Docker: How to create a table for local dynamo DB? - docker

Question

I'm trying to create a docker container with local Amazon Dynamo DB. And it actually works. But I can not understand how to create a table for this image in Docker file?
Through the javascript I create a table like this:
var params = {
TableName: 'UserActivity',
KeySchema: [
{
AttributeName: 'user_id',
KeyType: 'HASH',
},
{
AttributeName: 'user_action',
KeyType: 'RANGE',
}
],
AttributeDefinitions: [
{
AttributeName: 'user_id',
AttributeType: 'S',
},
{
AttributeName: 'user_action',
AttributeType: 'S',
}
],
ProvisionedThroughput: {
ReadCapacityUnits: 2,
WriteCapacityUnits: 2,
}
};
dynamodb.createTable(params, function(err, data) {
if (err) ppJson(err); // an error occurred
else ppJson(data); // successful response
});
And here is my Docker file:
FROM openjdk:8-jre-alpine
ENV DYNAMODB_VERSION=latest
RUN apk add --update curl && \
rm -rf /var/cache/apk/* && \
curl -O https://s3-us-west-2.amazonaws.com/dynamodb-local/dynamodb_local_${DYNAMODB_VERSION}.tar.gz && \
tar zxvf dynamodb_local_${DYNAMODB_VERSION}.tar.gz && \
rm dynamodb_local_${DYNAMODB_VERSION}.tar.gz
EXPOSE 8000
ENTRYPOINT ["java", "-Djava.library.path=.", "-jar", "DynamoDBLocal.jar", "--sharedDb", "-inMemory", "-port", "8000"]

Answer 1

You need to point your DynamoDB client to the local DynamoDB endpoint.
Do something like:
dynamodb = new AWS.DynamoDB({
endpoint: new AWS.Endpoint('http://localhost:8000')
});
dynamodb.createTable(...);
UPDATE
Alternatively you can use AWS CLI to create tables in your local DynamoDB without using JavaSciprt code. You need to use the "--endpoint-url" to point CLI to your local instance like this:
aws dynamodb list-tables --endpoint-url http://localhost:8000
You need to use create-table command to create a table.

Answer 2

The main problem was in base image which I used for local dynamodb. I mean openjdk:8-jre-alpine
Looks like the alpine distribution does not have something important for functioning of local dynamodb.
So here is a working Dockerfile for local dynamodb:
FROM openjdk:8-jre
ENV DYNAMODB_VERSION=latest
COPY .aws/ root/.aws/
RUN curl -O https://s3-us-west-2.amazonaws.com/dynamodb-local/dynamodb_local_${DYNAMODB_VERSION}.tar.gz && \
tar zxvf dynamodb_local_${DYNAMODB_VERSION}.tar.gz && \
rm dynamodb_local_${DYNAMODB_VERSION}.tar.gz
EXPOSE 8000
ENTRYPOINT ["java", "-Djava.library.path=.", "-jar", "DynamoDBLocal.jar", "--sharedDb", "-inMemory"]
I'd be happy to read what is the main problem of alpine in this particular case.