Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/kanety/logical_query_parser
A parser to generate a tree structure from a logical search query string using treetop.
https://github.com/kanety/logical_query_parser
Last synced: 2 months ago
JSON representation
A parser to generate a tree structure from a logical search query string using treetop.
- Host: GitHub
- URL: https://github.com/kanety/logical_query_parser
- Owner: kanety
- License: mit
- Created: 2016-10-12T01:30:49.000Z (over 8 years ago)
- Default Branch: master
- Last Pushed: 2024-10-21T00:43:17.000Z (3 months ago)
- Last Synced: 2024-10-21T04:07:33.509Z (3 months ago)
- Language: Ruby
- Homepage:
- Size: 48.8 KB
- Stars: 6
- Watchers: 3
- Forks: 2
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE.txt
- Code of conduct: CODE_OF_CONDUCT.md
Awesome Lists containing this project
README
# LogicalQueryParser
A parser to generate a tree structure from a logical search query string using treetop.
## Dependencies
* ruby 2.3+
* treetop 1.6+
* activerecord 4.2+ (optional)
## Installation
Add this line to your application's Gemfile:
```ruby
gem 'logical_query_parser'
```
And then execute:
$ bundle
Or install it yourself as:
$ gem install logical_query_parser
## Usage
You can parse a logical query string as follows:
```ruby
parser = LogicalQueryParser.new
parser.parse('a AND b')
# return value is a syntax tree of treetop
=> SyntaxNode+Exp0+ExpNode offset=0, "a AND b" (any):
SyntaxNode+Cond0+CondNode offset=0, "a AND b" (lexp,logic,rexp):
SyntaxNode+Literal0+LiteralNode offset=0, "a" (word,negative):
SyntaxNode offset=0, ""
SyntaxNode+WordNode offset=0, "a":
SyntaxNode+Atom0 offset=0, "a":
SyntaxNode offset=0, ""
SyntaxNode offset=0, "a"
SyntaxNode offset=1, " ":
SyntaxNode offset=1, " "
SyntaxNode+AndNode offset=2, "AND"
SyntaxNode offset=5, " ":
SyntaxNode offset=5, " "
SyntaxNode+Exp0+ExpNode offset=6, "b" (any):
SyntaxNode+Literal0+LiteralNode offset=6, "b" (word,negative):
SyntaxNode offset=6, ""
SyntaxNode+WordNode offset=6, "b":
SyntaxNode+Atom0 offset=6, "b":
SyntaxNode offset=6, ""
SyntaxNode offset=6, "b"
```
You can parse quoted strings:
```
parser = LogicalQueryParser.new
parser.parse('("a a" AND "b b") OR (c AND d)')
```
You can also parse negative conditions:
```
parser = LogicalQueryParser.new
parser.parse('("a a" AND NOT "b b") OR (c AND -d)')
```
### Supported operators
* AND / and / &: represents an AND logic.
* OR / or / |: represents an OR logic.
* NOT / \-: represents a NOT logic. This should precede to a word or a parenthesis.
* (: represents beginning of a nested expression.
* ): represents end of a nested expression.
* ": represents beginning or end of a quoted word.
* Space: represents a boundary between two words.
For more information, see [grammar definition](lib/logical_query_parser.treetop).
### Use with ActiveRecord
You can use a syntax tree to compile a SQL statement for activerecord. For example:
```ruby
class Doc < ActiveRecord::Base
end
LogicalQueryParser.search("a AND b", Doc.all, :c1, :c2).to_sql
# SELECT "docs".* FROM "docs"
# WHERE (("docs"."c1" LIKE '%a%' OR "docs"."c2" LIKE '%a%') AND ("docs"."c1" LIKE '%b%' OR "docs"."c2" LIKE '%b%'))
```
Use with associations:
```ruby
class Doc < ActiveRecord::Base
has_many :tags
end
class Tag < ActiveRecord::Base
end
LogicalQueryParser.search("a AND b", Doc.all, :c1, :c2, tags: [:c3]).to_sql
# SELECT "docs".* FROM "docs"
# INNER JOIN "tags" ON "tags"."doc_id" = "docs"."id"
# WHERE ((("docs"."c1" LIKE '%a%' OR "docs"."c2" LIKE '%a%') OR "tags"."c3" LIKE '%a%') AND
# (("docs"."c1" LIKE '%b%' OR "docs"."c2" LIKE '%b%') OR "tags"."c3" LIKE '%b%'))
```
## Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/kanety/logical_query_parser.
## License
The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).