Fortio

Fortio (Φορτίο) started as, and is, Istio's load testing tool and now graduated to be its own project.

Fortio runs at a specified query per second (qps) and records an histogram of execution time and calculates percentiles (e.g. p99 ie the response time such as 99% of the requests take less than that number (in seconds, SI unit)). It can run for a set duration, for a fixed number of calls, or until interrupted (at a constant target QPS, or max speed/load per connection/thread).

The name fortio comes from greek φορτίο which means load/burden.

Fortio is a fast, small (3Mb docker image, minimal dependencies), reusable, embeddable go library as well as a command line tool and server process, the server includes a simple web UI and graphical representation of the results (both a single latency graph and a multiple results comparative min, max, avg, qps and percentiles graphs).

Fortio also includes a set of server side features (similar to httpbin) to help debugging and testing: request echo back including headers, adding latency or error codes with a probability distribution, tcp proxying, GRPC echo/health in addition to http, etc...

Fortio is quite mature and very stable with no known major bugs (lots of possible improvements if you want to contribute though!), and when bugs are found they are fixed quickly, so after 1 year of development and 42 incremental releases, we reached 1.0 in June 2018.

Installation

go get fortio.org/fortiofortio

Or use docker, for instance:

docker run -p 8080:8080 -p 8079:8079 fortio/fortio server & # For the server
docker run fortio/fortio load http://www.google.com/ # For a test run

Or download one the binary distributions, from the releases assets page or for instance:

curl -L https://github.com/fortio/fortio/releases/download/v1.3.0/fortio-linux_x64-1.3.0.tgz \
 | sudo tar -C / -xvzpf -
# or the debian package
wget https://github.com/fortio/fortio/releases/download/v1.3.0/fortio_1.3.0-1_amd64.deb
dpkg -i fortio_1.3.0-1_amd64.deb
# or the rpm
rpm -i https://github.com/fortio/fortio/releases/download/v1.3.0/fortio-1.3.0-1.x86_64.rpm

On a MacOS you can also install Fortio using Homebrew:

brew install fortio
fortio server

You can get a preview of the reporting/graphing UI at https://fortio.istio.io/ and on istio.io/docs/performance-and-scalability/synthetic-benchmarks/

Command line arguments

loadservergrpcpingcurl-curlredirectreportversionfortio version -shelp

Most important flags for http load generation:

