summaryrefslogtreecommitdiff
path: root/utils/lib.sh
blob: 818477fc3a6f3429c52945a23372039541c3b3b2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
#!/usr/bin/env bash
# -*- coding: utf-8; mode: sh indent-tabs-mode: nil -*-
# SPDX-License-Identifier: AGPL-3.0-or-later
# shellcheck disable=SC2059,SC1117

ADMIN_NAME="${ADMIN_NAME:-$(git config user.name)}"
ADMIN_NAME="${ADMIN_NAME:-$USER}"

ADMIN_EMAIL="${ADMIN_EMAIL:-$(git config user.email)}"
ADMIN_EMAIL="${ADMIN_EMAIL:-$USER@$(hostname)}"

if [[ -z "${REPO_ROOT}" ]]; then
    REPO_ROOT=$(dirname "${BASH_SOURCE[0]}")
    while [ -h "${REPO_ROOT}" ] ; do
        REPO_ROOT=$(readlink "${REPO_ROOT}")
    done
    REPO_ROOT=$(cd "${REPO_ROOT}/.." && pwd -P )
fi

if [[ -z ${TEMPLATES} ]]; then
    TEMPLATES="${REPO_ROOT}/utils/templates"
fi

if [[ -z "$CACHE" ]]; then
    CACHE="${REPO_ROOT}/cache"
fi

if [[ -z ${DIFF_CMD} ]]; then
    DIFF_CMD="diff -u"
    if command -v colordiff >/dev/null;  then
        DIFF_CMD="colordiff -u"
    fi
fi

DOT_CONFIG="${DOT_CONFIG:-${REPO_ROOT}/.config}"

source_dot_config() {
    if [[ ! -e "$DOT_CONFIG" ]]; then
        info_msg "installing $DOT_CONFIG"
        cp "$(dirname "${BASH_SOURCE[0]}")/dot_config" "$DOT_CONFIG"
        if [[ ! -z ${SUDO_USER} ]]; then
            chown "${SUDO_USER}:${SUDO_USER}" "$DOT_CONFIG"
        fi
    fi
    # shellcheck disable=SC1090
    source "${REPO_ROOT}/.config"
}

sudo_or_exit() {
    # usage: sudo_or_exit

    if [ ! "$(id -u)" -eq 0 ];  then
        err_msg "this command requires root (sudo) privilege!" >&2
        exit 42
    fi
}

required_commands() {

    # usage:  requires_commands [cmd1 ...]

    local exit_val=0
    while [ ! -z "$1" ]; do

        if ! command -v "$1" &>/dev/null; then
            err_msg "missing command $1"
            exit_val=42
        fi
        shift
    done
    return $exit_val
}

# colors
# ------

# shellcheck disable=SC2034
set_terminal_colors() {
    _colors=8
    _creset='\e[0m'  # reset all attributes

    _Black='\e[0;30m'
    _White='\e[1;37m'
    _Red='\e[0;31m'
    _Green='\e[0;32m'
    _Yellow='\e[0;33m'
    _Blue='\e[0;34m'
    _Violet='\e[0;35m'
    _Cyan='\e[0;36m'

    _BBlack='\e[1;30m'
    _BWhite='\e[1;37m'
    _BRed='\e[1;31m'
    _BGreen='\e[1;32m'
    _BYellow='\e[1;33m'
    _BBlue='\e[1;34m'
    _BPurple='\e[1;35m'
    _BCyan='\e[1;36m'
}
set_terminal_colors

# reST
# ----

if command -v fmt >/dev/null; then
    export FMT="fmt -u"
else
    export FMT="cat"
fi

rst_title() {
    # usage: rst_title <header-text> [part|chapter|section]

    case ${2-chapter} in
        part)     printf "\n${_BGreen}${1//?/=}\n${_BCyan}${1}${_BGreen}\n${1//?/=}${_creset}\n";;
        chapter)  printf "\n${_BCyan}${1}\n${_BGreen}${1//?/=}${_creset}\n";;
        section)  printf "\n${_BCyan}${1}\n${_BGreen}${1//?/-}${_creset}\n";;
        *)
            err_msg "invalid argument '${2}' in line $(caller)"
            return 42
            ;;
    esac
}

