Just output the ttfb value for the basic option

-v option shows response breakdown for single and multiple requests Also tidied README
2025-12-10 07:57:21 +01:00 · 2019-04-11 21:28:20 +01:00
parent 392c669092
commit a2357a6035
2 changed files with 128 additions and 50 deletions
--- a/README.md
+++ b/README.md
@@ -1,15 +1,24 @@
 # Introduction

-Measures [time-to-first-byte](https://en.wikipedia.org/wiki/Time_to_first_byte) for single or multiple URLs. Can calculate min, max & median TTFB values and log all response headers.
+Measures [time-to-first-byte](https://en.wikipedia.org/wiki/Time_to_first_byte) for single or multiple URLs. Can show you quickest, slowest & median TTFB values plus optionally log all response headers.

 ```
 Usage: ttfb [options] url [url...]
 	-d debug
-  -l <log file> (infers -d)
-  -n number of times to test
+	-l <log file> (infers -d) log response headers. Defaults to ./curl.log
+	-n <number> of times to test time to first byte
+	-v verbose output. Show response breakdown (DNS lookup, TLS handshake etc)
 ```

-Uses the calculation `%{time_starttransfer¹} - %{time_appconnect²}` which doesn't include any connection overhead, to better approximate devtool’s TTFB figure.
+Implicitly follows a redirection chain using curl's `-L` option.
+
+Can log all response headers (the default log file is `./curl.log`) by calling with `-d`.
+
+Override the default log file by specifying `-l /some/file`.
+
+Get quickest, slowest and median TTFB values by specifying the number of times to call a URL; use `-n2` for 2 tests, `-n5` for 5 and so on.
+
+Uses the calculation `%{time_starttransfer¹} - %{time_appconnect²}` which doesn't include any connection overhead, to better approximate [devtool’s TTFB figure](https://developers.google.com/web/tools/chrome-devtools/network/understanding-resource-timing#slow_time_to_first_byte).

 ¹ [`time_starttransfer`](https://github.com/curl/curl/blob/e431daf013ea04cb1a988a2009d820224ef5fb79/docs/cmdline-opts/write-out.d#L141-L144)
 > The time, in seconds, it took from the start until the first byte was just about to be transferred. This includes time_pretransfer and also the time the server needed to calculate the result.</blockquote>
@@ -19,7 +28,7 @@ Uses the calculation `%{time_starttransfer¹} - %{time_appconnect²}` which does
 connect/handshake to the remote host was completed.

 # Genesis
-Based on a gist https://gist.github.com/sandeepraju/1f5fbdbdd89551ba7925abe2645f92b5
+Based on a [gist](https://gist.github.com/sandeepraju/1f5fbdbdd89551ba7925abe2645f92b5)
 by https://github.com/sandeepraju

 Modified by jay@gooby.org, [@jaygooby](https://twitter.com/jaygooby)
@@ -29,23 +38,45 @@ Modified by jay@gooby.org, [@jaygooby](https://twitter.com/jaygooby)
 ```
 Usage: ttfb [options] url [url...]
 	-d debug
-  -l <log file> (infers -d)
-  -n number of times to test
+	-l <log file> (infers -d) log response headers. Defaults to ./curl.log
+	-n <number> of times to test time to first byte
+	-v verbose output. Show response breakdown (DNS lookup, TLS handshake etc)
 ```

-Examples:
+## Examples
+
+Basic usage:

 ```
 $ ttfb example.com
-DNS lookup: 0.523402 TLS handshake: 0.000000 TTFB including connection: 0.692724 TTFB: .692724 Total time: 0.693508
+.227436
 ```

+Basic usage with verbose response breakdown:
+
 ```
-$ ttfb -n 5 example.com
+$ ttfb -v https://example.com
+DNS lookup: 0.005152 TLS handshake: 0.000000 TTFB including connection: 0.200831 TTFB: .200831 Total time: 0.201132
+```
+
+Test multiple times:
+
+```
+$ ttfb -n 5 example.com/example/url
 .....
 fastest .177263 slowest .214302 median .179957
 ```

+Test multiple URLs:
+
+```
+$ ttfb bbc.co.uk news.bbc.co.uk
+bbc.co.uk        .049985
+news.bbc.co.uk   .054122
+```
+
+Test multiple URLs, multiple times:
+
 ```
 $ ttfb -n 5 bbc.co.uk news.bbc.co.uk
 .....
@@ -54,33 +85,67 @@ bbc.co.uk       fastest .030936 slowest .057755 median .034663
 news.bbc.co.uk  fastest .031413 slowest .182791 median .035001
 ```

