feat: more tests; more expression-funcs; added data.Value#List()

data/value.go

@@ -2,6 +2,7 @@ package data
 
 import (
 	"fmt"
+	"reflect"
 	"time"
 )
 
@@ -58,3 +59,17 @@ func (val Value) Float64() (float64, error) {
 	}
 	return f, nil
 }
+
+// List will return a slice if the underlying type is either a slice or an array.
+// In all other cases, an error is returned.
+func (val Value) List() ([]interface{}, error) {
+	if !IsArray(val.Raw) {
+		return nil, fmt.Errorf("value is not a list")
+	}
+	rawSlice := reflect.ValueOf(val.Raw)
+	list := make([]interface{}, rawSlice.Len())
+	for i := 0; i < rawSlice.Len(); i++ {
+		list[i] = rawSlice.Index(i).Interface()
+	}
+	return list, nil
+}

expression.go

@@ -6,8 +6,6 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/davecgh/go-spew/spew"
-
 	"github.com/lukasjarosch/skipper/data"
 	"github.com/lukasjarosch/skipper/expression"
 	"github.com/lukasjarosch/skipper/graph"
@@ -121,6 +119,9 @@ func (m *ExpressionManager) executeExpression(expr *expression.ExpressionNode) (
 	return data.NilValue, nil
 }
 
+// pathValueProvider is used as a data context for executing expressions.
+// It is used to dynamically create a map of paths which provide all
+// necessary data to execute an expression.
 type pathValueProvider map[string]interface{}
 
 func (pvp pathValueProvider) GetPath(path data.Path) (interface{}, error) {
@@ -219,7 +220,7 @@ func (m *ExpressionManager) ExecuteInput(input string) (data.Value, error) {
 		for i, expr := range expressions {
 			result, err := expression.Execute(expr, valueProvider, m.variables.GetAll(), nil)
 			if err != nil {
-				return data.NilValue, fmt.Errorf("failed to execute expression at path '%s': %w", pathVertex, err)
+				return data.NilValue, fmt.Errorf("failed to execute expression '%s' at path '%s': %w", expr.Text(), pathVertex, err)
 			}
 			pathResults[i] = result
 		}
@@ -248,12 +249,9 @@ func (m *ExpressionManager) ExecuteInput(input string) (data.Value, error) {
 			oldValue := sourceValue.String()[exprOffsets[0]:exprOffsets[1]]
 			newValue := strings.Replace(sourceValue.String(), oldValue, data.NewValue(result).String(), 1)
 			valueProvider[pathVertex] = newValue
-			spew.Println("ASDF", newValue)
 		}
 	}
 
-	spew.Dump(valueProvider)
-
 	return valueProvider.GetPathValue(data.NewPath(tmpVertexHash))
 }
 

expression/func.go

@@ -1,13 +1,17 @@
 package expression
 
 import (
+	"crypto/sha256"
+	"encoding/hex"
 	"fmt"
 	"os"
 	"reflect"
 	"strings"
 	"sync"
 
 	"github.com/iancoleman/strcase"
+
+	"github.com/lukasjarosch/skipper/data"
 )
 
 type FuncMap map[string]any
@@ -19,7 +23,16 @@ var builtins = FuncMap{
 	"set_env": set_env,
 	"default": defaultFunc,
 
-	// string casing helpers
+	// string
+	"replace":     func(input, search, replace string) string { return strings.ReplaceAll(input, search, replace) },
+	"trim_space":  func(input string) string { return strings.TrimSpace(input) },
+	"trim_all":    func(input, cutset string) string { return strings.Trim(input, cutset) },
+	"trim_left":   func(input, cutset string) string { return strings.TrimLeft(input, cutset) },
+	"trim_right":  func(input, cutset string) string { return strings.TrimRight(input, cutset) },
+	"trim_suffix": func(input, suffix string) string { return strings.TrimSuffix(input, suffix) },
+	"trim_prefix": func(input, prefix string) string { return strings.TrimPrefix(input, prefix) },
+
+	// string case
 	"to_upper":               func(s string) string { return strings.ToUpper(s) },
 	"to_lower":               func(s string) string { return strings.ToLower(s) },
 	"to_snake":               strcase.ToSnake,
@@ -30,6 +43,22 @@ var builtins = FuncMap{
 	"to_lower_camel":         strcase.ToLowerCamel,
 	"to_delimited":           to_delimited,
 	"to_screaming_delimited": to_screaming_delimited,
+
+	// lists
+	"must_first": mustFirst,
+	"first": func(input interface{}) interface{} {
+		first, err := mustFirst(input)
+		if err != nil {
+			panic(err)
+		}
+		return first
+	},
+
+	// crypto
+	"sha256": func(s string) string {
+		hash := sha256.Sum256([]byte(s))
+		return hex.EncodeToString(hash[:])
+	},
 }
 
 var builtinFuncsOnce struct {
@@ -181,3 +210,35 @@ func to_screaming_delimited(str, delim string) string {
 
