Improve automation: use exit codes to determine success or fail.

1. Run in terminal 1:

$PORT=3100 node app.js

2. Run in terminal 2:

$( ./verifyscript.sh && if [ $? -lt 0 ]; then echo "failure, exit code -1"; elif [ $? -eq 0 ]; then echo "success, exit code 0"; elif [ $? -lt 0 ]; then echo "failure, exit code less than 1"; elif [ $? -gt 1 ]; then echo "exit code greater than 1"; fi )

3. Result in terminal 2: expected output:

radsauce
success, child process exit code 0: OUTPUT is radsauce

4. Result in termimal 1: expected output:

radsauce

5. Note: the $? -lt 0 logic, meaning if process' exit code is less than 0, was used on the
command line, in addition to logic of string comparison within verifyscript.sh.

Which is most effective?

Author: abstractmachines

app.js

@@ -28,8 +28,8 @@
 	* header to plain text, and verify the output by echoing the
 	* -d data=variable in the server response (the POST handler below):
   *
-	* $ curl -X POST -d name=radsauce http://localhost:3100/foo -v
-  * -H "Content-Type: text/plain" 
+	* $ curl -X POST -d name=radsauce http://localhost:3100/foo 
+  * -H "Content-Type: text/plain"
   *
   * The above changes existing Content-Type HTTP header to send a MIME type /
   * data type message of plain text. (Default is urlencoded).

package.json

@@ -2,13 +2,13 @@
   "name": "helloworld",
   "version": "1.0.0",
   "description": "a first Express.js project. August 7th 2016, AF.",
-  "main": "index.js",
+  "main": "app.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "repository": {
     "type": "git",
-    "url": ""
+    "url": "github.com/abstractmachines/express1"
   },
   "author": "A. Falke",
   "license": "ISC",

verifyscript.sh

@@ -4,16 +4,24 @@
 #expected output after terminal 2 curl's:
 #radsauce
 
-#terminal 2:  ./verifyscript.sh && echo "it worked" || echo "fail"
-#expected output:
+#terminal 2:  ./verifyscript.sh && echo "it worked" || echo "fail" etc
+#
+# Specific command to run in terminal 2 is:
+#
+# ( ./verifyscript.sh && if [ $? -lt 0 ];
+# then echo "failure, exit code -1";
+# elif [ $? -eq 0 ]; then echo "success, exit code 0";
+# elif [ $? -lt 0 ]; then echo "failure, exit code less than 1";
+# elif [ $? -gt 1 ]; then echo "exit code greater than 1"; fi )
 # radsauce
 # success, child process exit code 0: OUTPUT is radsauce
-# it worked
 
 OUTPUT="$(curl --request POST -d radsauce http://localhost:3100/foo -H "Content-Type: text/plain" 2>/dev/null )"
 
 echo "${OUTPUT}"
 
+# possible alternative:
+# if [ $? -eq 0 ]; then
 
 if [ "${OUTPUT}" = "radsauce" ]; then