-qps rate-c connections-t duration-t 30min-n numcalls-r resolution-H "header: value"-a-json filename--data-dirfortio report-a-labels "l1 l2 ..."
-content-type-payload-*
fortio help
Φορτίο 1.3.0 usage:
        fortio command [flags] target
where command is one of: load (load testing), server (starts grpc ping and
http echo/ui/redirect/proxy servers), grpcping (grpc client), report (report
only UI server), redirect (redirect only server), or curl (single URL debug).
where target is a url (http load tests) or host:port (grpc health test).
flags are:
  -H header
        Additional header(s)
  -L    Follow redirects (implies -std-client) - do not use for load test
  -P value
        Proxies to run, e.g -P "localport1 dest_host1:dest_port1" -P "[::1]:0
www.google.com:443" ...
  -a    Automatically save JSON result with filename based on labels & timestamp
  -abort-on int
        Http code that if encountered aborts the run. e.g. 503 or -1 for socket
errors.
  -allow-initial-errors
        Allow and don't abort on initial warmup errors
  -base-url string
        base URL used as prefix for data/index.tsv generation. (when empty, the
url from the first request is used)
  -c int
        Number of connections/goroutine/threads (default 4)
  -cacert Path
        Path to a custom CA certificate file to be used for the GRPC client
TLS, if empty, use https:// prefix for standard internet CAs TLS
  -cert Path
        Path to the certificate file to be used for GRPC server TLS
  -compression
        Enable http compression
  -content-type string
        Sets http content type. Setting this value switches the request method
from GET to POST.
  -curl
        Just fetch the content once
  -data-dir Directory
        Directory where JSON results are stored/read (default ".")
  -echo-debug-path string
        http echo server URI for debug, empty turns off that part (more secure)
(default "/debug")
  -gomaxprocs int
        Setting for runtime.GOMAXPROCS, <1 doesn't change the default
  -grpc
        Use GRPC (health check by default, add -ping for ping) for load testing
  -grpc-max-streams uint
        MaxConcurrentStreams for the grpc server. Default (0) is to leave the
option unset.
  -grpc-ping-delay duration
        grpc ping delay in response
  -grpc-port string
        grpc server port. Can be in the form of host:port, ip:port or port or
/unix/domain/path or "disabled" to not start the grpc server. (default "8079")
  -halfclose
        When not keepalive, whether to half close the connection (only for fast
http)
  -health
        grpc ping client mode: use health instead of ping
  -healthservice string
        which service string to pass to health check
  -http-port string
        http echo server port. Can be in the form of host:port, ip:port, port
or /unix/domain/path. (default "8080")
  -http1.0
        Use http1.0 (instead of http 1.1)
  -httpbufferkb kbytes
        Size of the buffer (max data size) for the optimized http client in
kbytes (default 128)
  -httpccch
        Check for Connection: Close Header
  -https-insecure
        Long form of the -k flag
  -json path
        Json output to provided file path or '-' for stdout (empty = no json
output, unless -a is used)
  -k    Do not verify certs in https connections
  -keepalive
        Keep connection alive (only for fast http 1.1) (default true)
  -key Path
        Path to the key file used for GRPC server TLS
  -labels string
        Additional config data/labels to add to the resulting JSON, defaults to
target URL and hostname
  -logcaller
        Logs filename and line number of callers to log (default true)
  -loglevel value
        loglevel, one of [Debug Verbose Info Warning Error Critical Fatal]
(default Info)
  -logprefix string
        Prefix to log lines before logged messages (default "> ")
  -maxpayloadsizekb int
        MaxPayloadSize is the maximum size of payload to be generated by the
EchoHandler size= argument. In Kbytes. (default 256)
  -n int
        Run for exactly this number of calls instead of duration. Default (0)
is to use duration (-t). Default is 1 when used as grpc ping count.
  -p string
        List of pXX to calculate (default "50,75,90,99,99.9")
  -payload string
        Payload string to send along
  -payload-file path
        File path to be use as payload (POST for http), replaces -payload when
set.
  -payload-size int
        Additional random payload size, replaces -payload when set > 0, must be
smaller than -maxpayloadsizekb. Setting this switches http to POST.
  -ping
        grpc load test: use ping instead of health
  -profile file
        write .cpu and .mem profiles to file
  -qps float
        Queries Per Seconds or 0 for no wait/max qps (default 8)
  -quiet
        Quiet mode: sets the loglevel to Error and reduces the output.
  -r float
        Resolution of the histogram lowest buckets in seconds (default 0.001)
  -redirect-port string
        Redirect all incoming traffic to https URL (need ingress to work
properly). Can be in the form of host:port, ip:port, port or "disabled" to
disable the feature. (default "8081")
  -s int
        Number of streams per grpc connection (default 1)
  -static-dir path
        Absolute path to the dir containing the static files dir
  -stdclient
        Use the slower net/http standard client (works for TLS)
  -sync string
        index.tsv or s3/gcs bucket xml URL to fetch at startup for server modes.
  -sync-interval duration
        Refresh the url every given interval (default, no refresh)
  -t duration
        How long to run the test or 0 to run until ^C (default 5s)
  -timeout duration
        Connection and read timeout value (for http) (default 15s)
  -ui-path string
        http server URI for UI, empty turns off that part (more secure)
(default "/fortio/")
  -unix-socket path
        Unix domain socket path to use for physical connection
  -user user:password
        User credentials for basic authentication (for http). Input data format
should be user:password

See also the FAQ entry about fortio flags for best results

Example use and output

Start the internal servers

$ fortio server &
Fortio 1.3.0 grpc 'ping' server listening on [::]:8079
Fortio 1.3.0 https redirector server listening on [::]:8081
Fortio 1.3.0 echo server listening on [::]:8080
UI started - visit:
http://localhost:8080/fortio/
(or any host/ip reachable on this server)
14:57:12 I fortio_main.go:217> All fortio 1.3.0 release go1.10.3 servers started!

