add --jq option to run a json query against Jira service response json

vendor/github.com/savaki/jq/op.go

@@ -0,0 +1,83 @@
+// Copyright (c) 2016 Matt Ho <matt.ho@gmail.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package jq
+
+import (
+	"strings"
+
+	"github.com/savaki/jq/scanner"
+)
+
+// Op defines a single transformation to be applied to a []byte
+type Op interface {
+	Apply([]byte) ([]byte, error)
+}
+
+// OpFunc provides a convenient func type wrapper on Op
+type OpFunc func([]byte) ([]byte, error)
+
+// Apply executes the transformation defined by OpFunc
+func (fn OpFunc) Apply(in []byte) ([]byte, error) {
+	return fn(in)
+}
+
+// Dot extract the specific key from the map provided; to extract a nested value, use the Dot Op in conjunction with the
+// Chain Op
+func Dot(key string) OpFunc {
+	key = strings.TrimSpace(key)
+	if key == "" {
+		return func(in []byte) ([]byte, error) { return in, nil }
+	}
+
+	k := []byte(key)
+
+	return func(in []byte) ([]byte, error) {
+		return scanner.FindKey(in, 0, k)
+	}
+}
+
+// Chain executes a series of operations in the order provided
+func Chain(filters ...Op) OpFunc {
+	return func(in []byte) ([]byte, error) {
+		if filters == nil {
+			return in, nil
+		}
+
+		var err error
+		data := in
+		for _, filter := range filters {
+			data, err = filter.Apply(data)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		return data, nil
+	}
+}
+
+// Index extracts a specific element from the array provided
+func Index(index int) OpFunc {
+	return func(in []byte) ([]byte, error) {
+		return scanner.FindIndex(in, 0, index)
+	}
+}
+
+// Range extracts a selection of elements from the array provided, inclusive
+func Range(from, to int) OpFunc {
+	return func(in []byte) ([]byte, error) {
+		return scanner.FindRange(in, 0, from, to)
+	}
+}