnippet>22</a>//! let debug = read_env_var_or("DEBUG", "false");
<a href=#23 id=23 data-nosnippet>23</a>//! ```
<a href=#24 id=24 data-nosnippet>24</a>//!
<a href=#25 id=25 data-nosnippet>25</a>//! ### JSON Configuration from Environment
<a href=#26 id=26 data-nosnippet>26</a>//! ```rust
<a href=#27 id=27 data-nosnippet>27</a>//! use trash_analyzer::sys::env::read_env_var_json;
<a href=#28 id=28 data-nosnippet>28</a>//! use serde::{Deserialize, Serialize};
<a href=#29 id=29 data-nosnippet>29</a>//!
<a href=#30 id=30 data-nosnippet>30</a>//! #[derive(Deserialize, Serialize)]
<a href=#31 id=31 data-nosnippet>31</a>//! struct Config { host: String, port: u16 }
<a href=#32 id=32 data-nosnippet>32</a>//!
<a href=#33 id=33 data-nosnippet>33</a>//! let config: Config = read_env_var_json("APP_CONFIG").unwrap();
<a href=#34 id=34 data-nosnippet>34</a>//! ```
<a href=#35 id=35 data-nosnippet>35</a>//!
<a href=#36 id=36 data-nosnippet>36</a>//! ### Batch Processing
<a href=#37 id=37 data-nosnippet>37</a>//! ```rust
<a href=#38 id=38 data-nosnippet>38</a>//! use trash_analyzer::sys::env::read_env_vars_parallel;
<a href=#39 id=39 data-nosnippet>39</a>//!
<a href=#40 id=40 data-nosnippet>40</a>//! let keys = vec!["HOME", "USER", "PATH"];
<a href=#41 id=41 data-nosnippet>41</a>//! let values = read_env_vars_parallel(&keys).unwrap();
<a href=#42 id=42 data-nosnippet>42</a>//! ```
<a href=#43 id=43 data-nosnippet>43</a>
<a href=#44 id=44 data-nosnippet>44</a></span><span class="kw">use </span><span class="kw">crate</span>::parallel;
<a href=#45 id=45 data-nosnippet>45</a><span class="kw">use </span><span class="kw">crate</span>::serde;
<a href=#46 id=46 data-nosnippet>46</a><span class="kw">use </span>::serde::de::DeserializeOwned;
<a href=#47 id=47 data-nosnippet>47</a><span class="kw">use </span>std::collections::HashMap;
<a href=#48 id=48 data-nosnippet>48</a>
<a href=#49 id=49 data-nosnippet>49</a><span class="doccomment">/// Reads an environment variable as a string.
<a href=#50 id=50 data-nosnippet>50</a>///
<a href=#51 id=51 data-nosnippet>51</a>/// # Parameters
<a href=#52 id=52 data-nosnippet>52</a>/// - `key`: The name of the environment variable.
<a href=#53 id=53 data-nosnippet>53</a>///
<a href=#54 id=54 data-nosnippet>54</a>/// # Returns
<a href=#55 id=55 data-nosnippet>55</a>/// - `Ok(String)` containing the value if the variable exists.
<a href=#56 id=56 data-nosnippet>56</a>/// - `Err(std::env::VarError)` if the variable is not set or invalid.
<a href=#57 id=57 data-nosnippet>57</a>///
<a href=#58 id=58 data-nosnippet>58</a>/// # Errors
<a href=#59 id=59 data-nosnippet>59</a>/// Returns a `std::env::VarError` if the environment variable is not set or contains invalid Unicode.
