remove dependency of urlencoding crate

opentelemetry/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## vNext
 
+### Removed
+- Remove `urlencoding` crate dependency. [#1613](https://github.com/open-telemetry/opentelemetry-rust/pull/1613)
+
 ## v0.22.0
 
 ### Added

opentelemetry/Cargo.toml

@@ -26,7 +26,6 @@ futures-sink = "0.3"
 once_cell = { workspace = true }
 pin-project-lite = { workspace = true, optional = true }
 thiserror = { workspace = true }
-urlencoding = "2.1.2"
 
 [target.'cfg(all(target_arch = "wasm32", not(target_os = "wasi")))'.dependencies]
 js-sys = "0.3.63"

opentelemetry/src/baggage.rs

@@ -19,7 +19,6 @@ use once_cell::sync::Lazy;
 use std::collections::{hash_map, HashMap};
 use std::fmt;
 use std::iter::FromIterator;
-use urlencoding::encode;
 
 static DEFAULT_BAGGAGE: Lazy<Baggage> = Lazy::new(Baggage::default);
 
@@ -282,10 +281,30 @@ impl FromIterator<KeyValueMetadata> for Baggage {
     }
 }
 
+fn encode(s: &str) -> String {
+    let special_characters = ['.', '-', '_', '~'];
+    let mut encoded_string = String::with_capacity(s.len());
+
+    for char in s.chars() {
+        if char.is_ascii_alphanumeric() || special_characters.contains(&char) {
+            encoded_string.push(char);
+        } else if char == ' ' {
+            encoded_string.push_str("%20");
+        } else {
+            let mut buffer = [0; 4];
+            let encoded_char = char.encode_utf8(&mut buffer);
+            for byte in encoded_char.as_bytes() {
+                encoded_string.push_str(&format!("%{:02X}", byte));
+            }
+        }
+    }
+    encoded_string
+}
+
 impl fmt::Display for Baggage {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         for (i, (k, v)) in self.into_iter().enumerate() {
-            write!(f, "{}={}", k, encode(&v.0.as_str()))?;
+            write!(f, "{}={}", k, encode(v.0.as_str().as_ref()))?;
             if !v.1.as_str().is_empty() {
                 write!(f, ";{}", v.1)?;
             }
@@ -473,6 +492,26 @@ mod tests {
         assert_eq!(baggage.len(), 0, "did not insert invalid key");
     }
 
+    #[test]
+    fn test_ascii_values() {
+        let string1 = "test_ 123";
+        let string2 = "Hello123";
+        let string3 = "This & That = More";
+        let string4 = "Unicode: 😊";
+        let string5 = "Non-ASCII: áéíóú";
+        let string6 = "Unsafe: ~!@#$%^&*()_+{}[];:'\\\"<>?,./";
+
+        assert_eq!(encode(string1), "test_%20123");
+        assert_eq!(encode(string2), "Hello123");
+        assert_eq!(encode(string3), "This%20%26%20That%20%3D%20More");
+        assert_eq!(encode(string4), "Unicode%3A%20%F0%9F%98%8A");
+        assert_eq!(
+            encode(string5),
+            "Non-ASCII%3A%20%C3%A1%C3%A9%C3%AD%C3%B3%C3%BA"
+        );
+        assert_eq!(encode(string6), "Unsafe%3A%20~%21%40%23%24%25%5E%26%2A%28%29_%2B%7B%7D%5B%5D%3B%3A%27%5C%22%3C%3E%3F%2C.%2F");
+    }
+
     #[test]
     fn insert_too_much_baggage() {
         // too many key pairs