Change the port / binding address

-http-port
$ fortio server -http-port 10.10.10.10:8088
UI starting - visit:
http://10.10.10.10:8088/fortio/
Https redirector running on :8081
Fortio 1.3.0 grpc ping server listening on port :8079
Fortio 1.3.0 echo server listening on port 10.10.10.10:8088

Unix domain sockets

You can use unix domain socket for any server/client:

$ fortio server --http-port /tmp/fortio-uds-http &
Fortio 1.3.0 grpc 'ping' server listening on [::]:8079
Fortio 1.3.0 https redirector server listening on [::]:8081
Fortio 1.3.0 echo server listening on /tmp/fortio-uds-http
UI started - visit:
fortio curl -unix-socket=/tmp/fortio-uds-http http://localhost/fortio/
14:58:45 I fortio_main.go:217> All fortio 1.3.0 unknown go1.10.3 servers started!
$ fortio curl -unix-socket=/tmp/fortio-uds-http http://foo.bar/debug
15:00:48 I http_client.go:428> Using unix domain socket /tmp/fortio-uds-http instead of foo.bar http
HTTP/1.1 200 OK
Content-Type: text/plain; charset=UTF-8
Date: Wed, 08 Aug 2018 22:00:48 GMT
Content-Length: 231

Φορτίο version 1.3.0 unknown go1.10.3 echo debug server up for 2m3.4s on ldemailly-macbookpro - request from

GET /debug HTTP/1.1

headers:

Host: foo.bar
User-Agent: fortio.org/fortio-1.3.0

body:

GRPC

Simple grpc ping

$ fortio grpcping localhost
02:29:27 I pingsrv.go:116> Ping RTT 305334 (avg of 342970, 293515, 279517 ns) clock skew -2137
Clock skew histogram usec : count 1 avg -2.137 +/- 0 min -2.137 max -2.137 sum -2.137
# range, mid point, percentile, count
>= -4 < -2 , -3 , 100.00, 1
# target 50% -2.137
RTT histogram usec : count 3 avg 305.334 +/- 27.22 min 279.517 max 342.97 sum 916.002
# range, mid point, percentile, count
>= 250 < 300 , 275 , 66.67, 2
>= 300 < 350 , 325 , 100.00, 1
# target 50% 294.879

Change the target port for grpc

-grpc-portgrpcping:portgrpcping
$ fortio grpcping 10.10.10.100:8078 # Connects to gRPC server 10.10.10.100 listening on port 8078
02:29:27 I pingsrv.go:116> Ping RTT 305334 (avg of 342970, 293515, 279517 ns) clock skew -2137
Clock skew histogram usec : count 1 avg -2.137 +/- 0 min -2.137 max -2.137 sum -2.137
# range, mid point, percentile, count
>= -4 < -2 , -3 , 100.00, 1
# target 50% -2.137
RTT histogram usec : count 3 avg 305.334 +/- 27.22 min 279.517 max 342.97 sum 916.002
# range, mid point, percentile, count
>= 250 < 300 , 275 , 66.67, 2
>= 300 < 350 , 325 , 100.00, 1
# target 50% 294.879
grpcping
-cert-key
/path/to/fortio/server.crt/path/to/fortio/server.key
$ fortio server -cert /path/to/fortio/server.crt -key /path/to/fortio/server.key
UI starting - visit:
http://localhost:8080/fortio/
Https redirector running on :8081
Fortio 1.3.0 grpc ping server listening on port :8079
Fortio 1.3.0 echo server listening on port localhost:8080
Using server certificate /path/to/fortio/server.crt to construct TLS credentials
Using server key /path/to/fortio/server.key to construct TLS credentials
grpcping-cacert
/path/to/fortio/ca.crtlocalhost/path/to/fortio/server.crt
$ fortio grpcping -cacert /path/to/fortio/ca.crt localhost
Using server certificate /path/to/fortio/ca.crt to construct TLS credentials
16:00:10 I pingsrv.go:129> Ping RTT 501452 (avg of 595441, 537088, 371828 ns) clock skew 31094
Clock skew histogram usec : count 1 avg 31.094 +/- 0 min 31.094 max 31.094 sum 31.094
# range, mid point, percentile, count
>= 31.094 <= 31.094 , 31.094 , 100.00, 1
# target 50% 31.094
RTT histogram usec : count 3 avg 501.45233 +/- 94.7 min 371.828 max 595.441 sum 1504.357
# range, mid point, percentile, count
>= 371.828 <= 400 , 385.914 , 33.33, 1
> 500 <= 595.441 , 547.721 , 100.00, 2
# target 50% 523.86

