From 4495c8f8e8ccd521ed0886e93003f28919538d7e Mon Sep 17 00:00:00 2001 From: sqshq Date: Thu, 30 May 2019 23:01:43 -0400 Subject: [PATCH] interactive shell improvements - support case when script exec time > sampling rate - extended example config file --- data/item.go | 108 +++++++++++++++++++++++----------- data/sampler.go | 4 +- example-interactive-shell.yml | 17 +++--- 3 files changed, 86 insertions(+), 43 deletions(-) diff --git a/data/item.go b/data/item.go index e697d09..07ab889 100644 --- a/data/item.go +++ b/data/item.go @@ -14,16 +14,22 @@ import ( "time" ) -const interactiveShellStartupTimeout = 100 * time.Millisecond +const ( + interactiveShellStartupTimeout = 100 * time.Millisecond + interactiveShellMinAwaitTimeout = 100 * time.Millisecond + interactiveShellMaxAwaitTimeout = 1 * time.Second + interactiveShellErrorThreshold = 10 +) type Item struct { - Label string - SampleScript string - InitScript *string - TransformScript *string - Color *ui.Color - RateMs int - InteractiveShell *InteractiveShell + label string + sampleScript string + initScript *string + transformScript *string + color *ui.Color + rateMs int + errorsCount int + interactiveShell *InteractiveShell } type InteractiveShell struct { @@ -38,12 +44,12 @@ func NewItems(cfgs []config.Item, rateMs int) []*Item { for _, i := range cfgs { item := &Item{ - Label: *i.Label, - SampleScript: *i.SampleScript, - InitScript: i.InitScript, - TransformScript: i.TransformScript, - Color: i.Color, - RateMs: rateMs, + label: *i.Label, + sampleScript: *i.SampleScript, + initScript: i.InitScript, + transformScript: i.TransformScript, + color: i.Color, + rateMs: rateMs, } items = append(items, item) } @@ -53,17 +59,17 @@ func NewItems(cfgs []config.Item, rateMs int) []*Item { func (i *Item) nextValue(variables []string) (string, error) { - if i.InitScript != nil && i.InteractiveShell == nil { + if i.initScript != nil && i.interactiveShell == nil { err := i.initInteractiveShell(variables) if err != nil { return "", errors.New(fmt.Sprintf("Failed to init interactive shell: %s", err)) } } - if i.InitScript != nil { + if i.initScript != nil { return i.executeInteractiveShellCmd(variables) } else { - return i.executeCmd(variables, i.SampleScript) + return i.executeCmd(variables, i.sampleScript) } } @@ -83,7 +89,7 @@ func (i *Item) executeCmd(variables []string, script string) (string, error) { func (i *Item) initInteractiveShell(variables []string) error { - cmd := exec.Command("sh", "-c", *i.InitScript) + cmd := exec.Command("sh", "-c", *i.initScript) enrichEnvVariables(cmd, variables) file, err := pty.Start(cmd) @@ -100,7 +106,7 @@ func (i *Item) initInteractiveShell(variables []string) error { } }() - i.InteractiveShell = &InteractiveShell{ + i.interactiveShell = &InteractiveShell{ Channel: channel, File: file, Cmd: cmd, @@ -118,43 +124,79 @@ func (i *Item) initInteractiveShell(variables []string) error { func (i *Item) executeInteractiveShellCmd(variables []string) (string, error) { - _, err := io.WriteString(i.InteractiveShell.File, fmt.Sprintf(" %s\n", i.SampleScript)) + _, err := io.WriteString(i.interactiveShell.File, fmt.Sprintf(" %s\n", i.sampleScript)) if err != nil { + i.errorsCount++ + if i.errorsCount > interactiveShellErrorThreshold { + i.interactiveShell = nil // restart session + i.errorsCount = 0 + } return "", errors.New(fmt.Sprintf("Failed to execute interactive shell cmd: %s", err)) } - timeout := make(chan bool, 1) + softTimeout := make(chan bool, 1) + hardTimeout := make(chan bool, 1) go func() { - time.Sleep(time.Duration(i.RateMs)) - timeout <- true + time.Sleep(i.getAwaitTimeout() / 4) + softTimeout <- true + time.Sleep(i.getAwaitTimeout() * 100) + hardTimeout <- true }() - var outputText strings.Builder + var builder strings.Builder + softTimeoutElapsed := false +await: for { select { - case output := <-i.InteractiveShell.Channel: - if !strings.Contains(output, i.SampleScript) && len(output) > 0 { - outputText.WriteString(output) - outputText.WriteString("\n") + case output := <-i.interactiveShell.Channel: + o := cleanupOutput(output) + if len(o) > 0 && !strings.Contains(o, i.sampleScript) { + builder.WriteString(o) + builder.WriteString("\n") + if softTimeoutElapsed { + break await + } } - case <-timeout: - sample := cleanupOutput(outputText.String()) - return i.transformInteractiveShellCmd(sample) + case <-softTimeout: + if builder.Len() > 0 { + break await + } else { + softTimeoutElapsed = true + } + case <-hardTimeout: + break await } } + + sample := strings.TrimSpace(builder.String()) + + return i.transformInteractiveShellCmd(sample) } func (i *Item) transformInteractiveShellCmd(sample string) (string, error) { - if i.TransformScript != nil && len(sample) > 0 { - return i.executeCmd([]string{"sample=" + sample}, *i.TransformScript) + if i.transformScript != nil && len(sample) > 0 { + return i.executeCmd([]string{"sample=" + sample}, *i.transformScript) } return sample, nil } +func (i *Item) getAwaitTimeout() time.Duration { + + timeout := time.Duration(i.rateMs) * time.Millisecond + + if timeout > interactiveShellMaxAwaitTimeout { + return interactiveShellMaxAwaitTimeout + } else if timeout < interactiveShellMinAwaitTimeout { + return interactiveShellMinAwaitTimeout + } + + return timeout +} + func enrichEnvVariables(cmd *exec.Cmd, variables []string) { cmd.Env = os.Environ() for _, variable := range variables { diff --git a/data/sampler.go b/data/sampler.go index b0b0d48..a919d04 100644 --- a/data/sampler.go +++ b/data/sampler.go @@ -53,14 +53,14 @@ func (s *Sampler) sample(item *Item, options config.Options) { val, err := item.nextValue(s.variables) if len(val) > 0 { - sample := &Sample{Label: item.Label, Value: val, Color: item.Color} + sample := &Sample{Label: item.label, Value: val, Color: item.color} s.consumer.SampleChannel <- sample s.triggersChannel <- sample } else if err != nil { s.consumer.AlertChannel <- &Alert{ Title: "SAMPLING FAILURE", Text: getErrorMessage(err), - Color: item.Color, + Color: item.color, } } } diff --git a/example-interactive-shell.yml b/example-interactive-shell.yml index 7b34d61..cc7fe3a 100644 --- a/example-interactive-shell.yml +++ b/example-interactive-shell.yml @@ -7,23 +7,24 @@ variables: sshconnection: ssh -i ~/sqshq.pem ec2-user@3.215.108.82 textboxes: - title: Neo4j - position: [[0, 0], [13, 40]] + position: [[0, 0], [10, 40]] init: $neo4jconnection - sample: match (n) return count(n); + sample: RETURN rand(); transform: echo "$sample" | tail -n 1 - title: Postgres - position: [[13, 0], [14, 40]] + position: [[10, 0], [9, 40]] init: $postgresconnection sample: select random(); - title: MySQL - position: [[27, 0], [14, 40]] + position: [[19, 0], [10, 40]] init: $mysqlconnection sample: select rand(); - title: MongoDB - position: [[41, 0], [13, 40]] + position: [[29, 0], [10, 40]] + rate-ms: 500 init: $mongoconnection - sample: db.getCollection('posts').find({status:'ACTIVE'}).itcount() + sample: sleep(3000);Date.now(); - title: SSH - position: [[54, 0], [13, 40]] + position: [[39, 0], [41, 40]] init: $sshconnection - sample: ps -A -o %cpu | awk '{s+=$1} END {print s}' + sample: top