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pearify

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This commit is contained in:
dmc
2024-01-31 23:43:56 +01:00
parent 3b4264dea3
commit 95145e31cd
4 changed files with 73 additions and 58 deletions
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30
howto/replicate-and-persist-with-hypercore.md
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@@ -2,7 +2,7 @@
In the HyperDHT How-to ([Connect Two Peers](./connect-two-peers-by-key-with-hyperdht.md)) and the Hyperswarm How-to ([Connect Many Peers](./connect-to-many-peers-by-topic-with-hyperswarm.md)), peers can exchange chat messages so long as both are online at the same time and directly connected. The application is ephemeral, the messages are not persisted - they will be lost if the recipient is offline. Hypercore provides the persistence.
[Hypercore](../building-blocks/hypercore.md) is a secure, distributed append-only log. It is built for sharing enormous datasets and streams of real-time data. It has a secure transport protocol, making it easy to build fast and scalable peer-to-peer applications.
[`Hypercore`](../building-blocks/hypercore.md) is a secure, distributed append-only log. It is built for sharing enormous datasets and streams of real-time data. It has a secure transport protocol, making it easy to build fast and scalable peer-to-peer applications.
Now extend the ephemeral chat example above but using Hypercore to add many significant new features:
@@ -20,12 +20,12 @@ Create the `writer-app` project with these commands:
mkdir writer-app
cd writer-app
pear init -y -t terminal
npm install hypercore hyperswarm b4a
```
Alter the generated `writer-app/index.js` to the following:
```javascript
import path from 'path'
import Hyperswarm from 'hyperswarm'
import Hypercore from 'hypercore'
import b4a from 'b4a'
@@ -33,7 +33,7 @@ import b4a from 'b4a'
const swarm = new Hyperswarm()
Pear.teardown(() => swarm.destroy())
const core = new Hypercore(path.join(Pear.config.storage, 'writer-storage'))
const core = new Hypercore(Pear.config.storage)
// core.key and core.discoveryKey will only be set after core.ready resolves
await core.ready()
@@ -57,6 +57,7 @@ Create the `reader-app` project with these commands:
mkdir reader-app
cd reader-app
pear init -y -t terminal
npm install hypercore hyperswarm
```
Alter the generated `reader-app/index.js` to the following:
@@ -65,12 +66,11 @@ Alter the generated `reader-app/index.js` to the following:
```javascript
import Hyperswarm from 'hyperswarm'
import Hypercore from 'hypercore'
import goodbye from 'graceful-goodbye'
const swarm = new Hyperswarm()
goodbye(() => swarm.destroy())
Pear.teardown(() => swarm.destroy())
const core = new Hypercore('./reader-storage', process.argv[2])
const core = new Hypercore(Pear.config.storage, process.argv[2])
await core.ready()
const foundPeers = core.findingPeers()
@@ -94,22 +94,20 @@ for await (const block of core.createReadStream({ start: core.length, live: true
}
```
There should now be two folders, `writer-app` and `reader-app`.
In one terminal run:
In one terminal, open `writer-app` with `pear dev`.
```
pear dev ./writer-app
cd writer-app
pear dev
```
If the `writer-app` is not in the current dir, adjust the path to point to `writer-app`.
The `writer-app` will output the Hypercore key.
In another terminal run
In another terminal, open the `reader-app` and pass it the key:
```
pear dev ./reader-app
cd reader-app
pear dev -- <SUPPLY THE KEY HERE>
```
Again if the `reader-app` is not in the current dir, adjust the path to point to `reader-app`.
As inputs are made to the terminal running the writer application, outputs should be shown in the terminal running the reader application.
As inputs are made to the terminal running the writer application, outputs should be shown in the terminal running the reader application.