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-rw-r--r--vendor/github.com/googleapis/gax-go/CONTRIBUTING.md27
-rw-r--r--vendor/github.com/googleapis/gax-go/LICENSE27
-rw-r--r--vendor/github.com/googleapis/gax-go/README.md11
-rw-r--r--vendor/github.com/googleapis/gax-go/call_option.go136
-rw-r--r--vendor/github.com/googleapis/gax-go/gax.go32
-rw-r--r--vendor/github.com/googleapis/gax-go/invoke.go90
-rw-r--r--vendor/github.com/googleapis/gax-go/path_template.go176
-rw-r--r--vendor/github.com/googleapis/gax-go/path_template_parser.go227
8 files changed, 726 insertions, 0 deletions
diff --git a/vendor/github.com/googleapis/gax-go/CONTRIBUTING.md b/vendor/github.com/googleapis/gax-go/CONTRIBUTING.md
new file mode 100644
index 0000000..2827b7d
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/CONTRIBUTING.md
@@ -0,0 +1,27 @@
+Want to contribute? Great! First, read this page (including the small print at the end).
+
+### Before you contribute
+Before we can use your code, you must sign the
+[Google Individual Contributor License Agreement]
+(https://cla.developers.google.com/about/google-individual)
+(CLA), which you can do online. The CLA is necessary mainly because you own the
+copyright to your changes, even after your contribution becomes part of our
+codebase, so we need your permission to use and distribute your code. We also
+need to be sure of various other things—for instance that you'll tell us if you
+know that your code infringes on other people's patents. You don't have to sign
+the CLA until after you've submitted your code for review and a member has
+approved it, but you must do it before we can put your code into our codebase.
+Before you start working on a larger contribution, you should get in touch with
+us first through the issue tracker with your idea so that we can help out and
+possibly guide you. Coordinating up front makes it much easier to avoid
+frustration later on.
+
+### Code reviews
+All submissions, including submissions by project members, require review. We
+use Github pull requests for this purpose.
+
+### The small print
+Contributions made by corporations are covered by a different agreement than
+the one above, the
+[Software Grant and Corporate Contributor License Agreement]
+(https://cla.developers.google.com/about/google-corporate).
diff --git a/vendor/github.com/googleapis/gax-go/LICENSE b/vendor/github.com/googleapis/gax-go/LICENSE
new file mode 100644
index 0000000..6d16b65
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/LICENSE
@@ -0,0 +1,27 @@
+Copyright 2016, Google Inc.
+All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+ * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/googleapis/gax-go/README.md b/vendor/github.com/googleapis/gax-go/README.md
new file mode 100644
index 0000000..38ebdcf
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/README.md
@@ -0,0 +1,11 @@
+Google API Extensions for Go
+============================
+
+[![Build Status](https://travis-ci.org/googleapis/gax-go.svg?branch=master)](https://travis-ci.org/googleapis/gax-go)
+[![Code Coverage](https://img.shields.io/codecov/c/github/googleapis/gax-go.svg)](https://codecov.io/github/googleapis/gax-go)
+
+Google API Extensions for Go (gax-go) is a set of modules which aids the
+development of APIs for clients and servers based on `gRPC` and Google API
+conventions.
+
+This project is currently experimental and not supported.
diff --git a/vendor/github.com/googleapis/gax-go/call_option.go b/vendor/github.com/googleapis/gax-go/call_option.go
new file mode 100644
index 0000000..4ba1cdf
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/call_option.go
@@ -0,0 +1,136 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+import (
+ "math/rand"
+ "time"
+
+ "google.golang.org/grpc"
+ "google.golang.org/grpc/codes"
+)
+
+// CallOption is an option used by Invoke to control behaviors of RPC calls.
+// CallOption works by modifying relevant fields of CallSettings.
+type CallOption interface {
+ // Resolve applies the option by modifying cs.
+ Resolve(cs *CallSettings)
+}
+
+// Retryer is used by Invoke to determine retry behavior.
