Implement a layer system using snippets script

.gitignore

@@ -1,2 +1,2 @@
 README.md.backup
-./tests/profiles/ephemeral.load
+./tests/profiles/ephemeral.profile

.pre-commit-config.yaml

@@ -24,4 +24,4 @@ repos:
         entry: shellcheck
         language: system
         types: [file, shell]
-        files: ^bash_profile_switcher.sh$
+        files: ^(bash_profile_switcher.sh|tests/profiles/snippets/.*\.sh)$

Makefile

@@ -15,6 +15,8 @@ test:
 	shellcheck bash_profile_switcher.sh
 	docker pull bash:5
 	./tests/automated_tests.exp
+format:
+	shfmt -w -i 4 *.sh
 clean:
 	docker-compose down
 install:

README.md

@@ -4,7 +4,8 @@ Easily change environment variables and settings using bash
 ## About
 
 This script aim to manage multiple profile files for bash. It's like having multiple `.bashrc` files to load or unload when needed.
-All you need to do is to create your custom profile files under `~/.bash_profiles` directory. Each profile must have extension `.load` where you define variables, aliases and so on. You can optionally create files with extension `.unload` to clear what is loaded with a speficic profile.
+You need to create your custom profile files under `~/.bash_profile.d` directory. Each profile must have extension `.profile` and it is a plain text file containing a list of "snippets" (one per line) to be loaded into your profile.
+Snippets are `.sh` files where you can set variables/aliases/functions or any command you want to execute when you spawn a shell ([snippet example](examples/snippet-example.sh)).
 
 ## Installation
 
@@ -13,7 +14,7 @@ _Note_: You can use `make install INSTALL_PATH=<path>` to install the script in
 
 ## Usage
 
-Use `switch_profile` function to manage profiles
+Use `switch_profile` function to change profile
 
 ```
  ~]$ switch_profile -h
@@ -29,39 +30,36 @@ OPTIONS
   -l
     List available profiles
   -h Show help instructions (this help)
-
-PROFILE
-  A profile to load in ~/.bash_profiles. Profile files end with extension '.load' for loading (set variables) and '.unload' for unloading (unset variables)
-  Current profile is stored in environment variable BASH_CURRENT_PROFILE and in file ~/.bash_saved_profile
-
-Example:
-
-  ~]$ switch_profile dev
-
-  To load profile dev from ~/.bash_profiles/dev.load and unload it from ~/.bash_profiles/dev.unload
 ```
 
 ## Example
 
-Create the following profile files in `~/.bash_profiles`:
-
-> `myprofile.load`
-
-```bash
-export PS1="Funky Prompt:: \w ]\\$ "
+As an example take the following directory structure for `~/.bash_profile.d`
+```
+.bash_profile.d/
+├── foo.profile
+├── bar.profile
+└── snippets
+    ├── tools.sh
+    ├── cloudvars.sh
+    └── setpath.sh
 ```
 
-> `myprofile.unload`
-
-```bash
-unset PS1
 ```
-Then load it with: `switch_profile myprofile`
+]$ cat ~/.bash_profile.d/foo.profile
+tools
+cloudvars
+setpath
+]$ cat ~/.bash_profile.d/bar.profile
+setpath
+```
 
+When you do `switch_profile foo` snippets `tools.sh`,`cloudvars.sh`,`setpath.sh` will be loaded (in the same order they are listed in profile).
+On profile change `switch_profile bar` bash will first unload all the snippets applied by `foo` in reverse order then load the snippets listed in `bar`, that is `setpath.sh`
+``
 ## Issues
 
 * Spaces and blank characters are not supported on profile filenames
-* Unload files must be written manually to match exactly what you loaded or defined
 * Be careful when managing special variables like `PATH`
 
 ## Test automation

bash_profile_switcher.sh

@@ -29,24 +29,80 @@
 ### GENERAL CONFIGURATION ###
 
 # Setup default directory
-export SWITCH_PROFILE_DIRECTORY=".bash_profiles"
+export SWITCH_PROFILE_DIRECTORY=".bash_profile.d"
 [ -d "$HOME/$SWITCH_PROFILE_DIRECTORY" ] || mkdir "$HOME/$SWITCH_PROFILE_DIRECTORY"
+[ -d "$HOME/$SWITCH_PROFILE_DIRECTORY/snippets" ] || mkdir "$HOME/$SWITCH_PROFILE_DIRECTORY/snippets"
+
 # Setup save profile filename
 export SWITCH_PROFILE_SAVED=".bash_saved_profile"
 
