Add bin

bin/bin/retry.sh

@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+
+# Retries a command on failure.
+
+HELP=\
+"$0: $0 [flags] [options] [--] COMMAND
+    Runs a command, retrying if the command fails
+
+    Arguments:
+      COMMAND                    The command to run
+
+    Flags:
+      -h, --help                 Display this message and exit
+      --forever                  Retry until the command succeeds
+
+    Options:
+      -n, --num-attempts number  The maximum number of times to retry the command (default: 10)
+      -d, --delay number         The number of seconds to wait between attempts (default: 3)"
+
+sleep_duration=3
+num_attempts=10
+params=""
+forever=""
+
+while (( "$#" ));
+do
+    case "$1" in
+        -h|--help)
+            echo "$HELP"
+            exit 0
+            ;;
+        --forever)
+            forever=true
+            shift
+            ;;
+        -d|--delay)
+            sleep_duration="$2"
+            shift 2
+            ;;
+        -n|--num-attempts)
+            num_attempts="$2"
+            shift 2
+            ;;
+        --)
+            shift 1
+            params="$params $@"
+            break
+            ;;
+        *)
+            params="$params $1"
+            shift
+            ;;
+    esac
+done
+
+eval set -- "$params"
+
+retry () {
+    local -r -i max_attempts="$1"; shift
+    local -r cmd="$@"
+    local -i attempt_num=1
+
+    until $cmd
+    do
+        attempt_str="$attempt_num/$max_attempts"
+        if [ "$forever" = true ];
+        then
+            attempt_str="$attempt_num"
+        fi
+        if (( attempt_num == max_attempts )) && [ "$forever" != true ];
+        then
+            echo "Attempt $attempt_str failed. Giving up."
+            return 1
+        else
+            echo "Attempt $attempt_str failed. Retrying in $sleep_duration seconds..."
+            ((attempt_num++))
+            sleep "$sleep_duration"
+        fi
+    done
+}
+
+retry "$num_attempts" "$@"