1 | ;
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2 |
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3 | /*!
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4 | * Module dependencies
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5 | */
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6 |
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7 | const AggregationCursor = require('./cursor/AggregationCursor');
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8 | const Query = require('./query');
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9 | const util = require('util');
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10 | const utils = require('./utils');
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11 | const read = Query.prototype.read;
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12 | const readConcern = Query.prototype.readConcern;
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13 |
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14 | /**
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15 | * Aggregate constructor used for building aggregation pipelines. Do not
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16 | * instantiate this class directly, use [Model.aggregate()](/docs/api.html#model_Model.aggregate) instead.
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17 | *
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18 | * ####Example:
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19 | *
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20 | * const aggregate = Model.aggregate([
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21 | * { $project: { a: 1, b: 1 } },
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22 | * { $skip: 5 }
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23 | * ]);
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24 | *
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25 | * Model.
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26 | * aggregate([{ $match: { age: { $gte: 21 }}}]).
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27 | * unwind('tags').
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28 | * exec(callback);
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29 | *
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30 | * ####Note:
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31 | *
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32 | * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
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33 | * - Mongoose does **not** cast pipeline stages. The below will **not** work unless `_id` is a string in the database
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34 | *
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35 | * ```javascript
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36 | * new Aggregate([{ $match: { _id: '00000000000000000000000a' } }]);
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37 | * // Do this instead to cast to an ObjectId
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38 | * new Aggregate([{ $match: { _id: mongoose.Types.ObjectId('00000000000000000000000a') } }]);
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39 | * ```
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40 | *
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41 | * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/
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42 | * @see driver http://mongodb.github.com/node-mongodb-native/api-generated/collection.html#aggregate
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43 | * @param {Array} [pipeline] aggregation pipeline as an array of objects
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44 | * @api public
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45 | */
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46 |
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47 | function Aggregate(pipeline) {
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48 | this._pipeline = [];
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49 | this._model = undefined;
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50 | this.options = {};
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51 |
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52 | if (arguments.length === 1 && util.isArray(pipeline)) {
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53 | this.append.apply(this, pipeline);
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54 | }
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55 | }
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56 |
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57 | /**
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58 | * Contains options passed down to the [aggregate command](https://docs.mongodb.com/manual/reference/command/aggregate/).
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59 | * Supported options are:
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60 | *
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61 | * - `readPreference`
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62 | * - [`cursor`](./api.html#aggregate_Aggregate-cursor)
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63 | * - [`explain`](./api.html#aggregate_Aggregate-explain)
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64 | * - [`allowDiskUse`](./api.html#aggregate_Aggregate-allowDiskUse)
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65 | * - `maxTimeMS`
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66 | * - `bypassDocumentValidation`
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67 | * - `raw`
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68 | * - `promoteLongs`
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69 | * - `promoteValues`
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70 | * - `promoteBuffers`
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71 | * - [`collation`](./api.html#aggregate_Aggregate-collation)
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72 | * - `comment`
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73 | * - [`session`](./api.html#aggregate_Aggregate-session)
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74 | *
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75 | * @property options
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76 | * @memberOf Aggregate
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77 | * @api public
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78 | */
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79 |
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80 | Aggregate.prototype.options;
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81 |
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82 | /**
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83 | * Binds this aggregate to a model.
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84 | *
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85 | * @param {Model} model the model to which the aggregate is to be bound
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86 | * @return {Aggregate}
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87 | * @api public
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88 | */
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89 |
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90 | Aggregate.prototype.model = function(model) {
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91 | this._model = model;
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92 | if (model.schema != null) {
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93 | if (this.options.readPreference == null &&
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94 | model.schema.options.read != null) {
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95 | this.options.readPreference = model.schema.options.read;
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96 | }
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97 | if (this.options.collation == null &&
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98 | model.schema.options.collation != null) {
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99 | this.options.collation = model.schema.options.collation;
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100 | }
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101 | }
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102 | return this;
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103 | };
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104 |
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105 | /**
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106 | * Appends new operators to this aggregate pipeline
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107 | *
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108 | * ####Examples:
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109 | *
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110 | * aggregate.append({ $project: { field: 1 }}, { $limit: 2 });
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111 | *
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112 | * // or pass an array
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113 | * var pipeline = [{ $match: { daw: 'Logic Audio X' }} ];
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114 | * aggregate.append(pipeline);
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115 | *
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116 | * @param {Object} ops operator(s) to append
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117 | * @return {Aggregate}
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118 | * @api public
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119 | */
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120 |
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121 | Aggregate.prototype.append = function() {
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122 | const args = (arguments.length === 1 && util.isArray(arguments[0]))
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123 | ? arguments[0]
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124 | : utils.args(arguments);
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125 |
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126 | if (!args.every(isOperator)) {
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127 | throw new Error('Arguments must be aggregate pipeline operators');
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128 | }
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129 |
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130 | this._pipeline = this._pipeline.concat(args);
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131 |
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132 | return this;
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133 | };
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134 |
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135 | /**
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136 | * Appends a new $addFields operator to this aggregate pipeline.
