HashN
The HashN
parameter specifies a Lua script to use for family hashing. The script should insert an MD5 field into the document, which is a hash of the document’s unique fields. To use this you must set ImportHashFamilies
=true
.
If the Lua script returns false
then the hash is calculated from the whole of the original document (it does not matter whether the document is text or binary). Your script should return true
only when it has set a field called "MD5" containing the hash to use for the document.
In the example below, hash.lua
is used to generate the hash for each document. An example hash.lua
is given below:
function handler(document) if document:getFieldValue("MAIL") == "TRUE" then local toHash = allValues(document, "To" ) .. "||" .. allValues(document, "From" ) .. "||" .. allValues(document, "Subject" ) .. "||" .. allValues(document, "Sent" ); document:addField( "MD5", hash_string( toHash, "MD5" ) ); return true; end return false; end function allValues(document, fieldName) return table.concat({ document:getFieldValues(fieldName) }, ";"); end
When this script is used, if the document has a field called "MAIL" set to "TRUE" then the hash is generated from the "To", "From", "Subject" and "Sent" fields. For all other items the whole document is used to generate the hash.
Type: | String |
Default: | None |
Required: | No |
Configuration Section: | ImportTasks |
Example: | Hash0=Lua:hash.lua
|
See Also |