Backup Grafana Dashboards

############################################################ IDENT(1)
#
# $Title: Script to make backup of Grafana dashboards $
# $Copyright: 2019 Devin Teske. All rights reserved. $
# $FrauBSD$
#
############################################################ CONFIGURATION

GRAFANA_DB= /var/lib/grafana/grafana.db
TABLE=      dashboard
KEYS=       slug, data

############################################################ TARGETS

all:
    @sqlite3 $(GRAFANA_DB) 'select $(KEYS) from $(TABLE)' | awk ' \
        function have(name)                                   \
        {                                                     \
            return system(sprintf("type %s > %s 2>&1",    \
                name, "/dev/null")) == 0;             \
        }                                                     \
        function exists(path)                                 \
        {                                                     \
            return system("[ -e " path " ]") == 0;        \
        }                                                     \
        function cat(file,        line, buf)                  \
        {                                                     \
            if (!exists(file)) return "";                 \
            while ((getline line < file) != 0)            \
                buf = buf "\n" line;                  \
            close(file);                                  \
            return substr(buf, 2);                        \
        }                                                     \
        BEGIN {                                               \
            jq = have("jq") ? "jq ." : "cat";             \
        }                                                     \
        match($$0, /\|/) {                                    \
            slug = substr($$0, 1, RSTART - 1);            \
            data = substr($$0, RSTART + 1);               \
            prev = cat(file = slug ".json");              \
            jcmd = sprintf("%s > %s", jq, file);          \
            print data | jcmd;                            \
            close(jcmd);                                  \
            data = cat(file);                             \
            if (data != prev) printf "U %s\n", file;      \
        }                                                     \
    ' # END-QUOTE

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# END
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