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137 | * Requires MongoDB v3.4+ to work
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138 | *
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139 | * ####Examples:
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140 | *
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141 | * // adding new fields based on existing fields
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142 | * aggregate.addFields({
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143 | * newField: '$b.nested'
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144 | * , plusTen: { $add: ['$val', 10]}
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145 | * , sub: {
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146 | * name: '$a'
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147 | * }
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148 | * })
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149 | *
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150 | * // etc
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151 | * aggregate.addFields({ salary_k: { $divide: [ "$salary", 1000 ] } });
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152 | *
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153 | * @param {Object} arg field specification
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154 | * @see $addFields https://docs.mongodb.com/manual/reference/operator/aggregation/addFields/
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155 | * @return {Aggregate}
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156 | * @api public
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157 | */
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158 | Aggregate.prototype.addFields = function(arg) {
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159 | const fields = {};
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160 | if (typeof arg === 'object' && !util.isArray(arg)) {
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161 | Object.keys(arg).forEach(function(field) {
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162 | fields[field] = arg[field];
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163 | });
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164 | } else {
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165 | throw new Error('Invalid addFields() argument. Must be an object');
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166 | }
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167 | return this.append({$addFields: fields});
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168 | };
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169 |
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170 | /**
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171 | * Appends a new $project operator to this aggregate pipeline.
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172 | *
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173 | * Mongoose query [selection syntax](#query_Query-select) is also supported.
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174 | *
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175 | * ####Examples:
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176 | *
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177 | * // include a, include b, exclude _id
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178 | * aggregate.project("a b -_id");
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179 | *
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180 | * // or you may use object notation, useful when
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181 | * // you have keys already prefixed with a "-"
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182 | * aggregate.project({a: 1, b: 1, _id: 0});
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183 | *
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184 | * // reshaping documents
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185 | * aggregate.project({
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186 | * newField: '$b.nested'
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187 | * , plusTen: { $add: ['$val', 10]}
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188 | * , sub: {
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189 | * name: '$a'
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190 | * }
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191 | * })
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192 | *
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193 | * // etc
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194 | * aggregate.project({ salary_k: { $divide: [ "$salary", 1000 ] } });
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195 | *
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196 | * @param {Object|String} arg field specification
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197 | * @see projection http://docs.mongodb.org/manual/reference/aggregation/project/
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198 | * @return {Aggregate}
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199 | * @api public
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200 | */
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201 |
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202 | Aggregate.prototype.project = function(arg) {
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203 | const fields = {};
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204 |
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205 | if (typeof arg === 'object' && !util.isArray(arg)) {
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206 | Object.keys(arg).forEach(function(field) {
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207 | fields[field] = arg[field];
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208 | });
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209 | } else if (arguments.length === 1 && typeof arg === 'string') {
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210 | arg.split(/\s+/).forEach(function(field) {
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211 | if (!field) {
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212 | return;
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213 | }
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214 | const include = field[0] === '-' ? 0 : 1;
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215 | if (include === 0) {
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216 | field = field.substring(1);
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217 | }
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218 | fields[field] = include;
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219 | });
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220 | } else {
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221 | throw new Error('Invalid project() argument. Must be string or object');
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222 | }
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223 |
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224 | return this.append({$project: fields});
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225 | };
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226 |
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227 | /**
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228 | * Appends a new custom $group operator to this aggregate pipeline.
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229 | *
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230 | * ####Examples:
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231 | *
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232 | * aggregate.group({ _id: "$department" });
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233 | *
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234 | * @see $group http://docs.mongodb.org/manual/reference/aggregation/group/
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235 | * @method group
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236 | * @memberOf Aggregate
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237 | * @instance
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238 | * @param {Object} arg $group operator contents
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239 | * @return {Aggregate}
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240 | * @api public
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241 | */
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242 |
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243 | /**
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244 | * Appends a new custom $match operator to this aggregate pipeline.
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245 | *
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246 | * ####Examples:
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247 | *
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248 | * aggregate.match({ department: { $in: [ "sales", "engineering" ] } });
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249 | *
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250 | * @see $match http://docs.mongodb.org/manual/reference/aggregation/match/
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251 | * @method match
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252 | * @memberOf Aggregate
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253 | * @instance
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254 | * @param {Object} arg $match operator contents
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255 | * @return {Aggregate}
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256 | * @api public
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257 | */
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258 |
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259 | /**
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260 | * Appends a new $skip operator to this aggregate pipeline.
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261 | *
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262 | * ####Examples:
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263 | *
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264 | * aggregate.skip(10);
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265 | *
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266 | * @see $skip http://docs.mongodb.org/manual/reference/aggregation/skip/
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267 | * @method skip
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268 | * @memberOf Aggregate
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269 | * @instance
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270 | * @param {Number} num number of records to skip before next stage
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271 | * @return {Aggregate}
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272 | * @api public
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273 | */
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274 |
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275 | /**
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276 | * Appends a new $limit operator to this aggregate pipeline.
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277 | *
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278 | * ####Examples:
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279 | *
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280 | * aggregate.limit(10);
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281 | *
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282 | * @see $limit http://docs.mongodb.org/manual/reference/aggregation/limit/
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283 | * @method limit
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284 | * @memberOf Aggregate
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285 | * @instance
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286 | * @param {Number} num maximum number of records to pass to the next stage
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287 | * @return {Aggregate}
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288 | * @api public
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289 | */
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290 |
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291 | /**
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292 | * Appends a new $geoNear operator to this aggregate pipeline.
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293 | *
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294 | * ####NOTE:
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295 | *
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296 | * **MUST** be used as the first operator in the pipeline.
