4732603a42
Gotta know how to `to_string` things Change-Id: I259ef61ecaf6ae7fabe0b3d211706ba5f429b3a7 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6057 Reviewed-by: wpcarro <wpcarro@gmail.com> Autosubmit: wpcarro <wpcarro@gmail.com> Tested-by: BuildkiteCI
81 lines
2.6 KiB
Rust
81 lines
2.6 KiB
Rust
use serde::{Deserialize, Serialize};
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use serde_json::{json, Value};
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// From the serde_json docs:
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//
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// > There are three common ways that you might find yourself needing to work
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// > with JSON data in Rust.
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// >
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// > 1. As text data. An unprocessed string of JSON data that you receive on an
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// > HTTP endpoint, read from a file, or prepare to send to a remote server.
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// > 2. As an untyped or loosely typed representation. Maybe you want to check
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// > that some JSON data is valid before passing it on, but without knowing
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// > the structure of what it contains. Or you want to do very basic
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// > manipulations like insert a key in a particular spot.
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// > 3. As a strongly typed Rust data structure. When you expect all or most of
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// > your data to conform to a particular structure and want to get real work
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// > done without JSON’s loosey-goosey nature tripping you up.
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//
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// So let's take a look at all three...
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////////////////////////////////////////////////////////////////////////////////
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// Types
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////////////////////////////////////////////////////////////////////////////////
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#[derive(Serialize, Deserialize, Debug)]
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struct Person {
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fname: String,
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lname: String,
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age: u8,
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}
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////////////////////////////////////////////////////////////////////////////////
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// Functions
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////////////////////////////////////////////////////////////////////////////////
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// 1) Reading/writing from/to plain text.
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// TL;DR:
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// - read: serde_json::from_str(data)
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// - write: x.to_string()
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pub fn one() {
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let data = json!({
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"fname": "William",
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"lname": "Carroll",
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"age": 30,
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})
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.to_string();
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println!("result: {:?}", data);
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}
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// 2) Parse into a loosely typed representation; mutate it; serialize it back.
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// TL;DR:
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// - read: serde_json::from_str(data)
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// - write: x.to_string()
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pub fn two() {
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let data = r#"{"fname":"William","lname":"Carroll","age":30}"#;
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let mut parsed: Value = serde_json::from_str(data).unwrap();
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parsed["fname"] = json!("Norm");
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parsed["lname"] = json!("Macdonald");
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parsed["age"] = json!(61);
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let result = parsed.to_string();
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println!("result: {:?}", result);
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}
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// 3) Parse into a strongly typed structure.
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// TL;DR:
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// - read: serde_json::from_str(data)
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// - write: serde_json::to_string(x).unwrap()
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pub fn three() {
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let data = r#"{"fname":"William","lname":"Carroll","age":30}"#;
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let mut read: Person = serde_json::from_str(data).unwrap();
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read.fname = "Norm".to_string();
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read.lname = "Macdonald".to_string();
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read.age = 61;
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let write = serde_json::to_string(&read).unwrap();
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println!("result: {:?}", write);
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}
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