<a href=#60 id=60 data-nosnippet>60</a>///
<a href=#61 id=61 data-nosnippet>61</a>/// # Examples
<a href=#62 id=62 data-nosnippet>62</a>/// ```rust
<a href=#63 id=63 data-nosnippet>63</a>/// use trash_analyzer::sys::env::read_env_var;
<a href=#64 id=64 data-nosnippet>64</a>///
<a href=#65 id=65 data-nosnippet>65</a>/// let home = read_env_var("HOME").unwrap();
<a href=#66 id=66 data-nosnippet>66</a>/// println!("Home directory: {}", home);
<a href=#67 id=67 data-nosnippet>67</a>/// ```
<a href=#68 id=68 data-nosnippet>68</a></span><span class="kw">pub fn </span>read_env_var(key: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><String, std::env::VarError> {
<a href=#69 id=69 data-nosnippet>69</a> std::env::var(key)
<a href=#70 id=70 data-nosnippet>70</a>}
<a href=#71 id=71 data-nosnippet>71</a>
<a href=#72 id=72 data-nosnippet>72</a><span class="doccomment">/// Reads an environment variable with a default value.
<a href=#73 id=73 data-nosnippet>73</a>///
<a href=#74 id=74 data-nosnippet>74</a>/// # Parameters
<a href=#75 id=75 data-nosnippet>75</a>/// - `key`: The name of the environment variable.
<a href=#76 id=76 data-nosnippet>76</a>/// - `default`: The default value to return if the variable is not set.
<a href=#77 id=77 data-nosnippet>77</a>///
<a href=#78 id=78 data-nosnippet>78</a>/// # Returns
<a href=#79 id=79 data-nosnippet>79</a>/// The value of the environment variable or the default.
<a href=#80 id=80 data-nosnippet>80</a>///
<a href=#81 id=81 data-nosnippet>81</a>/// # Examples
<a href=#82 id=82 data-nosnippet>82</a>/// ```rust
<a href=#83 id=83 data-nosnippet>83</a>/// use trash_analyzer::sys::env::read_env_var_or;
<a href=#84 id=84 data-nosnippet>84</a>///
<a href=#85 id=85 data-nosnippet>85</a>/// let port = read_env_var_or("PORT", "8080");
<a href=#86 id=86 data-nosnippet>86</a>/// println!("Port: {}", port);
<a href=#87 id=87 data-nosnippet>87</a>/// ```
<a href=#88 id=88 data-nosnippet>88</a></span><span class="attr">#[must_use]
<a href=#89 id=89 data-nosnippet>89</a></span><span class="kw">pub fn </span>read_env_var_or(key: <span class="kw-2">&</span>str, default: <span class="kw-2">&</span>str) -> String {
<a href=#90 id=90 data-nosnippet>90</a> std::env::var(key).unwrap_or_else(|<span class="kw">_</span>| default.to_string())
<a href=#91 id=91 data-nosnippet>91</a>}
<a href=#92 id=92 data-nosnippet>92</a>
<a href=#93 id=93 data-nosnippet>93</a><span class="doccomment">/// Reads an environment variable and parses it as a type that implements `FromStr`.
<a href=#94 id=94 data-nosnippet>94</a>///
<a href=#95 id=95 data-nosnippet>95</a>/// # Type Parameters
<a href=#96 id=96 data-nosnippet>96</a>/// - `T`: The type to parse the value into, must implement `FromStr`.
<a href=#97 id=97 data-nosnippet>97</a>///
<a href=#98 id=98 data-nosnippet>98</a>/// # Parameters
<a href=#99 id=99 data-nosnippet>99</a>/// - `key`: The name of the environment variable.
<a href=#100 id=100 data-nosnippet>100</a>///
<a href=#101 id=101 data-nosnippet>101</a>/// # Returns
<a href=#102 id=102 data-nosnippet>102</a>/// - `Ok(T)` if parsing succeeds.
<a href=#103 id=103 data-nosnippet>103</a>/// - `Err` if the variable is not set or parsing fails.
<a href=#104 id=104 data-nosnippet>104</a>///
<a href=#105 id=105 data-nosnippet>105</a>/// # Errors
<a href=#106 id=106 data-nosnippet>106</a>/// Returns an error if the environment variable is not set, or if parsing the value fails.