GRPC to standard https service

grpcpinghttps://
$ fortio grpcping https://fortio.istio.io
11:07:55 I grpcrunner.go:275> stripping https scheme. grpc destination: fortio.istio.io. grpc port: 443
Clock skew histogram usec : count 1 avg 12329.795 +/- 0 min 12329.795 max 12329.795 sum 12329.795
# range, mid point, percentile, count
>= 12329.8 <= 12329.8 , 12329.8 , 100.00, 1
# target 50% 12329.8

Simple load test

Load (low default qps/threading) test:

$ fortio load http://www.google.com
Fortio 1.3.0 running at 8 queries per second, 8->8 procs, for 5s: http://www.google.com
19:10:33 I httprunner.go:84> Starting http test for http://www.google.com with 4 threads at 8.0 qps
Starting at 8 qps with 4 thread(s) [gomax 8] for 5s : 10 calls each (total 40)
19:10:39 I periodic.go:314> T002 ended after 5.056753279s : 10 calls. qps=1.9775534712220633
19:10:39 I periodic.go:314> T001 ended after 5.058085991s : 10 calls. qps=1.9770324224999916
19:10:39 I periodic.go:314> T000 ended after 5.058796046s : 10 calls. qps=1.9767549252963101
19:10:39 I periodic.go:314> T003 ended after 5.059557593s : 10 calls. qps=1.9764573910247019
Ended after 5.059691387s : 40 calls. qps=7.9056
Sleep times : count 36 avg 0.49175757 +/- 0.007217 min 0.463508712 max 0.502087879 sum 17.7032725
Aggregated Function Time : count 40 avg 0.060587641 +/- 0.006564 min 0.052549016 max 0.089893269 sum 2.42350566
# range, mid point, percentile, count
>= 0.052549 < 0.06 , 0.0562745 , 47.50, 19
>= 0.06 < 0.07 , 0.065 , 92.50, 18
>= 0.07 < 0.08 , 0.075 , 97.50, 2
>= 0.08 <= 0.0898933 , 0.0849466 , 100.00, 1
# target 50% 0.0605556
# target 75% 0.0661111
# target 99% 0.085936
# target 99.9% 0.0894975
Code 200 : 40
Response Header Sizes : count 40 avg 690.475 +/- 15.77 min 592 max 693 sum 27619
Response Body/Total Sizes : count 40 avg 12565.2 +/- 301.9 min 12319 max 13665 sum 502608
All done 40 calls (plus 4 warmup) 60.588 ms avg, 7.9 qps

GRPC load test

-s-c
$ fortio load -a -grpc -ping -grpc-ping-delay 0.25s -payload "01234567890" -c 2 -s 4 https://fortio-stage.istio.io
Fortio 1.3.0 running at 8 queries per second, 8->8 procs, for 5s: https://fortio-stage.istio.io
16:32:56 I grpcrunner.go:139> Starting GRPC Ping Delay=250ms PayloadLength=11 test for https://fortio-stage.istio.io with 4*2 threads at 8.0 qps
16:32:56 I grpcrunner.go:261> stripping https scheme. grpc destination: fortio-stage.istio.io. grpc port: 443
16:32:57 I grpcrunner.go:261> stripping https scheme. grpc destination: fortio-stage.istio.io. grpc port: 443
Starting at 8 qps with 8 thread(s) [gomax 8] for 5s : 5 calls each (total 40)
16:33:04 I periodic.go:533> T005 ended after 5.283227589s : 5 calls. qps=0.9463911814835126
[...]
Ended after 5.28514474s : 40 calls. qps=7.5684
Sleep times : count 32 avg 0.97034752 +/- 0.002338 min 0.967323561 max 0.974838789 sum 31.0511206
Aggregated Function Time : count 40 avg 0.27731944 +/- 0.001606 min 0.2741372 max 0.280604967 sum 11.0927778
# range, mid point, percentile, count
>= 0.274137 <= 0.280605 , 0.277371 , 100.00, 40
# target 50% 0.277288
# target 75% 0.278947
# target 90% 0.279942
# target 99% 0.280539
# target 99.9% 0.280598
Ping SERVING : 40
All done 40 calls (plus 2 warmup) 277.319 ms avg, 7.6 qps
Successfully wrote 1210 bytes of Json data to 2018-04-03-163258_fortio_stage_istio_io_ldemailly_macbookpro.json

