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Integrate BACKBEAT SDK and resolve KACHING license validation

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Major integrations and fixes:
- Added BACKBEAT SDK integration for P2P operation timing
- Implemented beat-aware status tracking for distributed operations
- Added Docker secrets support for secure license management
- Resolved KACHING license validation via HTTPS/TLS
- Updated docker-compose configuration for clean stack deployment
- Disabled rollback policies to prevent deployment failures
- Added license credential storage (CHORUS-DEV-MULTI-001)

Technical improvements:
- BACKBEAT P2P operation tracking with phase management
- Enhanced configuration system with file-based secrets
- Improved error handling for license validation
- Clean separation of KACHING and CHORUS deployment stacks

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>
This commit is contained in:
anthonyrawlins
2025-09-06 07:56:26 +10:00
parent 543ab216f9
commit 9bdcbe0447
4730 changed files with 1480093 additions and 1916 deletions
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34
vendor/go.uber.org/dig/internal/digerror/errors.go generated vendored Normal file
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// Copyright (c) 2021 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package digerror
import (
"fmt"
)
// BugPanicf panics with the provided message directing users to GitHub issues
// creation page.
func BugPanicf(msg string, args ...interface{}) {
panic(fmt.Sprintf("It looks like you have found a bug in dig. "+
"Please file an issue at https://github.com/uber-go/dig/issues/new "+
"and provide the following message: "+
msg, args...))
}

125
vendor/go.uber.org/dig/internal/digreflect/func.go generated vendored Normal file
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// Copyright (c) 2019 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package digreflect
import (
"fmt"
"net/url"
"reflect"
"runtime"
"strings"
)
// Func contains runtime information about a function.
type Func struct {
// Name of the function.
Name string
// Name of the package in which this function is defined.
Package string
// Path to the file in which this function is defined.
File string
// Line number in the file at which this function is defined.
Line int
}
// String returns a string representation of the function.
func (f *Func) String() string {
return fmt.Sprint(f)
}
// Format implements fmt.Formatter for Func, printing a single-line
// representation for %v and a multi-line one for %+v.
func (f *Func) Format(w fmt.State, c rune) {
if w.Flag('+') && c == 'v' {
// "path/to/package".MyFunction
// path/to/file.go:42
fmt.Fprintf(w, "%q.%v", f.Package, f.Name)
fmt.Fprintf(w, "\n\t%v:%v", f.File, f.Line)
} else {
// "path/to/package".MyFunction (path/to/file.go:42)
fmt.Fprintf(w, "%q.%v (%v:%v)", f.Package, f.Name, f.File, f.Line)
}
}
// InspectFunc inspects and returns runtime information about the given
// function.
func InspectFunc(function interface{}) *Func {
fptr := reflect.ValueOf(function).Pointer()
return InspectFuncPC(fptr)
}
// InspectFuncPC inspects and returns runtime information about the function
// at the given program counter address.
func InspectFuncPC(pc uintptr) *Func {
f := runtime.FuncForPC(pc)
if f == nil {
return nil
}
pkgName, funcName := splitFuncName(f.Name())
fileName, lineNum := f.FileLine(pc)
return &Func{
Name: funcName,
Package: pkgName,
File: fileName,
Line: lineNum,
}
}
const _vendor = "/vendor/"
func splitFuncName(function string) (pname string, fname string) {
if len(function) == 0 {
return
}
// We have something like "path.to/my/pkg.MyFunction". If the function is
// a closure, it is something like, "path.to/my/pkg.MyFunction.func1".
idx := 0
// Everything up to the first "." after the last "/" is the package name.
// Everything after the "." is the full function name.
if i := strings.LastIndex(function, "/"); i >= 0 {
idx = i
}
if i := strings.Index(function[idx:], "."); i >= 0 {
idx += i
}
pname, fname = function[:idx], function[idx+1:]
// The package may be vendored.
if i := strings.Index(pname, _vendor); i > 0 {
pname = pname[i+len(_vendor):]
}
// Package names are URL-encoded to avoid ambiguity in the case where the
// package name contains ".git". Otherwise, "foo/bar.git.MyFunction" would
// mean that "git" is the top-level function and "MyFunction" is embedded
// inside it.
if unescaped, err := url.QueryUnescape(pname); err == nil {
pname = unescaped
}
return
}