<a href=#107 id=107 data-nosnippet>107</a>///
<a href=#108 id=108 data-nosnippet>108</a>/// # Examples
<a href=#109 id=109 data-nosnippet>109</a>/// ```rust
<a href=#110 id=110 data-nosnippet>110</a>/// use trash_analyzer::sys::env::read_env_var_parse;
<a href=#111 id=111 data-nosnippet>111</a>///
<a href=#112 id=112 data-nosnippet>112</a>/// let port: u16 = read_env_var_parse("PORT").unwrap_or(8080);
<a href=#113 id=113 data-nosnippet>113</a>/// println!("Port: {}", port);
<a href=#114 id=114 data-nosnippet>114</a>/// ```
<a href=#115 id=115 data-nosnippet>115</a></span><span class="kw">pub fn </span>read_env_var_parse<T>(key: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><T, Box<<span class="kw">dyn </span>std::error::Error>>
<a href=#116 id=116 data-nosnippet>116</a><span class="kw">where
<a href=#117 id=117 data-nosnippet>117</a> </span>T: std::str::FromStr,
<a href=#118 id=118 data-nosnippet>118</a> T::Err: std::error::Error + <span class="lifetime">'static</span>,
<a href=#119 id=119 data-nosnippet>119</a>{
<a href=#120 id=120 data-nosnippet>120</a> <span class="kw">let </span>value = std::env::var(key)<span class="question-mark">?</span>;
<a href=#121 id=121 data-nosnippet>121</a> <span class="prelude-val">Ok</span>(value.parse()<span class="question-mark">?</span>)
<a href=#122 id=122 data-nosnippet>122</a>}
<a href=#123 id=123 data-nosnippet>123</a>
<a href=#124 id=124 data-nosnippet>124</a><span class="doccomment">/// Reads an environment variable containing JSON and deserializes it to a type using our serde module.
<a href=#125 id=125 data-nosnippet>125</a>///
<a href=#126 id=126 data-nosnippet>126</a>/// # Type Parameters
<a href=#127 id=127 data-nosnippet>127</a>/// - `T`: The type to deserialize into, must implement `Deserialize`.
<a href=#128 id=128 data-nosnippet>128</a>///
<a href=#129 id=129 data-nosnippet>129</a>/// # Parameters
<a href=#130 id=130 data-nosnippet>130</a>/// - `key`: The name of the environment variable containing JSON.
<a href=#131 id=131 data-nosnippet>131</a>///
<a href=#132 id=132 data-nosnippet>132</a>/// # Returns
<a href=#133 id=133 data-nosnippet>133</a>/// - `Ok(T)` if the variable exists and JSON parsing succeeds.
<a href=#134 id=134 data-nosnippet>134</a>/// - `Err` if the variable is not set or parsing fails.
<a href=#135 id=135 data-nosnippet>135</a>///
<a href=#136 id=136 data-nosnippet>136</a>/// # Errors
<a href=#137 id=137 data-nosnippet>137</a>/// - Returns `std::env::VarError` if the environment variable is not set or contains invalid Unicode.
<a href=#138 id=138 data-nosnippet>138</a>/// - Returns `serde_json::Error` if the JSON parsing fails.
