feat: adds support for http using wget

Implements #14

Author: Addono

README.md

@@ -43,7 +43,7 @@ Download the `wait-for` file, either the latest from [`master`](https://raw.gith
 With the file locally on your file system, you can directly invoke it.
 
 ```
-./wait-for host:port [-t timeout] [-- command args]
+./wait-for host:port|url [-t timeout] [-- command args]
   -q | --quiet                        Do not output any status messages
   -t TIMEOUT | --timeout=timeout      Timeout in seconds, zero for no timeout
   -- COMMAND ARGS                     Execute command with args after the test finishes
@@ -69,8 +69,8 @@ Eficode site is up
 To wait for database container to become available:
 
 
-```
-version: '2'
+```yml
+version: '3'
 
 services:
   db:
@@ -83,6 +83,30 @@ services:
       - db
 ```
 
+To check if [https://www.eficode.com](https://www.eficode.com) is available over HTTPS:
+```
+$ ./wait-for https://www.eficode.com -- echo "Eficode is accessible over HTTPS"
+Eficode is accessible over HTTPS
+```
+
+To wait for your API service to become available:
+
+
+```yml
+version: '3'
+
+services:
+  api:
+    image: nginx
+
+  tests:
+    build: .
+    command: sh -c './wait-for http://api -- echo "The api is up! Let's use it"'
+    depends_on:
+      - api
+
+```
+
 ## Testing
 
 Ironically testing is done using [bats](https://github.com/sstephenson/bats), which on the other hand is depending on [bash](https://en.wikipedia.org/wiki/Bash_(Unix_shell)).
@@ -100,9 +124,11 @@ Also, please include or update the test cases whenever possible by extending `wa
 
 ## Note
 
-Make sure netcat is installed in your Dockerfile before running the command.
+Make sure netcat is installed in your Dockerfile before running the command if you test over plain TCP.
 ```
 RUN apt-get -q update && apt-get -qy install netcat
 ```
 https://stackoverflow.com/questions/44663180/docker-why-does-wait-for-always-time-out
 
+If you are connecting over HTTP, then you will need to have wget available.
+ 

wait-for

@@ -22,9 +22,11 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-set -- "$@" -- "$TIMEOUT" "$QUIET" "$HOST" "$PORT" "$result"
+set -- "$@" -- "$TIMEOUT" "$QUIET" "$PROTOCOL" "$HOST" "$PORT" "$result"
 TIMEOUT=15
 QUIET=0
+# The protocol to make the request with, either "tcp" or "http"
+PROTOCOL="tcp"
 
 echoerr() {
   if [ "$QUIET" -ne 1 ]; then printf "%s\n" "$*" 1>&2; fi
@@ -34,7 +36,7 @@ usage() {
   exitcode="$1"
   cat << USAGE >&2
 Usage:
-  $cmdname host:port [-t timeout] [-- command args]
+  $cmdname host:port|url [-t timeout] [-- command args]
   -q | --quiet                        Do not output any status messages
   -t TIMEOUT | --timeout=timeout      Timeout in seconds, zero for no timeout
   -- COMMAND ARGS                     Execute command with args after the test finishes
@@ -43,25 +45,47 @@ USAGE
 }
 
 wait_for() {
- if ! command -v nc >/dev/null; then
-    echoerr 'nc command is missing!'
-    exit 1
-  fi
+  case "$PROTOCOL" in
+    tcp)
+      if ! command -v nc >/dev/null; then
+        echoerr 'nc command is missing!'
+        exit 1
+      fi
+      ;;
+    wget)
+      if ! command -v wget >/dev/null; then
+        echoerr 'nc command is missing!'
+        exit 1
+      fi
+      ;;
+  esac
 
   while :; do
-    nc -z "$HOST" "$PORT" > /dev/null 2>&1
-    
+    case "$PROTOCOL" in
+      tcp) 
+        nc -z "$HOST" "$PORT" > /dev/null 2>&1
+        ;;
+      http)
+        wget --timeout=1 -q "$HOST" -O /dev/null > /dev/null 2>&1 
+        ;;
+      *)
+        echoerr "Unknown protocol '$PROTOCOL'"
+        exit 1
+        ;;
+    esac
+
     result=$?
+        
     if [ $result -eq 0 ] ; then
-      if [ $# -gt 6 ] ; then
-        for result in $(seq $(($# - 6))); do
+      if [ $# -gt 7 ] ; then
+        for result in $(seq $(($# - 7))); do
           result=$1
           shift
           set -- "$@" "$result"
         done
 
