Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Get records from a AWS Kinesis Data Stream. It allows you to start iterating from a time in the past.
#!/usr/bin/env bash
if ! aws_bin="$(which aws)" 2>/dev/null; then
echo "aws cli is missing; you can get it from https://aws.amazon.com/cli/"
exit 1
fi
if ! jq_bin="$(which jq)" 2>/dev/null; then
echo "jq is missing; you can get it from https://stedolan.github.io/jq/"
exit 1
fi
# print partition-key for each record
: "${print_pk:=0}"
: "${debug_aws_commands:=0}"
aws() {
if [[ "$debug_aws_commands" == 1 ]]; then
echo "aws $*" 1>&2
fi
"$aws_bin" "$@"
}
jq() {
"$jq_bin" "$@"
}
# trap ctrl-c and call ctrl_c()
trap ctrl_c INT
shutdown_now=0
ctrl_c() {
shutdown_now=1
}
# set to LATEST for latest or a relative-time in the past using "date string"
# specifier as described under "DATE STRING" in `man date`
: "${time:=LATEST}"
if [[ "$time" == LATEST ]]; then
time_spec=($time)
else
time_spec=(AT_TIMESTAMP --timestamp "$(date +%s -d "$time").000")
fi
get_shards() {
aws kinesis describe-stream --stream-name "$1" |
jq -r '.StreamDescription.Shards[].ShardId'
}
get_shard_iterators() {
for shard in $(get_shards "$1"); do
aws kinesis get-shard-iterator --stream-name "$1" --shard-id "$shard" \
--shard-iterator-type "${time_spec[@]}" |
jq -r '.ShardIterator'
done
}
iterate() {
iterator="$1"
while [[ "$shutdown_now" == 0 ]] && [ -n "$iterator" ]; do
if ! op="$(aws kinesis get-records --shard-iterator "$iterator")"; then
sleep 1
continue
fi
jq -r '.Records[]|(.PartitionKey + "\t" + .Data)' <<<"$op" |
while IFS=$'\t' read -ra rec; do
if [[ "$print_pk" == 1 ]]; then
echo -e "\\nPK: ${rec[0]}"
else
echo
fi
base64 -d <<<"${rec[1]}"
done
iterator="$(jq -r '.NextShardIterator' <<<"$op")"
msBehind="$(jq -r '.MillisBehindLatest' <<<"$op")"
if [[ "$msBehind" == 0 ]]; then
sleep 2
else
sleep .5
fi
done
}
if [ -z "$1" ] || [[ "$1" == help ]]; then
cat <<HELP
Usage: $(basename "$0") <StreamName>
Under the hood, this tool uses aws-cli. This means that all environment variables
and shared-credentials setup will work with this too.
You can specify the relative time from NOW, to start the iterator.
Example:
# Iterate and get records from the Kinesis stream "PlayerData"
# under "profile-name-1" profile, starting from 10mins ago
AWS_PROFILE=profile-name-1 time="10 mins ago" ./$(basename "$0") PlayerData
HELP
exit 0
fi
for itr in $(get_shard_iterators "$1"); do
iterate "$itr" &
done
wait
@codemedic

This comment has been minimized.

Copy link
Owner Author

@codemedic codemedic commented Mar 7, 2019

The usage is explained in its help, which is accessible as a sub-command.

Usage: kinesis-get-records.sh <StreamName>

Under the hood, this tool uses aws-cli. This means that all environment variables
and shared-credentials setup will work with this too.

You can specify a relative time from NOW, to start the iterator.

If you need to see the Partition Key (PK) for each record, set "print_pk=1".

Example:
    # Iterate and get records from the Kinesis stream "PlayerData"
    # under "profile-name-1" profile, starting from 10mins ago
    # prints PK for each record
    AWS_PROFILE=profile-name-1 time="10 mins ago" print_pk=1 ./kinesis-get-records.sh PlayerData
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.