handle encode/decode errors

__test__/index.spec.mjs

@@ -43,3 +43,23 @@ for (const params of [
 ]) {
     test(testEncode, ...params);
 }
+
+test('encode too small', (t) => {
+    let buffer = fs.readFileSync('images/invalid_small.png');
+    let encoded = encodeImage(buffer);
+    let mchash = Buffer.from(encoded.minecraftHash).toString('hex');
+    let error = encoded.error;
+    console.log(error);
+    t.is(mchash, '');
+    t.true(error.includes('too small'));
+})
+
+test('encode too big', (t) => {
+    let buffer = fs.readFileSync('images/invalid_big.png');
+    let encoded = encodeImage(buffer);
+    let mchash = Buffer.from(encoded.minecraftHash).toString('hex');
+    let error = encoded.error;
+    console.log(error);
+    t.is(mchash, '');
+    t.true(error.includes('too small')); // not sure why it says too small
+})

index.d.ts

@@ -9,4 +9,5 @@ export declare class ImageWithHashes {
   png: Buffer
   minecraftHash: Buffer
   hash: Buffer
+  error?: string
 }

src/lib.rs

@@ -15,14 +15,15 @@ const SKIN_DATA_LENGTH: usize = (SKIN_WIDTH * SKIN_HEIGHT * SKIN_CHANNELS);
 
 #[napi]
 pub fn sum(a: i32, b: i32) -> i32 {
-  a + b
+    a + b
 }
 
 #[napi]
 pub struct ImageWithHashes {
     pub png: Buffer,
     pub minecraft_hash: Buffer,
     pub hash: Buffer,
+    pub error: Option<String>,
 }
 
 #[napi]
@@ -37,6 +38,15 @@ pub fn encode_custom_image(buffer: &[u8], width: usize, height: usize) -> ImageW
     decoder.info_png_mut().interlace_method = 0; // should be 0 but just to be sure
 
     let decoded = decoder.decode(buffer);
+    if decoded.is_err() {
+        let error = decoded.unwrap_err();
+        return ImageWithHashes {
+            png: Buffer::from(vec![]),
+            minecraft_hash: Buffer::from(vec![]),
+            hash: Buffer::from(vec![]),
+            error: Some(format!("{:?}", error)),
+        };
+    }
     let decoded1 = decoded.unwrap();
     let decoded_data = decoded1.bytes();
 
@@ -58,6 +68,15 @@ pub fn encode_custom_image(buffer: &[u8], width: usize, height: usize) -> ImageW
 
     let result = encoder.encode(&raw_data, width, height);
     // println!("Result: {:?}", result);
+    if result.is_err() {
+        let error = result.unwrap_err();
+        return ImageWithHashes {
+            png: Buffer::from(vec![]),
+            minecraft_hash: Buffer::from(vec![]),
+            hash: Buffer::from(vec![]),
+            error: Some(format!("{:?}", error)),
+        };
+    }
     let png = result.unwrap();
 
     let mut hasher = Sha256::new();
@@ -72,6 +91,7 @@ pub fn encode_custom_image(buffer: &[u8], width: usize, height: usize) -> ImageW
     ImageWithHashes {
         png: Buffer::from(png.as_slice()),
         minecraft_hash: Buffer::from(minecraft_hash.as_slice()),
-        hash: Buffer::from(hash.as_slice())
+        hash: Buffer::from(hash.as_slice()),
+        error: None,
     }
 }

tools/randomImage.js

@@ -33,6 +33,6 @@ function makeRandomImage(width = 64, height = 64) {
 }
 
 (() => {
-    const { imageBuffer, imageData, data, blob } = makeRandomImage(64, 64);
+    const { imageBuffer, imageData, data, blob } = makeRandomImage(128, 128);
     fs.writeFileSync(`images/randomImage${Math.round(Math.random()*100)}.png`, imageBuffer);
 })();