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297 | *
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298 | * ####Examples:
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299 | *
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300 | * aggregate.near({
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301 | * near: [40.724, -73.997],
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302 | * distanceField: "dist.calculated", // required
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303 | * maxDistance: 0.008,
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304 | * query: { type: "public" },
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305 | * includeLocs: "dist.location",
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306 | * uniqueDocs: true,
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307 | * num: 5
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308 | * });
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309 | *
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310 | * @see $geoNear http://docs.mongodb.org/manual/reference/aggregation/geoNear/
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311 | * @method near
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312 | * @memberOf Aggregate
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313 | * @instance
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314 | * @param {Object} arg
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315 | * @return {Aggregate}
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316 | * @api public
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317 | */
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318 |
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319 | Aggregate.prototype.near = function(arg) {
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320 | const op = {};
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321 | op.$geoNear = arg;
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322 | return this.append(op);
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323 | };
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324 |
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325 | /*!
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326 | * define methods
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327 | */
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328 |
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329 | 'group match skip limit out'.split(' ').forEach(function($operator) {
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330 | Aggregate.prototype[$operator] = function(arg) {
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331 | const op = {};
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332 | op['$' + $operator] = arg;
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333 | return this.append(op);
|
334 | };
|
335 | });
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336 |
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337 | /**
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338 | * Appends new custom $unwind operator(s) to this aggregate pipeline.
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339 | *
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340 | * Note that the `$unwind` operator requires the path name to start with '$'.
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341 | * Mongoose will prepend '$' if the specified field doesn't start '$'.
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342 | *
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343 | * ####Examples:
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344 | *
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345 | * aggregate.unwind("tags");
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346 | * aggregate.unwind("a", "b", "c");
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347 | *
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348 | * @see $unwind http://docs.mongodb.org/manual/reference/aggregation/unwind/
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349 | * @param {String} fields the field(s) to unwind
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350 | * @return {Aggregate}
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351 | * @api public
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352 | */
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353 |
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354 | Aggregate.prototype.unwind = function() {
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355 | const args = utils.args(arguments);
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356 |
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357 | const res = [];
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358 | for (let i = 0; i < args.length; ++i) {
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359 | const arg = args[i];
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360 | if (arg && typeof arg === 'object') {
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361 | res.push({ $unwind: arg });
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362 | } else if (typeof arg === 'string') {
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363 | res.push({
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364 | $unwind: (arg && arg.charAt(0) === '$') ? arg : '$' + arg
|
365 | });
|
366 | } else {
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367 | throw new Error('Invalid arg "' + arg + '" to unwind(), ' +
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368 | 'must be string or object');
|
369 | }
|
370 | }
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371 |
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372 | return this.append.apply(this, res);
|
373 | };
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374 |
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375 | /**
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376 | * Appends a new $replaceRoot operator to this aggregate pipeline.
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377 | *
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378 | * Note that the `$replaceRoot` operator requires field strings to start with '$'.
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379 | * If you are passing in a string Mongoose will prepend '$' if the specified field doesn't start '$'.
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380 | * If you are passing in an object the strings in your expression will not be altered.
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381 | *
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382 | * ####Examples:
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383 | *
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384 | * aggregate.replaceRoot("user");
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385 | *
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386 | * aggregate.replaceRoot({ x: { $concat: ['$this', '$that'] } });
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387 | *
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388 | * @see $replaceRoot https://docs.mongodb.org/manual/reference/operator/aggregation/replaceRoot
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389 | * @param {String|Object} the field or document which will become the new root document
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390 | * @return {Aggregate}
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391 | * @api public
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392 | */
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393 |
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394 | Aggregate.prototype.replaceRoot = function(newRoot) {
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395 | let ret;
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396 |
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397 | if (typeof newRoot === 'string') {
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398 | ret = newRoot.startsWith('$') ? newRoot : '$' + newRoot;
|
399 | } else {
|
400 | ret = newRoot;
|
401 | }
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402 |
|
403 | return this.append({
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404 | $replaceRoot: {
|
405 | newRoot: ret
|
406 | }
|
407 | });
|
408 | };
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409 |
|
410 | /**
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411 | * Appends a new $count operator to this aggregate pipeline.
|
412 | *
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413 | * ####Examples:
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414 | *
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415 | * aggregate.count("userCount");
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416 | *
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417 | * @see $count https://docs.mongodb.org/manual/reference/operator/aggregation/count
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418 | * @param {String} the name of the count field
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419 | * @return {Aggregate}
|
420 | * @api public
|
421 | */
|
422 |
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423 | Aggregate.prototype.count = function(countName) {
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424 | return this.append({ $count: countName });
|
425 | };
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426 |
|
427 | /**
|
428 | * Appends a new $sortByCount operator to this aggregate pipeline. Accepts either a string field name
|
429 | * or a pipeline object.
|
430 | *
|
431 | * Note that the `$sortByCount` operator requires the new root to start with '$'.
|
432 | * Mongoose will prepend '$' if the specified field name doesn't start with '$'.
|
433 | *
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434 | * ####Examples:
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435 | *
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436 | * aggregate.sortByCount('users');
|
437 | * aggregate.sortByCount({ $mergeObjects: [ "$employee", "$business" ] })
|
438 | *
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439 | * @see $sortByCount https://docs.mongodb.com/manual/reference/operator/aggregation/sortByCount/
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440 | * @param {Object|String} arg
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441 | * @return {Aggregate} this
|
442 | * @api public
|
443 | */
|
444 |
|
445 | Aggregate.prototype.sortByCount = function(arg) {
|
446 | if (arg && typeof arg === 'object') {
|
447 | return this.append({ $sortByCount: arg });
|
448 | } else if (typeof arg === 'string') {
|
449 | return this.append({
|
450 | $sortByCount: (arg && arg.charAt(0) === '$') ? arg : '$' + arg
|
451 | });
|
452 | } else {
|
453 | throw new TypeError('Invalid arg "' + arg + '" to sortByCount(), ' +
|
454 | 'must be string or object');
|
455 | }
|
456 | };
|
457 |
|
458 | /**
|
459 | * Appends new custom $lookup operator(s) to this aggregate pipeline.