 	return strcase.ToScreamingDelimited(str, byte(delim[0]), "", true)
 }
+
+// mustFirst attempts to return the first element of the given list.
+func mustFirst(list interface{}) (interface{}, error) {
+	tp := reflect.TypeOf(list).Kind()
+
+	// in case the parameter is `data.Value`, use its means to resolve the first element
+	if val, ok := list.(data.Value); ok {
+		valList, err := val.List()
+		if err != nil {
+			return nil, fmt.Errorf("mustFirst: failed to convert data.Value to list: %w", err)
+		}
+		if len(valList) == 0 {
+			return nil, nil
+		}
+		return valList[0], nil
+	}
+
+	// all other cases: list is not [data.Value]
+	switch tp {
+	case reflect.Slice, reflect.Array:
+		l2 := reflect.ValueOf(list)
+
+		l := l2.Len()
+		if l == 0 {
+			return nil, nil
+		}
+
+		return l2.Index(0).Interface(), nil
+	default:
+		return nil, fmt.Errorf("mustFirst: unable to find first element on type %s", tp)
+	}
+}

expression_test.go

@@ -1,6 +1,7 @@
 package skipper_test
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -59,14 +60,62 @@ func TestExpressionManager_ExecuteInput(t *testing.T) {
 		errExpected error
 	}{
 		{
-			name:  "ExpressionManager_ExecuteInput",
-			input: "${john:name}",
+			name:  "Simple valid path",
+			input: "This is ${project:name}",
 			pathValues: map[string]data.Value{
-				"john.name":  data.NewValue("${john:first} ${john:last}"),
+				"project.name": data.NewValue("skipper"),
+			},
+			expected: data.NewValue("This is skipper"),
+		},
+		{
+			name:  "Simple path with dependencies",
+			input: "Hello there, ${john:name}",
+			pathValues: map[string]data.Value{
+				"john.name":  data.NewValue("${to_upper(john:first)} ${to_lower(john:last)}"),
 				"john.first": data.NewValue("john"),
 				"john.last":  data.NewValue("doe"),
 			},
-			expected: data.NewValue("john doe"),
+			expected: data.NewValue("Hello there, JOHN doe"),
+		},
+		{
+			name:  "Function call",
+			input: "This is ${to_upper(project:name)}",
+			pathValues: map[string]data.Value{
+				"project.name": data.NewValue("skipper"),
+			},
+			expected: data.NewValue("This is SKIPPER"),
+		},
+		{
+			name:  "Function call with two params",
+			input: `This is ${replace(project:name, "skipper", "peter")}`,
+			pathValues: map[string]data.Value{
+				"project.name": data.NewValue("skipper"),
+			},
+			expected: data.NewValue("This is peter"),
+		},
+		{
+			name:  "List function call with valid string list",
+			input: `This is ${first(project:names)}`,
+			pathValues: map[string]data.Value{
+				"project.names": data.NewValue([]string{"skipper", "bob"}),
+			},
+			expected: data.NewValue("This is skipper"),
+		},
+		{
+			name:  "List function call with valid int list",
+			input: `This is ${first(project:names)}`,
+			pathValues: map[string]data.Value{
+				"project.names": data.NewValue([]int{1, 2, 3, 4}),
+			},
+			expected: data.NewValue("This is 1"),
+		},
+		{
+			name:  "List function call with invalid list",
+			input: `This is ${first(project:names)}`,
+			pathValues: map[string]data.Value{
+				"project.names": data.NewValue("def-not-a-list"),
+			},
+			errExpected: fmt.Errorf("failed to convert data.Value to list"),
 		},
 	}
 
@@ -89,7 +138,7 @@ func TestExpressionManager_ExecuteInput(t *testing.T) {
 			ret, err := exprManager.ExecuteInput(tt.input)
 
 			if tt.errExpected != nil {
-				assert.ErrorIs(t, err, tt.errExpected)
+				assert.ErrorContains(t, err, tt.errExpected.Error())
 				return
 			}
 

go.mod

@@ -1,6 +1,8 @@
 module github.com/lukasjarosch/skipper
 
-go 1.21
+go 1.22
+
+toolchain go1.22.0
 
 require (
 	github.com/dominikbraun/graph v0.23.0
@@ -11,8 +13,11 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/iancoleman/strcase v0.3.0 // indirect
-	github.com/kr/pretty v0.2.0 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/rogpeppe/go-internal v1.12.0 // indirect
+	github.com/ryboe/q v1.0.21 // indirect
 	github.com/stretchr/objx v0.5.0 // indirect
 	github.com/vektra/mockery v1.1.2 // indirect
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect

go.sum

@@ -1,3 +1,4 @@
+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -7,11 +8,21 @@ github.com/iancoleman/strcase v0.3.0 h1:nTXanmYxhfFAMjZL34Ov6gkzEsSJZ5DbhxWjvSAS
 github.com/iancoleman/strcase v0.3.0/go.mod h1:iwCmte+B7n89clKwxIoIXy/HfoL7AsD47ZCWhYzw7ho=
 github.com/kr/pretty v0.2.0 h1:s5hAObm+yFO5uHYt5dYjxi2rXrsnmRpJx4OYvIWUaQs=
 github.com/kr/pretty v0.2.0/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
+github.com/rogpeppe/go-internal v1.12.0 h1:exVL4IDcn6na9z1rAb56Vxr+CgyK3nn3O+epU5NdKM8=
+github.com/rogpeppe/go-internal v1.12.0/go.mod h1:E+RYuTGaKKdloAfM02xzb0FW3Paa99yedzYV+kq4uf4=
+github.com/ryboe/q v1.0.21 h1:sbLQFC3eMDEs8q3g4otbrWExLTHEyKISCFuN7Akropc=
+github.com/ryboe/q v1.0.21/go.mod h1:g4aI/DhdScxW3WLRGxHXgg5ZkGrk+b4h1h5u2PTCvDc=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=