SCIM 2.0 filter

This package includes 'parser', 'lexer' and 'evaluator'.
The parser program is generated by goyacc.

Install

go get github.com/hiyosi/filter

Usage

func main() {
	env := filter.Env{}
	s := new(filter.Scanner)
	s.Init("ham eq \"spam\"")
	statements := filter.Parse(s)
	query, err := filter.Evaluate(statements[0], env)
	if err != nil {
	        fmt.Printf("error")
	}
    
	fmt.Printf("%s\n", query)  // result is output as string.
 }

map[ham:spam]

As above, result data type is map[string]interface{}.
For instance, you can use this result to arguments of bson.M

• http://godoc.org/labix.org/v2/mgo/bson#M

Generate parser.go from parser.go.y

$ cd filter
$ make

Implemented operators are follows

status	Operator	Description
✓	eq	equal
✓	ne	not equal
✓	co	contains
✓	sw	starts with
✓	ew	ends with
✓	pr	present (has value?
✓	gt	greater than
✓	ge	greater than equal
✓	lt	less than
✓	le	less than equal
✓	and	Logical and
✓	or	Logical or
✓	not	Not function
✓	()	Precedence grouping
✓	[]	Complex attribute filter grouping

• https://tools.ietf.org/html/draft-ietf-scim-api-14#section-3.2.2

result example

• Input data

userName eq "bjensen"
name.familyName co "O'Malley"
userName sw "J"
title pr
(title pr)
meta.lastModified gt "2011-05-13T04:42:34Z"
meta.lastModified ge "2011-05-13T04:42:34Z"
meta.lastModified lt "2011-05-13T04:42:34Z"
meta.lastModified le "2011-05-13T04:42:34Z"
title pr and userType eq "Employee"
title pr or userType eq "Intern"
schemas eq "urn:ietf:params:scim:schemas:extension:enterprise:2.0:User"
userType eq "Employee" and (emails co "example.com" or emails co "example.org")
userType eq "Employee" and ( emails co "example.com" or emails co "example.org")
userType eq "Employee" and (emails co "example.com" or emails co "example.org" )
userType eq "Employee" and ( emails co "example.com" or emails co "example.org" )
userType ne "Employee" and not ( emails co "example.com" or  emails co "example.org" )
userType eq "Employee" and ( emails.type eq "work" )
userType eq "Employee" and emails[type eq "work" and value co "@example.com"]
emails[type eq "work" and value co "@example.com"] or ims[type eq "xmpp" and value co "@foo.com"]

• result

map[userName:bjensen]
map[name.familyName:map[$regex:{O'Malley }]]
map[userName:map[$regex:{^J }]]
map[title:map[$exists:true]]
map[title:map[$exists:true]]
map[meta.lastModified:map[$gt:2011-05-13 04:42:34 +0000 UTC]]
map[meta.lastModified:map[$gte:2011-05-13 04:42:34 +0000 UTC]]
map[meta.lastModified:map[$lt:2011-05-13 04:42:34 +0000 UTC]]
map[meta.lastModified:map[$lte:2011-05-13 04:42:34 +0000 UTC]]
map[$and:[map[title:map[$exists:true]] map[userType:Employee]]]
map[$or:[map[title:map[$exists:true]] map[userType:Intern]]]
map[schemas:urn:ietf:params:scim:schemas:extension:enterprise:2.0:User]
map[$and:[map[userType:Employee] map[$or:[map[emails:map[$regex:{example\.com }]] map[emails:map[$regex:{example\.org }]]]]]]
map[$and:[map[userType:Employee] map[$or:[map[emails:map[$regex:{example\.com }]] map[emails:map[$regex:{example\.org }]]]]]]
map[$and:[map[userType:Employee] map[$or:[map[emails:map[$regex:{example\.com }]] map[emails:map[$regex:{example\.org }]]]]]]
map[$and:[map[userType:Employee] map[$or:[map[emails:map[$regex:{example\.com }]] map[emails:map[$regex:{example\.org }]]]]]]
map[$and:[map[userType:map[$ne:Employee]] map[$or:[map[emails:map[$not:map[$regex:{example\.com }]]] map[emails:map[$not:map[$regex:{example\.org }]]]]]]]
map[$and:[map[userType:Employee] map[emails.type:work]]]
map[$and:[map[userType:Employee] map[$and:[map[emails.type:work] map[emails.value:map[$regex:{@example\.com }]]]]]]
map[$or:[map[$and:[map[emails.type:work] map[emails.value:map[$regex:{@example\.com }]]]] map[$and:[map[ims.type:xmpp] map[ims.value:map[$regex:{@foo\.com }]]]]]]

Memo

• Depends on bson.Regex to evaluate regular expression.
  • e.g. co, sw and ew
  • http://godoc.org/labix.org/v2/mgo/bson#RegEx

TODO

• Specified to attribute name with full path with schema URI.( To disambiguate duplicate names between schemas)
  • e.g. filter=urn:ietf:params:scim:schemas:core:2.0:User:userName sw "J"
• Evaluator do not use the Env{} structure.
• Do not use panic.