Define options in usage

homer.py

@@ -101,7 +101,51 @@ def error(msg=None, exit=True):
 def usage(msg=None):
     if msg:
         print(msg,file=sys.stderr)
-    print("Usage: %s [--dot] url-or-servername domain-name [DNS type]" % sys.argv[0], file=sys.stderr)
+    print("Usage: %s [options] url-or-servername [domain-name [DNS type]]" % sys.argv[0], file=sys.stderr)
+    print("""Options
+    -t --dot            Use DoT (by default use DoH)
+    -P --post --POST    Use HTTP POST method for all transfers (DoH only)
+    -e --head --HEAD    Use HTTP HEAD method for all transfers (DoH only)
+    -r --repeat <N>     Perform N times the query. If used with -f, read up to
+                        <N> rows of the <file>.
+    -d --delay <T>      Time to wait in seconds between each synchronous
+                        request (only with --repeat)
+    -f --file <file>    Read domain names from <file>, one per row with an
+                        optional DNS type
+    --check             Perform a set of predefined tests.
+    --mandatory-level <level>
+                        Define the <level> of test to perform (only with
+                        --check)
+                        Available <level> : legal, necessary, nicetohave
+    --multistreams      Use HTTP/2 streams, needs an input file with -f
+                        (DoH only)
+    --sync              Process received queries synchronously (only with
+                        --multistreams)
+    --no-display-results
+                        Disable output of DNS response (only with
+                        --multistreams)
+    --time              Display the time elapsed for the query (only with
+                        --multistreams)
+    --dnssec            Request DNSSEC data (signatures)
+    --noedns            Disable EDNS, default is to indicate EDNS support
+    --ecs               Send ECS to authoritative servers, default is to
+                        refuse it
+    --key <key>         Authenticate a DoT resolver with its public <key> in
+                        base64 (DoT only)
+    --nosni             Do not perform SNI (DoT only)
+    -k --insecure       Do not check the certificate
+    -4 --v4only         Force IPv4 resolution of url-or-servername
+    -6 --v6only         Force IPv6 resolution of url-or-servername
+    -V --vhost <vhost>
+    -v --verbose        Make the program more talkative
+    --debug             Make the program even more talkative than -v
+    -h --help           Print this message
+
+    url-or-servername   The URL or domain name of the DoT/DoH server
+    domain-name         The domain name to resolve, not required if -f is
+                        provided
+    DNS type            The DNS record type to resolve, default AAAA
+    """, file=sys.stderr)
     print("See the README.md for more details.", file=sys.stderr)
 
 def is_valid_hostname(name):