mirror of
https://github.com/meilisearch/MeiliSearch
synced 2024-11-24 22:04:27 +01:00
115 lines
3.7 KiB
Rust
115 lines
3.7 KiB
Rust
use serde_json::Value;
|
|
|
|
/// Your json MUST BE valid and generated by `serde_json::to_vec` before being
|
|
/// sent in this function. This function is DUMB and FAST but makes a lot of
|
|
/// asumption about the way `serde_json` will generate its input.
|
|
///
|
|
/// Will return `true` if the JSON contains an object, an array of array
|
|
/// or an array containing an object. Returns `false` for everything else.
|
|
pub fn should_flatten_from_unchecked_slice(json: &[u8]) -> bool {
|
|
if json.is_empty() {
|
|
return false;
|
|
}
|
|
|
|
// since the json we receive has been generated by serde_json we know
|
|
// it doesn't contains any whitespace at the beginning thus we can check
|
|
// directly if we're looking at an object.
|
|
if json[0] == b'{' {
|
|
return true;
|
|
} else if json[0] != b'[' {
|
|
// if the json isn't an object or an array it means it's a simple value.
|
|
return false;
|
|
}
|
|
|
|
// The array case is a little bit more complex. We are looking for a second
|
|
// `[` but we need to ensure that it doesn't appear inside of a string. Thus
|
|
// we need to keep track of if we're in a string or not.
|
|
|
|
// will be used when we met a `\` to skip the next character.
|
|
let mut skip_next = false;
|
|
let mut in_string = false;
|
|
|
|
for byte in json.iter().skip(1) {
|
|
match byte {
|
|
// handle the backlash.
|
|
_ if skip_next => skip_next = false,
|
|
b'\\' => skip_next = true,
|
|
|
|
// handle the strings.
|
|
byte if in_string => {
|
|
if *byte == b'"' {
|
|
in_string = false;
|
|
}
|
|
}
|
|
b'"' => in_string = true,
|
|
|
|
// handle the arrays.
|
|
b'[' => return true,
|
|
// since we know the json is valid we don't need to ensure the
|
|
// array is correctly closed
|
|
|
|
// handle the objects.
|
|
b'{' => return true,
|
|
|
|
// ignore everything else
|
|
_ => (),
|
|
}
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// Consider using [`should_flatten_from_unchecked_slice`] when you can.
|
|
/// Will returns `true` if the json contains an object, an array of array
|
|
/// or an array containing an object.
|
|
/// Returns `false` for everything else.
|
|
/// This function has been written to test the [`should_flatten_from_unchecked_slice`].
|
|
pub fn should_flatten_from_value(json: &Value) -> bool {
|
|
match json {
|
|
Value::Object(..) => true,
|
|
Value::Array(array) => array.iter().any(|value| value.is_array() || value.is_object()),
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use serde_json::*;
|
|
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_shouldnt_flatten() {
|
|
let shouldnt_flatten = vec![
|
|
json!(null),
|
|
json!(true),
|
|
json!(false),
|
|
json!("a superb string"),
|
|
json!("a string escaping other \"string\""),
|
|
json!([null, true, false]),
|
|
json!(["hello", "world", "!"]),
|
|
json!(["a \"string\" escaping 'an other'", "\"[\"", "\"{\""]),
|
|
];
|
|
for value in shouldnt_flatten {
|
|
assert!(!should_flatten_from_value(&value));
|
|
let value = serde_json::to_vec(&value).unwrap();
|
|
assert!(!should_flatten_from_unchecked_slice(&value));
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_should_flatten() {
|
|
let should_flatten = vec![
|
|
json!({}),
|
|
json!({ "hello": "world" }),
|
|
json!(["hello", ["world"]]),
|
|
json!([true, true, true, true, true, true, true, true, true, {}]),
|
|
];
|
|
for value in should_flatten {
|
|
assert!(should_flatten_from_value(&value));
|
|
let value = serde_json::to_vec(&value).unwrap();
|
|
assert!(should_flatten_from_unchecked_slice(&value));
|
|
}
|
|
}
|
|
}
|