rst_para() {
    # usage:  RST_INDENT=1 rst_para "lorem ipsum ..."
    local prefix=''
    if ! [[ -z $RST_INDENT ]] && [[ $RST_INDENT -gt 0 ]]; then
        prefix="$(for i in $(seq 1 "$RST_INDENT"); do printf "  "; done)"
        echo -en "\n$*\n" | $FMT | prefix_stdout "$prefix"
    else
        echo -en "\n$*\n" | $FMT
    fi
}

err_msg()  { echo -e "${_BRed}ERROR:${_creset} $*" >&2; }
warn_msg() { echo -e "${_BBlue}WARN:${_creset}  $*" >&2; }
info_msg() { echo -e "${_BYellow}INFO:${_creset}  $*" >&2; }

clean_stdin() {
    if [[ $(uname -s) != 'Darwin' ]]; then
        while read -r -n1 -t 0.1; do : ; done
    fi
}

wait_key(){
    # usage: waitKEY [<timeout in sec>]

    clean_stdin
    local _t=$1
    local msg="${MSG}"
    [[ -z "$msg" ]] && msg="${_Green}** press any [${_BCyan}KEY${_Green}] to continue **${_creset}"

    [[ ! -z $FORCE_TIMEOUT ]] && _t=$FORCE_TIMEOUT
    [[ ! -z $_t ]] && _t="-t $_t"
    printf "$msg"
    # shellcheck disable=SC2086
    read -r -s -n1 $_t
    echo
    clean_stdin
}

ask_yn() {
    # usage: ask_yn <prompt-text> [Ny|Yn] [<timeout in sec>]

    local EXIT_YES=0 # exit status 0 --> successful
    local EXIT_NO=1  # exit status 1 --> error code

    local _t=$3
    [[ ! -z $FORCE_TIMEOUT ]] && _t=$FORCE_TIMEOUT
    [[ ! -z $_t ]] && _t="-t $_t"
    case "${FORCE_SELECTION:-${2}}" in
        Y) return ${EXIT_YES} ;;
        N) return ${EXIT_NO} ;;
        Yn)
            local exit_val=${EXIT_YES}
            local choice="[${_BGreen}YES${_creset}/no]"
            local default="Yes"
            ;;
        *)
            local exit_val=${EXIT_NO}
            local choice="[${_BGreen}NO${_creset}/yes]"
            local default="No"
            ;;
    esac
    echo
    while true; do
        clean_stdin
        printf "$1 ${choice} "
        # shellcheck disable=SC2086
        read -r -n1 $_t
        if [[ -z $REPLY ]]; then
            printf "$default\n"; break
        elif [[ $REPLY =~ ^[Yy]$ ]]; then
            exit_val=${EXIT_YES}
            printf "\n"
            break
        elif [[ $REPLY =~ ^[Nn]$ ]]; then
            exit_val=${EXIT_NO}
            printf "\n"
            break
        fi
        _t=""
        err_msg "invalid choice"
    done
    clean_stdin
    return $exit_val
}

tee_stderr () {

    # usage::
    #   tee_stderr 1 <<EOF | python -i
    #   print("hello")
    #   EOF
    #   ...
    #   >>> print("hello")
    #    hello

    local _t="0";
    if [[ ! -z $1 ]] ; then _t="$1"; fi

    (while read -r line; do
         # shellcheck disable=SC2086
         sleep $_t
         echo -e "$line" >&2
         echo "$line"
    done)
}

prefix_stdout () {
    # usage: <cmd> | prefix_stdout [prefix]

    local prefix="${_BYellow}-->|${_creset}"

    if [[ ! -z $1 ]] ; then prefix="${_BYellow}$1${_creset}"; fi

    # shellcheck disable=SC2162
    (while IFS= read line; do
        echo -e "${prefix}$line"
    done)
}

append_line() {

    # usage: append_line <line> <file>
    #
    # Append line if not exists, create file if not exists. E.g::
    #
    #     append_line 'source ~/.foo' ~/bashrc

    local LINE=$1
    local FILE=$2
    grep -qFs -- "$LINE" "$FILE" || echo "$LINE" >> "$FILE"
}

cache_download() {

    # usage: cache_download <url> <local-filename>

    local exit_value=0

    if [[ ! -z ${SUDO_USER} ]]; then
        sudo -u "${SUDO_USER}" mkdir -p "${CACHE}"
    else
        mkdir -p "${CACHE}"
    fi

    if [[ -f "${CACHE}/$2" ]] ; then
        info_msg "already cached: $1"
        info_msg "  --> ${CACHE}/$2"
    fi