+type Retryer interface {
+ // Retry reports whether a request should be retriedand how long to pause before retrying
+ // if the previous attempt returned with err. Invoke never calls Retry with nil error.
+ Retry(err error) (pause time.Duration, shouldRetry bool)
+}
+
+type retryerOption func() Retryer
+
+func (o retryerOption) Resolve(s *CallSettings) {
+ s.Retry = o
+}
+
+// WithRetry sets CallSettings.Retry to fn.
+func WithRetry(fn func() Retryer) CallOption {
+ return retryerOption(fn)
+}
+
+// OnCodes returns a Retryer that retries if and only if
+// the previous attempt returns a GRPC error whose error code is stored in cc.
+// Pause times between retries are specified by bo.
+//
+// bo is only used for its parameters; each Retryer has its own copy.
+func OnCodes(cc []codes.Code, bo Backoff) Retryer {
+ return &boRetryer{
+ backoff: bo,
+ codes: append([]codes.Code(nil), cc...),
+ }
+}
+
+type boRetryer struct {
+ backoff Backoff
+ codes []codes.Code
+}
+
+func (r *boRetryer) Retry(err error) (time.Duration, bool) {
+ c := grpc.Code(err)
+ for _, rc := range r.codes {
+ if c == rc {
+ return r.backoff.Pause(), true
+ }
+ }
+ return 0, false
+}
+
+// Backoff implements exponential backoff.
+// The wait time between retries is a random value between 0 and the "retry envelope".
+// The envelope starts at Initial and increases by the factor of Multiplier every retry,
+// but is capped at Max.
+type Backoff struct {
+ // Initial is the initial value of the retry envelope, defaults to 1 second.
+ Initial time.Duration
+
+ // Max is the maximum value of the retry envelope, defaults to 30 seconds.
+ Max time.Duration
+
+ // Multiplier is the factor by which the retry envelope increases.
+ // It should be greater than 1 and defaults to 2.
+ Multiplier float64
+
+ // cur is the current retry envelope
+ cur time.Duration
+}
+
+func (bo *Backoff) Pause() time.Duration {
+ if bo.Initial == 0 {
+ bo.Initial = time.Second
+ }
+ if bo.cur == 0 {
+ bo.cur = bo.Initial
+ }
+ if bo.Max == 0 {
+ bo.Max = 30 * time.Second
+ }
+ if bo.Multiplier < 1 {
+ bo.Multiplier = 2
+ }
+ d := time.Duration(rand.Int63n(int64(bo.cur)))
+ bo.cur = time.Duration(float64(bo.cur) * bo.Multiplier)
+ if bo.cur > bo.Max {
+ bo.cur = bo.Max
+ }
+ return d
+}
+
+type CallSettings struct {
+ // Retry returns a Retryer to be used to control retry logic of a method call.
+ // If Retry is nil or the returned Retryer is nil, the call will not be retried.
+ Retry func() Retryer
+}
diff --git a/vendor/github.com/googleapis/gax-go/gax.go b/vendor/github.com/googleapis/gax-go/gax.go
new file mode 100644
index 0000000..c7e4ce9
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/gax.go
@@ -0,0 +1,32 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+const Version = "0.1.0"
diff --git a/vendor/github.com/googleapis/gax-go/invoke.go b/vendor/github.com/googleapis/gax-go/invoke.go
new file mode 100644
index 0000000..d2134e1
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/invoke.go
@@ -0,0 +1,90 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+import (
+ "time"
+
+ "golang.org/x/net/context"
+)
+
+// A user defined call stub.
+type APICall func(context.Context) error
+
+// Invoke calls the given APICall,
+// performing retries as specified by opts, if any.
+func Invoke(ctx context.Context, call APICall, opts ...CallOption) error {
+ var settings CallSettings
+ for _, opt := range opts {
+ opt.Resolve(&settings)
+ }
+ return invoke(ctx, call, settings, Sleep)
+}
+
+// Sleep is similar to time.Sleep, but it can be interrupted by ctx.Done() closing.
