英文:
How to dynamically access objects in ftl?
问题
我已经将我的数据模型存储在以下的YAML文件中：
users:
- "u1"
- "u2"
u1:
name: "user1"
age: 25
u2:
name: "user2"
age: 26
我尝试使用以下的模板（FTL）来生成用户记录：
[
<#list users as user>
{
"username": "${${user}.name}",
"userage": "${${user}.age}"
},
</#list>
]
我的最终输出应该如下所示：
[
{
"username": "user1",
"userage": "25"
},
{
"username": "user2",
"userage": "26"
}
]
如何实现这个？我遇到了以下错误：
英文:
I have my data model stored in yaml as below
users:
- "u1"
- "u2"
u1:
name: "user1"
age: 25
u2:
name: "user2"
age: 26
I am trying to use the below template (ftl) to generate user records
[
<#list users as user>
{
"username": "${${user}.name}"
"userage": "${${user}.age}"
},
</#list>
]
my final output should look like:
[
{
"username": "user1",
"userage": "25"
},
{
"username": "user2",
"userage": "26"
}
]
How to achieve this? I am getting below error
答案1
得分: 1
你要查找的表达式是 .vars[user].name（其中 [] 通过动态键进行查找，而 .vars 是一个特殊变量，用于引用所有顶层变量）。然后，你可以将整个内容放入 ${} 中，以便在需要时使用。你还可以使用 <#assign userObj = .vars[user]>，然后稍后只需编写 userObj.name 和 userObj.age。（不过，关于名称选择，我建议使用 userId 代替 user，以及 user 代替 userObj。）
最后，如果可能的话，数据模型应该像这样简单明了：
users:
u1:
name: "user1"
age: 25
u2:
name: "user2"
age: 26
这样你就可以像这样编写 users.u1.age。如果用户ID是动态的，假设它存储在 userId 变量中，那么你可以编写 users[userId].age。
英文:
The expression you are looking for is .vars[user].name (where [] does the lookup by a dynamic key, and .vars is a special variable to refer to all your top-level variables). Then you can put that whole thing into ${} where that's needed. You can also do <#assign userObj = .vars[user]>, and then later just write userObj.name, and userObj.age. (Though, regrading the name choices, I would use userId instead of user, and user instead of userObj.)
Last not least, the data-model should just be like this, if possible, and then everything is simpler, and less confusing:
users:
u1:
name: "user1"
age: 25
u2:
name: "user2"
age: 26
So then you can write something like users.u1.age. If the user ID is dynamic, and let's say it's in the userId variable, then you can write users[userId].age.
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