    if [[ ! -f "${CACHE}/$2" ]]; then
        info_msg "caching: $1"
        info_msg "  --> ${CACHE}/$2"
        if [[ ! -z ${SUDO_USER} ]]; then
            sudo -u "${SUDO_USER}" wget --progress=bar -O "${CACHE}/$2" "$1" ; exit_value=$?
        else
            wget --progress=bar -O "${CACHE}/$2" "$1" ; exit_value=$?
        fi
        if [[ $exit_value = 0 ]]; then
            err_msg "failed to download: $1"
        fi
    fi
}

choose_one() {

    # usage:
    #
    #   DEFAULT_SELECT= 2 \
    #     choose_one <name> "your selection?" "Coffee" "Coffee with milk"

    local default=${DEFAULT_SELECT-1}
    local REPLY
    local env_name=$1 && shift
    local choice=$1;
    local max="${#@}"
    local _t
    [[ ! -z $FORCE_TIMEOUT ]] && _t=$FORCE_TIMEOUT
    [[ ! -z $_t ]] && _t="-t $_t"

    list=("$@")
    echo -e "${_BGreen}Menu::${_creset}"
    for ((i=1; i<= $((max -1)); i++)); do
        if [[ "$i" == "$default" ]]; then
            echo -e "  ${_BGreen}$i.${_creset}) ${list[$i]} [default]"
        else
            echo -e "  $i.) ${list[$i]}"
        fi
    done
    while true; do
        clean_stdin
        printf "$1 [${_BGreen}$default${_creset}] "

        if (( 10 > max )); then
            # shellcheck disable=SC2086
            read -r -n1 $_t
        else
            # shellcheck disable=SC2086,SC2229
            read -r $_t
        fi
        # selection fits
        [[ $REPLY =~ ^-?[0-9]+$ ]] && (( REPLY > 0 )) && (( REPLY < max )) && break

        # take default
        [[ -z $REPLY ]] && REPLY=$default && break

        _t=""
        err_msg "invalid choice"
    done
    eval "$env_name"='${list[${REPLY}]}'
    echo
    clean_stdin
}

install_template() {

    # usage:
    #
    #     install_template [--no-eval] [--variant=<name>] \
    #                      {file} [{owner} [{group} [{chmod}]]]
    #
    # E.g. the origin of variant 'raw' of /etc/updatedb.conf is::
    #
    #    ${TEMPLATES}/etc/updatedb.conf:raw
    #
    # To install variant 'raw' of /etc/updatedb.conf without evaluated
    # replacements you can use::
    #
    #    install_template --variant=raw --no-eval \
    #                     /etc/updatedb.conf root root 644

    local _reply=""
    local do_eval=1
    local variant=""
    local pos_args=("$0")

    for i in "$@"; do
        case $i in
            --no-eval) do_eval=0; shift ;;
            --variant=*) variant=":${i#*=}"; shift ;;
            *) pos_args+=("$i") ;;
        esac
    done

    local dst="${pos_args[1]}"
    local template_origin="${TEMPLATES}${dst}${variant}"
    local template_file="${TEMPLATES}${dst}"

    local owner="${pos_args[2]-$(id -un)}"
    local group="${pos_args[3]-$(id -gn)}"
    local chmod="${pos_args[4]-644}"

    info_msg "install (eval=$do_eval): ${dst}"
    [[ ! -z $variant ]] && info_msg "variant: ${variant}"

    if [[ ! -f "${template_origin}" ]] ; then
        err_msg "${template_origin} does not exists"
        err_msg "... can't install $dst"
        wait_key 30
        return 42
    fi

    if [[ "$do_eval" == "1" ]]; then
        template_file="${CACHE}${dst}${variant}"
        info_msg "BUILD template ${template_file}"
        if [[ ! -z ${SUDO_USER} ]]; then
            sudo -u "${SUDO_USER}" mkdir -p "$(dirname "${template_file}")"
        else
            mkdir -p "$(dirname "${template_file}")"
        fi
        # shellcheck disable=SC2086
        eval "echo \"$(cat ${template_origin})\"" > "${template_file}"
        if [[ ! -z ${SUDO_USER} ]]; then
            chown "${SUDO_USER}:${SUDO_USER}" "${template_file}"
        fi
    else
        template_file=$template_origin
    fi

    mkdir -p "$(dirname "${dst}")"