<a href=#139 id=139 data-nosnippet>139</a>///
<a href=#140 id=140 data-nosnippet>140</a>/// # Examples
<a href=#141 id=141 data-nosnippet>141</a>/// ```rust
<a href=#142 id=142 data-nosnippet>142</a>/// use trash_analyzer::sys::env::read_env_var_json;
<a href=#143 id=143 data-nosnippet>143</a>/// use serde::Deserialize;
<a href=#144 id=144 data-nosnippet>144</a>///
<a href=#145 id=145 data-nosnippet>145</a>/// #[derive(Deserialize)]
<a href=#146 id=146 data-nosnippet>146</a>/// struct Config { host: String, port: u16 }
<a href=#147 id=147 data-nosnippet>147</a>///
<a href=#148 id=148 data-nosnippet>148</a>/// let config: Config = read_env_var_json("APP_CONFIG").unwrap();
<a href=#149 id=149 data-nosnippet>149</a>/// ```
<a href=#150 id=150 data-nosnippet>150</a></span><span class="kw">pub fn </span>read_env_var_json<T>(key: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><T, Box<<span class="kw">dyn </span>std::error::Error>>
<a href=#151 id=151 data-nosnippet>151</a><span class="kw">where
<a href=#152 id=152 data-nosnippet>152</a> </span>T: DeserializeOwned,
<a href=#153 id=153 data-nosnippet>153</a>{
<a href=#154 id=154 data-nosnippet>154</a> <span class="kw">let </span>json = std::env::var(key)<span class="question-mark">?</span>;
<a href=#155 id=155 data-nosnippet>155</a> serde::deserialize_from_json(<span class="kw-2">&</span>json).map_err(|e| Box::new(e) <span class="kw">as </span>Box<<span class="kw">dyn </span>std::error::Error>)
<a href=#156 id=156 data-nosnippet>156</a>}
<a href=#157 id=157 data-nosnippet>157</a>
<a href=#158 id=158 data-nosnippet>158</a><span class="doccomment">/// Reads multiple environment variables in parallel using our parallel module.
<a href=#159 id=159 data-nosnippet>159</a>///
<a href=#160 id=160 data-nosnippet>160</a>/// This function processes a collection of environment variable keys concurrently,
<a href=#161 id=161 data-nosnippet>161</a>/// which can improve performance when reading many variables.
<a href=#162 id=162 data-nosnippet>162</a>///
<a href=#163 id=163 data-nosnippet>163</a>/// # Parameters
<a href=#164 id=164 data-nosnippet>164</a>/// - `keys`: A slice of environment variable names to read.
<a href=#165 id=165 data-nosnippet>165</a>///
<a href=#166 id=166 data-nosnippet>166</a>/// # Returns
<a href=#167 id=167 data-nosnippet>167</a>/// A `HashMap` where keys are the variable names and values are the variable values.
<a href=#168 id=168 data-nosnippet>168</a>/// Variables that are not set or contain errors are omitted from the result.
<a href=#169 id=169 data-nosnippet>169</a>///
<a href=#170 id=170 data-nosnippet>170</a>/// # Examples
<a href=#171 id=171 data-nosnippet>171</a>/// ```rust
<a href=#172 id=172 data-nosnippet>172</a>/// use trash_analyzer::sys::env::read_env_vars_parallel;
<a href=#173 id=173 data-nosnippet>173</a>///
<a href=#174 id=174 data-nosnippet>174</a>/// let keys = vec!["HOME", "USER", "PATH"];
<a href=#175 id=175 data-nosnippet>175</a>/// let vars = read_env_vars_parallel(&keys);
<a href=#176 id=176 data-nosnippet>176</a>/// for (key, value) in vars {
<a href=#177 id=177 data-nosnippet>177</a>/// println!("{}: {}", key, value);
<a href=#178 id=178 data-nosnippet>178</a>/// }
<a href=#179 id=179 data-nosnippet>179</a>/// ```
<a href=#180 id=180 data-nosnippet>180</a></span><span class="attr">#[must_use]
<a href=#181 id=181 data-nosnippet>181</a></span><span class="kw">pub fn </span>read_env_vars_parallel(keys: <span class="kw-2">&</span>[<span class="kw-2">&</span>str]) -> HashMap<String, String> {
<a href=#182 id=182 data-nosnippet>182</a> parallel::parallel_map(keys.to_vec(), |key| {
<a href=#183 id=183 data-nosnippet>183</a> std::env::var(key)
<a href=#184 id=184 data-nosnippet>184</a> .ok()
<a href=#185 id=185 data-nosnippet>185</a> .map(|value| (key.to_string(), value))
<a href=#186 id=186 data-nosnippet>186</a> })
<a href=#187 id=187 data-nosnippet>187</a> .into_iter()
<a href=#188 id=188 data-nosnippet>188</a> .flatten()
<a href=#189 id=189 data-nosnippet>189</a> .collect()
<a href=#190 id=190 data-nosnippet>190</a>}
<a href=#191 id=191 data-nosnippet>191</a>
<a href=#192 id=192 data-nosnippet>192</a><span class="doccomment">/// Validates that all required environment variables are set.
