Introduction

This is about the Docker images created for Flowee

Flowee the Hub provides a lot of services and the most convenient way to run, maintain and expand your service level is by marrying Flowee with Docker containers.

Both in Flowee as well as in Docker there is a way of thinking where you can start one unit and it becomes easy to connect this to with services or to connect your application to them.

Additionally, adding new instances (called containers) of the application is made simple using the Docker user interface or one of its front-ends (like portainer).

Flowee services network together

The strength of Flowee applications comes from deploying the set of services you need, each in its own Docker container, and networking them together. You can start a new indexer anywhere on your network and as such making great uptime one step closer.

Networking in Docker needs a bit of understanding. The main mistake made is to use localhost for connecting to another container just because they are running on the same host machine.

You need to understand that each Docker container is like a virtual machine and ‘localhost’ is completely local to one container. So your Indexer’s localhost is a different one from your Hub’s localhost.

The known to work approach is for each Flowee container (hub, indexer, etc) to expose the API as a port on your host machine and then let others connect to your host machine. Either directly on the current IP address, or if your host machine is reachable by (local) DNS, use that name.

If you use a name make sure it actually resolves using DNS, not via your hosts config (/etc/hosts) as that is not available to docker containers.

Lets run through an example;

For instance your machine is called DockerServer and has IP address 192.168.0.2 on your subnet. Other machines in your subnet can ‘ping’ your machine using DockerServer as a name.

Starting Hub with the docker argument -p 1235:1245 makes its API service available for all machines on the subnet, including all docker containers.

Starting Indexer with the docker argument -e FLOWEE_HUB=DockerServer will make the indexer connect properly.

If your IP is stable, you can try to pass the IP address instead: -e FLOWEE_HUB=192.168.0.2 .

Services overview

The center of Flowee is always (the hub). This is where the block are stored, where the transactions live.

Docker, Explanation

Then the most important component is the Indexer. this component provides fast lookup indexes on the raw data stored by the Hub. Want to find a transaction by its TxID? You can ask the Indexer and with the location it returns you ask the Hub for the actual transaction data.

Docker, Explanation

As the first usecase driven services there is the bitcore-proxy, a JSON providing API used by many block explorers.

Bitcore is a product from BitPay and its known to be difficult to setup and maintain. At the same time it was one of the first of its kind and this means there are a lot of usages for it. Flowee provides the proxy service which is meant to be a drop-in replacement that is much faster to setup.

Docker, Explanation

The pos-cli is a A point-of-sale (test) tool to get updates for address usage.

Docker