mrsarm

#!/usr/bin/env sh

# Get a file from a GitHub repository, trying first to download it
# from a branch passed by argument, if the file doesn't exist,
# fallback to another branch version.
#
# Script to be called from Github Actions as following:
#
#     - name: Get GitHub downloader
#       run: wget https://gist.github.com/mrsarm/95279381f3d8bf4269499fb437888e2c/raw/github-file.sh

mrsarm

/// Multi-thread example in Rust of iterating a vector as input data in chunks,
/// using threads in a safe way, using the threads and the channels APIs, and
/// the `Arc` type.
///
/// ## Details
///
/// Spawn MAX_NTHREADS number of threads, then from each thread borrow a slice
/// of the vector data, and from each string inside
/// the slice, calculate a new string and publish it into a channel, that
/// can then be listened by a receiver from the main thread, while the

mrsarm

/**
 * Execute concurrently the asynchronous functions `fns` passed, but
 * not more than `maxConcurrency` at the same time. All functions
 * return the same type T, an a promise with T[] inside is returned.
 */
const execConcurrent = async<T> (
  fns: (() => Promise<T>)[],
  maxConcurrency: number,
): Promise<T[]> => {
  const res: T[] = [];

mrsarm

-- Delete Database with connections opened

-- Postgres older than 13 don't support FORCE option, in this case pg_terminate_backend() is used:

SELECT pid, pg_terminate_backend(pid)
  FROM pg_stat_activity
  WHERE pg_stat_activity.datname = 'dbname';

DROP DATABASE dbname;

mrsarm

#!/usr/bin/env bash

if [ "$1" == "-h" -o "$1" == "--help" -o "$#" == "0" ]
then
    echo "Convert what ever video file to a compatible MP4 file"
    echo "that works on most devices."
    echo
    echo "Usage: video2mp4.sh [FILE]"
    exit
fi

mrsarm

Install Python from sources

On Ubuntu or compatible:

sudo apt-get install build-essential libsqlite3-dev sqlite3 bzip2 libbz2-dev zlib1g-dev libssl-dev libffi-dev lzma liblzma-dev

Download Python source and install as normal user with (replace prefix path, e.g. /opt/py/python3.11):

mrsarm

-- DB size in bytes
SELECT pg_size_pretty( pg_database_size('dbname') );

-- Table size in bytes
SELECT pg_size_pretty( pg_total_relation_size('tablename') );


-- All table sizes sorted by size desc
SELECT table_name, pg_size_pretty( pg_relation_size(quote_ident(table_name)) )
  FROM information_schema.tables

mrsarm

#!/usr/bin/env bash

if [ "$1" == "-h" -o "$1" == "--help" ]; then
  echo 'docker-compose-services: list all services found in the docker-compose.yml file'
  exit
fi

cat docker-compose.y*ml | grep -oP '(?<=^  )(\w|-)+(?=:)'

mrsarm

#!/usr/bin/env bash
#
# taillog: tail FILE highlighting with colors the severity.
#
#   Based in the script found at https://serverfault.com/a/1022806/256983
#
#   TODO: check whether the syntax "\<MESSAGE\>" offers better compatibility than "\bMESSAGE\b" to match whole words only (Mac OS)

if [ "$1" = "-h" -o "$1" = "--help" ]
then

mrsarm

# \t\a\o /tmp/out.json
--Tuples only is off.
--Output format is aligned.
SELECT row_to_json(r) FROM my_table AS r;
# \t\a\o
--Tuples only is off.
--Output format is aligned.