Spring Data 中的 MongoDB $addField 和 $indexOfArray [英] MongoDB $addField and $indexOfArray in Spring Data

问题描述

我正在尝试根据 Asya Kamsky 的 post:

I am trying to implement a custom sort with MongoDB and Spring Data according to Asya Kamsky's post:

List<AggregationOperation> operations = new ArrayList<>();

operations.add(Aggregation.addFields().addField("scorrrz")
        .withValueOfExpression("{ \"$indexOfArray\" : [ [\"John\", \"Bill\"], \"$name\" ] }").build());

当我尝试执行此操作时，我得到:

When I try to execute this, I get:

ERROR a.insurance.misc.ErrorAttributes - /api/v1/insurance/opportunity/all
org.springframework.expression.spel.SpelParseException: Expression [{ "$indexOfArray" : [ ["John", "Bill"], "$name" ] }] @29: EL1043E: Unexpected token. Expected 'rsquare(])' but was 'comma(,)'

这不是正确的语法吗?如何使用 Spring Data 做到这一点?

Is this not the right syntaxt? How can this be done with Spring Data?

推荐答案

Collection<String> nameList = Arrays.asList("John", "Bill");

Aggregation agg = newAggregation(
                    addFields()
                     .addField("scorrrz").withValue(arrayOf(nameList).indexOf("$name"))
                     .build()
);

聚合的投影是一个带有 $indexOfArray 聚合数组操作的 $addFields 阶段.这将返回一个字段scorrrz，当没有匹配时，它将具有索引值或-1.这在 Spring Boot v2.3.10 和 MongoDB v4.2.8 上运行良好.

The aggregation's projection is an $addFields stage with a $indexOfArray aggregation array operation. This will return a field scorrrz, and it will have index value or -1 when there is no match. This ran okay with Spring Boot v2.3.10 and MongoDB v4.2.8.

运行此聚合将管道 agg 传递给 MongoTemplate#aggregate 方法.

The run this aggregation pass the pipeline agg to the MongoTemplate#aggregate method.

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