我有测试,我需要将 JSON 数据发送到我的服务器。我有以下测试:
extern crate hyper;
extern crate rustc_serialize;
use std::io::Read;
use hyper::*;
#[derive(RustcDecodable, RustcEncodable)]
struct LegacyJsonRequest {
jsonrpc: String,
method: String,
params: String,
id: i32,
auth: String,
}
#[test]
fn apiinfo_jsonrpc_tests() {
let client = Client::new();
let url = "http://localhost:6767/api_jsonrpc.php";
let mut http_reader = header::Headers::new();
http_reader.set_raw("Content-Type", vec![b"application/json".to_vec()]);
//TODO: How to use a struct and 'export' it to a raw string literal???
let request_data = LegacyJsonRequest {
jsonrpc: "2.0".to_string(),
method: "apiinfo.version".to_string(),
params: "[]".to_string(),
auth: "[]".to_string(),
id: 1,
};
let encoded_request = rustc_serialize::json::encode(&request_data).unwrap();
let mut response = client.post(url)
.body(encoded_request)
.send()
.unwrap();
}
使用此代码,将返回以下错误:
error[E0277]: the trait bound `hyper::client::Body<'_>: std::convert::From<std::string::String>` is not satisfied
如果我删除结构和 JSON 编码代码并创建一个简单的原始字符串文字并在 body 方法上引用它,它就可以工作。示例:
extern crate hyper;
extern crate rustc_serialize;
use std::io::Read;
use hyper::*;
#[derive(RustcDecodable, RustcEncodable)]
struct LegacyJsonRequest {
jsonrpc: String,
method: String,
params: String,
id: i32,
auth: String,
}
#[test]
fn apiinfo_jsonrpc_tests() {
let client = Client::new();
let url = "http://localhost:6767/api_jsonrpc.php";
let mut http_reader = header::Headers::new();
http_reader.set_raw("Content-Type", vec![b"application/json".to_vec()]);
let request_data =
r#"{"jsonrpc":"2.0", "method": "apiinfo.version", "params": {}, "auth": {}, "id": "1"}"#;
let mut response = client.post(url)
.body(request_data)
.send()
.unwrap();
}
那么:如何将我的结构或 JSON 转换为原始字符串?
我知道错误 E0277 是关于“Hyper::client::Body<'_>”的特性的实现,但是看,这不是问题;问题是:如何将结构或 JSON 转换为原始字符串,仅此而已。谢谢。
最佳答案
I Know that the error E0277 is about the implementation of a trait for the "Hyper::client::Body<'_>", but look, this is not the question; the question is: how to convert a struct or JSON into a raw string, nothing more.
转换为原始字符串是 100% 不可能。
你看,“原始字符串”一旦源代码被解析就不存在了——它们只是源代码的一个自负。无法将任何内容 转换为原始字符串,因为它不存在可将转换为。
所有存在的都是字符串切片(&str
)和拥有的字符串(String
)。
根据要求,这解决了 OP 的问题,仅此而已。欢迎任何对潜在问题的解决方案感兴趣的人继续阅读。
检查 documentation for RequestBuilder::body
,您可以看到它接受任何可以转换为 Body
的类型:
impl<'a> RequestBuilder<'a> {
fn body<B: Into<Body<'a>>>(self, body: B) -> RequestBuilder<'a>;
}
如果您随后查看 documentation for Body
,您将看到它存在哪些 From
实现:
impl<'a, R: Read> From<&'a mut R> for Body<'a> {
fn from(r: &'a mut R) -> Body<'a>;
}
再加上知识From
implies Into
,您知道您可以将实现 Read
的任何内容传递给 body
。实际上,编译器会在错误消息中告诉您:
error[E0277]: the trait bound `hyper::client::Body<'_>: std::convert::From<std::string::String>` is not satisfied
--> src/main.rs:37:10
|
37 | .body(encoded_request)
| ^^^^ the trait `std::convert::From<std::string::String>` is not implemented for `hyper::client::Body<'_>`
|
= help: the following implementations were found:
= help: <hyper::client::Body<'a> as std::convert::From<&'a mut R>>
= note: required because of the requirements on the impl of `std::convert::Into<hyper::client::Body<'_>>` for `std::string::String`
这就是问题所在 - 实际上有 更多 方法可以转换为 Body
,但文档没有显示它们1! checkout the source ,你可以看到:
impl<'a> Into<Body<'a>> for &'a str {
#[inline]
fn into(self) -> Body<'a> {
self.as_bytes().into()
}
}
impl<'a> Into<Body<'a>> for &'a String {
#[inline]
fn into(self) -> Body<'a> {
self.as_bytes().into()
}
}
这意味着您可以传入对字符串的引用,然后将其转换为Body
,就像vitalyd guessed一样。 :
let mut response = client.post(url)
.body(&encoded_request)
.send()
.unwrap();
1 我要查看这是否已提交问题,因为这看起来确实不正确。
关于string - 如何将结构或 JSON 转换为原始字符串?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/42352499/