mirror of
https://github.com/grassrootseconomics/cic-chain-events.git
synced 2024-11-22 15:56:45 +01:00
31 lines
1.2 KiB
Markdown
31 lines
1.2 KiB
Markdown
## Functionality
|
|
|
|
### Head syncer
|
|
|
|
Opens a websocket connection and processes live transactions.
|
|
|
|
### Janitor
|
|
|
|
Periodically checks for missed (and historical) blocks missed by the head syncer and queues them for processing. A gap range is processed twice to guarantee there is no missing block.
|
|
|
|
### Pipeline
|
|
|
|
Fetches a block and executes the filters in serial order for every transaction in the block before finally committing the block to the store.
|
|
|
|
### Filter
|
|
|
|
Processes a transaction and passes it on to the next filter or terminates the pipeline for that transaction if it is irrelevant.
|
|
|
|
### Store schema
|
|
|
|
- The `blocks` table keeps track of processed blocks.
|
|
- The `syncer_meta` table keeps track of the lower_bound cursor. Below the lower_bound cursor, all blocks are guarnteed to have been processsed hence it is safe to trim the `blocks` table below that pointer.
|
|
|
|
### GraphQL
|
|
|
|
- Fetches a block (and some of its header details), transactions and transaction receipts embedded within the transaction object in a single call.
|
|
|
|
## Caveats
|
|
|
|
- Blocks are not guaranteed to be processed in order, however a low concurrency setting would somewhat give an "in-order" behaviour (not to be relied upon in any case).
|