One Liner to download the latest release from your GitHub repo

One Liner to download the latest release from your GitHub repo.md

LOCATION=$(curl -s https://api.github.com/repos/<YOUR ORGANIZTION>/<YOUR REPO>/releases/latest \
| grep "zipball_url" \
| awk '{ print $2 }' \
| sed 's/,$//'       \
| sed 's/"//g' )     \
; curl -L -o <OUTPUT FILE NAME> $LOCATION

for example:

LOCATION=$(curl -s https://api.github.com/repos/csv2db/csv2db/releases/latest \
| grep "zipball_url" \
| awk '{ print $2 }' \
| sed 's/,$//'       \
| sed 's/"//g' )     \
; curl -L -o csv2db.zip $LOCATION

Here is how it goes:

LOCATION=$(...)

stores the output of all the commands in the brackets in the variable $LOCATION

curl -s https://api.github.com/repos/csv2db/csv2db/releases/latest

gets the latest release from your repository, in my case github.com/csv2db/csv2db

grep "zipball_url"

grabs the line for the zipball URL of the file --> "zipball_url": "https://api.github.com/repos/csv2db/csv2db/zipball/v1.5.1",
Note, there is also a tarball_url if you prefer the .tar.gz file instead.

awk '{ print $2 }'

prints just the URL part of the zipball_url line --> "https://api.github.com/repos/csv2db/csv2db/zipball/v1.5.1",

sed 's/,$//'

removes the comma , at the end of the line --> "https://api.github.com/repos/csv2db/csv2db/zipball/v1.5.1"

sed 's/"//g'

removes the double quotes " from the previous output --> https://api.github.com/repos/csv2db/csv2db/zipball/v1.5.1

Once all these commands are executed, the string is stored in the $LOCATION variable due to the surrounding $(...). The next step is to download the file from that location (or, at this stage you can do anything else you like with $LOCATION).

curl -L -o csv2db.zip $LOCATION

invokes cURL and downloads $LOCATION into a file called csv2db.zip. The -L parameter is important so that cURL follows the URL, i.e. redirects on the web page, in case that the URL gets forwarded to https or another location on the server. cURL also has an option to just store the file name under the remove file name. This can be done via -O (uppercase O) rather than -o. If you are using -O you are also advised to use -J which tells the -O option to use the server-specified Content-Disposition filename instead of extracting a filename from the URL.

Nice

if you didn't want to install jq then this also works

curl -s https://api.github.com/repos/swagger-api/swagger-ui/releases/latest |
sed -Ene '/^[[:blank:]]+"tarball_url":[[:blank:]]"(https:[^"]+)",/s//\1/p'

This is great. Thanks! I am testing incorporation of a customized version of this in the MusicPlayerPlus project. That project has release assets for a variety of operating system platforms and architectures. I extended this gist to detect which platform/architecture is the target environment and then, if a release asset is found for that target, automatically install it. This is currently in test. Do you see any problems or have suggestions for how I have extended this gist? This came along right when I needed it. Good timing!

#!/bin/bash

OWNER=<repository_owner>
PROJECT=<repository_name>
API_URL="https://api.github.com/repos/${OWNER}/${PROJECT}/releases/latest"

arch=
centos=
debian=
fedora=
mach=`uname -m`

. /etc/os-release
[ "${ID_LIKE}" == "debian" ] && debian=1
[ "${ID}" == "arch" ] && arch=1
[ "${ID}" == "centos" ] && centos=1
[ "${ID}" == "fedora" ] && fedora=1

