Migrate and refactor from lu0/git-scripts/git-partial-clone to make i…

…t a submodule.

.gitignore

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+tmp/
+releases/
+

README.md

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+`git-partial-clone`
+---
+
+This script clones a subdirectory of a github/gitlab repository.
+
+# Usage
+## Quick test
+Test the script with the example config file.
+By the end of the execution, you will see a `tmp` directory containing the subfolder of the example repository.
+```zsh
+./git-partial-clone.sh example.conf
+```
+## Install
+Add the script to your `PATH`
+```zsh
+ln -srf git-partial-clone.sh ~/.local/bin/git-partial-clone
+```
+Then you can execute the script from any directory with your custom config file.
+```zsh
+git-partial-clone path/to/your/config/file.conf
+```
+
+# Configuration
+Fill in the config file ([`template.conf`](./template.conf)) with the information of the repository you're cloning. You can see the example file [here](./example.conf).
+
+## Mandatory variables
+
+- `GIT_HOST`:
+    - `github` if the repository is hosted on Github.
+    - `gitlab` if the repository is hosted on Gitlab.
+- `REPO_OWNER`:
+    - Username of the owner/author of the repository.
+- `REPO_NAME`:
+    - Name of the repository to be cloned.
+- **`REMOTE_PARTIAL_DIR`**:
+    - **Subdirectory of the repository you want to clone**.
+    - Omit it to clone the entire repository.
+
+## Mandatory variables for **private repositories**
+You will need to generate an access token in order to clone private repositories, as password authentication is deprecated.
+
+- Github: [github.com/settings/tokens](https://github.com/settings/tokens).
+- Gitlab: [gitlab.com/-/profile/personal_access_tokens](https://gitlab.com/-/profile/personal_access_tokens).
+
+Once you have a token, store it in a file.
+
+- `TOKEN_PATH`:
+    - Path to the file containing the access token.
+- `GIT_USER`:
+    - Username with access to the repository.
+
+## Optional variables
+The following variables give you more control over the objects you're cloning.
+- `BRANCH`:
+    - The branch to be fetched.
+    - Omit it to pull all of the branches and switch to the default one.
+- `COMMIT_DEPTH`:
+    - Number of commits you want to fetch (useful for deployment purposes).
+    - Omit it to fetch the entire remote history.
+- `PARENT_DIR`:
+    - Path to the target parent directory.
+    - Omit it to clone the repository in the current directory.
+

example.conf

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+#
+# Example of the git-partial-clone configuration file
+#
+# Copyright (c) 2021 Lucero Alvarado 
+#   https://github.com/lu0/git-partial-clone
+#
+# THIS FILE DOES NOT SUPPORT INLINE COMMENTS!
+#
+
+GIT_HOST=github
+REPO_OWNER=lu0
+REPO_NAME=vscode-settings
+REMOTE_PARTIAL_DIR=json/snippets
+
+TOKEN_PATH=
+GIT_USER=
+
+BRANCH=
+COMMIT_DEPTH=3
+
+PARENT_DIR=tmp
+

