tzif_loader

This package is a utility to load IANA Time Zone database files from the local filesystem into TzDatabase records that can be used by the tzif time zone package.

Add to your project with the command:

gleam add tzif_loader@1

Installing the zoneinfo data files

Time zone information is frequently updated, therefore it makes sense to use the package manager for your operating system to keep the time zone database up to date. All common unix variants have time zone database packages and install the time zone database files into the /usr/share/zoneinfo directory by default.

If, however, your system does not have time zone data installed, you can use the zones package to install a database of timezone data as a gleam library and dependency. To use the zones timezone data get the database using the zones.database function rather than loader.load_from_os or loader.load_from_path.

MacOS

The files should be included in your operating system by default. Check the /usr/share/zoneinfo directory and see if they are present.

Ubuntu/Debian Linux Systems

The APT package manager can be used to install the compiled TZif files with the following command:

sudo apt install tzdata

Debian based docker containers

Installing and configuring the time zone database on a Debian or Ubuntu based docker container can be done by adding the following to your Dockerfile:

# Use an ARG for the timezone, with a default of UTC
ARG TIMEZONE=Etc/UTC

# Set the TZ environment variable and install tzdata
RUN apt-get update && \
    export DEBIAN_FRONTEND=noninteractive && \
    ln -fs /usr/share/zoneinfo/${TIMEZONE} /etc/localtime && \
    apt-get install -y tzdata && \
    dpkg-reconfigure --frontend noninteractive tzdata

Alpine Linux Systems

The Alpine Package Keeper can install the time zone database using the command:

sudo apk add tzdata

Alpine based docker containers

Installing and configuring the time zone database on an Alpine based docker container can be done by adding the following to your Dockerfile:

# Use an ARG for the timezone, with a default of UTC
ARG TIMEZONE=Etc/UTC

# 1. Install the tzdata package
# 2. Copy the correct timezone file to /etc/localtime
# 3. Set the TZ environment variable to be used by applications
RUN apk add --no-cache tzdata && \
    cp /usr/share/zoneinfo/${TIMEZONE} /etc/localtime && \
    echo "${TIMEZONE}" > /etc/timezone

Red Hat/Rocky/Alma Linux Systems

You can use the YUM package manager or DNF to install the time zone database on Red Hat variants. To use YUM run the command:

sudo yum install tzdata

Similarly, using DNF:

sudo dnf install tzdata

Further documentation can be found at https://tzif-loader.hexdocs.pm/.