Merge pull request #2 from Mindgrub/feature/1/step-functions-support

feat: Add step functions support, resolves #1

Dockerfile

@@ -1,6 +1,6 @@
-FROM alpine:3.15
+FROM alpine:3.18
 
-RUN apk add --no-cache mysql-client python3 py3-pip coreutils \
+RUN apk add --no-cache mysql-client python3 py3-pip coreutils jq \
     && pip install awscli
 
 ADD run.sh /run.sh

README.md

@@ -15,10 +15,11 @@ An Alpine-based Docker image for producing a file with `mysqldump` and uploading
 - `S3_PREFIX` – Optional. A string to prepend to the S3 object key (Default: "").
 - `MYSQL_NET_BUFFER_LENGTH` – Optional. The `net_buffer_length` setting for `mysqldump` (Default: "16384").
 - `REQUESTOR` – Optional. The email address of the user who requested this dump to be stored in the S3 metadata.
+- `SFN_TASK_TOKEN` – Optional. A Step Functions [Task Token](https://docs.aws.amazon.com/step-functions/latest/apireference/API_GetActivityTask.html#StepFunctions-GetActivityTask-response-taskToken). If present, this token will be used to call [`SendTaskHeartbeat`](https://docs.aws.amazon.com/step-functions/latest/apireference/API_SendTaskHeartbeat.html) and [`SendTaskSuccess`](https://docs.aws.amazon.com/step-functions/latest/apireference/API_SendTaskSuccess.html). The task output sent to `SendTaskSuccess` will consist of a JSON object with a single property: `uri` (containing the S3 URI of the database dump).
 
 ### AWS Permissions
 
-If this Docker image is used within Amazon ECS, specify permissions to S3 within your Task Definition role. Otherwise, you can provide `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` as environment variables.
+If this Docker image is used within Amazon ECS, specify permissions to S3 (and optionally Step Functions) within your Task Definition role. Otherwise, you can provide `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` as environment variables.
 
 ## Technical Details
 

run.sh

@@ -1,6 +1,11 @@
 #!/bin/sh
 set -e
 
+# Send heartbeat
+if [ -n "$SFN_TASK_TOKEN" ]; then
+  aws stepfunctions send-task-heartbeat --task-token "$SFN_TASK_TOKEN"
+fi
+
 # Variable defaults
 : "${FILENAME_PREFIX:=snapshot}"
 : "${MYSQL_NET_BUFFER_LENGTH:=16384}"
@@ -18,12 +23,22 @@ echo "About to export mysql://$DB_HOST/$DB_NAME to $destination"
 mysqldump -h "$DB_HOST" -u "$DB_USER" --password="$DB_PASS" -P "$DB_PORT" -R -E --triggers --single-transaction --comments --net-buffer-length="$MYSQL_NET_BUFFER_LENGTH" "$DB_NAME" | gzip > "$destination"
 echo "Export to $destination completed"
 
+# Send heartbeat
+if [ -n "$SFN_TASK_TOKEN" ]; then
+  aws stepfunctions send-task-heartbeat --task-token "$SFN_TASK_TOKEN"
+fi
+
+# Publish to S3
 extra_metadata=""
 if [ -n "$REQUESTOR" ]; then
     extra_metadata=",Requestor=$REQUESTOR"
 fi
-
-# Publish to S3
 echo "About to upload $destination to $s3_url"
 aws s3 cp "$destination" "$s3_url" --storage-class "$S3_STORAGE_TIER" --metadata "DatabaseHost=${DB_HOST},DatabaseName=${DB_NAME}${extra_metadata}"
 echo "Upload to $s3_url completed"
+
+# Send activity success
+if [ -n "$SFN_TASK_TOKEN" ]; then
+  json_output=$(jq -cn --arg uri "$s3_url" '{"uri":$uri}')
+  aws stepfunctions send-task-success --task-token "$SFN_TASK_TOKEN" --task-output "$json_output"
+fi