-```
-$ ttfb bbc.co.uk news.bbc.co.uk
-bbc.co.uk        DNS lookup: 0.005291 TLS handshake: 0.089403 TTFB including connection: 0.119651 TTFB: .030248 Total time: 0.506010
-news.bbc.co.uk   DNS lookup: 0.004266 TLS handshake: 0.077179 TTFB including connection: 0.110649 TTFB: .033470 Total time: 0.598472
-```
-
-Implicitly follows redirects using curl's `-L`
-
-Log all response headers (default log file is `curl.log`) by calling with `-d`
-
-Override the default log file by specifying `-l /some/file`
-
-Get min, max and median values by specifying the number of times to call
-the URL (`-n2` etc)
-
-If you specify more than one url and have specified `-d` or `-l` the log file
-will be prefixed with the URL being requested.
+Verbose response breakdown when multiple tests specified:

 ```
-$ ttfb -d bbc.co.uk news.bbc.co.uk
-bbc.co.uk        DNS lookup: 0.005309 TLS handshake: 0.074216 TTFB including connection: 0.106453 TTFB: .032237 Total time: 0.462894
-news.bbc.co.uk   DNS lookup: 0.005355 TLS handshake: 5.358041 TTFB including connection: 5.397377 TTFB: .039336 Total time: 6.013918
+$ ttfb -v -n 5 bbc.co.uk
+DNS lookup: 0.005335 TLS handshake: 0.102314 TTFB including connection: 0.148328 TTFB: .046014 Total time: 0.646115
+DNS lookup: 0.005322 TLS handshake: 0.102609 TTFB including connection: 0.150693 TTFB: .048084 Total time: 0.644611
+DNS lookup: 0.004277 TLS handshake: 0.102066 TTFB including connection: 0.172199 TTFB: .070133 Total time: 1.196256
+DNS lookup: 0.004444 TLS handshake: 0.107375 TTFB including connection: 0.160771 TTFB: .053396 Total time: 0.637290
+DNS lookup: 0.005352 TLS handshake: 0.118882 TTFB including connection: 0.168772 TTFB: .049890 Total time: 0.653761

-$ ls
-bbc_co_uk-curl.log      news_bbc_co_uk-curl.log
+fastest .046014 slowest .070133 median .049890
 ```

+Log all the response headers for multiple tests to multiple URLs:
+
+```
+ttfb -d -n 2 bbc.co.uk https://www.bbc.co.uk/weather
+..
+..
+bbc.co.uk                      fastest .027550 slowest .055215 median .041382
+https://www.bbc.co.uk/weather  fastest .101020 slowest .297923 median .199471
+
+$ ls *.log
+bbc_co_uk-curl.log                     https___www_bbc_co_uk_weather-curl.log
+
+$ cat https___www_bbc_co_uk_weather-curl.log
+HTTP/2 200
+server: openresty
+x-cache-action: MISS
+vary: Accept-Encoding,X-BBC-Edge-Cache,X-BBC-Edge-Scheme,X-CDN
+x-cache-age: 0
+cache-control: private, stale-while-revalidate=10, max-age=0, must-revalidate
+content-type: text/html;charset=utf-8
+x-mrid: w1
+date: Thu, 11 Apr 2019 17:08:07 GMT
+x-xss-protection: 1; mode=block
+x-content-type-options: nosniff
+x-lb-nocache: true
+x-msig: 24e37f81323984e4e45b8048f9e3c94a
+x-frame-options: SAMEORIGIN
+content-length: 1077454
+
+HTTP/2 200
+server: openresty
+x-cache-action: MISS
+vary: Accept-Encoding,X-BBC-Edge-Cache,X-BBC-Edge-Scheme,X-CDN
+x-cache-age: 0
+cache-control: private, stale-while-revalidate=10, max-age=0, must-revalidate
+content-type: text/html;charset=utf-8
+x-mrid: w1
+date: Thu, 11 Apr 2019 17:08:08 GMT
+x-xss-protection: 1; mode=block
+x-content-type-options: nosniff
+x-lb-nocache: true
+x-msig: 24e37f81323984e4e45b8048f9e3c94a
+x-frame-options: SAMEORIGIN
+content-length: 1077454
+```
+
+# More detail on time-to-first-byte
+
 See https://blog.cloudflare.com/a-question-of-timing/
 and https://curl.haxx.se/docs/manpage.html for an explanation
 of how the curl variables relate to the various stages of
--- a/43
+++ b/43
@@ -1,5 +1,7 @@
 #!/bin/bash
 #
+# Shows time in seconds to first byte of a url or urls
+#
 # Based on a gist https://gist.github.com/sandeepraju/1f5fbdbdd89551ba7925abe2645f92b5
 # by https://github.com/sandeepraju
 #
@@ -13,30 +15,33 @@
 #
 # Examples:
 #
-# ttfb example.com
-# DNS lookup: 0.523402 TLS handshake: 0.000000 TTFB including connection: 0.692724 TTFB: .692724 Total time: 0.693508
+# ttfb https://example.com/example/url
+# .098974
 #
-# ttfb -n 5 example.com
-# min .203970 max .181486 median .190033
+# ttfb -n 5 https://example.com/
+# .....
+# fastest .099195 slowest .103138 median .099684
 #
 # ttfb -n 5 bbc.co.uk news.bbc.co.uk
-# bbc.co.uk       min .032791 max .039401 median .029214
-# news.bbc.co.uk  min .032927 max .032237 median .037458
+# .....
+# .....
+# bbc.co.uk       fastest .045873 slowest .046870 median .045999
+# news.bbc.co.uk  fastest .042286 slowest .060245 median .046035
 #
 # ttfb bbc.co.uk news.bbc.co.uk
-# bbc.co.uk        DNS lookup: 0.005291 TLS handshake: 0.089403 TTFB including connection: 0.119651 TTFB: .030248 Total time: 0.506010
-# news.bbc.co.uk   DNS lookup: 0.004266 TLS handshake: 0.077179 TTFB including connection: 0.110649 TTFB: .033470 Total time: 0.598472
+# bbc.co.uk        .048378
+# news.bbc.co.uk   .049303
 #
-# Implicitly follows redirects using curl's -L
+# Implicitly follows redirects using curl's -L option.
 #
 # Log all response headers (default log file is ./curl.log) by calling with -d
 #
 # Override the default log file by specifying -l /some/file
 #
 # Get min, max and median values by specifying the number of times to call
-# the URL (-n2 etc)
+# the URL; use -n2 for 2 tests, -n5 for 5 and so on.
 #
-# If you specify more than one url and have specified -d or -l the log file
+# If you specify more than one url and have specified -d or -l, the log file
 # will be prefixed with the URL being requested.
 #
 # If you specify -n and -d or -l, the response headers from the consecutive
@@ -55,6 +60,11 @@
 # on bc and column commands.
 set -eu

