[FEATURE] ws2rpc improvements -- proper argparsing, offline mode, specify rippled instance from commandline

tool/ws2rpc.py

@@ -7,15 +7,18 @@ a public WebSocket server.
 """
 
 from __future__ import print_function
-import re, json
-import sys
-import warnings
+import re, json, sys, warnings, argparse
+
 if sys.version_info[:2] <= (2,7):
     import httplib
+    #gotta define this
+    class FileNotFoundError(IOError):
+        pass
 else:
     import http.client as httplib
 
-WS_REGEX = r"\*WebSocket\*\s*```\s*(?P<json>\{[^`]*\})\s*```"
+RIPPLED_RPC_HOST = "s1.ripple.com"
+RIPPLED_RPC_PORT = 51234
 
 def ws2rpc(s):    
     ws_j = json.loads(s)
@@ -36,34 +39,51 @@ def ws2rpc(s):
             
     return json.dumps(rpc_j, sort_keys=True, indent=4, separators=(',', ': '))
     
+def do_JSONRPC(req, host, port):
+    conn = httplib.HTTPConnection(host, port)
+    conn.request("POST", "/", js)
+    response = conn.getresponse()
+    
+    s = response.read()
+    header = "%s %s" % (response.status, response.reason)
+    return (header, s)
+    
 
 if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Convert WebSocket examples to JSON-RPC with responses from the live rippled network")
+    parser.add_argument("inputfile")
+    parser.add_argument("--offline", action="store_true", help="don't connect to the network to generate responses")
+    parser.add_argument("--rippled_host", help="hostname of a rippled server to use", type=str, default=RIPPLED_RPC_HOST)
+    parser.add_argument("--rippled_port", help="port number of a rippled server to use", type=int, default=RIPPLED_RPC_PORT)
     
-    if len(sys.argv) != 2:
-        exit("Usage: %s inputfile" % sys.argv[0])
+    args = parser.parse_args()
     
-    f = open(sys.argv[1], 'r')
-    matches = re.findall(WS_REGEX, f.read())
-    f.close()
+    WS_REGEX = r"\*WebSocket\*\s*```\s*(?P<json>\{[^`]*\})\s*```"
+    
+    try:
+        f = open(args.inputfile, 'r')
+        matches = re.findall(WS_REGEX, f.read())
+        f.close()
+    except (FileNotFoundError, IOError, OSError):
+        exit("Couldn't read file %s" % args.inputfile)
     
     for s in matches:
         js = ws2rpc(s)
         if js:
-            print("Request:\n*JSON-RPC*\n```\n"+js+"\n```\n\n")
+            print("Request:\n*JSON-RPC*\n\n```\n"+js+"\n```\n\n")
             
-            conn = httplib.HTTPConnection("s1.ripple.com", 51234)
-            conn.request("POST", "/", js)
-            response = conn.getresponse()
-            
-            s = response.read()
+            if args.offline:
+                continue
+                
+            header, response_body = do_JSONRPC(js, args.rippled_host, args.rippled_port)
             
             try:
                 #parse & pretty-print response JSON if valid
-                response_json = json.loads(s.decode("utf-8"))
-                s = json.dumps(response_json, sort_keys=True, indent=4, separators=(',', ': '))
+                response_json = json.loads(response_body.decode("utf-8"))
+                response_body = json.dumps(response_json, sort_keys=True, indent=4, separators=(',', ': '))
             except ValueError:
                 #invalid JSON; leave response as-is
                 pass
         
-            print("Response:\n*JSON-RPC*\n```\n%s %s\n%s```\n\n" % (
-                    response.status, response.reason, s) )
+            print("Response:\n*JSON-RPC*\n\n```\n%s\n%s\n```\n\n" % (
+                    header, response_body) )