    if [[ ! -f "${dst}" ]]; then
        info_msg "install: ${template_file}"
        sudo -H install -v -o "${owner}" -g "${group}" -m "${chmod}" \
             "${template_file}" "${dst}" | prefix_stdout
        return $?
    fi

    if [[ -f "${dst}" ]] && cmp --silent "${template_file}" "${dst}" ; then
        info_msg "file ${dst} allready installed"
        return 0
    fi

    info_msg "diffrent file ${dst} allready exists on this host"

    while true; do
        choose_one _reply "choose next step with file $dst" \
                   "replace file" \
                   "leave file unchanged" \
                   "interactiv shell" \
                   "diff files"

        case $_reply in
            "replace file")
                info_msg "install: ${template_file}"
                sudo -H install -v -o "${owner}" -g "${group}" -m "${chmod}" \
                     "${template_file}" "${dst}" | prefix_stdout
                break
                ;;
            "leave file unchanged")
                break
                ;;
            "interactiv shell")
                echo "// edit ${dst} to your needs"
                echo -e "// exit with [${_BCyan}CTRL-D${_creset}]"
                sudo -H -u "${owner}" -i
                $DIFF_CMD "${dst}" "${template_file}"
                echo
                echo "${_BBlack}did you edit file ...${_creset}"
                printf "  ${template_file}"
                if ask_yn "... to your needs?"; then
                    break
                fi
                ;;
            "diff files")
                $DIFF_CMD "${dst}" "${template_file}" | prefix_stdout
        esac
    done
}


service_is_available() {

    # usage:  service_is_available <URL>

    local URL="$1"
    if [[ -z $URL ]]; then
        err_msg "service_is_available: missing arguments"
        return 42
    fi

    http_code=$(curl -H 'Cache-Control: no-cache' \
         --silent -o /dev/null --head --write-out '%{http_code}' --insecure \
         "${URL}")
    exit_val=$?
    if [[ $exit_val = 0 ]]; then
        info_msg "got $http_code from ${URL}"
    fi
    case "$http_code" in
        404|410|423) exit_val=$http_code;;
    esac
    return "$exit_val"
}

# golang
# ------

go_is_available() {

    # usage:  go_is_available $SERVICE_USER && echo "go is installed!"

    sudo -i -u "${1}" which go &>/dev/null
}

install_go() {

    # usage:  install_go "${GO_PKG_URL}" "${GO_TAR}" "${SERVICE_USER}"

    local _svcpr="  |${3}| "

    rst_title "Install Go in user's HOME" section

    rst_para "download and install go binary .."
    cache_download "${1}" "${2}"

    tee_stderr 0.1 <<EOF | sudo -i -u "${3}" | prefix_stdout "$_svcpr"
echo \$PATH
echo \$GOPATH
mkdir -p \$HOME/local
rm -rf \$HOME/local/go
tar -C \$HOME/local -xzf ${CACHE}/${2}
EOF
    sudo -i -u "${3}" <<EOF | prefix_stdout
! which go >/dev/null &&  echo "ERROR - Go Installation not found in PATH!?!"
which go >/dev/null &&  go version && echo "congratulations -- Go installation OK :)"
EOF
}

# system accounts
# ---------------

service_account_is_available() {

    # usage:  service_account_is_available "$SERVICE_USER" && echo "OK"

    sudo -i -u "$1" echo \$HOME &>/dev/null
}

drop_service_account() {

    # usage:  drop_service_account "${SERVICE_USER}"

    rst_title "Drop ${1} HOME" section
    if ask_yn "Do you really want to drop ${1} home folder?"; then
        userdel -r -f "${1}" 2>&1 | prefix_stdout
    else
        rst_para "Leave HOME folder $(du -sh "${1}") unchanged."
    fi
}

interactive_shell(){

    # usage:  interactive_shell "${SERVICE_USER}"

    echo -e "// exit with [${_BCyan}CTRL-D${_creset}]"
    sudo -H -u "${1}" -i
}


# systemd
# -------

SYSTEMD_UNITS="${SYSTEMD_UNITS:-/lib/systemd/system}"

systemd_install_service() {

    # usage:  systemd_install_service "${SERVICE_NAME}" "${SERVICE_SYSTEMD_UNIT}"

    rst_title "Install System-D Unit ${1}" section
    echo
    install_template "${2}" root root 644
    wait_key
    systemd_activate_service "${1}"
}