+# check dependencies
+for dependency in curl bc column; do
+  which -s $dependency || (echo "You need to have '$dependency' installed and in your \$PATH" >&2 && exit 1)
+done
+
 # Cribbed from https://stackoverflow.com/a/41762669/391826
 median() {
  arr=($(printf '%s\n' "${@}" | sort -n))
@@ -64,7 +74,6 @@ median() {
  else                            # Even number of elements
    (( j=nel/2 ))
    (( k=j-1 ))
-    # (( val=(${arr[j]} + ${arr[k]})/2 ))
    val=$(echo "scale=6;(${arr[j]}" + "${arr[k]})"/2|bc -l)
  fi
  echo $val
@@ -83,7 +92,7 @@ do
        l) LOG="$OPTARG" ;;
        n) NUM_REQUESTS=$OPTARG ;;
        v) VERBOSE=1 ;;
-        \?) echo -e "Usage: ttfb [options] url [url...]\n\t-d debug\n\t-l <log file> (infers -d) log response headers. Defaults to curl.log\n\t-n <number> of times to test time to first byte\n\t-v verbose output. Show request breakdown during -n calls" >&2
+        \?) echo -e "Usage: ttfb [options] url [url...]\n\t-d debug\n\t-l <log file> (infers -d) log response headers. Defaults to ./curl.log\n\t-n <number> of times to test time to first byte\n\t-v verbose output. Show response breakdown (DNS lookup, TLS handshake etc)" >&2
            exit 1
            ;;
    esac
@@ -100,7 +109,7 @@ else
 fi

 # if we're given a custom log file, or log directory, implicitly set DEBUG=1
-([ -n "$LOG" ] || [ -n "$LOG_DIRECTORY" ]) && DEBUG=1
+[ -n "$LOG" ] && DEBUG=1

 # default the log file to curl.log in pwd or LOG_DIRECTORY if -o was specified
 LOG="${LOG:-curl.log}"
@@ -135,7 +144,7 @@ for URL in $URLS; do
  # output the url on the results line
  if [ ${#@} -gt 1 ]; then
    SHOW_URL="${URL}|"
-    if [ $VERBOSE -eq 1 ]; then
+    if [[ $VERBOSE -eq 1 && -n "$NUM_REQUESTS" && "$NUM_REQUESTS" -gt 1 ]]; then
      echo $URL >&2
    fi
  else
@@ -182,6 +191,10 @@ for URL in $URLS; do
    # show quickest, slowest and median fftb
    printf "${SHOW_URL}\e[32mfastest \e[39m${ttfbs[0]} \e[91mslowest \e[39m${ttfbs[${#ttfbs[*]}-1]} \e[95mmedian \e[39m$(median ${ttfbs[*]})\e[39m\n";
  else
+   if [ $VERBOSE -eq 1 ]; then
     echo -e $SHOW_URL $(eval $(curl "${options[@]}" "$URL"))
+   else
+     echo -e $SHOW_URL $(eval $(curl "${options[@]}" "$URL") | grep -oE "TTFB: .{0,7}" | cut -d' ' -f2)
+   fi
  fi
 done | column -s'|' -t