git-partial-clone.sh

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+#!/bin/bash
+
+#
+# The git-partial-clone script
+#   Clone a subdirectory of a github/gitlab repository
+#
+# Copyright (c) 2021 Lucero Alvarado 
+#   https://github.com/lu0/git-partial-clone
+#
+
+CONFIG_FILE_PATH=${1}
+
+git-partial-clone() {
+    # Source config file
+    [ ${1} ] \
+        && get-variables-from-file ${1} \
+        || { notif err "git-partial-clone requires a configuration file." && abort ;}
+
+    check-mandatory-vars "GIT_HOST REPO_NAME REPO_OWNER" || abort
+    get-token-from-file "${TOKEN_PATH}" GIT_TOKEN
+
+    # Change working directory
+    get-clone-dir-path "${PARENT_DIR}" "${REPO_NAME}" CLONE_DIR || abort
+    mkdir "${CLONE_DIR}" && cd "${CLONE_DIR}" || abort
+
+    # Add origin
+    [ -d "${CLONE_DIR}"/.git/ ] \
+        && notif err "${CLONE_DIR} is already a git directory." && abort \
+        || git init
+    GIT_URL=${GIT_HOST}.com/${REPO_OWNER}/${REPO_NAME}
+    [ ${GIT_USER} ] && [ ${GIT_TOKEN} ] \
+        && git remote add origin https://${GIT_USER}:${GIT_TOKEN}@${GIT_URL}.git \
+        || git remote add origin https://${GIT_URL}.git
+
+    enable-partial-clone ${CLONE_DIR} ${REMOTE_PARTIAL_DIR}
+    fetch-commit-history ${CLONE_DIR} ${COMMIT_DEPTH}
+
+    # Pull branch(es)
+    [ ${BRANCH} ] \
+        && { notif ok "Trying to fetch branch ${BRANCH}" && \
+             pull-single-branch ${CLONE_DIR} ${BRANCH} ;} \
+        || { notif warn "BRANCH not specified, pulling every branch in ${REPO_NAME}." && \
+             pull-all-branches ${CLONE_DIR} ;}
+
+    # Done
+    [ ${REMOTE_PARTIAL_DIR} ] \
+        && notif ok "${REMOTE_PARTIAL_DIR} of https://${GIT_URL} was cloned into" \
+        || notif ok "https://${GIT_URL} was cloned into"
+    notif ok "${CLONE_DIR}"
+    cd - && unset-variables-from-file ${1}
+}
+
+check-mandatory-vars() {
+    # Returns an error if a mandatory variable is missing.
+    # Usage: check-mandatory-vars ${STRING_OF_SPACE_SEPARATED_VAR_NAMES}
+    local vars_arr=($1)
+    local count=0
+    for var_name in "${vars_arr[@]}"; do
+        local var_value="${!var_name}"
+        # echo "$var_name=${var_value}"
+        [ "${var_value}" ] \
+            || { notif err "$var_name is mandatory." && ((++count)) ;}
+    done
+    [[ $count -eq 0 ]] && return 0 || return 1
+}
+
+get-token-from-file() {
+    # Reads the contents of the token file
+    # Usage: get-token-from-file <path to token file> <OUTPUT_VARIABLE_NAME>
+    eval TOKEN_PATH="${1}"  # expand quoted path
+    MSG_NO_TOKEN="The repository must be public in order to be cloned."
+    MSG_TOKEN_PROVIDED="A token was found! The repository will be cloned if you have access to it."
+
+    [[ -z $TOKEN_PATH ]] \
+        && notif warn "You did not provide a token. ${MSG_NO_TOKEN}" \
+        || { MY_TOKEN=$(cat ${TOKEN_PATH}) && [ ${MY_TOKEN} ] \
+                && eval "${2}='${MY_TOKEN}'" && notif ok "${MSG_TOKEN_PROVIDED}" \
+                || notif err "Could not find a token in ${TOKEN_PATH}. ${MSG_NO_TOKEN}" ;}
+}
+
+get-clone-dir-path() {
+    # Returns the path where the repository will be cloned.
+    # Usage: get-clone-dir-path <parent path> <name of repository> <OUTPUT_VARIABLE_NAME>
+    local PARENT_DIR="${1}"
+    local REPO_NAME="${2}"
+    [[ -z "${PARENT_DIR}" ]] && PARENT_DIR=${PWD} && notif warn "PARENT_DIR is blank"
+
+    # Convert to absolute
+    [[ "${PARENT_DIR:0:1}" != "/" ]] && PARENT_DIR=${PWD}/${PARENT_DIR}
+
+    # Remove leading slash
+    [[ "${PARENT_DIR}" == */ ]] && PARENT_DIR="${PARENT_DIR: : -1}"
+
+    mkdir -p "${PARENT_DIR}" && [ -d "${PARENT_DIR}" ] \
+        && eval "${3}='${PARENT_DIR}/${REPO_NAME}'" \