And the JSON saved is

{
  "RunType": "GRPC Ping Delay=250ms PayloadLength=11",
  "Labels": "fortio-stage.istio.io , ldemailly-macbookpro",
  "StartTime": "2018-04-03T16:32:58.895472681-07:00",
  "RequestedQPS": "8",
  "RequestedDuration": "5s",
  "ActualQPS": 7.568383075162479,
  "ActualDuration": 5285144740,
  "NumThreads": 8,
  "Version": "0.9.0",
  "DurationHistogram": {
    "Count": 40,
    "Min": 0.2741372,
    "Max": 0.280604967,
    "Sum": 11.092777797,
    "Avg": 0.277319444925,
    "StdDev": 0.0016060870789948905,
    "Data": [
      {
        "Start": 0.2741372,
        "End": 0.280604967,
        "Percent": 100,
        "Count": 40
      }
    ],
    "Percentiles": [
      {
        "Percentile": 50,
        "Value": 0.2772881634102564
      },
      {
        "Percentile": 75,
        "Value": 0.27894656520512817
      },
      {
        "Percentile": 90,
        "Value": 0.2799416062820513
      },
      {
        "Percentile": 99,
        "Value": 0.28053863092820513
      },
      {
        "Percentile": 99.9,
        "Value": 0.2805983333928205
      }
    ]
  },
  "Exactly": 0,
  "RetCodes": {
    "1": 40
  },
  "Destination": "https://fortio-stage.istio.io",
  "Streams": 4,
  "Ping": true
}

-cert-key
fortio server -cert /etc/ssl/certs/server.crt -key /etc/ssl/certs/server.key
load-cacert
fortio load -cacert /etc/ssl/certs/ca.crt -grpc localhost:8079

Curl like (single request) mode

$ fortio load -curl -H Foo:Bar http://localhost:8080/debug
14:26:26 I http.go:133> Setting regular extra header Foo: Bar
HTTP/1.1 200 OK
Content-Type: text/plain; charset=UTF-8
Date: Mon, 08 Jan 2018 22:26:26 GMT
Content-Length: 230

Φορτίο version 1.3.0 echo debug server up for 39s on ldemailly-macbookpro - request from [::1]:65055

GET /debug HTTP/1.1

headers:

Host: localhost:8080
User-Agent: fortio.org/fortio-1.3.0
Foo: Bar

body:

Report only UI

If you have json files saved from running the full UI, you can serve just the reports:

$ fortio report
Browse only UI starting - visit:
http://localhost:8080/
Https redirector running on :8081

Server URLs and features

server
curl -d abcdef http://localhost:8080/abcdef
delay=150us:10,2ms:5,0.5s:1status=404:10,503:5,429:1size=1024:10,512:5close=true&header=Foo:Bar&header=X:Y
/debug/fortio//fortio/data/index.tsvindex.tsv
report/

There is also the GRPC health and ping servers, as well as the http->https redirector.

Implementation details

Fortio is written in the Go language and includes a scalable semi log histogram in stats.go and a periodic runner engine in periodic.go with specializations for http and grpc. The http/ package includes a very high performance specialized http 1.1 client. You may find fortio's logger useful as well.

fortio server
fortio curl

More examples

You can get the data on the console, for instance, with 5k qps: (includes envoy and mixer in the calls)

