Quickstart¶

Author:

Rohit Goswami

What you will build¶

By the end of this tutorial you will have:

Wrapped a build command with bless
Read the compressed log output
Filtered the log output

The final output looks like this:

$ bless --label myproject -- make -j8
[2024-01-15T10:30:00Z INFO] gcc -c main.c -o main.o
[2024-01-15T10:30:01Z WARN] main.c:42: warning: unused variable 'x'
[2024-01-15T10:30:02Z INFO] gcc -o myproject main.o

Install bless¶

From source:

git clone https://github.com/HaoZeke/bless
cd bless
cargo install --path .

Verify:

bless --version

Run a command¶

bless --label myproject -- make -j8

This creates myproject_{uuid}.log.gz in the current directory.

Read the log¶

zcat myproject_*.log.gz | head -20

Each line has a timestamp, level, and the original output.

Filter the log¶

Extract warnings and errors with standard tools:

zcat myproject_*.log.gz | grep -E '\b(WARN|ERROR)\b'

Output options¶

Skip the file entirely (stdout only):

bless -o - -- make

Write to a specific path:

bless -o /tmp/build.log.gz -- make

JSON lines output (for piping to jq):

bless --format=jsonl -- make | jq 'select(.level=="WARN")'

Clean output without timestamps:

bless --no-timestamp -- make