如何为curl任务及60GB大文件处理流程实现进度条？

Alright, let's break this down step by step—adding that slick progress bar you love to both your curl commands and that beast of a 60GB file processing job. Here's how to make it work:

Curl actually comes with built-in progress bar support that you can tweak to match your "Great Example" vibe. No extra tools needed for basic cases:

• For a simple, clean progress bar (similar to many standard examples), use the -# flag:

  curl -# -O https://example.com/large-download.iso
  

• If you want more verbose stats (like download speed, time elapsed, and estimated time remaining), use --progress-bar alongside redirect-following flags:

  curl --progress-bar -L -O https://example.com/large-download.iso
  

The -O flag saves the file with its original name, and -L follows redirects—adjust those based on your specific curl needs.

This is trickier since your pipeline (awk → sort → uniq → wc -l) doesn't have built-in progress tracking. We'll use Pipe Viewer (pv) or the progress utility to add visibility to this 3-hour job.

Option 1: Track File Read Progress with pv #

This gives you a real-time bar showing how much of the 60GB file has been processed by awk—a solid starting point, since most of the time is spent on sorting, but this still keeps you informed:

# First, get the exact size of your file in bytes
FILE_SIZE=$(stat -c%s "$FILE_NAME")

# Run your pipeline with pv tracking input from the file
count=$(pv -s "$FILE_SIZE" "$FILE_NAME" | awk '{print $1}' | sort -T /diskXX --parallel=$PARALLEL | uniq | wc -l)

• pv -s "$FILE_SIZE" tells pv the total file size, so it can calculate accurate progress percentage, speed, and ETA.
• Add flags like -ptbe to pv for extra details: percentage, time elapsed, bytes transferred, and estimated time remaining.

Option 2: Monitor the Sort Process with progress #

Since sorting is the most time-consuming step, you can track the sort process directly using the progress tool (install it via your package manager first, e.g., sudo apt install progress on Debian/Ubuntu):

# Run your processing pipeline in the background, saving output to a temp file
awk '{print $1}' "$FILE_NAME" | sort -T /diskXX --parallel=$PARALLEL | uniq > temp_unique_lines.txt &

# Grab the PID of the background pipeline
PIPELINE_PID=$!

# Use progress to show a live progress bar for the running job
progress -mp "$PIPELINE_PID"

# Once the job finishes, count the lines and clean up the temp file
count=$(wc -l < temp_unique_lines.txt)
rm temp_unique_lines.txt

This will show you real-time IO stats for the sort process, giving you a better sense of how far along the most intensive part of the job is.

Bonus: Integrate Your "Great Example" Progress Bar #

If your "Great Example" is a custom shell script that draws a progress bar, you can parse the output from pv (sent to stderr) to feed percentage updates into it. For example:

FILE_SIZE=$(stat -c%s "$FILE_NAME")
# Run the main processing pipeline in the background
awk '{print $1}' "$FILE_NAME" | sort -T /diskXX --parallel=$PARALLEL | uniq | wc -l &

# Capture pv's stderr output to parse progress percentage
while read -r line; do
  # Extract percentage from pv's output (adjust regex based on pv's format)
  PERCENT=$(echo "$line" | grep -oP '\d+%' | tr -d '%')
  # Call your custom progress bar script with the percentage
  ./your-great-example-progress-bar.sh "$PERCENT"
done < <(pv -s "$FILE_SIZE" "$FILE_NAME" 2>&1 1>/dev/null)

This way, you can use your existing progress bar design instead of relying on pv's default style.

内容的提问来源于stack exchange，提问作者G.Guy