|
460 | *
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461 | * ####Examples:
|
462 | *
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463 | * aggregate.lookup({ from: 'users', localField: 'userId', foreignField: '_id', as: 'users' });
|
464 | *
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465 | * @see $lookup https://docs.mongodb.org/manual/reference/operator/aggregation/lookup/#pipe._S_lookup
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466 | * @param {Object} options to $lookup as described in the above link
|
467 | * @return {Aggregate}
|
468 | * @api public
|
469 | */
|
470 |
|
471 | Aggregate.prototype.lookup = function(options) {
|
472 | return this.append({$lookup: options});
|
473 | };
|
474 |
|
475 | /**
|
476 | * Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection.
|
477 | *
|
478 | * Note that graphLookup can only consume at most 100MB of memory, and does not allow disk use even if `{ allowDiskUse: true }` is specified.
|
479 | *
|
480 | * #### Examples:
|
481 | * // Suppose we have a collection of courses, where a document might look like `{ _id: 0, name: 'Calculus', prerequisite: 'Trigonometry'}` and `{ _id: 0, name: 'Trigonometry', prerequisite: 'Algebra' }`
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482 | * aggregate.graphLookup({ from: 'courses', startWith: '$prerequisite', connectFromField: 'prerequisite', connectToField: 'name', as: 'prerequisites', maxDepth: 3 }) // this will recursively search the 'courses' collection up to 3 prerequisites
|
483 | *
|
484 | * @see $graphLookup https://docs.mongodb.com/manual/reference/operator/aggregation/graphLookup/#pipe._S_graphLookup
|
485 | * @param {Object} options to $graphLookup as described in the above link
|
486 | * @return {Aggregate}
|
487 | * @api public
|
488 | */
|
489 |
|
490 | Aggregate.prototype.graphLookup = function(options) {
|
491 | const cloneOptions = {};
|
492 | if (options) {
|
493 | if (!utils.isObject(options)) {
|
494 | throw new TypeError('Invalid graphLookup() argument. Must be an object.');
|
495 | }
|
496 |
|
497 | utils.mergeClone(cloneOptions, options);
|
498 | const startWith = cloneOptions.startWith;
|
499 |
|
500 | if (startWith && typeof startWith === 'string') {
|
501 | cloneOptions.startWith = cloneOptions.startWith.charAt(0) === '$' ?
|
502 | cloneOptions.startWith :
|
503 | '$' + cloneOptions.startWith;
|
504 | }
|
505 |
|
506 | }
|
507 | return this.append({ $graphLookup: cloneOptions });
|
508 | };
|
509 |
|
510 | /**
|
511 | * Appends new custom $sample operator(s) to this aggregate pipeline.
|
512 | *
|
513 | * ####Examples:
|
514 | *
|
515 | * aggregate.sample(3); // Add a pipeline that picks 3 random documents
|
516 | *
|
517 | * @see $sample https://docs.mongodb.org/manual/reference/operator/aggregation/sample/#pipe._S_sample
|
518 | * @param {Number} size number of random documents to pick
|
519 | * @return {Aggregate}
|
520 | * @api public
|
521 | */
|
522 |
|
523 | Aggregate.prototype.sample = function(size) {
|
524 | return this.append({$sample: {size: size}});
|
525 | };
|
526 |
|
527 | /**
|
528 | * Appends a new $sort operator to this aggregate pipeline.
|
529 | *
|
530 | * If an object is passed, values allowed are `asc`, `desc`, `ascending`, `descending`, `1`, and `-1`.
|
531 | *
|
532 | * If a string is passed, it must be a space delimited list of path names. The sort order of each path is ascending unless the path name is prefixed with `-` which will be treated as descending.
|
533 | *
|
534 | * ####Examples:
|
535 | *
|
536 | * // these are equivalent
|
537 | * aggregate.sort({ field: 'asc', test: -1 });
|
538 | * aggregate.sort('field -test');
|
539 | *
|
540 | * @see $sort http://docs.mongodb.org/manual/reference/aggregation/sort/
|
541 | * @param {Object|String} arg
|
542 | * @return {Aggregate} this
|
543 | * @api public
|
544 | */
|
545 |
|
546 | Aggregate.prototype.sort = function(arg) {
|
547 | // TODO refactor to reuse the query builder logic
|
548 |
|
549 | const sort = {};
|
550 |
|
551 | if (arg.constructor.name === 'Object') {
|
552 | const desc = ['desc', 'descending', -1];
|
553 | Object.keys(arg).forEach(function(field) {
|
554 | // If sorting by text score, skip coercing into 1/-1
|
555 | if (arg[field] instanceof Object && arg[field].$meta) {
|
556 | sort[field] = arg[field];
|
557 | return;
|
558 | }
|
559 | sort[field] = desc.indexOf(arg[field]) === -1 ? 1 : -1;
|
560 | });
|
561 | } else if (arguments.length === 1 && typeof arg === 'string') {
|
562 | arg.split(/\s+/).forEach(function(field) {
|
563 | if (!field) {
|
564 | return;
|
565 | }
|
566 | const ascend = field[0] === '-' ? -1 : 1;
|
567 | if (ascend === -1) {
|
568 | field = field.substring(1);
|
569 | }
|
570 | sort[field] = ascend;
|
571 | });
|
572 | } else {
|
573 | throw new TypeError('Invalid sort() argument. Must be a string or object.');
|
574 | }
|
575 |
|
576 | return this.append({$sort: sort});
|
577 | };
|
578 |
|
579 | /**
|
580 | * Sets the readPreference option for the aggregation query.
