add some info for separate compose and execute commands; note about

flaky test
This commit is contained in:
Ian Norden 2019-04-19 10:13:27 -05:00
parent 9c06e9387c
commit 01ffc80ef2
4 changed files with 81 additions and 36 deletions

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@ -108,11 +108,15 @@ These commands are described in detail [here](../staging/documentation/sync.md).
### Data transformation
Contract watchers use the raw data that has been synced into Postgres to filter out and apply transformations to specific data of interest.
There is a built-in `contractWatcher` command which provides generic transformation of most contract data. This command is described in detail [here](../staging/documentation/contractWatcher.md).
There is a built-in `contractWatcher` command which provides generic transformation of most contract data.
The `contractWatcher` command is described further [here](../staging/documentation/contractWatcher.md).
In many cases a custom transformer or set of transformers will need to be written to provide complete or more comprehensive coverage or to optimize other aspects of the output for a specific end-use.
In this case we have provided the `compose`, `execute`, and `composeAndExecute` commands for running custom transformers from external repositories. This is described in detail [here](../staging/documentation/composeAndExecute.md).
In this case we have provided the `compose`, `execute`, and `composeAndExecute` commands for running custom transformers from external repositories.
Usage of the `compose`, `execute`, and `composeAndExecute` commands is described further [here](../staging/documentation/composeAndExecute.md).
Documentation on how to build custom transformers to work with these commands can be found [here](../staging/documentation/transformers.md).
## Tests
- Replace the empty `ipcPath` in the `environments/infura.toml` with a path to a full node's eth_jsonrpc endpoint (e.g. local geth node ipc path or infura url)

