Download and Uploading Latest Release Assets

github_release_asset_api.sh

#!/usr/bin/env bash

# First, store your PERSONAL GITHUB TOKEN as secret file somewhere. 
# You can generate your personal github token here: https://github.com/settings/tokens. Check the 
# "Full control of private repositories" scope.
# In the example below, token is stored as a json file "github_token.json" under secrets directory in the form of:
# { "token": "PERSONAL_GITHUB_TOKEN" }

# Check Secrets
[[ -f secrets/github_token.json ]] || { echo "Error: github token is unavailable!" >&2;  exit 1; }
GITHUB_API_TOKEN=`cat secrets/github_token.json | jq -r '.token'`
AUTH="Authorization: token $GITHUB_API_TOKEN"

# Read user inputs
read -p "Enter your github repo (eg: USER/REPO_NAME or ORG/REPO_NAME): " GITHUB_REPO && [[ -n $GITHUB_REPO ]] || {
    echo "GITHUB_REPO must be set!" >&2; exit 1; 
}
read -p "Enter asset filename: " ASSET_FILE && [[ -n $ASSET_FILE ]] || {
    echo "ASSET_FILE must be set!" >&2; exit 1; 
}
read -p "Upload/Download? (u/d): " operation && [[ $operation == [uUdD] ]] || { 
    echo "Operation must be either u (upload) or d (download)!" >&2; exit 1; 
}

# Github related APIs
GITHUB_API="https://api.github.com"
GITHUB_REPO_API="$GITHUB_API/repos/$GITHUB_REPO"
GITHUB_LATEST_RELEASE_API="$GITHUB_REPO_API/releases/latest"

get_latest_release(){
    response=`curl -sH "$AUTH" "$GITHUB_LATEST_RELEASE_API"`
    echo "$response"
}

get_asset_url(){
    asset_url=$(echo $1 | jq -r --arg name "$ASSET_FILE" '.assets[] | select(.name == $name).url')
    echo "$asset_url"
}

get_upload_url(){
    upload_url=$(echo $1 | jq -r '.upload_url')
    echo "$upload_url"
}

upload_asset(){
    response=`get_latest_release`
    
    # Construct asset url
    asset_url=`get_asset_url "$response"`
    echo "Asset URL: $asset_url"
    
    # Construct upload url
    upload_url=`get_upload_url "$response"`
    GITHUB_UPLOAD_ASSET_API=`echo $upload_url | sed "s/{?name,label}/?name=${ASSET_FILE}/g"`
    echo "Upload URL: $GITHUB_UPLOAD_ASSET_API"

    # Delete resource first if exist
    [[ -n "$asset_url" ]] && {
        echo "Deleting old resource"
        curl -X DELETE -L# -H "$AUTH" $asset_url
    }

    echo "Uploading new resource"
    curl --request PATCH -L# --data-binary @"$ASSET_FILE" -H "$AUTH" -H "Content-Type: application/octet-stream" $GITHUB_UPLOAD_ASSET_API
}

download_asset(){
    response=`curl -sH "$AUTH" "$GITHUB_REPO_API/releases/latest"`
    asset_url=$(echo "$response" | jq -r --arg name "$ASSET_FILE" '.assets[] | select(.name == $name).url')

    echo "Downloading $ASSET_FILE... from $asset_url"
    curl -L# -H 'Accept: application/octet-stream' "$asset_url?access_token=$GITHUB_API_TOKEN" -o ${ASSET_FILE}
    echo "Downloading $ASSET_FILE done!"

    echo "Extracting ${ASSET_FILE}..."
    if [[ -f ${ASSET_FILE} ]]; then
        tar -xvzf ${ASSET_FILE};
    else
        echo "Error: failure to download $ASSET_FILE!" >&2;
        exit 1;
    fi
}

# Check auth
curl -o /dev/null -sH "$AUTH" "$GITHUB_REPO_API" || { echo "Error: Invalid repo, token or network issue!" >&2;  exit 1; }

if [[ $operation == [dD] ]]; then download_asset; else upload_asset; fi