如何在 Spring Boot 的 YML 文件中创建条件属性? [英] How make a conditional property in a YML file in Spring Boot?

问题描述

我希望能够有这样的东西:

I want to be able to have something like:

some-property: '#{${ENV_VAR_1:} == "someVal" ? boo + "someVal" : ${ENV_VAR_1}}'

这样的事情有可能吗?

当我当前尝试此操作时，出现错误:

When I try this currently, I get the error:

Caused by: java.lang.IllegalArgumentException: Operand must not be null在 org.springframework.util.Assert.notNull(Assert.java:198) ~[spring-core-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.ast.SpelNodeImpl.(SpelNodeImpl.java:77) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.ast.Ternary.(Ternary.java:40) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.standard.InternalSpelExpressionParser.eatExpression(InternalSpelExpressionParser.java:183) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.standard.InternalSpelExpressionParser.doParseExpression(InternalSpelExpressionParser.java:131) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.standard.SpelExpressionParser.doParseExpression(SpelExpressionParser.java:61) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.spel.standard.SpelExpressionParser.doParseExpression(SpelExpressionParser.java:33) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.common.TemplateAwareExpressionParser.parseExpressions(TemplateAwareExpressionParser.java:121) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.common.TemplateAwareExpressionParser.parseTemplate(TemplateAwareExpressionParser.java:62) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.expression.common.TemplateAwareExpressionParser.parseExpression(TemplateAwareExpressionParser.java:49) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE]在 org.springframework.context.expression.StandardBeanExpressionResolver.evaluate(StandardBeanExpressionResolver.java:142) ~[spring-context-5.1.3.RELEASE.jar:5.1.3.RELEASE]...省略了 51 个常用帧

Caused by: java.lang.IllegalArgumentException: Operand must not be null at org.springframework.util.Assert.notNull(Assert.java:198) ~[spring-core-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.ast.SpelNodeImpl.(SpelNodeImpl.java:77) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.ast.Ternary.(Ternary.java:40) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.standard.InternalSpelExpressionParser.eatExpression(InternalSpelExpressionParser.java:183) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.standard.InternalSpelExpressionParser.doParseExpression(InternalSpelExpressionParser.java:131) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.standard.SpelExpressionParser.doParseExpression(SpelExpressionParser.java:61) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.spel.standard.SpelExpressionParser.doParseExpression(SpelExpressionParser.java:33) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.common.TemplateAwareExpressionParser.parseExpressions(TemplateAwareExpressionParser.java:121) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.common.TemplateAwareExpressionParser.parseTemplate(TemplateAwareExpressionParser.java:62) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.expression.common.TemplateAwareExpressionParser.parseExpression(TemplateAwareExpressionParser.java:49) ~[spring-expression-5.1.3.RELEASE.jar:5.1.3.RELEASE] at org.springframework.context.expression.StandardBeanExpressionResolver.evaluate(StandardBeanExpressionResolver.java:142) ~[spring-context-5.1.3.RELEASE.jar:5.1.3.RELEASE] ... 51 common frames omitted

推荐答案

你也可以像下面这样使用 YML 中的 SPEL -

you can also do like below using SPEL in YML -

some-property: '#{"${ENV_VAR_1:}".equals("someVal")?"boo" + "someVal":"${ENV_VAR_1:}"}'

这篇关于如何在 Spring Boot 的 YML 文件中创建条件属性?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！