[misc] rewrite: free functions

libraries/redis-wrapper/index.js

@@ -6,7 +6,6 @@
  * DS207: Consider shorter variations of null checks
  * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
  */
-let RedisSharelatex
 const _ = require('underscore')
 const os = require('os')
 const crypto = require('crypto')
@@ -17,130 +16,125 @@ const PID = process.pid
 const RND = crypto.randomBytes(4).toString('hex')
 let COUNT = 0
 
-module.exports = RedisSharelatex = {
-  createClient(opts) {
-    let client, standardOpts
-    if (opts == null) {
-      opts = { port: 6379, host: 'localhost' }
+function createClient(opts) {
+  let client, standardOpts
+  if (opts == null) {
+    opts = { port: 6379, host: 'localhost' }
+  }
+  if (opts.retry_max_delay == null) {
+    opts.retry_max_delay = 5000 // ms
+  }
+
+  if (opts.cluster != null) {
+    const Redis = require('ioredis')
+    standardOpts = _.clone(opts)
+    delete standardOpts.cluster
+    delete standardOpts.key_schema
+    client = new Redis.Cluster(opts.cluster, standardOpts)
+    client.healthCheck = clusterHealthCheckBuilder(client)
+    _monkeyPatchIoredisExec(client)
+  } else {
+    standardOpts = _.clone(opts)
+    const ioredis = require('ioredis')
+    client = new ioredis(standardOpts)
+    _monkeyPatchIoredisExec(client)
+    client.healthCheck = singleInstanceHealthCheckBuilder(client)
+  }
+  return client
+}
+
+const HEARTBEAT_TIMEOUT = 2000
+function singleInstanceHealthCheckBuilder(client) {
+  const healthCheck = (callback) => _checkClient(client, callback)
+  return healthCheck
+}
+
+function clusterHealthCheckBuilder(client) {
+  return singleInstanceHealthCheckBuilder(client)
+}
+
+function _checkClient(client, callback) {
+  callback = _.once(callback)
+  // check the redis connection by storing and retrieving a unique key/value pair
+  const uniqueToken = `host=${HOST}:pid=${PID}:random=${RND}:time=${Date.now()}:count=${COUNT++}`
+  const timer = setTimeout(function () {
+    const error = new Error(
+      `redis client health check timed out ${__guard__(
+        client != null ? client.options : undefined,
+        (x) => x.host
+      )}`
+    )
+    console.error(
+      {
+        err: error,
+        key: client.options != null ? client.options.key : undefined, // only present for cluster
+        clientOptions: client.options,
+        uniqueToken,
+      },
+      'client timed out'
+    )
+    return callback(error)
+  }, HEARTBEAT_TIMEOUT)
+  const healthCheckKey = `_redis-wrapper:healthCheckKey:{${uniqueToken}}`
+  const healthCheckValue = `_redis-wrapper:healthCheckValue:{${uniqueToken}}`
+  // set the unique key/value pair
+  let multi = client.multi()
+  multi.set(healthCheckKey, healthCheckValue, 'EX', 60)
+  return multi.exec(function (err, reply) {
+    if (err != null) {
+      clearTimeout(timer)
+      return callback(err)
     }
-    if (opts.retry_max_delay == null) {
-      opts.retry_max_delay = 5000 // ms
-    }
-
-    if (opts.cluster != null) {
-      const Redis = require('ioredis')
-      standardOpts = _.clone(opts)
-      delete standardOpts.cluster
-      delete standardOpts.key_schema
-      client = new Redis.Cluster(opts.cluster, standardOpts)
-      client.healthCheck = RedisSharelatex.clusterHealthCheckBuilder(client)
-      RedisSharelatex._monkeyPatchIoredisExec(client)
-    } else {
-      standardOpts = _.clone(opts)
-      const ioredis = require('ioredis')
-      client = new ioredis(standardOpts)
-      RedisSharelatex._monkeyPatchIoredisExec(client)
-      client.healthCheck = RedisSharelatex.singleInstanceHealthCheckBuilder(
-        client
-      )
-    }
-    return client
-  },
-
-  HEARTBEAT_TIMEOUT: 2000,
-  singleInstanceHealthCheckBuilder(client) {
-    const healthCheck = (callback) =>
-      RedisSharelatex._checkClient(client, callback)
-    return healthCheck
-  },
-
-  clusterHealthCheckBuilder(client) {
-    return RedisSharelatex.singleInstanceHealthCheckBuilder(client)
-  },
-
-  _checkClient(client, callback) {
-    callback = _.once(callback)
-    // check the redis connection by storing and retrieving a unique key/value pair
-    const uniqueToken = `host=${HOST}:pid=${PID}:random=${RND}:time=${Date.now()}:count=${COUNT++}`
-    const timer = setTimeout(function () {
-      const error = new Error(
-        `redis client health check timed out ${__guard__(
-          client != null ? client.options : undefined,
-          (x) => x.host
-        )}`
-      )
-      console.error(
-        {
-          err: error,
-          key: client.options != null ? client.options.key : undefined, // only present for cluster