|
581 | *
|
582 | * ####Example:
|
583 | *
|
584 | * Model.aggregate(..).read('primaryPreferred').exec(callback)
|
585 | *
|
586 | * @param {String} pref one of the listed preference options or their aliases
|
587 | * @param {Array} [tags] optional tags for this query
|
588 | * @return {Aggregate} this
|
589 | * @api public
|
590 | * @see mongodb http://docs.mongodb.org/manual/applications/replication/#read-preference
|
591 | * @see driver http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences
|
592 | */
|
593 |
|
594 | Aggregate.prototype.read = function(pref, tags) {
|
595 | if (!this.options) {
|
596 | this.options = {};
|
597 | }
|
598 | read.call(this, pref, tags);
|
599 | return this;
|
600 | };
|
601 |
|
602 | /**
|
603 | * Sets the readConcern level for the aggregation query.
|
604 | *
|
605 | * ####Example:
|
606 | *
|
607 | * Model.aggregate(..).readConcern('majority').exec(callback)
|
608 | *
|
609 | * @param {String} level one of the listed read concern level or their aliases
|
610 | * @see mongodb https://docs.mongodb.com/manual/reference/read-concern/
|
611 | * @return {Aggregate} this
|
612 | * @api public
|
613 | */
|
614 |
|
615 | Aggregate.prototype.readConcern = function(level) {
|
616 | if (!this.options) {
|
617 | this.options = {};
|
618 | }
|
619 | readConcern.call(this, level);
|
620 | return this;
|
621 | };
|
622 |
|
623 | /**
|
624 | * Appends a new $redact operator to this aggregate pipeline.
|
625 | *
|
626 | * If 3 arguments are supplied, Mongoose will wrap them with if-then-else of $cond operator respectively
|
627 | * If `thenExpr` or `elseExpr` is string, make sure it starts with $$, like `$$DESCEND`, `$$PRUNE` or `$$KEEP`.
|
628 | *
|
629 | * ####Example:
|
630 | *
|
631 | * Model.aggregate(...)
|
632 | * .redact({
|
633 | * $cond: {
|
634 | * if: { $eq: [ '$level', 5 ] },
|
635 | * then: '$$PRUNE',
|
636 | * else: '$$DESCEND'
|
637 | * }
|
638 | * })
|
639 | * .exec();
|
640 | *
|
641 | * // $redact often comes with $cond operator, you can also use the following syntax provided by mongoose
|
642 | * Model.aggregate(...)
|
643 | * .redact({ $eq: [ '$level', 5 ] }, '$$PRUNE', '$$DESCEND')
|
644 | * .exec();
|
645 | *
|
646 | * @param {Object} expression redact options or conditional expression
|
647 | * @param {String|Object} [thenExpr] true case for the condition
|
648 | * @param {String|Object} [elseExpr] false case for the condition
|
649 | * @return {Aggregate} this
|
650 | * @see $redact https://docs.mongodb.com/manual/reference/operator/aggregation/redact/
|
651 | * @api public
|
652 | */
|
653 |
|
654 | Aggregate.prototype.redact = function(expression, thenExpr, elseExpr) {
|
655 | if (arguments.length === 3) {
|
656 | if ((typeof thenExpr === 'string' && !thenExpr.startsWith('$$')) ||
|
657 | (typeof elseExpr === 'string' && !elseExpr.startsWith('$$'))) {
|
658 | throw new Error('If thenExpr or elseExpr is string, it must start with $$. e.g. $$DESCEND, $$PRUNE, $$KEEP');
|
659 | }
|
660 |
|
661 | expression = {
|
662 | $cond: {
|
663 | if: expression,
|
664 | then: thenExpr,
|
665 | else: elseExpr
|
666 | }
|
667 | };
|
668 | } else if (arguments.length !== 1) {
|
669 | throw new TypeError('Invalid arguments');
|
670 | }
|
671 |
|
672 | return this.append({$redact: expression});
|
673 | };
|
674 |
|
675 | /**
|
676 | * Execute the aggregation with explain
|
677 | *
|
678 | * ####Example:
|
679 | *
|
680 | * Model.aggregate(..).explain(callback)
|
681 | *
|
682 | * @param {Function} callback
|
683 | * @return {Promise}
|
684 | */
|
685 |
|
686 | Aggregate.prototype.explain = function(callback) {
|
687 | return utils.promiseOrCallback(callback, cb => {
|
688 | if (!this._pipeline.length) {
|
689 | const err = new Error('Aggregate has empty pipeline');
|
690 | return cb(err);
|
691 | }
|
692 |
|
693 | prepareDiscriminatorPipeline(this);
|
694 |
|
695 | this._model.collection.
|
696 | aggregate(this._pipeline, this.options || {}).