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@ -3,48 +3,42 @@ The `composeAndExecute` command is used to compose and execute over an arbitrary
This is accomplished by generating a Go pluggin which allows the `vulcanizedb` binary to link to external transformers, so
long as they abide by one of the standard [interfaces](../staging/libraries/shared/transformer).
This command requires Go 1.11+ and [Go plugins](https://golang.org/pkg/plugin/) only work on Unix-based systems.
Additionally, there are separate `compose` and `execute` commands to allow pre-building and linking to a pre-built .so file.
## Writing custom transformers
Storage Transformers
* [Guide](../../staging/libraries/shared/factories/storage/README.md)
* [Example](../../staging/libraries/shared/factories/storage/EXAMPLE.md)
Event Transformers
* [Guide](../../staging/libraries/shared/factories/event/README.md)
* [Example 1](https://github.com/vulcanize/ens_transformers/tree/master/transformers/registar)
* [Example 2](https://github.com/vulcanize/ens_transformers/tree/master/transformers/registry)
* [Example 3](https://github.com/vulcanize/ens_transformers/tree/master/transformers/resolver)
**NOTE:**
1. It is necessary that the .so file was built with the same exact dependencies that are present in the execution environment,
i.e. we need to `compose` and `execute` the plugin .so file with the same exact version of vulcanizeDB.
1. The plugin migrations are run during the plugin's composition. As such, if `execute` is used to run a prebuilt .so in a different
environment than the one it was composed in then the migrations for that plugin will first need to be manually ran against that environment's Postgres database.
Contract Transformers
* [Example 1](https://github.com/vulcanize/account_transformers)
* [Example 2](https://github.com/vulcanize/ens_transformers/tree/master/transformers/domain_records)
These commands require Go 1.11+ and use [Go plugins](https://golang.org/pkg/plugin/) which only work on Unix-based systems.
There is also an ongoing [conflict](https://github.com/golang/go/issues/20481) between Go plugins and the use vendored dependencies which
imposes certain limitations on how the plugins are built.
## Preparing transformers to work as a plugin for composeAndExecute
To plug in an external transformer we need to:
## Commands
The `compose` and `composeAndExecute` commands assume you are in the vulcanizdb directory located at your system's `$GOPATH`,
and that all of the transformer repositories for building the plugin are present at their `$GOPATH` directories.
1. Create a package that exports a variable `TransformerInitializer`, `StorageTransformerInitializer`, or `ContractTransformerInitializer` that are of type [TransformerInitializer](../staging/libraries/shared/transformer/event_transformer.go#L33)
or [StorageTransformerInitializer](../../staging/libraries/shared/transformer/storage_transformer.go#L31),
or [ContractTransformerInitializer](../../staging/libraries/shared/transformer/contract_transformer.go#L31), respectively
2. Design the transformers to work in the context of their [event](../staging/libraries/shared/watcher/event_watcher.go#L83),
[storage](../../staging/libraries/shared/watcher/storage_watcher.go#L53),
or [contract](../../staging/libraries/shared/watcher/contract_watcher.go#L68) watcher execution modes
3. Create db migrations to run against vulcanizeDB so that we can store the transformer output
* Do not `goose fix` the transformer migrations, this is to ensure they are always ran after the core vulcanizedb migrations which are kept in their fixed form
* Specify migration locations for each transformer in the config with the `exporter.transformer.migrations` fields
* If the base vDB migrations occupy this path as well, they need to be in their `goose fix`ed form
as they are [here](../../staging/db/migrations)
The `execute` command does not require the plugin transformer dependencies be located in their
`$GOPATH` directories, instead it expects a prebuilt .so file (of the name specified in the config file)
to be in `$GOPATH/src/github.com/vulcanize/vulcanizedb/plugins/` and, as noted above, also expects the plugin
db migrations to have already been ran against the database.
To update a plugin repository with changes to the core vulcanizedb repository, replace the vulcanizedb vendored in the plugin repo (`plugin_repo/vendor/github.com/vulcanize/vulcanizedb`)
with the newly updated version
* The entire vendor lib within the vendored vulcanizedb needs to be deleted (`plugin_repo/vendor/github.com/vulcanize/vulcanizedb/vendor`)
* These complications arise due to this [conflict](https://github.com/golang/go/issues/20481) between `dep` and Go plugins
compose:
`./vulcanizedb compose --config=./environments/config_name.toml`
execute:
`./vulcanizedb execute --config=./environments/config_name.toml`
composeAndExecute:
## Configuration
A .toml config file is specified when executing the command:
`./vulcanizedb composeAndExecute --config=./environments/config_name.toml`
The config provides information for composing a set of transformers:
## Configuration
A .toml config file is specified when executing the commands.
The config provides information for composing a set of transformers from external repositories:
```toml
[database]

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@ -0,0 +1,40 @@
# Custom transformers
When the capabilities of the generic `contractWatcher` are not sufficient, custom transformers tailored to a specific
purpose can be leveraged.
Individual transformers can be composed together from any number of external repositories and executed as a single process using
the `compose` and `execute` commands or the `composeAndExecute` command.
## Writing custom transformers
For help with writing different types of custom transformers for the `composeAndExecute` set of commands, please see the below:
Storage Transformers
* [Guide](../../staging/libraries/shared/factories/storage/README.md)
* [Example](../../staging/libraries/shared/factories/storage/EXAMPLE.md)
Event Transformers
* [Guide](../../staging/libraries/shared/factories/event/README.md)
* [Example 1](https://github.com/vulcanize/ens_transformers/tree/master/transformers/registar)
* [Example 2](https://github.com/vulcanize/ens_transformers/tree/master/transformers/registry)
* [Example 3](https://github.com/vulcanize/ens_transformers/tree/master/transformers/resolver)
Contract Transformers
* [Example 1](https://github.com/vulcanize/account_transformers)
* [Example 2](https://github.com/vulcanize/ens_transformers/tree/master/transformers/domain_records)
## Preparing custom transformers to work as part of a plugin
To plug in an external transformer we need to:
1. Create a package that exports a variable `TransformerInitializer`, `StorageTransformerInitializer`, or `ContractTransformerInitializer` that are of type [TransformerInitializer](../staging/libraries/shared/transformer/event_transformer.go#L33)
or [StorageTransformerInitializer](../../staging/libraries/shared/transformer/storage_transformer.go#L31),
or [ContractTransformerInitializer](../../staging/libraries/shared/transformer/contract_transformer.go#L31), respectively
2. Design the transformers to work in the context of their [event](../staging/libraries/shared/watcher/event_watcher.go#L83),
[storage](../../staging/libraries/shared/watcher/storage_watcher.go#L53),
or [contract](../../staging/libraries/shared/watcher/contract_watcher.go#L68) watcher execution modes
3. Create db migrations to run against vulcanizeDB so that we can store the transformer output
* Do not `goose fix` the transformer migrations, this is to ensure they are always ran after the core vulcanizedb migrations which are kept in their fixed form
* Specify migration locations for each transformer in the config with the `exporter.transformer.migrations` fields
* If the base vDB migrations occupy this path as well, they need to be in their `goose fix`ed form
as they are [here](../../staging/db/migrations)
To update a plugin repository with changes to the core vulcanizedb repository, run `dep ensure` to update its dependencies.

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@ -49,6 +49,13 @@ var _ = Describe("contractWatcher light transformer", func() {
c, ok := t.Contracts[tusdAddr]
Expect(ok).To(Equal(true))
// TODO: Fix this
// This test sometimes randomly fails because
// for some reason the starting block number is not updated from
// its original value (5197514) to the block number (6194632)
// of the earliest header (mocks.MockHeader1) in the repository
// It is not clear how this happens without one of the above insertErrs
// having been thrown and without any errors thrown during the Init() call
Expect(c.StartingBlock).To(Equal(int64(6194632)))
Expect(c.Abi).To(Equal(constants.TusdAbiString))
Expect(c.Name).To(Equal("TrueUSD"))