+// If interrupted, Sleep returns ctx.Err().
+func Sleep(ctx context.Context, d time.Duration) error {
+ t := time.NewTimer(d)
+ select {
+ case <-ctx.Done():
+ t.Stop()
+ return ctx.Err()
+ case <-t.C:
+ return nil
+ }
+}
+
+type sleeper func(ctx context.Context, d time.Duration) error
+
+// invoke implements Invoke, taking an additional sleeper argument for testing.
+func invoke(ctx context.Context, call APICall, settings CallSettings, sp sleeper) error {
+ var retryer Retryer
+ for {
+ err := call(ctx)
+ if err == nil {
+ return nil
+ }
+ if settings.Retry == nil {
+ return err
+ }
+ if retryer == nil {
+ if r := settings.Retry(); r != nil {
+ retryer = r
+ } else {
+ return err
+ }
+ }
+ if d, ok := retryer.Retry(err); !ok {
+ return err
+ } else if err = sp(ctx, d); err != nil {
+ return err
+ }
+ }
+}
diff --git a/vendor/github.com/googleapis/gax-go/path_template.go b/vendor/github.com/googleapis/gax-go/path_template.go
new file mode 100644
index 0000000..41bda94
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/path_template.go
@@ -0,0 +1,176 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+import (
+ "errors"
+ "fmt"
+ "strings"
+)
+
+type matcher interface {
+ match([]string) (int, error)
+ String() string
+}
+
+type segment struct {
+ matcher
+ name string
+}
+
+type labelMatcher string
+
+func (ls labelMatcher) match(segments []string) (int, error) {
+ if len(segments) == 0 {
+ return 0, fmt.Errorf("expected %s but no more segments found", ls)
+ }
+ if segments[0] != string(ls) {
+ return 0, fmt.Errorf("expected %s but got %s", ls, segments[0])
+ }
+ return 1, nil
+}
+
+func (ls labelMatcher) String() string {
+ return string(ls)
+}
+
+type wildcardMatcher int
+
+func (wm wildcardMatcher) match(segments []string) (int, error) {
+ if len(segments) == 0 {
+ return 0, errors.New("no more segments found")
+ }
+ return 1, nil
+}
+
+func (wm wildcardMatcher) String() string {
+ return "*"
+}
+
+type pathWildcardMatcher int
+
+func (pwm pathWildcardMatcher) match(segments []string) (int, error) {
+ length := len(segments) - int(pwm)
+ if length <= 0 {
+ return 0, errors.New("not sufficient segments are supplied for path wildcard")
+ }
+ return length, nil
+}
+
+func (pwm pathWildcardMatcher) String() string {
+ return "**"
+}
+
+type ParseError struct {
+ Pos int
+ Template string
+ Message string
+}
+
+func (pe ParseError) Error() string {
+ return fmt.Sprintf("at %d of template '%s', %s", pe.Pos, pe.Template, pe.Message)
+}
+
+// PathTemplate manages the template to build and match with paths used
+// by API services. It holds a template and variable names in it, and
+// it can extract matched patterns from a path string or build a path
+// string from a binding.
+//
+// See http.proto in github.com/googleapis/googleapis/ for the details of
+// the template syntax.
+type PathTemplate struct {
+ segments []segment
+}
+
+// NewPathTemplate parses a path template, and returns a PathTemplate
+// instance if successful.
+func NewPathTemplate(template string) (*PathTemplate, error) {
+ return parsePathTemplate(template)
+}
+
+// MustCompilePathTemplate is like NewPathTemplate but panics if the
+// expression cannot be parsed. It simplifies safe initialization of
+// global variables holding compiled regular expressions.
+func MustCompilePathTemplate(template string) *PathTemplate {
+ pt, err := NewPathTemplate(template)
+ if err != nil {
+ panic(err)
+ }
+ return pt
+}
+
+// Match attempts to match the given path with the template, and returns
+// the mapping of the variable name to the matched pattern string.