|
697 | explain(function(error, result) {
|
698 | if (error) {
|
699 | return cb(error);
|
700 | }
|
701 | cb(null, result);
|
702 | });
|
703 | }, this._model.events);
|
704 | };
|
705 |
|
706 | /**
|
707 | * Sets the allowDiskUse option for the aggregation query (ignored for < 2.6.0)
|
708 | *
|
709 | * ####Example:
|
710 | *
|
711 | * await Model.aggregate([{ $match: { foo: 'bar' } }]).allowDiskUse(true);
|
712 | *
|
713 | * @param {Boolean} value Should tell server it can use hard drive to store data during aggregation.
|
714 | * @param {Array} [tags] optional tags for this query
|
715 | * @see mongodb http://docs.mongodb.org/manual/reference/command/aggregate/
|
716 | */
|
717 |
|
718 | Aggregate.prototype.allowDiskUse = function(value) {
|
719 | this.options.allowDiskUse = value;
|
720 | return this;
|
721 | };
|
722 |
|
723 | /**
|
724 | * Sets the hint option for the aggregation query (ignored for < 3.6.0)
|
725 | *
|
726 | * ####Example:
|
727 | *
|
728 | * Model.aggregate(..).hint({ qty: 1, category: 1 } }).exec(callback)
|
729 | *
|
730 | * @param {Object|String} value a hint object or the index name
|
731 | * @see mongodb http://docs.mongodb.org/manual/reference/command/aggregate/
|
732 | */
|
733 |
|
734 | Aggregate.prototype.hint = function(value) {
|
735 | this.options.hint = value;
|
736 | return this;
|
737 | };
|
738 |
|
739 | /**
|
740 | * Sets the session for this aggregation. Useful for [transactions](/docs/transactions.html).
|
741 | *
|
742 | * ####Example:
|
743 | *
|
744 | * const session = await Model.startSession();
|
745 | * await Model.aggregate(..).session(session);
|
746 | *
|
747 | * @param {ClientSession} session
|
748 | * @see mongodb http://docs.mongodb.org/manual/reference/command/aggregate/
|
749 | */
|
750 |
|
751 | Aggregate.prototype.session = function(session) {
|
752 | if (session == null) {
|
753 | delete this.options.session;
|
754 | } else {
|
755 | this.options.session = session;
|
756 | }
|
757 | return this;
|
758 | };
|
759 |
|
760 | /**
|
761 | * Lets you set arbitrary options, for middleware or plugins.
|
762 | *
|
763 | * ####Example:
|
764 | *
|
765 | * var agg = Model.aggregate(..).option({ allowDiskUse: true }); // Set the `allowDiskUse` option
|
766 | * agg.options; // `{ allowDiskUse: true }`
|
767 | *
|
768 | * @param {Object} options keys to merge into current options
|
769 | * @param [options.maxTimeMS] number limits the time this aggregation will run, see [MongoDB docs on `maxTimeMS`](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/)
|
770 | * @param [options.allowDiskUse] boolean if true, the MongoDB server will use the hard drive to store data during this aggregation
|
771 | * @param [options.collation] object see [`Aggregate.prototype.collation()`](./docs/api.html#aggregate_Aggregate-collation)
|
772 | * @param [options.session] ClientSession see [`Aggregate.prototype.session()`](./docs/api.html#aggregate_Aggregate-session)
|
773 | * @see mongodb http://docs.mongodb.org/manual/reference/command/aggregate/
|
774 | * @return {Aggregate} this
|
775 | * @api public
|
776 | */
|
777 |
|
778 | Aggregate.prototype.option = function(value) {
|
779 | for (const key in value) {
|
780 | this.options[key] = value[key];
|
781 | }
|
782 | return this;
|
783 | };
|
784 |
|
785 | /**
|
786 | * Sets the cursor option option for the aggregation query (ignored for < 2.6.0).
|
787 | * Note the different syntax below: .exec() returns a cursor object, and no callback
|
788 | * is necessary.
|
789 | *
|
790 | * ####Example:
|
791 | *
|
792 | * var cursor = Model.aggregate(..).cursor({ batchSize: 1000 }).exec();
|
793 | * cursor.each(function(error, doc) {
|
794 | * // use doc
|
795 | * });
|
796 | *
|
797 | * @param {Object} options
|
798 | * @param {Number} options.batchSize set the cursor batch size
|
799 | * @param {Boolean} [options.useMongooseAggCursor] use experimental mongoose-specific aggregation cursor (for `eachAsync()` and other query cursor semantics)
|
800 | * @return {Aggregate} this
|
801 | * @api public
|
802 | * @see mongodb http://mongodb.github.io/node-mongodb-native/2.0/api/AggregationCursor.html
|
803 | */
|
804 |
|
805 | Aggregate.prototype.cursor = function(options) {
|
806 | if (!this.options) {
|
807 | this.options = {};
|
808 | }
|
809 | this.options.cursor = options || {};
|
810 | return this;
|
811 | };
|
812 |
|
813 | /**
|
814 | * Sets an option on this aggregation. This function will be deprecated in a
|
815 | * future release. Use the [`cursor()`](./api.html#aggregate_Aggregate-cursor),
|
816 | * [`collation()`](./api.html#aggregate_Aggregate-collation), etc. helpers to
|
817 | * set individual options, or access `agg.options` directly.
|
818 | *
|
819 | * Note that MongoDB aggregations [do **not** support the `noCursorTimeout` flag](https://jira.mongodb.org/browse/SERVER-6036),
|
820 | * if you try setting that flag with this function you will get a "unrecognized field 'noCursorTimeout'" error.
