#!/usr/bin/env bash

# version 2020-10-20

# IMPORTANT: affects order produced by 'sort' and 'ceph-diff-sorted'
# relies on this ordering
export LANG=C

out_dir="."
temp_file=/tmp/temp.$$
timestamp=$(date -u +%Y%m%d%H%M%S)
lspools_err="${out_dir}/lspools-${timestamp}.error"
rados_out="${out_dir}/rados-${timestamp}.intermediate"
rados_odd="${out_dir}/rados-${timestamp}.issues"
rados_err="${out_dir}/rados-${timestamp}.error"
rgwadmin_out="${out_dir}/radosgw-admin-${timestamp}.intermediate"
rgwadmin_err="${out_dir}/radosgw-admin-${timestamp}.error"
delta_out="${out_dir}/orphan-list-${timestamp}.out"

error_out() {
    echo "An error was encountered while running '$1'. Aborting."
    if [ $# -gt 2 ] ;then
	echo "Error: $3"
    fi
    if [ $# -gt 1 ] ;then
	echo "Review file '$2' for details."
    fi
    echo "***"
    echo "*** WARNING: The results are incomplete. Do not use! ***"
    echo "***"
    exit 1
}

prompt_pool() {
    # note: all prompts go to stderr so stdout contains just the result
    >&2 echo "Available pools:"
    rados lspools >"$temp_file" 2>"$lspools_err"
    if [ "$?" -ne 0 ] ;then
	error_out "rados lspools" "$lspools_err"
    fi
    >&2 sed 's/^/    /' "$temp_file" # list pools and indent
    >&2 printf "Which pool do you want to search for orphans? "
    local mypool
    read mypool
    echo $mypool
}

if [ $# -eq 0 ] ;then
    pool="$(prompt_pool)"
elif [ $# -eq 1 ] ;then
    pool="$1"
else
    error_out "Usage: $0 [pool]"
fi

echo "Pool is \"$pool\"."

echo "Note: output files produced will be tagged with the current timestamp -- ${timestamp}."

echo "running 'rados ls' at $(date)"
# since --format is not specified, plain should be used
rados ls --pool="$pool" --all >"$rados_out" 2>"$rados_err"
if [ "$?" -ne 0 ] ;then
    error_out "rados ls" "$rados_err"
fi

# NOTE: Each entry (line of output) of `rados ls --all` should be in
# one of four formats depending on whether or not an entry has a
# namespace and/or locator:
#
#   <TAB>oid
#   <TAB>oid<TAB>locator
#   namespace<TAB>oid
#   namespace<TAB>oid<TAB>locator
#
# Any occurrences of the 2nd, 3rd, or 4th (i.e., existence of
# namespace and/or locator) should cause the create of the "odd" file
# and an explanation in the output, and those entries will not be
# retained, and therefore they will not be called out as orphans. They
# will need special handling by the end-user as we do not expect
# namespaces or locators.

# check for namespaces -- any line that does not begin with a tab
# indicates a namespace; add those to "odd" file and set flag; note:
# this also picks up entries with namespace and locator
grep $'^[^\t]' "$rados_out" >"$rados_odd"
if [ "${PIPESTATUS[0]}" -eq 0 ] ;then
    namespace_found=1
fi

# check for locators (w/o namespace); we idenitfy them by skipping
# past the empty namespace (i.e., one TAB), skipping past the oid,
# then looking for a TAB; note we use egrep to get the '+' character
# and the $ in front of the ' allows the \t to be interpreted as a TAB
egrep $'^\t[[:graph:]]+\t' "$rados_out" >>"$rados_odd"
if [ "${PIPESTATUS[0]}" -eq 0 ] ;then
    locator_found=1
fi

# extract the entries that are just oids (i.e., no namespace or
# locator) for further processing; only look at lines that begin with
# a TAB and do not contain a second TAB, and then grab everything
# after the initial TAB
grep $'^\t' "$rados_out" | grep -v $'^\t.*\t' | sed -E 's/^\t//' >"$temp_file"
mv -f "$temp_file" "$rados_out"

sort -u "$rados_out" >"$temp_file"
mv -f "$temp_file" "$rados_out"

echo "running 'radosgw-admin bucket radoslist' at $(date)"
radosgw-admin bucket radoslist >"$rgwadmin_out" 2>"$rgwadmin_err"
if [ "$?" -ne 0 ] ;then
    error_out "radosgw-admin radoslist" "$rgwadmin_err"
fi
sort -u "$rgwadmin_out" >"$temp_file"
mv -f "$temp_file" "$rgwadmin_out"

echo "computing delta at $(date)"
ceph-diff-sorted "$rados_out" "$rgwadmin_out" | grep "^<" | sed 's/^< *//' >"$delta_out"
# use PIPESTATUS to get at exit status of first process in above pipe;
# 0 means same, 1 means different, >1 means error
if [ "${PIPESTATUS[0]}" -gt 1 ] ;then
    error_out "ceph-diff-sorted"
fi

found=$(wc -l < "$delta_out")
possible=$(wc -l < "$rados_out")
percentage=0
if [ $possible -ne 0 ] ;then
    percentage=$(expr 100 \* $found / $possible)
fi

echo "$found potential orphans found out of a possible $possible (${percentage}%)."
echo "The results can be found in '${delta_out}'."
echo "    Intermediate files are '${rados_out}' and '${rgwadmin_out}'."
if [ -n "$namespace_found" -o -n "$locator_found" ] ;then
    echo "    Note: 'rados ls' found entries that might be in a namespace or might"
    echo "          have a locator; see '${rados_odd}' for those entries."
fi
echo "***"
echo "*** WARNING: This is EXPERIMENTAL code and the results should be used"
echo "***          only with CAUTION!"
echo "***"
echo "Done at $(date)."