+func (pt *PathTemplate) Match(path string) (map[string]string, error) {
+ paths := strings.Split(path, "/")
+ values := map[string]string{}
+ for _, segment := range pt.segments {
+ length, err := segment.match(paths)
+ if err != nil {
+ return nil, err
+ }
+ if segment.name != "" {
+ value := strings.Join(paths[:length], "/")
+ if oldValue, ok := values[segment.name]; ok {
+ values[segment.name] = oldValue + "/" + value
+ } else {
+ values[segment.name] = value
+ }
+ }
+ paths = paths[length:]
+ }
+ if len(paths) != 0 {
+ return nil, fmt.Errorf("Trailing path %s remains after the matching", strings.Join(paths, "/"))
+ }
+ return values, nil
+}
+
+// Render creates a path string from its template and the binding from
+// the variable name to the value.
+func (pt *PathTemplate) Render(binding map[string]string) (string, error) {
+ result := make([]string, 0, len(pt.segments))
+ var lastVariableName string
+ for _, segment := range pt.segments {
+ name := segment.name
+ if lastVariableName != "" && name == lastVariableName {
+ continue
+ }
+ lastVariableName = name
+ if name == "" {
+ result = append(result, segment.String())
+ } else if value, ok := binding[name]; ok {
+ result = append(result, value)
+ } else {
+ return "", fmt.Errorf("%s is not found", name)
+ }
+ }
+ built := strings.Join(result, "/")
+ return built, nil
+}
diff --git a/vendor/github.com/googleapis/gax-go/path_template_parser.go b/vendor/github.com/googleapis/gax-go/path_template_parser.go
new file mode 100644
index 0000000..79c8e75
--- /dev/null
+++ b/vendor/github.com/googleapis/gax-go/path_template_parser.go
@@ -0,0 +1,227 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package gax
+
+import (
+ "fmt"
+ "io"
+ "strings"
+)
+
+// This parser follows the syntax of path templates, from
+// https://github.com/googleapis/googleapis/blob/master/google/api/http.proto.
+// The differences are that there is no custom verb, we allow the initial slash
+// to be absent, and that we are not strict as
+// https://tools.ietf.org/html/rfc6570 about the characters in identifiers and
+// literals.
+
+type pathTemplateParser struct {
+ r *strings.Reader
+ runeCount int // the number of the current rune in the original string
+ nextVar int // the number to use for the next unnamed variable
+ seenName map[string]bool // names we've seen already
+ seenPathWildcard bool // have we seen "**" already?
+}
+
+func parsePathTemplate(template string) (pt *PathTemplate, err error) {
+ p := &pathTemplateParser{
+ r: strings.NewReader(template),
+ seenName: map[string]bool{},
+ }
+
+ // Handle panics with strings like errors.
+ // See pathTemplateParser.error, below.
+ defer func() {
+ if x := recover(); x != nil {
+ errmsg, ok := x.(errString)
+ if !ok {
+ panic(x)
+ }
+ pt = nil
+ err = ParseError{p.runeCount, template, string(errmsg)}
+ }
+ }()
+
+ segs := p.template()
+ // If there is a path wildcard, set its length. We can't do this
+ // until we know how many segments we've got all together.
+ for i, seg := range segs {
+ if _, ok := seg.matcher.(pathWildcardMatcher); ok {
+ segs[i].matcher = pathWildcardMatcher(len(segs) - i - 1)
+ break
+ }
+ }
+ return &PathTemplate{segments: segs}, nil
+
+}
+
+// Used to indicate errors "thrown" by this parser. We don't use string because
+// many parts of the standard library panic with strings.
+type errString string
+
+// Terminates parsing immediately with an error.
+func (p *pathTemplateParser) error(msg string) {
+ panic(errString(msg))
+}
+
+// Template = [ "/" ] Segments
+func (p *pathTemplateParser) template() []segment {
+ var segs []segment
+ if p.consume('/') {
+ // Initial '/' needs an initial empty matcher.
