mholt/PapaParse

meta.cursor value is incorrect if you use parser.pause() and parser.resume()

Open

#321 opened on Jul 7, 2016

View on GitHub
 (10 comments) (4 reactions) (0 assignees)JavaScript (1,157 forks)batch import
help wanted

Repository metrics

Stars
 (11,877 stars)
PR merge metrics
 (Avg merge 18h) (1 merged PR in 30d)

Description

I'm trying to make use of meta.cursor to display a progress bar. The following example works fine:

Papa.parse(file, {
    step: function(results, parser){
         // This gives expected result for cursor
         console.info(result.meta.cursor);
     }
}

Unfortunately, if I make use of parser.pause() and parser.resume() the value for meta.cursor is incorrect. Instead of getting an incrementing value I end up getting a seemingly random number that stays fairly constant and does not add up to the total file size if I sum it up.

Papa.parse(file, {
     step: function(results, parser){
             // This does not give the correct value for cursor
             console.info(result.meta.cursor);
             parser.pause();
             parser.resume();
      }
}

I need to pause the stream because I send the data in chunks to the server for processing and wait for the server to finish before sending the next chunk of data.

Thank you!

Contributor guide

Research direction
Investigate how meta.cursor is updated when parser.pause() and parser.resume() are called. Trace the cursor calculation in the streaming parsing path.
Tech stack
javascript
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaScript
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65