+# List of loaded snippets separated by colon like
+# snipname1:snipname2:snippetname3
+export SWITCH_PROFILE_SNIPPETS=""
+
 # Setup aliases to manage profiles
-alias _load_bash_profile='eval [ -f "$HOME/$SWITCH_PROFILE_DIRECTORY/${BASH_CURRENT_PROFILE}.load" ] && source "$HOME/$SWITCH_PROFILE_DIRECTORY/${BASH_CURRENT_PROFILE}.load"'
-alias _unload_bash_profile='eval [ -f "$HOME/$SWITCH_PROFILE_DIRECTORY/${BASH_CURRENT_PROFILE}.unload" ] && source "$HOME/$SWITCH_PROFILE_DIRECTORY/${BASH_CURRENT_PROFILE}.unload"'
-alias _save_bash_profile='eval echo "export BASH_CURRENT_PROFILE=$SELECTED_PROFILE" > "$HOME/$SWITCH_PROFILE_SAVED"'
-alias _reset_bash_profile='eval echo "unset BASH_CURRENT_PROFILE" > "$HOME/$SWITCH_PROFILE_SAVED"'
+alias _save_bash_profile='eval echo "export SWITCH_PROFILE_CURRENT=$SELECTED_PROFILE" > "$HOME/$SWITCH_PROFILE_SAVED"'
+alias _reset_bash_profile='eval echo "unset SWITCH_PROFILE_CURRENT" > "$HOME/$SWITCH_PROFILE_SAVED"'
+
+alias _get_snippets='eval unset LOAD_SNIPPETS; declare -a LOAD_SNIPPETS; mapfile -c 1 -C _parse_profile -t <"${HOME}/${SWITCH_PROFILE_DIRECTORY}/${SWITCH_PROFILE_CURRENT}.profile"'
+# shellcheck disable=SC2154
+alias _load_bash_profile='_get_snippets; for ((n=0;n<${#LOAD_SNIPPETS[*]};n++)); do source "${LOAD_SNIPPETS[$n]}" load; done'
+alias _unload_bash_profile='for ((n=-1;n>=-${#LOAD_SNIPPETS[*]};n--)); do source "${LOAD_SNIPPETS[$n]}" unload; done'
+
+# _parse_profile
+# To be used with mapfile
+# Every line in the file is parsed and checked for a corresponding snippet to be loaded
+# It will store the valid snippets in global array LOAD_SNIPPETS
+_parse_profile() {
+    local VALUE
+    local SNIPPET
+    VALUE="$2"
+    if [[ "$VALUE" =~ ^[[:blank:]]*([^# ]+)([[:blank:]]|$) ]]; then
+        {
+            SNIPPET="${BASH_REMATCH[1]}"
+            [ -f "$HOME/$SWITCH_PROFILE_DIRECTORY/snippets/$SNIPPET.sh" ] && LOAD_SNIPPETS+=("$HOME/$SWITCH_PROFILE_DIRECTORY/snippets/$SNIPPET.sh")
+        }
+    fi
+    return 0
+}
+
+# _snippet [push|pop|search] <snippet name>
+# Manage the status of snippets storing it in SWITCH_PROFILE_SNIPPETS if it has loaded or unloaded.
+# - push the snippet name into SWITCH_PROFILE_SNIPPETS only if the value is not already present
+# - pop the snippet name from SWITCH_PROFILE_SNIPPETS
+# - search if a snippet name is present in SWITCH_PROFILE_SNIPPETS
+_snippet() {
+    local -r snippet_cmd="${1:-}"
+    local -r snippet_name="${2:-}"
+    local -r REGEX="(^|.*:)(${snippet_name})(:.*|$)"
+
+    case "$snippet_cmd" in
+    push)
+        if [[ "$SWITCH_PROFILE_SNIPPETS" =~ $REGEX ]]; then return 0; else SWITCH_PROFILE_SNIPPETS="${SWITCH_PROFILE_SNIPPETS}:${snippet_name}"; fi
+        export SWITCH_PROFILE_SNIPPETS=${SWITCH_PROFILE_SNIPPETS#:}
+        ;;
+    pop)
+        if [[ "$SWITCH_PROFILE_SNIPPETS" =~ $REGEX ]]; then SWITCH_PROFILE_SNIPPETS="${BASH_REMATCH[1]%:}:${BASH_REMATCH[3]#:}"; else return 0; fi
+        SWITCH_PROFILE_SNIPPETS=${SWITCH_PROFILE_SNIPPETS%:}
+        export SWITCH_PROFILE_SNIPPETS=${SWITCH_PROFILE_SNIPPETS#:}
+        ;;
+    search)
+        if [[ "$SWITCH_PROFILE_SNIPPETS" =~ $REGEX ]]; then return 0; else return 1; fi
+        ;;
+    *)
+        echo "${SWITCH_PROFILE_SNIPPETS:-}"
+        ;;
+    esac
+    return 0
+}
 
