From de9b0660acf26edc3b261b805c1a3454e3c76321 Mon Sep 17 00:00:00 2001 From: Anton Evangelatov Date: Tue, 7 Aug 2018 12:56:01 +0200 Subject: [PATCH] swarm/README: add more sections to easily onboard developers (#17333) --- swarm/README.md | 191 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 190 insertions(+), 1 deletion(-) diff --git a/swarm/README.md b/swarm/README.md index f2d189043..e81963217 100644 --- a/swarm/README.md +++ b/swarm/README.md @@ -7,6 +7,21 @@ Swarm is a distributed storage platform and content distribution service, a nati [![Travis](https://travis-ci.org/ethereum/go-ethereum.svg?branch=master)](https://travis-ci.org/ethereum/go-ethereum) [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ethersphere/orange-lounge?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) +## Table of Contents + +* [Building the source](#building-the-source) +* [Running Swarm](#running-swarm) +* [Documentation](#documentation) +* [Developers Guide](#developers-guide) + * [Go Environment](#development-environment) + * [Vendored Dependencies](#vendored-dependencies) + * [Testing](#testing) + * [Profiling Swarm](#profiling-swarm) + * [Metrics and Instrumentation in Swarm](#metrics-and-instrumentation-in-swarm) +* [Public Gateways](#public-gateways) +* [Swarm Dapps](#swarm-dapps) +* [Contributing](#contributing) +* [License](#license) ## Building the source @@ -16,13 +31,187 @@ Building Swarm requires Go (version 1.10 or later). go install github.com/ethereum/go-ethereum/cmd/swarm +## Running Swarm + +Going through all the possible command line flags is out of scope here, but we've enumerated a few common parameter combos to get you up to speed quickly on how you can run your own Swarm node. + +To run Swarm you need an Ethereum account. You can create a new account by running the following command: + + geth account new + +You will be prompted for a password: + + Your new account is locked with a password. Please give a password. Do not forget this password. + Passphrase: + Repeat passphrase: + +Once you have specified the password, the output will be the Ethereum address representing that account. For example: + + Address: {2f1cd699b0bf461dcfbf0098ad8f5587b038f0f1} + +Using this account, connect to Swarm with + + swarm --bzzaccount + + # in our example + + swarm --bzzaccount 2f1cd699b0bf461dcfbf0098ad8f5587b038f0f1 + + +### Verifying that your local Swarm node is running + +When running, Swarm is accessible through an HTTP API on port 8500. + +Confirm that it is up and running by pointing your browser to http://localhost:8500 + +### Ethereum Name Service resolution + +The Ethereum Name Service is the Ethereum equivalent of DNS in the classic web. In order to use ENS to resolve names to Swarm content hashes (e.g. `bzz://theswarm.eth`), `swarm` has to connect to a `geth` instance, which is synced with the Ethereum mainnet. This is done using the `--ens-api` flag. + + swarm --bzzaccount \ + --ens-api '$HOME/.ethereum/geth.ipc' + + # in our example + + swarm --bzzaccount 2f1cd699b0bf461dcfbf0098ad8f5587b038f0f1 \ + --ens-api '$HOME/.ethereum/geth.ipc' + +For more information on usage, features or command line flags, please consult the Documentation. + ## Documentation Swarm documentation can be found at [https://swarm-guide.readthedocs.io](https://swarm-guide.readthedocs.io). -## Contribution +## Developers Guide + +### Go Environment + +We assume that you have Go v1.10 installed, and `GOPATH` is set. + +You must have your working copy under `$GOPATH/src/github.com/ethereum/go-ethereum`. + +Most likely you will be working from your fork of `go-ethereum`, let's say from `github.com/nirname/go-ethereum`. Clone or move your fork into the right place: + +``` +git clone git@github.com:nirname/go-ethereum.git $GOPATH/src/github.com/ethereum/go-ethereum +``` + + +### Vendored Dependencies + +All dependencies are tracked in the `vendor` directory. We use `govendor` to manage them. + +If you want to add a new dependency, run `govendor fetch `, then commit the result. + +If you want to update all dependencies to their latest upstream version, run `govendor fetch +v`. + + +### Testing + +This section explains how to run unit, integration, and end-to-end tests in your development sandbox. + +Testing one library: + +``` +go test -v -cpu 4 ./swarm/api +``` + +Note: Using options -cpu (number of cores allowed) and -v (logging even if no error) is recommended. + +Testing only some methods: + +``` +go test -v -cpu 4 ./eth -run TestMethod +``` + +Note: here all tests with prefix TestMethod will be run, so if you got TestMethod, TestMethod1, then both! + +Running benchmarks: + +``` +go test -v -cpu 4 -bench . -run BenchmarkJoin +``` + + +### Profiling Swarm + +This section explains how to add Go `pprof` profiler to Swarm + +If `swarm` is started with the `--pprof` option, a debugging HTTP server is made available on port 6060. + +You can bring up http://localhost:6060/debug/pprof to see the heap, running routines etc. + +By clicking full goroutine stack dump (clicking http://localhost:6060/debug/pprof/goroutine?debug=2) you can generate trace that is useful for debugging. + + +### Metrics and Instrumentation in Swarm + +This section explains how to visualize and use existing Swarm metrics and how to instrument Swarm with a new metric. + +Swarm metrics system is based on the `go-metrics` library. + +The most common types of measurements we use in Swarm are `counters` and `resetting timers`. Consult the `go-metrics` documentation for full reference of available types. + +``` +# incrementing a counter +metrics.GetOrRegisterCounter("network.stream.received_chunks", nil).Inc(1) + +# measuring latency with a resetting timer +start := time.Now() +t := metrics.GetOrRegisterResettingTimer("http.request.GET.time"), nil) +... +t := UpdateSince(start) +``` + +#### Visualizing metrics + +Swarm supports an InfluxDB exporter. Consult the help section to learn about the command line arguments used to configure it: + +``` +swarm --help | grep metrics +``` + +We use Grafana and InfluxDB to visualise metrics reported by Swarm. We keep our Grafana dashboards under version control at `./swarm/grafana_dashboards`. You could use them or design your own. + +We have built a tool to help with automatic start of Grafana and InfluxDB and provisioning of dashboards at https://github.com/nonsense/stateth , which requires that you have Docker installed. + +Once you have `stateth` installed, and you have Docker running locally, you have to: + +1. Run `stateth` and keep it running in the background +``` +stateth --rm --grafana-dashboards-folder $GOPATH/src/github.com/ethereum/go-ethereum/swarm/grafana_dashboards --influxdb-database metrics +``` + +2. Run `swarm` with at least the following params: +``` +--metrics \ +--metrics.influxdb.export \ +--metrics.influxdb.endpoint "http://localhost:8086" \ +--metrics.influxdb.username "admin" \ +--metrics.influxdb.password "admin" \ +--metrics.influxdb.database "metrics" +``` + +3. Open Grafana at http://localhost:3000 and view the dashboards to gain insight into Swarm. + + +## Public Gateways + +Swarm offers a local HTTP proxy API that Dapps can use to interact with Swarm. The Ethereum Foundation is hosting a public gateway, which allows free access so that people can try Swarm without running their own node. + +The Swarm public gateways are temporary and users should not rely on their existence for production services. + +The Swarm public gateway can be found at https://swarm-gateways.net and is always running the latest `stable` Swarm release. + +## Swarm Dapps + +You can find a few reference Swarm decentralised applications at: https://swarm-gateways.net/bzz:/swarmapps.eth + +Their source code can be found at: https://github.com/ethersphere/swarm-dapps + +## Contributing Thank you for considering to help out with the source code! We welcome contributions from anyone on the internet, and are grateful for even the smallest of fixes!