git ssb

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const { each, map } = require('libnested')
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const onceTrue = require('mutant/once-true')
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const watch = require('mutant/watch')
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const Value = require('mutant/value')
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const assert = require('assert')
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const Defer = require('pull-defer').source
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// auto-inject the ssb-server to all methods to reduce repitition
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module.exports = function inject (server, methods, pluginDeps = []) {
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  checkMethods(methods)
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  switch (typeof server) {
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    case 'object': // just a classic ssb server
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      checkPlugins(server, pluginDeps)
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      return map(methods, (fn, path) => fn(server))
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    case 'function': // hopefully an observeable which will contain an ssb server
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      return injectObsServer(server, methods)
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    default:
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      throw new Error('scuttle-poll expects an ssb server (or obs that contains one)')
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  }
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}
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function injectObsServer (server, methods, pluginDeps = []) {
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  onceTrue(server, server => checkPlugins(server, pluginDeps))
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  return map(methods, (fn, path) => {
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    if (path.includes('async')) {
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      return function () {
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        onceTrue(
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          server,
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          server => fn(server).apply(null, arguments)
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        )
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      }
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    }
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    if (path.includes('pull')) {
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      return function () {
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        const source = Defer()
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        onceTrue(
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          server,
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          server => {
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            var _source = fn(server).apply(null, arguments)
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            source.resolve(_source)
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          }
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        )
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        return source
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      }
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    }
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    // NOTE - both `obs` and `sync` methods will return observeables
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    return function () {
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      var result = Value({})
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      // var result = Struct({}) // WARNING - this shouldn't be copied for other apps, only works with obs.get method here. Probably breaks sync.isBlog
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      onceTrue(
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        server,
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        server => {
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          var res = fn(server).apply(null, arguments)
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          watch(res, res => result.set(res))
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        }
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      )
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      return result
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    }
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  })
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}
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function checkMethods (methods) {
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  const server = { backlinks: 'fake' }
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  each(methods, (fn, path) => {
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    assert(typeof fn === 'function', `${path.join('.')}: expect each method to be a function`)
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    const injectedMethod = fn(server)
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    assert(typeof injectedMethod === 'function', `${path.join('.')}: expect each method to be a closure which accepts a server and returns a function`)
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  })
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}
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function checkPlugins (server, pluginDeps) {
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  pluginDeps.forEach(p => {
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    if (!server[p]) throw new Error(`scuttle-blog needs a scuttlebot server with the ${p} plugin installed`)
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  })
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}
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