MINOR: sample: Add converters to parse FIX messages
This patch implements a couple of converters to validate and extract tag value
from a FIX (Financial Information eXchange) message. The validation consists in
a few checks such as mandatory fields and checksum computation. The extraction
can get any tag value based on a tag string or tag id.
This patch requires the istend() function. Thus it depends on "MINOR: ist: Add
istend() function to return a pointer to the end of the string".
Reviewed and Fixed by Christopher Faulet <cfaulet@haproxy.com>
diff --git a/doc/configuration.txt b/doc/configuration.txt
index e85c525..a7dc4b6 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -15133,6 +15133,52 @@
str(f1_f2_f3__f5),field(-2,_,3) # f2_f3_
str(f1_f2_f3__f5),field(-3,_,0) # f1_f2_f3
+fix_is_valid
+ Parses a binary payload and performs sanity checks regarding FIX (Financial
+ Information eXchange):
+
+ - checks that all tag IDs and values are not empty and the tags IDs are well
+ numeric
+ - checks the BeginString tag is the first tag with a valide FIX version
+ - checks the BodyLength tag is the second one with the right body length
+ - checks the MstType tag is the third tag.
+ - checks that last tag in the message is the CheckSum tag with a valid
+ checksum
+
+ Due to current HAProxy design, only the first message sent by the client and
+ the server can be parsed.
+
+ This converter returns a boolean, true if the payload contains a valid FIX
+ message, false if not.
+
+ See also the fix_tag_value converter.
+
+ Example:
+ tcp-request inspect-delay 10s
+ tcp-request content reject unless { req.payload(0,0),fix_is_valid }
+
+fix_tag_value(<tag>)
+ Parses a FIX (Financial Information eXchange) message and extracts the value
+ from the tag <tag>. <tag> can be a string or an integer pointing to the
+ desired tag. Any integer value is accepted, but only the following strings
+ are translated into their integer equivalent: BeginString, BodyLength,
+ MsgType, SenderComID, TargetComID, CheckSum. More tag names can be easily
+ added.
+
+ Due to current HAProxy design, only the first message sent by the client and
+ the server can be parsed. No message validation is performed by this
+ converter. It is highly recommended to validate the message first using
+ fix_is_valid converter.
+
+ See also the fix_is_valid converter.
+
+ Example:
+ tcp-request inspect-delay 10s
+ tcp-request content reject unless { req.payload(0,0),fix_is_valid }
+ # MsgType tag ID is 35, so both lines below will return the same content
+ tcp-request content set-var(txn.foo) req.payload(0,0),fix_tag_value(35)
+ tcp-request content set-var(txn.bar) req.payload(0,0),fix_tag_value(MsgType)
+
hex
Converts a binary input sample to a hex string containing two hex digits per
input byte. It is used to log or transfer hex dumps of some binary input data