Adding upstream version 0.28.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tools/search/simple_field_resolver.go

@@ -0,0 +1,113 @@
+package search
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/pocketbase/dbx"
+	"github.com/pocketbase/pocketbase/tools/inflector"
+	"github.com/pocketbase/pocketbase/tools/list"
+)
+
+// ResolverResult defines a single FieldResolver.Resolve() successfully parsed result.
+type ResolverResult struct {
+	// Identifier is the plain SQL identifier/column that will be used
+	// in the final db expression as left or right operand.
+	Identifier string
+
+	// NoCoalesce instructs to not use COALESCE or NULL fallbacks
+	// when building the identifier expression.
+	NoCoalesce bool
+
+	// Params is a map with db placeholder->value pairs that will be added
+	// to the query when building both resolved operands/sides in a single expression.
+	Params dbx.Params
+
+	// MultiMatchSubQuery is an optional sub query expression that will be added
+	// in addition to the combined ResolverResult expression during build.
+	MultiMatchSubQuery dbx.Expression
+
+	// AfterBuild is an optional function that will be called after building
+	// and combining the result of both resolved operands/sides in a single expression.
+	AfterBuild func(expr dbx.Expression) dbx.Expression
+}
+
+// FieldResolver defines an interface for managing search fields.
+type FieldResolver interface {
+	// UpdateQuery allows to updated the provided db query based on the
+	// resolved search fields (eg. adding joins aliases, etc.).
+	//
+	// Called internally by `search.Provider` before executing the search request.
+	UpdateQuery(query *dbx.SelectQuery) error
+
+	// Resolve parses the provided field and returns a properly
+	// formatted db identifier (eg. NULL, quoted column, placeholder parameter, etc.).
+	Resolve(field string) (*ResolverResult, error)
+}
+
+// NewSimpleFieldResolver creates a new `SimpleFieldResolver` with the
+// provided `allowedFields`.
+//
+// Each `allowedFields` could be a plain string (eg. "name")
+// or a regexp pattern (eg. `^\w+[\w\.]*$`).
+func NewSimpleFieldResolver(allowedFields ...string) *SimpleFieldResolver {
+	return &SimpleFieldResolver{
+		allowedFields: allowedFields,
+	}
+}
+
+// SimpleFieldResolver defines a generic search resolver that allows
+// only its listed fields to be resolved and take part in a search query.
+//
+// If `allowedFields` are empty no fields filtering is applied.
+type SimpleFieldResolver struct {
+	allowedFields []string
+}
+
+// UpdateQuery implements `search.UpdateQuery` interface.
+func (r *SimpleFieldResolver) UpdateQuery(query *dbx.SelectQuery) error {
+	// nothing to update...
+	return nil
+}
+
+// Resolve implements `search.Resolve` interface.
+//
+// Returns error if `field` is not in `r.allowedFields`.
+func (r *SimpleFieldResolver) Resolve(field string) (*ResolverResult, error) {
+	if !list.ExistInSliceWithRegex(field, r.allowedFields) {
+		return nil, fmt.Errorf("failed to resolve field %q", field)
+	}
+
+	parts := strings.Split(field, ".")
+
+	// single regular field
+	if len(parts) == 1 {
+		return &ResolverResult{
+			Identifier: "[[" + inflector.Columnify(parts[0]) + "]]",
+		}, nil
+	}
+
+	// treat as json path
+	var jsonPath strings.Builder
+	jsonPath.WriteString("$")
+	for _, part := range parts[1:] {
+		if _, err := strconv.Atoi(part); err == nil {
+			jsonPath.WriteString("[")
+			jsonPath.WriteString(inflector.Columnify(part))
+			jsonPath.WriteString("]")
+		} else {
+			jsonPath.WriteString(".")
+			jsonPath.WriteString(inflector.Columnify(part))
+		}
+	}
+
+	return &ResolverResult{
+		NoCoalesce: true,
+		Identifier: fmt.Sprintf(
+			"JSON_EXTRACT([[%s]], '%s')",
+			inflector.Columnify(parts[0]),
+			jsonPath.String(),
+		),
+	}, nil
+}