-          clientOptions: client.options,
-          uniqueToken,
-        },
-        'client timed out'
-      )
-      return callback(error)
-    }, RedisSharelatex.HEARTBEAT_TIMEOUT)
-    const healthCheckKey = `_redis-wrapper:healthCheckKey:{${uniqueToken}}`
-    const healthCheckValue = `_redis-wrapper:healthCheckValue:{${uniqueToken}}`
-    // set the unique key/value pair
-    let multi = client.multi()
-    multi.set(healthCheckKey, healthCheckValue, 'EX', 60)
+    // check that we can retrieve the unique key/value pair
+    multi = client.multi()
+    multi.get(healthCheckKey)
+    multi.del(healthCheckKey)
     return multi.exec(function (err, reply) {
+      clearTimeout(timer)
       if (err != null) {
-        clearTimeout(timer)
         return callback(err)
       }
-      // check that we can retrieve the unique key/value pair
-      multi = client.multi()
-      multi.get(healthCheckKey)
-      multi.del(healthCheckKey)
-      return multi.exec(function (err, reply) {
-        clearTimeout(timer)
-        if (err != null) {
-          return callback(err)
-        }
-        if (
-          (reply != null ? reply[0] : undefined) !== healthCheckValue ||
-          (reply != null ? reply[1] : undefined) !== 1
-        ) {
-          return callback(new Error('bad response from redis health check'))
-        }
-        return callback()
-      })
-    })
-  },
-
-  _monkeyPatchIoredisExec(client) {
-    const _multi = client.multi
-    return (client.multi = function (...args) {
-      const multi = _multi.call(client, ...Array.from(args))
-      const _exec = multi.exec
-      multi.exec = function (callback) {
-        if (callback == null) {
-          callback = function () {}
-        }
-        return _exec.call(multi, function (error, result) {
-          // ioredis exec returns an results like:
-          // [ [null, 42], [null, "foo"] ]
-          // where the first entries in each 2-tuple are
-          // presumably errors for each individual command,
-          // and the second entry is the result. We need to transform
-          // this into the same result as the old redis driver:
-          // [ 42, "foo" ]
-          const filtered_result = []
-          for (const entry of Array.from(result || [])) {
-            if (entry[0] != null) {
-              return callback(entry[0])
-            } else {
-              filtered_result.push(entry[1])
-            }
-          }
-          return callback(error, filtered_result)
-        })
+      if (
+        (reply != null ? reply[0] : undefined) !== healthCheckValue ||
+        (reply != null ? reply[1] : undefined) !== 1
+      ) {
+        return callback(new Error('bad response from redis health check'))
       }
-      return multi
+      return callback()
     })
-  },
+  })
+}
+
+function _monkeyPatchIoredisExec(client) {
+  const _multi = client.multi
+  return (client.multi = function (...args) {
+    const multi = _multi.call(client, ...Array.from(args))
+    const _exec = multi.exec
+    multi.exec = function (callback) {
+      if (callback == null) {
+        callback = function () {}
+      }
+      return _exec.call(multi, function (error, result) {
+        // ioredis exec returns an results like:
+        // [ [null, 42], [null, "foo"] ]
+        // where the first entries in each 2-tuple are
+        // presumably errors for each individual command,
+        // and the second entry is the result. We need to transform
+        // this into the same result as the old redis driver:
+        // [ 42, "foo" ]
+        const filtered_result = []
+        for (const entry of Array.from(result || [])) {
+          if (entry[0] != null) {
+            return callback(entry[0])
+          } else {
+            filtered_result.push(entry[1])
+          }
+        }
+        return callback(error, filtered_result)
+      })
+    }
+    return multi
+  })
 }
 
 function __guard__(value, transform) {
@@ -148,3 +142,7 @@ function __guard__(value, transform) {
     ? transform(value)
     : undefined
 }
+
+module.exports = {
+  createClient,
+}

libraries/redis-wrapper/test/unit/src/test.js

@@ -126,7 +126,8 @@ describe('index', function () {
       this.results = []
       this.multiOrig = { exec: sinon.stub().yields(null, this.results) }
       this.client = { multi: sinon.stub().returns(this.multiOrig) }
-      this.redis._monkeyPatchIoredisExec(this.client)
+      this.ioredisConstructor.returns(this.client)
+      this.redis.createClient(this.client)
       return (this.multi = this.client.multi())
     })