Bug Fix: Json Decoder aggessively pulls json (#867)

* wait for newline char b4 decoding json

* remove noisy console log

* linters

---------

Co-authored-by: Nathan Sarrazin <[email protected]>

src/lib/server/endpoints/llamacpp/endpointLlamacpp.ts

@@ -55,10 +55,13 @@ export function endpointLlamacpp(
  let stop = false;
  let generatedText = "";
  let tokenId = 0;
+ let accumulatedData = ""; // Buffer to accumulate data chunks
+
  while (!stop) {
- // read the stream and log the outputs to console
+ // Read the stream and log the outputs to console
  const out = (await reader?.read()) ?? { done: false, value: undefined };
- // we read, if it's done we cancel
+
+ // If it's done, we cancel
  if (out.done) {
  reader?.cancel();
  return;
@@ -68,31 +71,49 @@ export function endpointLlamacpp(
  return;
  }
 
- if (out.value.startsWith("data: ")) {
- let data = null;
- try {
- data = JSON.parse(out.value.slice(6));
- } catch (e) {
- return;
- }
- if (data.content || data.stop) {
- generatedText += data.content;
- const output: TextGenerationStreamOutput = {
- token: {
- id: tokenId++,
- text: data.content ?? "",
- logprob: 0,
- special: false,
- },
- generated_text: data.stop ? generatedText : null,
- details: null,
- };
- if (data.stop) {
- stop = true;
- reader?.cancel();
+ // Accumulate the data chunk
+ accumulatedData += out.value;
+
+ // Process each complete JSON object in the accumulated data
+ while (accumulatedData.includes("\n")) {
+ // Assuming each JSON object ends with a newline
+ const endIndex = accumulatedData.indexOf("\n");
+ let jsonString = accumulatedData.substring(0, endIndex).trim();
+
+ // Remove the processed part from the buffer
+ accumulatedData = accumulatedData.substring(endIndex + 1);
+
+ if (jsonString.startsWith("data: ")) {
+ jsonString = jsonString.slice(6);
+ let data = null;
+
+ try {
+ data = JSON.parse(jsonString);
+ } catch (e) {
+ console.error("Failed to parse JSON", e);
+ console.error("Problematic JSON string:", jsonString);
+ continue; // Skip this iteration and try the next chunk
+ }
+
+ // Handle the parsed data
+ if (data.content || data.stop) {
+ generatedText += data.content;
+ const output: TextGenerationStreamOutput = {
+ token: {
+ id: tokenId++,
+ text: data.content ?? "",
+ logprob: 0,
+ special: false,
+ },
+ generated_text: data.stop ? generatedText : null,
+ details: null,
+ };
+ if (data.stop) {
+ stop = true;
+ reader?.cancel();
+ }
+ yield output;
  }
- yield output;
- // take the data.content value and yield it
  }
  }
  }