-# Create list of profiles from .load files
+# Create list of profiles from .profile files
 _switch_profile_list() {
     local PROFILE_LIST
-    # Note: If there are no matching files, echo *.load output literally "*.load"
-    PROFILE_LIST="$(echo "$HOME/$SWITCH_PROFILE_DIRECTORY/"*.load)"
+    # Note: If there are no matching files, echo *.profile output literally "*.profile"
+    PROFILE_LIST="$(echo "$HOME/$SWITCH_PROFILE_DIRECTORY/"*.profile)"
     PROFILE_LIST="${PROFILE_LIST//$HOME\/$SWITCH_PROFILE_DIRECTORY\//}"
-    PROFILE_LIST="${PROFILE_LIST//.load/}"
+    PROFILE_LIST="${PROFILE_LIST//.profile/}"
     [ "$PROFILE_LIST" = '*' ] && PROFILE_LIST=""
     echo "$PROFILE_LIST"
 }
@@ -71,14 +127,39 @@ OPTIONS
   -h Show help instructions (this help)
 
 PROFILE
-  A profile to load in ~/.bash_profiles. Profile files end with extension '.load' for loading (set variables) and '.unload' for unloading (unset variables)
-  Current profile is stored in environment variable BASH_CURRENT_PROFILE and in file ~/.bash_saved_profile
+  A profile to load in ~/$SWITCH_PROFILE_DIRECTORY. Profile files end with extension '.profile' and contains a list of snippets to be loaded.
+  Current profile is stored in environment variable SWITCH_PROFILE_CURRENT and in file ~/$SWITCH_PROFILE_SAVED
 
-Example:
+SNIPPETS
+
+  Snippets are .sh files located in ~/$SWITCH_PROFILE_DIRECTORY/snippets that accept load or unload as first positional parameter (\$1)
+  Each snippet will be included with source in your shell.
+
+EXAMPLE
+
+  Given the following setup ~/$SWITCH_PROFILE_DIRECTORY
+  ~]$ tree ~/.bash_profile.d/
+    $HOME/.bash_profile.d/
+    ├── dev.profile
+    └── snippets
+        ├── snip1.sh
+        └── snip2.sh
+
+  ~]$ cat ~/.bash_profile.d/dev.profile
+    snip1
+    snip2
 
   ~]$ switch_profile dev
 
-  To load profile dev from ~/.bash_profiles/dev.load and unload it from ~/.bash_profiles/dev.unload
+  snip1.sh and snip2.sh will be included into your bash shell.
+
+ADDENDUM
+
+  - Snippets will be loaded in the order the are listed into profile file.
+  - When you switch into a profile snippets are loaded with source command e.g. 'source snip1 load'
+  - When you change profile, current snippets are unloaded (except if you use -k) in reverse order
+    they are listed into profile file with source e.g. 'source snip1 unload'
+
 
 EOF
 }
@@ -122,9 +203,9 @@ switch_profile() {
     shift $((OPTIND - 1))
 
     SELECTED_PROFILE="$1"
-    if [ -f "${HOME}/${SWITCH_PROFILE_DIRECTORY}/${SELECTED_PROFILE}.load" ]; then {
+    if [ -f "${HOME}/${SWITCH_PROFILE_DIRECTORY}/${SELECTED_PROFILE}.profile" ]; then {
         [ $KEEP_ENV -eq 0 ] && _unload_bash_profile
-        if [ $TEMP_PROFILE -eq 0 ]; then _save_bash_profile; else export BASH_NEXT_PROFILE="$SELECTED_PROFILE"; fi
+        if [ $TEMP_PROFILE -eq 0 ]; then _save_bash_profile; else export SWITCH_PROFILE_NEXT="$SELECTED_PROFILE"; fi
         exec bash
     }; else
         {
@@ -140,18 +221,18 @@ switch_profile() {
 ### MAIN SCRIPT ###
 [ -n "$SWITCH_PROFILE_LIST" ] && complete -o nospace -W "$SWITCH_PROFILE_LIST" switch_profile
 