|
821 | *
|
822 | * @param {String} flag
|
823 | * @param {Boolean} value
|
824 | * @return {Aggregate} this
|
825 | * @api public
|
826 | * @deprecated Use [`.option()`](api.html#aggregate_Aggregate-option) instead. Note that MongoDB aggregations do **not** support a `noCursorTimeout` option.
|
827 | */
|
828 |
|
829 | Aggregate.prototype.addCursorFlag = util.deprecate(function(flag, value) {
|
830 | if (!this.options) {
|
831 | this.options = {};
|
832 | }
|
833 | this.options[flag] = value;
|
834 | return this;
|
835 | }, 'Mongoose: `Aggregate#addCursorFlag()` is deprecated, use `option()` instead');
|
836 |
|
837 | /**
|
838 | * Adds a collation
|
839 | *
|
840 | * ####Example:
|
841 | *
|
842 | * Model.aggregate(..).collation({ locale: 'en_US', strength: 1 }).exec();
|
843 | *
|
844 | * @param {Object} collation options
|
845 | * @return {Aggregate} this
|
846 | * @api public
|
847 | * @see mongodb http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#aggregate
|
848 | */
|
849 |
|
850 | Aggregate.prototype.collation = function(collation) {
|
851 | if (!this.options) {
|
852 | this.options = {};
|
853 | }
|
854 | this.options.collation = collation;
|
855 | return this;
|
856 | };
|
857 |
|
858 | /**
|
859 | * Combines multiple aggregation pipelines.
|
860 | *
|
861 | * ####Example:
|
862 | *
|
863 | * Model.aggregate(...)
|
864 | * .facet({
|
865 | * books: [{ groupBy: '$author' }],
|
866 | * price: [{ $bucketAuto: { groupBy: '$price', buckets: 2 } }]
|
867 | * })
|
868 | * .exec();
|
869 | *
|
870 | * // Output: { books: [...], price: [{...}, {...}] }
|
871 | *
|
872 | * @param {Object} facet options
|
873 | * @return {Aggregate} this
|
874 | * @see $facet https://docs.mongodb.com/v3.4/reference/operator/aggregation/facet/
|
875 | * @api public
|
876 | */
|
877 |
|
878 | Aggregate.prototype.facet = function(options) {
|
879 | return this.append({$facet: options});
|
880 | };
|
881 |
|
882 | /**
|
883 | * Returns the current pipeline
|
884 | *
|
885 | * ####Example:
|
886 | *
|
887 | * MyModel.aggregate().match({ test: 1 }).pipeline(); // [{ $match: { test: 1 } }]
|
888 | *
|
889 | * @return {Array}
|
890 | * @api public
|
891 | */
|
892 |
|
893 |
|
894 | Aggregate.prototype.pipeline = function() {
|
895 | return this._pipeline;
|
896 | };
|
897 |
|
898 | /**
|
899 | * Executes the aggregate pipeline on the currently bound Model.
|
900 | *
|
901 | * ####Example:
|
902 | *
|
903 | * aggregate.exec(callback);
|
904 | *
|
905 | * // Because a promise is returned, the `callback` is optional.
|
906 | * var promise = aggregate.exec();
|
907 | * promise.then(..);
|
908 | *
|
909 | * @see Promise #promise_Promise
|
910 | * @param {Function} [callback]
|
911 | * @return {Promise}
|
912 | * @api public
|
913 | */
|
914 |
|
915 | Aggregate.prototype.exec = function(callback) {
|
916 | if (!this._model) {
|
917 | throw new Error('Aggregate not bound to any Model');
|
918 | }
|
919 | const model = this._model;
|
920 | const options = utils.clone(this.options || {});
|
921 | const pipeline = this._pipeline;
|
922 | const collection = this._model.collection;
|
923 |
|
924 | if (options && options.cursor) {
|
925 | return new AggregationCursor(this);
|
926 | }
|
927 |
|
928 | return utils.promiseOrCallback(callback, cb => {
|
929 | if (!pipeline.length) {
|
930 | const err = new Error('Aggregate has empty pipeline');
|
931 | return cb(err);
|
932 | }
|
933 |
|
934 | prepareDiscriminatorPipeline(this);
|
935 |
|
936 | model.hooks.execPre('aggregate', this, error => {
|
937 | if (error) {
|
938 | const _opts = { error: error };
|
939 | return model.hooks.execPost('aggregate', this, [null], _opts, error => {
|
940 | cb(error);
|
941 | });
|
942 | }
|
943 |
|
944 | collection.aggregate(pipeline, options, (error, cursor) => {
|
945 | if (error) {
|
946 | const _opts = { error: error };
|
947 | return model.hooks.execPost('aggregate', this, [null], _opts, error => {
|
948 | if (error) {
|
949 | return cb(error);
|
950 | }
|
951 | return cb(null);
|
952 | });
|
953 | }
|
954 | cursor.toArray((error, result) => {
|
955 | const _opts = { error: error };
|
956 | model.hooks.execPost('aggregate', this, [result], _opts, (error, result) => {
|
957 | if (error) {
|
958 | return cb(error);
|
959 | }
|
960 |
|
961 | cb(null, result);
|
962 | });
|
963 | });
|
964 | });
|
965 | });
|
966 | }, model.events);
|
967 | };
|
968 |
|
969 | /**
|
970 | * Provides promise for aggregate.
