A fully compliant implementation of JMESPath for .Net Core.
JMESPath.Net uses Newtonsoft.Json to handle JSON
and comes with a simple to use parser:
using DevLab.JmesPath;
const string input = @"{ \"foo\": \"bar\" }";
const string expression = "foo";
var jmes = new JmesPath();
var result = jmes.Transform(input, expression);The JmesPath.Transform method accepts and produces well formed JSON constructs (object, array or string, boolean, number and null values).
In the example above, the result is a JSON string token, including the quotes.
using Newtonsoft.Json.Linq;
System.Diagnostics.Debug.Assert(result == "\"bar\"");
var token = JToken.Parse(result);
var text = token.ToString();
System.Diagnostics.Debug.Assert(text == "bar");The previous example return the result of the JMESPath evaluation in a single function call.
The JMESPath.Net parser, however, create an abstract syntax tree with a root JmesPathExpression object used for evaluating JMESPath expression against a JSON document.
If you want to retrieve the AST before performing evaluations, use the following code:
var jp = new JmesPath();
var ast = jp.Parse(expression);
System.Diagnostics.Debug.Assert(ast is JmesPathExpression);Here is the inheritance hierarchy of JmesPathExpression objects:
classDiagram
class JmesPathExpression
JmesPathExpression: +bool IsExpressionType()
JmesPathExpression <|-- JmesPathSimpleExpression
JmesPathExpression <|-- JmesPathCompoundExpression
JmesPathExpression <|-- JmesPathProjection
JmesPathExpression <|-- JmesPathFunctionExpression
JmesPathExpression <|-- JmesPathLetExpression
JmesPathExpression <|-- JmesPathVariableReference
JmesPathFunctionExpression: +string Name
JmesPathFunctionExpression: +JmesPathExpression[] Arguments
classDiagram
JmesPathExpression <|-- JmesPathCurrentNode
JmesPathExpression <|-- JmesPathIdentifier
JmesPathExpression <|-- JmesPathIndex
JmesPathExpression <|-- JmesPathLiteral
JmesPathExpression <|-- JmesPathMultiSelectHash
JmesPathExpression <|-- JmesPathMultiSelectList
JmesPathExpression <|-- JmesPathRawString
JmesPathMultiSelectList: +JmesPathExpression[] Expressions
JmesPathMultiSelectHash: +IDictionary~string, JmesPathExpression~ Dictionary
JmesPathIdentifier: +string Name
JmesPathIndex: +int Index
JmesPathLiteral: +JToken Value
JmesPathRawString: + string Value
A simple expression encapsulates a single instance of another expression named Expression.
classDiagram
class JmesPathSimpleExpression
JmesPathSimpleExpression: +JmesPathExpression Expression
JmesPathSimpleExpression <|-- JmesPathNotExpression
JmesPathSimpleExpression <|-- JmesPathParenExpression
Compound expressions are a combination of two expressions, named Left and Right.
classDiagram
class JmesPathCompoundExpression
JmesPathCompoundExpression: +JmesPathExpression Left
JmesPathCompoundExpression: +JmesPathExpression Right
JmesPathCompoundExpression <|-- JmesPathAndExpression
JmesPathCompoundExpression <|-- JmesPathComparison
JmesPathCompoundExpression <|-- JmesPathIndexExpression
JmesPathCompoundExpression <|-- JmesPathOrExpression
JmesPathCompoundExpression <|-- JmesPathPipeExpression
JmesPathCompoundExpression <|-- JmesPathSubExpression
classDiagram
JmesPathProjection <|-- JmesPathFilterProjection
JmesPathProjection <|-- JmesPathFlattenProjection
JmesPathProjection <|-- JmesPathHashWildcardProjection
JmesPathProjection <|-- JmesPathListWildcardProjection
JmesPathProjection <|-- JmesPathSliceProjection
JmesPathFilterProjection: +JmesPathExpression Expression
JmesPathSliceProjection: +int? Start
JmesPathSliceProjection: +int? Stop
JmesPathSliceProjection: +int? Step
classDiagram
JmesPathComparison <|-- JmesPathEqualOperator
JmesPathComparison <|-- JmesPathOrderingComparison
JmesPathComparison <|-- JmesPathNotEqualOperator
classDiagram
JmesPathOrderingComparison <|-- JmesPathGreaterThanOperator
JmesPathOrderingComparison <|-- JmesPathGreaterThanOrEqualOperator
JmesPathOrderingComparison <|-- JmesPathLessThanOperator
JmesPathOrderingComparison <|-- JmesPathLessThanOrEqualOperator