+            && notif ok "The repository will be cloned within ${PARENT_DIR}" && return 0 \
+        || { notif err "${PARENT_DIR} does not exist." && return 1 ;}
+}
+
+get-variables-from-file() {
+    # Set the variables contained in a file of key-value pairs
+    export $(grep --invert-match '^#' ${1} | xargs -d '\n')
+}
+
+unset-variables-from-file() {
+    # Removes variables contained in a file of key-value pairs
+    unset $(grep --invert-match '^#' ${1} | \
+            grep --perl-regexp --only-matching '.*(?=\=)' | xargs)
+}
+
+enable-partial-clone() {
+    # Enable partial cloning if a subfolder is provided
+    local CLONE_DIR=${1}
+    local REMOTE_PARTIAL_DIR=${2}
+    [ ${REMOTE_PARTIAL_DIR} ] \
+        && git -C ${CLONE_DIR} config --local extensions.partialClone origin \
+        && git -C ${CLONE_DIR} sparse-checkout set ${REMOTE_PARTIAL_DIR}
+}
+
+fetch-commit-history() {
+    # Fetch history according to the provided commit depth
+    local CLONE_DIR="${1}"
+    local COMMIT_DEPTH="${2}"
+    [ ${COMMIT_DEPTH} ] && [ ${COMMIT_DEPTH} -eq ${COMMIT_DEPTH} ] \
+        && { notif warn "Using COMMIT_DEPTH=${COMMIT_DEPTH}." \
+            && git -C ${CLONE_DIR} fetch --depth ${COMMIT_DEPTH} --filter=blob:none \
+            || abort clean ;} \
+        || { notif warn "COMMIT_DEPTH not provided, fetching all of the history." \
+            && git -C ${CLONE_DIR} fetch --filter=blob:none \
+            || abort clean ;}
+}
+
+pull-single-branch() {
+    local CLONE_DIR=${1}
+    local BRANCH=${2}
+    git -C ${CLONE_DIR} checkout -b $BRANCH
+    git -C ${CLONE_DIR} pull origin $BRANCH \
+        && git -C ${CLONE_DIR} branch --set-upstream-to=origin/$BRANCH ${BRANCH} \
+        || abort clean
+}
+
+pull-all-branches() {
+    # Pull every branch in the remote
+    # and switch to the default branch
+    local CLONE_DIR=${1}
+
+    # Create empty branches
+    N_BRANCHES=$(git -C ${CLONE_DIR} branch -r | wc -l)
+    for ((i=1; i<=$N_BRANCHES; i++)); do
+        BRANCH_NAME_i=$(git -C ${CLONE_DIR} branch -r | \
+                        head -$i | tail -1 | sed s/"origin\/"// | xargs)
+        git -C ${CLONE_DIR} checkout -b $BRANCH_NAME_i
+    done
+
+    # Pull and track every branch
+    for ((i=1; i<=$N_BRANCHES; i++)); do
+        CURRENT_BRANCH=$(git -C ${CLONE_DIR} branch -r | \
+                         head -$i | tail -1 | sed s/"origin\/"// | xargs)
+        git -C ${CLONE_DIR} checkout $CURRENT_BRANCH
+        git -C ${CLONE_DIR} pull origin $CURRENT_BRANCH
+        git -C ${CLONE_DIR} branch --set-upstream-to=origin/$CURRENT_BRANCH ${CURRENT_BRANCH}
+    done
+    HEAD_BRANCH=$(git -C ${CLONE_DIR} remote show origin | \
+                  grep --perl-regexp --only-matching '(?<=HEAD branch: ).*')
+    git checkout ${HEAD_BRANCH}
+}
+
+notif() {
+    # Usage: notif <status> <message>
+    local info='\033[0m'
+    local ok='\033[0;32m'
+    local warn='\033[0;33m'
+    local err='\033[0;31m'
+    local STATUS=${!1}
+    local MSG="${2}"
+    printf $STATUS"${MSG}\n"
+    printf ${info}
+}
+
+abort() {
+    notif err "Aborted."
+    case $# in
+    1)
+        notif warn "Removing empty tree in ${CLONE_DIR}"
+        rm -rf ${CLONE_DIR} && \
+        rmdir -p --ignore-fail-on-non-empty ${CLONE_DIR%/*}
+        ;;
+    esac
+    exit
+}
+
+git-partial-clone ${CONFIG_FILE_PATH}
+

template.conf

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+#
+# Example of the git-partial-clone configuration file
+#
+# Copyright (c) 2021 Lucero Alvarado 
+#   https://github.com/lu0/git-partial-clone
+#
+# THIS FILE DOES NOT SUPPORT INLINE COMMENTS!
+#
+
+GIT_HOST=
+REPO_OWNER=
+REPO_NAME=
+REMOTE_PARTIAL_DIR=
+
+TOKEN_PATH=
+GIT_USER=
+
+BRANCH=
+COMMIT_DEPTH=
+
+PARENT_DIR=
+