|
971 | *
|
972 | * ####Example:
|
973 | *
|
974 | * Model.aggregate(..).then(successCallback, errorCallback);
|
975 | *
|
976 | * @see Promise #promise_Promise
|
977 | * @param {Function} [resolve] successCallback
|
978 | * @param {Function} [reject] errorCallback
|
979 | * @return {Promise}
|
980 | */
|
981 | Aggregate.prototype.then = function(resolve, reject) {
|
982 | return this.exec().then(resolve, reject);
|
983 | };
|
984 |
|
985 | /**
|
986 | * Executes the query returning a `Promise` which will be
|
987 | * resolved with either the doc(s) or rejected with the error.
|
988 | * Like [`.then()`](#query_Query-then), but only takes a rejection handler.
|
989 | *
|
990 | * @param {Function} [reject]
|
991 | * @return {Promise}
|
992 | * @api public
|
993 | */
|
994 |
|
995 | Aggregate.prototype.catch = function(reject) {
|
996 | return this.exec().then(null, reject);
|
997 | };
|
998 |
|
999 | /**
|
1000 | * Returns an asyncIterator for use with [`for/await/of` loops](http://bit.ly/async-iterators)
|
1001 | * This function *only* works for `find()` queries.
|
1002 | * You do not need to call this function explicitly, the JavaScript runtime
|
1003 | * will call it for you.
|
1004 | *
|
1005 | * ####Example
|
1006 | *
|
1007 | * for await (const doc of Model.find().sort({ name: 1 })) {
|
1008 | * console.log(doc.name);
|
1009 | * }
|
1010 | *
|
1011 | * Node.js 10.x supports async iterators natively without any flags. You can
|
1012 | * enable async iterators in Node.js 8.x using the [`--harmony_async_iteration` flag](https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187).
|
1013 | *
|
1014 | * **Note:** This function is not if `Symbol.asyncIterator` is undefined. If
|
1015 | * `Symbol.asyncIterator` is undefined, that means your Node.js version does not
|
1016 | * support async iterators.
|
1017 | *
|
1018 | * @method Symbol.asyncIterator
|
1019 | * @memberOf Aggregate
|
1020 | * @instance
|
1021 | * @api public
|
1022 | */
|
1023 |
|
1024 | if (Symbol.asyncIterator != null) {
|
1025 | Aggregate.prototype[Symbol.asyncIterator] = function() {
|
1026 | return this.cursor({ useMongooseAggCursor: true }).
|
1027 | exec().
|
1028 | transformNull().
|
1029 | map(doc => {
|
1030 | return doc == null ? { done: true } : { value: doc, done: false };
|
1031 | });
|
1032 | };
|
1033 | }
|
1034 |
|
1035 | /*!
|
1036 | * Helpers
|
1037 | */
|
1038 |
|
1039 | /**
|
1040 | * Checks whether an object is likely a pipeline operator
|
1041 | *
|
1042 | * @param {Object} obj object to check
|
1043 | * @return {Boolean}
|
1044 | * @api private
|
1045 | */
|
1046 |
|
1047 | function isOperator(obj) {
|
1048 | if (typeof obj !== 'object') {
|
1049 | return false;
|
1050 | }
|
1051 |
|
1052 | const k = Object.keys(obj);
|
1053 |
|
1054 | return k.length === 1 && k.some(key => { return key[0] === '$'; });
|
1055 | }
|
1056 |
|
1057 | /*!
|
1058 | * Adds the appropriate `$match` pipeline step to the top of an aggregate's
|
1059 | * pipeline, should it's model is a non-root discriminator type. This is
|
1060 | * analogous to the `prepareDiscriminatorCriteria` function in `lib/query.js`.
|
1061 | *
|
1062 | * @param {Aggregate} aggregate Aggregate to prepare
|
1063 | */
|
1064 |
|
1065 | Aggregate._prepareDiscriminatorPipeline = prepareDiscriminatorPipeline;
|
1066 |
|
1067 | function prepareDiscriminatorPipeline(aggregate) {
|
1068 | const schema = aggregate._model.schema;
|
1069 | const discriminatorMapping = schema && schema.discriminatorMapping;
|
1070 |
|
1071 | if (discriminatorMapping && !discriminatorMapping.isRoot) {
|
1072 | const originalPipeline = aggregate._pipeline;
|
1073 | const discriminatorKey = discriminatorMapping.key;
|
1074 | const discriminatorValue = discriminatorMapping.value;
|
1075 |
|
1076 | // If the first pipeline stage is a match and it doesn't specify a `__t`
|
1077 | // key, add the discriminator key to it. This allows for potential
|
1078 | // aggregation query optimizations not to be disturbed by this feature.
|
1079 | if (originalPipeline[0] && originalPipeline[0].$match && !originalPipeline[0].$match[discriminatorKey]) {
|
1080 | originalPipeline[0].$match[discriminatorKey] = discriminatorValue;
|
1081 | // `originalPipeline` is a ref, so there's no need for
|
1082 | // aggregate._pipeline = originalPipeline
|
1083 | } else if (originalPipeline[0] && originalPipeline[0].$geoNear) {
|
1084 | originalPipeline[0].$geoNear.query =
|
1085 | originalPipeline[0].$geoNear.query || {};
|
1086 | originalPipeline[0].$geoNear.query[discriminatorKey] = discriminatorValue;
|
1087 | } else {
|
1088 | const match = {};
|
1089 | match[discriminatorKey] = discriminatorValue;
|
1090 | aggregate._pipeline.unshift({ $match: match });
|
1091 | }
|
1092 | }
|
1093 | }
|
1094 |
|
1095 | /*!
|
1096 | * Exports
|
1097 | */
|
1098 |
|
1099 | module.exports = Aggregate;
|