18 releases (1 stable)

1.0.0 Aug 30, 2022
0.3.9 Mar 14, 2022
0.3.8 Dec 17, 2021
0.3.6 Nov 29, 2021
0.2.1 Feb 5, 2021

#684 in Database interfaces

MIT/Apache

51KB
1.5K SLoC

FLP-GSP

Crates.io Version

General Search Parser

General Search String (GSS) Builder

Goto the page.

General Search String (GSS) LALR(1) Grammar

    Search -> Relation

  Relation -> GroupStart Comparison GroupEnd
           -> GroupStart Relation And Relation GroupEnd
           -> GroupStart Relation And Comparison GroupEnd
           -> GroupStart Comparison And Relation GroupEnd
           -> GroupStart Comparison And Comparison GroupEnd
           -> GroupStart Relation Or Relation GroupEnd
           -> GroupStart Relation Or Comparison GroupEnd
           -> GroupStart Comparison Or Relation GroupEnd
           -> GroupStart Comparison Or Comparison GroupEnd
           -> GroupStart Not Relation GroupEnd
           -> GroupStart Not Comparison GroupEnd

Comparison -> Str Equal Str
           -> Str EqualCI Str
           -> Str Greater Str
           -> Str Less Str
           -> Str Wildcard Str
           -> Str Regex Str
           -> Str Any Array
           -> Str Null

       Str -> DoubleQuote Content DoubleQuote
       
     Array -> SquareBracketLeft (Str Comma)* SquareBracketRight

GroupStart -> (

  GroupEnd -> )

       And -> &

        Or -> |

       Not -> !

     Equal -> =

   EqualCI -> ~

   Greater -> >

      Less -> <

  Wildcard -> *

     Regex -> $
     
       Any -> ?

      Null -> -

Interpreter

Some example interpreters that maybe useful, need to be enabled by feature

Evaluate ["evaluate"]

Customizable in-code evaluating interpreter. Goto the file.

An example could be found here.

Concept

To evaluate a Search, you will need EvaluateRules and EvaluatePairs.

  • EvaluateRules: You can overwrite any default rules for comparison. Usually, you may want to overwrite is_greater_than and is_less_than if the key has a numeric value. Rules should be reused as often as possible in order to reduce redundant codes.

  • EvaluatePairs: Actual key-value pairs for the evaluation. You need to parse your values into strings so that rules can be applied.

Mysql ["mysql"]

Generating Mysql condition clause. Goto the file.

An example could be found here.

The types can be used in sqlx^0.5 binding directly.

Concept

To generate Mysql condition clause from a Search, you will need MysqlRenames and MysqlTypes.

  • MysqlRenames: You can insert any rename rules to it. E.g. key sex in search string may need to be renamed to table_a.gender regarding the actual query string. All keys without rename rules will stay as is.

  • MysqlTypes: You can insert any types to it. You need this because the condition clause is a prepare clause (i.e. all values are replaced as placeholder(?)) and you will be given a Vec with search targets in the order that "?"s appear in the clause. For details, please read the example. Additionally, MysqlType::StringLike(String) is the default type if you didn't insert types for one or some keys.

Postgres ["postgres"]

Very similar to Mysql except for some types.

The types can be used in sqlx^0.5 binding directly, except several types defined by sqlx itself, e.g. PgInterval, PgMoney, etc.

Special Types

  • VarBit: target need to be in format of <u64>. E.g. 1024 stands for bits 0000010000000000

Dependencies

~3.5–5.5MB
~101K SLoC