$ time fortio load -qps 5000 -t 60s -c 8 -r 0.0001 -H "Host: perf-cluster" http://benchmark-2:9090/echo
2017/07/09 02:31:05 Will be setting special Host header to perf-cluster
Fortio running at 5000 queries per second for 1m0s: http://benchmark-2:9090/echo
Starting at 5000 qps with 8 thread(s) [gomax 4] for 1m0s : 37500 calls each (total 300000)
2017/07/09 02:32:05 T004 ended after 1m0.000907812s : 37500 calls. qps=624.9905437680746
2017/07/09 02:32:05 T000 ended after 1m0.000922222s : 37500 calls. qps=624.9903936684861
2017/07/09 02:32:05 T005 ended after 1m0.00094454s : 37500 calls. qps=624.9901611965524
2017/07/09 02:32:05 T006 ended after 1m0.000944816s : 37500 calls. qps=624.9901583216429
2017/07/09 02:32:05 T001 ended after 1m0.00102094s : 37500 calls. qps=624.9893653892883
2017/07/09 02:32:05 T007 ended after 1m0.001096292s : 37500 calls. qps=624.9885805003184
2017/07/09 02:32:05 T003 ended after 1m0.001045342s : 37500 calls. qps=624.9891112105419
2017/07/09 02:32:05 T002 ended after 1m0.001044416s : 37500 calls. qps=624.9891208560392
Ended after 1m0.00112695s : 300000 calls. qps=4999.9
Aggregated Sleep Time : count 299992 avg 8.8889218e-05 +/- 0.002326 min -0.03490402 max 0.001006041 sum 26.6660543
# range, mid point, percentile, count
< 0 , 0 , 8.58, 25726
>= 0 < 0.001 , 0.0005 , 100.00, 274265
>= 0.001 < 0.002 , 0.0015 , 100.00, 1
# target 50% 0.000453102
WARNING 8.58% of sleep were falling behind
Aggregated Function Time : count 300000 avg 0.00094608764 +/- 0.0007901 min 0.000510522 max 0.029267604 sum 283.826292
# range, mid point, percentile, count
>= 0.0005 < 0.0006 , 0.00055 , 0.15, 456
>= 0.0006 < 0.0007 , 0.00065 , 3.25, 9295
>= 0.0007 < 0.0008 , 0.00075 , 24.23, 62926
>= 0.0008 < 0.0009 , 0.00085 , 62.73, 115519
>= 0.0009 < 0.001 , 0.00095 , 85.68, 68854
>= 0.001 < 0.0011 , 0.00105 , 93.11, 22293
>= 0.0011 < 0.0012 , 0.00115 , 95.38, 6792
>= 0.0012 < 0.0014 , 0.0013 , 97.18, 5404
>= 0.0014 < 0.0016 , 0.0015 , 97.94, 2275
>= 0.0016 < 0.0018 , 0.0017 , 98.34, 1198
>= 0.0018 < 0.002 , 0.0019 , 98.60, 775
>= 0.002 < 0.0025 , 0.00225 , 98.98, 1161
>= 0.0025 < 0.003 , 0.00275 , 99.21, 671
>= 0.003 < 0.0035 , 0.00325 , 99.36, 449
>= 0.0035 < 0.004 , 0.00375 , 99.47, 351
>= 0.004 < 0.0045 , 0.00425 , 99.57, 290
>= 0.0045 < 0.005 , 0.00475 , 99.66, 280
>= 0.005 < 0.006 , 0.0055 , 99.79, 380
>= 0.006 < 0.007 , 0.0065 , 99.82, 92
>= 0.007 < 0.008 , 0.0075 , 99.83, 15
>= 0.008 < 0.009 , 0.0085 , 99.83, 5
>= 0.009 < 0.01 , 0.0095 , 99.83, 1
>= 0.01 < 0.012 , 0.011 , 99.83, 8
>= 0.012 < 0.014 , 0.013 , 99.84, 35
>= 0.014 < 0.016 , 0.015 , 99.92, 231
>= 0.016 < 0.018 , 0.017 , 99.94, 65
>= 0.018 < 0.02 , 0.019 , 99.95, 26
>= 0.02 < 0.025 , 0.0225 , 100.00, 139
>= 0.025 < 0.03 , 0.0275 , 100.00, 14
# target 50% 0.000866935
# target 75% 0.000953452
# target 99% 0.00253875
# target 99.9% 0.0155152
Code 200 : 300000
Response Body Sizes : count 300000 avg 0 +/- 0 min 0 max 0 sum 0

-json result.json

Web/Graphical UI

Or graphically (through the http://localhost:8080/fortio/ web UI):

Simple form/UI:

Sample requests with responses delayed by 250us and 0.5% of 503 and 1.5% of 429 simulated http errors.

Run result:

Code 200 : 2929 (97.6 %)
Code 429 : 56 (1.9 %)
Code 503 : 15 (0.5 %)

Contributing

Contributions whether through issues, documentation, bug fixes, or new features are most welcome !

Please also see Contributing to Istio and Getting started contributing to Fortio in the FAQ.

make pull

And make sure to go format and run those commands successfully before sending your PRs:

make test
make lint
make release-test

When modifying Javascript, check with standard:

standard --fix ui/static/js/fortio_chart.js

See also

fortiowrkhttpbin

Disclaimer

This is not an officially supported Google product.