systemd_remove_service() {

    # usage:  systemd_remove_service "${SERVICE_NAME}" "${SERVICE_SYSTEMD_UNIT}"

    if ! ask_yn "Do you really want to deinstall systemd unit ${1}?"; then
        return 42
    fi
    systemd_deactivate_service "${1}"
    rm "${2}"  2>&1 | prefix_stdout
}

systemd_activate_service() {

    # usage:  systemd_activate_service "${SERVICE_NAME}"w

    rst_title "Activate ${1} (service)" section
    echo
    tee_stderr <<EOF | bash 2>&1
systemctl enable  ${1}.service
systemctl restart ${1}.service
EOF
    tee_stderr <<EOF | bash 2>&1
systemctl status --no-pager ${1}.service
EOF
}

systemd_deactivate_service() {

    # usage:  systemd_deactivate_service "${SERVICE_NAME}"

    rst_title "De-Activate ${1} (service)" section
    echo
    tee_stderr <<EOF | bash 2>&1 | prefix_stdout
systemctl stop    ${1}.service
systemctl disable ${1}.service
EOF
}


# Apache
# ------

# FIXME: Arch Linux & RHEL should be added

if [[ -z "${APACHE_SITES_AVAILABE}" ]]; then
    APACHE_SITES_AVAILABE="/etc/apache2/sites-available"
fi

apache_is_installed() {
    (command -v apachectl \
        && command -v a2ensite \
        && command -v a2dissite ) &>/dev/null
}

apache_reload() {

    info_msg "reload apache .."
    echo
    sudo -H apachectl configtest
    sudo -H service apache2 force-reload
}

apache_install_site() {

    # usage:  apache_install_site [<template option> ...] <mysite.conf>
    #
    # <template option>:   see install_template

    local template_opts=()
    local pos_args=("$0")

    for i in "$@"; do
        case $i in
            -*) template_opts+=("$i");;
            *)  pos_args+=("$i");;
        esac
    done

    install_template "${template_opts[@]}" \
                     "${APACHE_SITES_AVAILABE}/${pos_args[1]}" \
                     root root 644

    apache_enable_site "${pos_args[1]}"
    info_msg "installed apache site: ${pos_args[1]}"
}

apache_remove_site() {

    # usage:  apache_remove_site <mysite.conf>

    info_msg "remove apache site: $1"
    apache_dissable_site "$1"
    rm -f "${APACHE_SITES_AVAILABE}/$1"
}

apache_enable_site() {

    # usage:  apache_enable_site <mysite.conf>

    info_msg "enable apache site: $1"
    sudo -H a2ensite -q "$1"
    apache_reload
}

apache_dissable_site() {

    # usage:  apache_disable_site <mysite.conf>

    info_msg "disable apache site: $1"
    sudo -H a2dissite -q "$1"
    apache_reload
}

# uWSGI
# -----

uWSGI_SETUP="${uWSGI_SETUP:=/etc/uwsgi}"

uWSGI_restart() {

    # usage:  uWSGI_restart()

    info_msg "restart uWSGI service"
    systemctl restart uwsgi
}

uWSGI_app_available() {
    # usage:  uWSGI_app_available <myapp.ini>
    local CONF="$1"
    if [[ -z $CONF ]]; then
        err_msg "uWSGI_app_available: missing arguments"
        return 42
    fi
    [[ -f "${uWSGI_SETUP}/apps-available/${CONF}" ]]
}

uWSGI_install_app() {

    # usage:  uWSGI_install_app [<template option> ...] <myapp.ini>
    #
    # <template option>:  see install_template

    local pos_args=("$0")

    for i in "$@"; do
        case $i in
            -*) template_opts+=("$i");;
            *)  pos_args+=("$i");;
        esac
    done

    install_template "${template_opts[@]}" \
                     "${uWSGI_SETUP}/apps-available/${pos_args[1]}" \
                     root root 644

    uWSGI_enable_app "${pos_args[1]}"
    uWSGI_restart
    info_msg "installed uWSGI app: ${pos_args[1]}"
}

uWSGI_remove_app() {

    # usage:  uWSGI_remove_app <myapp.ini>

    local CONF="$1"
    info_msg "remove uWSGI app: ${CONF}"
    uWSGI_disable_app "${CONF}"
    uWSGI_restart
    rm -f "${uWSGI_SETUP}/apps-available/${CONF}"
}

uWSGI_app_enabled() {
    # usage:  uWSGI_app_enabled <myapp.ini>
    local CONF="$1"
    if [[ -z $CONF ]]; then
        err_msg "uWSGI_app_enabled: missing arguments"
        return 42
    fi
    [[ -f "${uWSGI_SETUP}/apps-enabled/${CONF}" ]]
}