-if [ -z ${BASH_NEXT_PROFILE+is_set} ]; then {
+if [ -z ${SWITCH_PROFILE_NEXT+is_set} ]; then {
     if [ -f "$HOME/$SWITCH_PROFILE_SAVED" ]; then
         {
             # shellcheck source=/dev/null
             source "$HOME/$SWITCH_PROFILE_SAVED"
-            [ -n "${BASH_CURRENT_PROFILE+is_set}" ] && _load_bash_profile
+            if [ -n "${SWITCH_PROFILE_CURRENT+is_set}" ]; then _load_bash_profile; fi
         }
     fi
 }; else
     {
-        export BASH_CURRENT_PROFILE="$BASH_NEXT_PROFILE"
-        unset BASH_NEXT_PROFILE
+        export SWITCH_PROFILE_CURRENT="$SWITCH_PROFILE_NEXT"
+        unset SWITCH_PROFILE_NEXT
         _load_bash_profile
     }
 fi

docker-compose.yml

@@ -17,5 +17,5 @@ services:
         read_only: true
       - type: bind
         source: $PWD/tests/profiles/
-        target: /root/.bash_profiles/
+        target: /root/.bash_profile.d/
         read_only: true

examples/snippet-example.sh

@@ -0,0 +1,23 @@
+# shellcheck shell=bash
+SNIPPET_NAME="$(basename "${BASH_SOURCE[0]}" .sh)"
+case "$1" in
+load)
+    _snippet search "$SNIPPET_NAME" && return 0
+    # load your settings here >>>
+    export var1="test1 variable"
+    # <<<
+    _snippet push "$SNIPPET_NAME" 2>/dev/null
+    ;;
+unload)
+    _snippet search "$SNIPPET_NAME" || return 0
+    # unload your settings here >>>
+    unset var1
+    # <<<
+    _snippet pop "$SNIPPET_NAME" 2>/dev/null
+    ;;
+*)
+    true
+    ;;
+esac
+
+return 0

tests/automated_tests.exp

@@ -14,6 +14,7 @@ proc print_results {} {
 
 proc abort {} {
     print_results
+    sleep 1
     send "exit\n"
     send "exit\n"
     sleep 1
@@ -35,7 +36,9 @@ source ./tests/scenarios/06-temporary-profile.exp
 source ./tests/scenarios/07-keep-profile.exp
 source ./tests/scenarios/08-unexistent-profile.exp
 source ./tests/scenarios/09-reload-list.exp
+source ./tests/scenarios/10-check-snippet.exp
 
+sleep 1
 send "exit\n"
 sleep 1
 print_results

tests/profiles/snippets/varcommon.sh

@@ -0,0 +1,17 @@
+# shellcheck shell=bash
+SNIPPET_NAME="varcommon"
+case "$1" in
+load)
+    export check_var_common="${common_value:-}"
+    _snippet push "$SNIPPET_NAME" 2>/dev/null
+    ;;
+unload)
+    unset check_var_common
+    _snippet pop "$SNIPPET_NAME" 2>/dev/null
+    ;;
+*)
+    true
+    ;;
+esac
+
+return 0

tests/profiles/snippets/vartest1.sh

@@ -0,0 +1,19 @@
+# shellcheck shell=bash
+SNIPPET_NAME="$(basename "${BASH_SOURCE[0]}" .sh)"
+case "$1" in
+load)
+    export check_var_test1="test1 variable"
+    export common_value="test1 common"
+    _snippet push "$SNIPPET_NAME" 2>/dev/null
+    ;;
+unload)
+    unset check_var_test1
+    unset common_value
+    _snippet pop "$SNIPPET_NAME" 2>/dev/null
+    ;;
+*)
+    true
+    ;;
+esac
+
+return 0

tests/profiles/snippets/vartest2.sh

@@ -0,0 +1,19 @@
+# shellcheck shell=bash
+SNIPPET_NAME="$(basename "${BASH_SOURCE[0]}" .sh)"
+case "$1" in
+load)
+    export check_var_test2="test2 variable"
+    export common_value="test2 common"
+    _snippet push "$SNIPPET_NAME" 2>/dev/null
+    ;;
+unload)
+    unset check_var_test2
+    unset common_value
+    _snippet pop "$SNIPPET_NAME" 2>/dev/null
+    ;;
+*)
+    true
+    ;;
+esac
+
+return 0

tests/profiles/test1.profile

@@ -0,0 +1,5 @@
+# comment and spaces will be stripped
+   # out while parsing the configuration
+
+             vartest1
+ varcommon # also if you comment the single snippet name

tests/profiles/test2.profile

@@ -0,0 +1,2 @@
+vartest2
+varcommon