Umbrella Project Organization

How the BlockScout project is organized

BlockScout is an Elixir umbrella project. Each directory under apps/ is a separate Mix project and OTP application, but the projects can use each other as a dependency in their mix.exs.
Each OTP application has a restricted domain. 
Table is horizontally scrollable.
Directory
OTP Application
Namespace
Purpose
apps/ethereum_jsonrpc
:ethereum_jsonrpc
EthereumJSONRPC
Ethereum JSONRPC client.  It is allowed to know Explorer's param format, but it cannot directly depend on :explorer
apps/explorer
:explorer
Explorer
Storage for the indexed chain.  Can read and write to the backing storage.  MUST be able to boot in a read-only mode when run independently from :indexer, so cannot depend on :indexer as that would start :indexer indexing.
apps/block_scout_web
:block_scout_web
BlockScoutWeb
Phoenix interface to :explorer.  The minimum interface to allow web access should go in :block_scout_web.  Any business rules or interface not tied directly to Phoenix or Plug should go in :explorer. MUST be able to boot in a read-only mode when run independently from :indexer, so cannot depend on :indexer as that would start :indexer indexing.
apps/indexer
:indexer
Indexer
Uses :ethereum_jsonrpc to index chain and batch import data into :explorer.  Any process, Task, or GenServer that automatically reads from the chain and writes to :explorer should be in :indexer. This restricts automatic writes to :indexer and read-only mode can be achieved by not running :indexer.

Separate Indexer, Web App, and API

Deployment Differences Between Chains

Last modified 3yr ago

Directory	OTP Application	Namespace	Purpose
`apps/ethereum_jsonrpc`	`:ethereum_jsonrpc`	`EthereumJSONRPC`	Ethereum JSONRPC client. It is allowed to know `Explorer`'s param format, but it cannot directly depend on `:explorer`
`apps/explorer`	`:explorer`	`Explorer`	Storage for the indexed chain. Can read and write to the backing storage. MUST be able to boot in a read-only mode when run independently from `:indexer`, so cannot depend on `:indexer` as that would start `:indexer` indexing.
`apps/block_scout_web`	`:block_scout_web`	`BlockScoutWeb`	Phoenix interface to `:explorer`. The minimum interface to allow web access should go in `:block_scout_web`. Any business rules or interface not tied directly to `Phoenix` or `Plug` should go in `:explorer`. MUST be able to boot in a read-only mode when run independently from `:indexer`, so cannot depend on `:indexer` as that would start `:indexer` indexing.
`apps/indexer`	`:indexer`	`Indexer`	Uses `:ethereum_jsonrpc` to index chain and batch import data into `:explorer`. Any process, `Task`, or `GenServer` that automatically reads from the chain and writes to `:explorer` should be in `:indexer`. This restricts automatic writes to `:indexer` and read-only mode can be achieved by not running `:indexer`.