使用Spring Boot和Thymeleaf创建文件下载链接 [英] Creating a file download link using Spring Boot and Thymeleaf

问题描述

这听起来像是一个琐碎的问题，但是经过数小时的搜索，我还没有找到答案。据我了解，问题是我试图从控制器返回 FileSystemResource ，Thymeleaf希望我提供一个 String 资源，它将使用该资源呈现下一页。但是由于返回的是 FileSystemResource ，因此出现以下错误：

  org.thymeleaf.exceptions.TemplateInputException：解决模板产品/下载时出错，模板可能不存在或任何配置的模板解析器
   
 
 
我使用的控制器映射是：
  @RequestMapping（value =  / products / download，method = RequestMethod.GET）
 public FileSystemResource downloadFile（@Param（value = id）Long id）{
产品product = productRepo.findOne（id）; 
返回新的FileSystemResource（new File（product.getFileUrl（）））; 
} 
  
我的HTML链接如下所示：
 < a th：href = $ {'products / download？id ='+ product.id}>< span th：text = $ {product.name}< / span>< / a> 
  
我不想重定向到任何地方，我只需要在单击链接后下载文件。这实际上是正确的实施方式吗？我不确定。
解决方案
您需要更改 th：href 看起来像这样：
 < a th：href = @ {| / products / download？id = $ { product.id} |}>< span th：text = $ {product.name}>< / span>< / a> 
  
然后，您还需要更改控制器并包含 @ResponseBody 批注：
  @RequestMapping（value = / products / download，method = RequestMethod.GET）
 @ResponseBody 
 public FileSystemResource downloadFile（@Param（value = id）Long id）{
产品product = productRepo.findOne（id）; 
返回新的FileSystemResource（new File（product.getFileUrl（）））; 
} 
  
 
This might sound like a trivial question, but after hours of searching I am yet to find an answer to this. The problem, as far as I understand, is that I am trying to return a FileSystemResource from the controller and Thymeleaf expects me to supply a String resource using which it will render the next page. But since I am returning a FileSystemResource, I get the following error:
org.thymeleaf.exceptions.TemplateInputException: Error resolving template "products/download", template might not exist or might not be accessible by any of the configured Template Resolvers
The controller mapping I have used is:
@RequestMapping(value="/products/download", method=RequestMethod.GET)
public FileSystemResource downloadFile(@Param(value="id") Long id) {
    Product product = productRepo.findOne(id);
    return new FileSystemResource(new File(product.getFileUrl()));
}
My HTML link looks something like this:
<a th:href="${'products/download?id=' + product.id}"><span th:text="${product.name}"></span></a>
I don't want to be redirected anywhere, I just need the file downloaded once the link is clicked. Is this actually the right implementation? I'm not sure.
解决方案
You need to change the th:href to look like:
<a th:href="@{|/products/download?id=${product.id}|}"><span th:text="${product.name}"></span></a>
Then also you need to change your controller and include the @ResponseBody annotation:
@RequestMapping(value="/products/download", method=RequestMethod.GET)
@ResponseBody
public FileSystemResource downloadFile(@Param(value="id") Long id) {
    Product product = productRepo.findOne(id);
    return new FileSystemResource(new File(product.getFileUrl()));
}


                        
这篇关于使用Spring Boot和Thymeleaf创建文件下载链接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！