DL_URL=
if [ "${arch}" ]
then
  DL_URL=$(curl --silent "${API_URL}" | \
           jq --raw-output '.assets | .[].browser_download_url' | \
           grep "\.pkg\.tar\.zst")
else
  if [ "${centos}" ]
  then
    DL_URL=$(curl --silent "${API_URL}" | \
             jq --raw-output '.assets | .[].browser_download_url' | \
             grep "\.el.*x86_64\.rpm")
  else
    if [ "${fedora}" ]
    then
      DL_URL=$(curl --silent "${API_URL}" | \
               jq --raw-output '.assets | .[].browser_download_url' | \
               grep "\.fc.*x86_64\.rpm")
    else
      if [ "${debian}" ]
      then
        if [ "${mach}" == "x86_64" ]
        then
          DL_URL=$(curl --silent "${API_URL}" | \
                   jq --raw-output '.assets | .[].browser_download_url' | \
                   grep "\.amd64\.deb")
        else
          DL_URL=$(curl --silent "${API_URL}" | \
                   jq --raw-output '.assets | .[].browser_download_url' | \
                   grep "\.arm.*\.deb")
        fi
      else
        printf "\n\tNo release asset found for this platform ..."
      fi
    fi
  fi
fi

[ "${DL_URL}" ] && {
  if [ "${debian}" ]
  then
    TEMP_DEB="$(mktemp)"
    wget --quiet -O "${TEMP_DEB}" "${DL_URL}"
    sudo dpkg -i "${TEMP_DEB}"
    rm -f "${TEMP_DEB}"
  else
    if [ "${centos}" ] || [ "${fedora}" ]
    then
      sudo rpm --quiet --install ${DL_URL}
    else
      [ "${arch}" ] && sudo pacman -U ${DL_URL}
    fi
  fi
}

This looks pretty cool, @doctorfree!

The only thing I'd suggest is making sure that /etc/os-release is executable for the user and if not, throw an error accordingly.
Looking at my machine, the binary is only accessible to root, but not sure whether that's the default or just my env:

[gvenzl@localhost ~]$ ls -al /etc/os-release
lrwxrwxrwx. 1 root root 21 Nov  9  2021 /etc/os-release -> ../usr/lib/os-release
[gvenzl@localhost ~]$ ls -alh /usr/lib/os-release
-rw-r--r-- 1 root root 333 Nov  9  2021 /usr/lib/os-release

/etc/os-release only needs to be readable, not executable, by the user. I believe all Linux distributions set permissions on this as 644 making it readable by all. But, to be sure, a test that /etc/os-release exists and is readable by the user could be performed along with an error if the test fails. Thanks!

Hi @doctorfree,

You are right, somehow I expected it to be a binary because there is a man page for it.
Looking at it, it indeed is only a text file with some variables.

Yeah, nice error messages is always a bonus for the end user :)

for multiple assets, might try:

curl --remote-name-all --location  $( \
    curl -s https://api.github.com/repos/jedisct1/minisign/releases/latest \
    | grep "browser_download_url.*\linux.*" \
    | cut -d : -f 2,3 \
    | tr -d \" )

Awesome, thanks @Binly42!

fwiw, curl -s https://api.github.com/repos/someones/something/releases/latest |jq -r '..| .browser_download_url? // empty'

Cool, thanks @crpb!

If there are updates to older versions more recent than a newer version, you may get the much older version - like when an older version that gets a retrofitted security patch that a newer version just found.

Here's an ugly-but-effective one-liner to sort through the versions by semver (replace cert-manager/cert-manager with your project/repo and zipball_url with the appropriate package type):

# curl the releases JSON, use jq to find every zipball_url, exclude alpha and beta products, get just the trailing part of the URL as version number, sort it ASCIIbetically in reverse order (which should be semver-compliant), pop off the top version number as the latest
FOUND_LATEST_VERSION=$(curl -s https://api.github.com/repos/cert-manager/cert-manager/releases | jq --raw-output .[].zipball_url  | grep -ve alpha -ve beta | awk -F"/" '{print $8}' | sort -r | head -1)

# If $FOUND_LATEST_VERSION doesn't exist, fall back to version v1.0.0
VERSION=${FOUND_LATEST_VERSION:-"v1.0.0"}

echo Downloading version: ${VERSION} from "https://github.com/cert-manager/cert-manager/releases/download/${VERSION}/cert-manager.crds.yaml"
# Use -L with curl to follow redirects
curl -O -L https://github.com/cert-manager/cert-manager/releases/download/${VERSION}/cert-manager.crds.yaml

Nice, thanks @calvinvette!