+ segs = append(segs, segment{matcher: labelMatcher("")})
+ }
+ return append(segs, p.segments("")...)
+}
+
+// Segments = Segment { "/" Segment }
+func (p *pathTemplateParser) segments(name string) []segment {
+ var segs []segment
+ for {
+ subsegs := p.segment(name)
+ segs = append(segs, subsegs...)
+ if !p.consume('/') {
+ break
+ }
+ }
+ return segs
+}
+
+// Segment = "*" | "**" | LITERAL | Variable
+func (p *pathTemplateParser) segment(name string) []segment {
+ if p.consume('*') {
+ if name == "" {
+ name = fmt.Sprintf("$%d", p.nextVar)
+ p.nextVar++
+ }
+ if p.consume('*') {
+ if p.seenPathWildcard {
+ p.error("multiple '**' disallowed")
+ }
+ p.seenPathWildcard = true
+ // We'll change 0 to the right number at the end.
+ return []segment{{name: name, matcher: pathWildcardMatcher(0)}}
+ }
+ return []segment{{name: name, matcher: wildcardMatcher(0)}}
+ }
+ if p.consume('{') {
+ if name != "" {
+ p.error("recursive named bindings are not allowed")
+ }
+ return p.variable()
+ }
+ return []segment{{name: name, matcher: labelMatcher(p.literal())}}
+}
+
+// Variable = "{" FieldPath [ "=" Segments ] "}"
+// "{" is already consumed.
+func (p *pathTemplateParser) variable() []segment {
+ // Simplification: treat FieldPath as LITERAL, instead of IDENT { '.' IDENT }
+ name := p.literal()
+ if p.seenName[name] {
+ p.error(name + " appears multiple times")
+ }
+ p.seenName[name] = true
+ var segs []segment
+ if p.consume('=') {
+ segs = p.segments(name)
+ } else {
+ // "{var}" is equivalent to "{var=*}"
+ segs = []segment{{name: name, matcher: wildcardMatcher(0)}}
+ }
+ if !p.consume('}') {
+ p.error("expected '}'")
+ }
+ return segs
+}
+
+// A literal is any sequence of characters other than a few special ones.
+// The list of stop characters is not quite the same as in the template RFC.
+func (p *pathTemplateParser) literal() string {
+ lit := p.consumeUntil("/*}{=")
+ if lit == "" {
+ p.error("empty literal")
+ }
+ return lit
+}
+
+// Read runes until EOF or one of the runes in stopRunes is encountered.
+// If the latter, unread the stop rune. Return the accumulated runes as a string.
+func (p *pathTemplateParser) consumeUntil(stopRunes string) string {
+ var runes []rune
+ for {
+ r, ok := p.readRune()
+ if !ok {
+ break
+ }
+ if strings.IndexRune(stopRunes, r) >= 0 {
+ p.unreadRune()
+ break
+ }
+ runes = append(runes, r)
+ }
+ return string(runes)
+}
+
+// If the next rune is r, consume it and return true.
+// Otherwise, leave the input unchanged and return false.
+func (p *pathTemplateParser) consume(r rune) bool {
+ rr, ok := p.readRune()
+ if !ok {
+ return false
+ }
+ if r == rr {
+ return true
+ }
+ p.unreadRune()
+ return false
+}
+
+// Read the next rune from the input. Return it.
+// The second return value is false at EOF.
+func (p *pathTemplateParser) readRune() (rune, bool) {
+ r, _, err := p.r.ReadRune()
+ if err == io.EOF {
+ return r, false
+ }
+ if err != nil {
+ p.error(err.Error())
+ }
+ p.runeCount++
+ return r, true
+}
+
+// Put the last rune that was read back on the input.
+func (p *pathTemplateParser) unreadRune() {
+ if err := p.r.UnreadRune(); err != nil {
+ p.error(err.Error())
+ }
+ p.runeCount--
+}