ci: Add retry

From: https://github.com/kadwanev/retry/tree/a1b1826bdb0a78189d5c70c858dc676f5133b1d7

1 files changed, 123 insertions, 0 deletions

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+retry - The command line retry tool
+------------------------------------------
+
+Retry any shell command with exponential backoff or constant delay.
+
+### Instructions
+
+Install:
+
+retry is a shell script, so drop it somewhere and make sure it's added to your $PATH. Or you can use the following one-liner:
+
+```sh
+sudo sh -c "curl https://raw.githubusercontent.com/kadwanev/retry/master/retry -o /usr/local/bin/retry && chmod +x /usr/local/bin/retry"
+```
+
+If you're on OS X, retry is also on Homebrew:
+
+```
+brew pull 27283
+brew install retry
+```
+Not popular enough for homebrew-core. Please star this project to help.
+
+### Usage
+
+Help:
+
+`retry -?`
+
+    Usage: retry [options] -- execute command
+        -h, -?, --help
+        -v, --verbose                    Verbose output
+        -t, --tries=#                    Set max retries: Default 10
+        -s, --sleep=secs                 Constant sleep amount (seconds)
+        -m, --min=secs                   Exponenetial Backoff: minimum sleep amount (seconds): Default 0.3
+        -x, --max=secs                   Exponenetial Backoff: maximum sleep amount (seconds): Default 60
+        -f, --fail="script +cmds"        Fail Script: run in case of final failure
+    
+### Examples
+
+No problem:
+
+`retry echo u work good`
+
+    u work good
+
+Test functionality:
+
+`retry 'echo "y u no work"; false'`
+
+    y u no work
+    Before retry #1: sleeping 0.3 seconds
+    y u no work
+    Before retry #2: sleeping 0.6 seconds
+    y u no work
+    Before retry #3: sleeping 1.2 seconds
+    y u no work
+    Before retry #4: sleeping 2.4 seconds
+    y u no work
+    Before retry #5: sleeping 4.8 seconds
+    y u no work
+    Before retry #6: sleeping 9.6 seconds
+    y u no work
+    Before retry #7: sleeping 19.2 seconds
+    y u no work
+    Before retry #8: sleeping 38.4 seconds
+    y u no work
+    Before retry #9: sleeping 60.0 seconds
+    y u no work
+    Before retry #10: sleeping 60.0 seconds
+    y u no work
+    etc..
+
+Limit retries:
+
+`retry -t 4 'echo "y u no work"; false'`
+
+    y u no work
+    Before retry #1: sleeping 0.3 seconds
+    y u no work
+    Before retry #2: sleeping 0.6 seconds
+    y u no work
+    Before retry #3: sleeping 1.2 seconds
+    y u no work
+    Before retry #4: sleeping 2.4 seconds
+    y u no work
+    Retries exhausted
+
+Bad command:
+
+`retry poop`
+
+    bash: poop: command not found
+
+Fail command:
+
+`retry -t 3 -f 'echo "oh poopsickles"' 'echo "y u no work"; false'`
+
+    y u no work
+    Before retry #1: sleeping 0.3 seconds
+    y u no work
+    Before retry #2: sleeping 0.6 seconds
+    y u no work
+    Before retry #3: sleeping 1.2 seconds
+    y u no work
+    Retries exhausted, running fail script
+    oh poopsickles
+
+Last attempt passed:
+
+`retry -t 3 -- 'if [ $RETRY_ATTEMPT -eq 3 ]; then echo Passed at attempt $RETRY_ATTEMPT; true; else echo Failed at attempt $RETRY_ATTEMPT; false; fi;'`
+
+    Failed at attempt 0
+    Before retry #1: sleeping 0.3 seconds
+    Failed at attempt 1
+    Before retry #2: sleeping 0.6 seconds
+    Failed at attempt 2
+    Before retry #3: sleeping 1.2 seconds
+    Passed at attempt 3
+
+### License
+
+Apache 2.0 - go nuts