40 lines
1.1 KiB
Rust
40 lines
1.1 KiB
Rust
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use std::error::Error;
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use base64::Engine;
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use serde::{Serialize, Deserialize};
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#[derive(Serialize, Deserialize, Debug, Clone)]
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pub struct Cursor {
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pub page: u64
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}
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impl TryFrom<Cursor> for String {
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type Error = Box<dyn Error>;
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fn try_from(value: Cursor) -> Result<Self, Self::Error> {
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// Serialize it to json
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let json_str = serde_json::to_string(&value)?;
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// Then base64-encode the json
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let base64_str = base64::engine::general_purpose::STANDARD.encode(json_str);
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Ok(base64_str)
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}
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}
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impl TryFrom<String> for Cursor {
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type Error = Box<dyn Error>;
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fn try_from(value: String) -> Result<Self, Self::Error> {
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if value.is_empty() {
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// If empty, it's page 0
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return Ok(Cursor {
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page: 0
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})
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}
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// Base64-decode the value
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let json_bytes = base64::engine::general_purpose::STANDARD.decode(value)?;
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// Convert it into a string
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let json_str = String::from_utf8(json_bytes)?;
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// Deserialize it from json
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let cursor = serde_json::from_str(&json_str)?;
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Ok(cursor)
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}
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}
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