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MXS-1300: Use native promises for requests

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The request-promise-native package adds support for request with native
promises. This is a convenient way to synchronize multiple HTTP requests.

The functions are changed to use promises to make testing easier. With
promises, the testing code can use the chai-as-promised library.

There are a few cases where doRequest is called with a callback that again
calls doAsyncRequest. With multiple hosts, this causes each command to be
propagated to all servers. This is a design flaw of the current multi-host
mode and needs to be changed.

Changed maxctrl.js to wait on the promises to silence some warnings if the
promise rejections are ignored.
This commit is contained in:
Markus Mäkelä
2017-07-14 05:22:34 +03:00
parent b54e94ce95
commit ec5b0fea39
9 changed files with 79 additions and 80 deletions
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112
maxctrl/common.js
View File

@ -11,7 +11,7 @@
* Public License.
*/
var request = require('request');
var request = require('request-promise-native');
var colors = require('colors/safe');
var Table = require('cli-table');
@ -127,46 +127,63 @@ module.exports = function() {
return base + argv.user + ':' + argv.password + '@' + host + '/v1/' + endpoint
}
// Helper for executing requests and handling their responses
this.doRequest = function(resource, cb, obj) {
pingCluster(this.argv.hosts)
.then(function() {
var argv = this.argv
argv.hosts.forEach(function(host) {
args = obj || {}
args.uri = getUri(host, argv.secure, resource)
args.json = true
args.timeout = argv.timeout
// Helper for executing requests and handling their responses, returns a
// promise that is fulfilled when all requests successfully complete. The
// promise is rejected if any of the requests fails.
this.doAsyncRequest = function(resource, cb, obj) {
return new Promise(function (resolve, reject) {
pingCluster(this.argv.hosts)
.then(function() {
request(args, function(err, resp, res) {
if (err) {
// Failed to request
console.log(colors.yellow(host) + ':')
logError(JSON.stringify(err, null, 4))
} else if (resp.statusCode == 200 && cb) {
// Request OK, returns data
if (!argv.tsv) {
var promises = []
this.argv.hosts.forEach(function(host) {
args = obj || {}
args.uri = getUri(host, this.argv.secure, resource)
args.json = true
args.timeout = this.argv.timeout
var p = request(args)
.then(function(res) {
if (res && cb) {
// Request OK, returns data
if (!this.argv.tsv) {
console.log(colors.yellow(host) + ':')
}
return cb(res)
} else {
// Request OK, no data or data is ignored
console.log(colors.yellow(host) + ': ' + colors.green('OK'))
}
return Promise.resolve()
}, function(err) {
console.log(colors.yellow(host) + ':')
}
cb(res)
} else if (resp.statusCode == 204) {
// Request OK, no data
console.log(colors.yellow(host) + ': ' + colors.green('OK'))
} else {
// Unexpected return code, probably an error
var errstr = resp.statusCode + ' ' + resp.statusMessage
if (res) {
errstr += ' ' + JSON.stringify(res, null, 4)
}
console.log(colors.yellow(host) + ':')
logError(errstr)
}
if (err.response.body) {
logError(JSON.stringify(err.response.body, null, 4))
} else {
logError('Server responded with ' + err.statusCode)
}
return Promise.reject()
})
// Push the request on to the stack
promises.push(p)
})
// Wait for all promises to resolve or reject
Promise.all(promises)
.then(resolve, reject)
}, function(err) {
// One of the HTTP request pings to the cluster failed, log the error
logError(JSON.stringify(err.error, null, 4))
reject()
})
})
.catch(function(err) {
logError(JSON.stringify(err, null, 4))
})
})
}
this.doRequest = function(resource, cb, obj) {
return doAsyncRequest(resource, cb, obj)
.then(this.argv.resolve, this.argv.reject)
}
this.updateValue = function(resource, key, value) {
@ -178,6 +195,11 @@ module.exports = function() {
this.logError = function(err) {
console.log(colors.red('Error:'), err)
}
this.error = function(err) {
console.log(colors.red('Error:'), err)
this.argv.reject()
}
}
var tsvopts = {
@ -230,25 +252,11 @@ function getTable(headobj) {
return new Table(opts)
}
function pingMaxScale(host) {
return new Promise(function(resolve, reject) {
request('http://' + host + '/v1', function(err, resp, res) {
if (err) {
reject(err)
} else if (resp.statusCode != 200) {
reject(resp.statusCode + ' ' + resp.statusMessage)
} else {
resolve()
}
})
})
}
function pingCluster(hosts) {
var promises = []
hosts.forEach(function(i) {
promises.push(pingMaxScale(i))
promises.push(request('http://' + i + '/v1'))
})
return Promise.all(promises)