# shellcheck disable=SC2164
uWSGI_enable_app() {

    # usage:   uWSGI_enable_app <myapp.ini>

    local CONF="$1"
    if [[ -z $CONF ]]; then
        err_msg "uWSGI_enable_app: missing arguments"
        return 42
    fi
    pushd "${uWSGI_SETUP}/apps-enabled" >/dev/null
    rm -f "$CONF"
    # shellcheck disable=SC2226
    ln -s "../apps-available/${CONF}"
    info_msg "enabled uWSGI app: ${CONF} (restart uWSGI required)"
    popd >/dev/null
}

uWSGI_disable_app() {

    # usage:   uWSGI_disable_app <myapp.ini>

    local CONF="$1"
    if [[ -z $CONF ]]; then
        err_msg "uWSGI_enable_app: missing arguments"
        return 42
    fi
    rm -f "${uWSGI_SETUP}/apps-enabled/${CONF}"
    # FIXME: restart uwsgi service won't stop wsgi forked processes of user searx.
    # I had to kill them manually here ...
    pkill -f "${uWSGI_SETUP}/apps-enabled/${CONF}" -9
    info_msg "disabled uWSGI app: ${CONF} (restart uWSGI required)"
}

# distro's package manager
# ------------------------
#
# FIXME: Arch Linux & RHEL should be added
#

pkg_install() {

    # usage: TITEL='install foobar' pkg_install foopkg barpkg

    rst_title "${TITLE:-installation of packages}" section
    echo -en "\npackage(s)::\n\n  $*\n" | $FMT

    if ! ask_yn "Should packages be installed?" Yn 30; then
        return 42
    fi
    # shellcheck disable=SC2068
    apt-get install -y $@
}

pkg_remove() {

    # usage: TITEL='remove foobar' pkg_remove foopkg barpkg

    rst_title "${TITLE:-remove packages}" section
    echo -en "\npackage(s)::\n\n  $*\n" | $FMT

    if ! ask_yn "Should packages be removed (purge)?" Yn 30; then
        return 42
    fi
    apt-get purge --autoremove --ignore-missing -y "$@"
}

pkg_is_installed() {

    # usage: pkg_is_install foopkg || pkg_install foopkg

    dpkg -l "$1" &> /dev/null
    return $?
}

# git tooling
# -----------

# shellcheck disable=SC2164
git_clone() {

    # usage:
    #
    #    git_clone <url> <name> [<branch> [<user>]]
    #    git_clone <url> <path> [<branch> [<user>]]
    #
    #  First form uses $CACHE/<name> as destination folder, second form clones
    #  into <path>.  If repository is allready cloned, pull from <branch> and
    #  update working tree (if needed, the caller has to stash local changes).
    #
    #    git clone https://github.com/asciimoo/searx searx-src origin/master searxlogin
    #

    local url="$1"
    local dest="$2"
    local branch="$3"
    local user="$4"
    local bash_cmd="bash"
    local remote="origin"

    if [[ ! "${dest:0:1}" = "/" ]]; then
        dest="$CACHE/$dest"
    fi

    [[ -z $branch ]] && branch=master
    [[ -z $user ]] && [[ ! -z "${SUDO_USER}" ]] && user="${SUDO_USER}"
    [[ ! -z $user ]] && bash_cmd="sudo -H -u $user -i"

    if [[ -d "${dest}" ]] ; then
        info_msg "already cloned: $dest"
        tee_stderr 0.1 <<EOF | $bash_cmd 2>&1 |  prefix_stdout "  |$user| "
cd "${dest}"
git checkout -m -B "$branch" --track "$remote/$branch"
git pull --all
EOF
    else
        info_msg "clone into: $dest"
        tee_stderr 0.1 <<EOF | $bash_cmd 2>&1 |  prefix_stdout "  |$user| "
mkdir -p "$(dirname "$dest")"
cd "$(dirname "$dest")"
git clone --branch "$branch" --origin "$remote" "$url" "$(basename "$dest")"
EOF
    fi
}