<a href=#193 id=193 data-nosnippet>193</a>///
<a href=#194 id=194 data-nosnippet>194</a>/// # Parameters
<a href=#195 id=195 data-nosnippet>195</a>/// - `required_keys`: A slice of environment variable names that must be set.
<a href=#196 id=196 data-nosnippet>196</a>///
<a href=#197 id=197 data-nosnippet>197</a>/// # Returns
<a href=#198 id=198 data-nosnippet>198</a>/// - `Ok(())` if all required variables are set.
<a href=#199 id=199 data-nosnippet>199</a>/// - `Err(Vec<String>)` containing the names of missing variables.
<a href=#200 id=200 data-nosnippet>200</a>///
<a href=#201 id=201 data-nosnippet>201</a>/// # Errors
<a href=#202 id=202 data-nosnippet>202</a>/// Returns a `Vec<String>` containing the names of environment variables that are not set.
<a href=#203 id=203 data-nosnippet>203</a>///
<a href=#204 id=204 data-nosnippet>204</a>/// # Examples
<a href=#205 id=205 data-nosnippet>205</a>/// ```rust
<a href=#206 id=206 data-nosnippet>206</a>/// use trash_analyzer::sys::env::validate_required_env_vars;
<a href=#207 id=207 data-nosnippet>207</a>///
<a href=#208 id=208 data-nosnippet>208</a>/// let required = vec!["HOME", "USER"];
<a href=#209 id=209 data-nosnippet>209</a>/// match validate_required_env_vars(&required) {
<a href=#210 id=210 data-nosnippet>210</a>/// Ok(()) => println!("All required env vars are set"),
<a href=#211 id=211 data-nosnippet>211</a>/// Err(missing) => println!("Missing: {:?}", missing),
<a href=#212 id=212 data-nosnippet>212</a>/// }
<a href=#213 id=213 data-nosnippet>213</a>/// ```
<a href=#214 id=214 data-nosnippet>214</a></span><span class="kw">pub fn </span>validate_required_env_vars(required_keys: <span class="kw-2">&</span>[<span class="kw-2">&</span>str]) -> <span class="prelude-ty">Result</span><(), Vec<String>> {
<a href=#215 id=215 data-nosnippet>215</a> <span class="kw">let </span>missing: Vec<String> = required_keys
<a href=#216 id=216 data-nosnippet>216</a> .iter()
<a href=#217 id=217 data-nosnippet>217</a> .filter_map(|key| std::env::var(key).err().map(|<span class="kw">_</span>| key.to_string()))
<a href=#218 id=218 data-nosnippet>218</a> .collect();
<a href=#219 id=219 data-nosnippet>219</a>
<a href=#220 id=220 data-nosnippet>220</a> <span class="kw">if </span>missing.is_empty() {
<a href=#221 id=221 data-nosnippet>221</a> <span class="prelude-val">Ok</span>(())
<a href=#222 id=222 data-nosnippet>222</a> } <span class="kw">else </span>{
<a href=#223 id=223 data-nosnippet>223</a> <span class="prelude-val">Err</span>(missing)
<a href=#224 id=224 data-nosnippet>224</a> }
<a href=#225 id=225 data-nosnippet>225</a>}</code></pre></div></section></main></body></html>