-        TIMEOUT=$2 QUIET=$3 HOST=$4 PORT=$5 result=$6
-        shift 6
+        TIMEOUT=$2 QUIET=$3 PROTOCOL=$4 HOST=$5 PORT=$6 result=$7
+        shift 7
         exec "$@"
       fi
       exit 0
@@ -80,6 +104,11 @@ wait_for() {
 
 while :; do
   case "$1" in
+    http://*|https://*)
+    HOST="$1"
+    PROTOCOL="http"
+    shift 1
+    ;;
     *:* )
     HOST=$(printf "%s\n" "$1"| cut -d : -f 1)
     PORT=$(printf "%s\n" "$1"| cut -d : -f 2)
@@ -137,9 +166,19 @@ if ! [ "$TIMEOUT" -ge 0 ] 2>/dev/null; then
   usage 3
 fi
 
-if [ "$HOST" = "" -o "$PORT" = "" ]; then
-  echoerr "Error: you need to provide a host and port to test."
-  usage 2
-fi
+case "$PROTOCOL" in
+  tcp)
+    if [ "$HOST" = "" -o "$PORT" = "" ]; then
+      echoerr "Error: you need to provide a host and port to test."
+      usage 2
+    fi
+  ;;
+  http)
+    if [ "$HOST" = "" ]; then
+      echoerr "Error: you need to provide a host to test."
+      usage 2
+    fi
+  ;;
+esac
 
 wait_for "$@"

wait-for.bats

@@ -33,15 +33,54 @@
   [ "$output" != "success" ]
 }
 
-@test "environment variables should be restored for command invocation" {
+@test "environment variable HOST should be restored for command invocation" {
   HOST=success run ./wait-for -t 1 google.com:80 -- sh -c 'echo "$HOST"'
 
   [ "$output" = "success" ]
 }
 
-@test "unset environment variables should be restored as unset for command invocation" {
+@test "unset environment variable HOST should be restored as unset for command invocation" {
   run ./wait-for -t 1 google.com:80 -- sh -uc 'echo "$HOST"'
 
   [ "$status" -ne 0 ]
   [ "$output" != "google.com" ]
 }
+
+@test "environment variable PROTOCOL should be restored for command invocation" {
+  PROTOCOL=success run ./wait-for -t 1 google.com:80 -- sh -c 'echo "$PROTOCOL"'
+
+  [ "$output" = "success" ]
+}
+
+@test "unset environment variables PROTOCOL should be restored as unset for command invocation" {
+  run ./wait-for -t 1 google.com:80 -- sh -uc 'echo "$PROTOCOL"'
+
+  [ "$status" -ne 0 ]
+  [ "$output" != "google.com" ]
+}
+
+@test "http://duckduckgo.com should be immediately found" {
+  run ./wait-for http://duckduckgo.com -- echo 'success'
+
+  [ "$output" = "success" ]
+}
+
+@test "https://duckduckgo.com should be immediately found" {
+  run ./wait-for https://duckduckgo.com -- echo 'success'
+
+  [ "$output" = "success" ]
+}
+
+@test "connection error in HTTP test should not start command" {
+  run ./wait-for -t 1 http://google.com:8080 -- echo 'success'
+
+  [ "$status" -ne 0 ]
+  [ "$output" != "success" ]
+}
+
+@test "not found HTTP status should not start command" {
+  run ./wait-for -t 1 http://google.com/ping -- echo 'success'
+
+  [ "$status" -ne 0 ]
+  [ "$output" != "success" ]
+}