61
vendor/go.uber.org/dig/internal/dot/README.md generated vendored Normal file
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# Dot
The dot module generates a DOT file representation of a dependency graph.
## Interpreting the graph
The graph should be read from left to right. The leftmost node in the graph (the root node) depends
on its dependency tree to the right. An arrow from node_a to node_b in the graph means that node_b
is consumed by node_a and that node_b is a parameter of node_a. The rendered graph holds the
following kinds of nodes,
**Nodes:**
- *Constructors* [Rectangles]: Takes parameters and produces results.
- *Results* [Ovals]: Results inside a constructor are produced by that constructor. Results are consumed
directly by other constructors and/or part of a group of results.
- *Groups* [Diamonds]: Represent value groups in [fx](https://godoc.org/go.uber.org/fx). Multiple results can form a group. Any
result linked to a group by an edge are members of that group. A group is a collection of results.
Groups can also be parameters of constructors.
**Edges:**
- *Solid Arrows*: An arrow from node_a to node_b means that node_b is a parameter of node_a and that
node_a depends on node_b.
- *Dashed Arrows*: A dashed arrow from node_a to node_b represents an optional dependency that node_a
has on node_b.
**Graph Colors:**
- *Red*: Graph nodes are the root cause failures.
- *Orange*: Graph nodes are the transitive failures.
## Testing and verifying changes
Unit tests and visualize golden tests are run with
```shell
$ make test
```
You can visualize the effect of your code changes by visualizing generated test graphs as pngs.
In the dig root directory, generate the graph DOT files with respect to your latest code changes.
```shell
$ go test -generate
```
Assuming that you have [graphviz](https://www.graphviz.org/) installed and are in the testdata directory,
generate a png image representation of a graph for viewing.
```shell
$ dot -Tpng ${name_of_dot_file_in_testdata}.dot -o ${name_of_dot_file_in_testdata}.png
$ open ${name_of_dot_file_in_testdata}.png
```
## Graph Pruning
If dot.Visualize is used to visualize an error graph, non-failing nodes are pruned out of the graph
to make the error graph more readable to the user. Pruning increases readability since successful
nodes clutter the graph and do not help the user debug errors.

466
vendor/go.uber.org/dig/internal/dot/graph.go generated vendored Normal file
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// Copyright (c) 2019 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package dot
import (
"fmt"
"reflect"
)
// ErrorType of a constructor or group is updated when they fail to build.
type ErrorType int
const (
noError ErrorType = iota
rootCause
transitiveFailure
)
// CtorID is a unique numeric identifier for constructors.
type CtorID uintptr
// Ctor encodes a constructor provided to the container for the DOT graph.
type Ctor struct {
Name string
Package string
File string
Line int
ID CtorID
Params []*Param
GroupParams []*Group
Results []*Result
ErrorType ErrorType
}
// removeParam deletes the dependency on the provided result's nodeKey.
// This is used to prune links to results of deleted constructors.
func (c *Ctor) removeParam(k nodeKey) {
var pruned []*Param
for _, p := range c.Params {
if k != p.nodeKey() {
pruned = append(pruned, p)
}
}
c.Params = pruned
}
type nodeKey struct {
t reflect.Type
name string
group string
}
// Node is a single node in a graph and is embedded into Params and Results.
type Node struct {
Type reflect.Type
Name string
Group string
}
func (n *Node) nodeKey() nodeKey {
return nodeKey{t: n.Type, name: n.Name, group: n.Group}
}
// Param is a parameter node in the graph. Parameters are the input to constructors.
type Param struct {
*Node
Optional bool
}
// Result is a result node in the graph. Results are the output of constructors.
type Result struct {
*Node
// GroupIndex is added to differentiate grouped values from one another.
// Since grouped values have the same type and group, their Node / string
// representations are the same so we need indices to uniquely identify
// the values.
GroupIndex int
}
// Group is a group node in the graph. Group represents an fx value group.
type Group struct {
// Type is the type of values in the group.
Type reflect.Type
Name string
Results []*Result
ErrorType ErrorType
}
func (g *Group) nodeKey() nodeKey {
return nodeKey{t: g.Type, group: g.Name}
}
// TODO(rhang): Avoid linear search to discover group results that should be pruned.
func (g *Group) removeResult(r *Result) {
var pruned []*Result
for _, rg := range g.Results {
if r.GroupIndex != rg.GroupIndex {
pruned = append(pruned, rg)
}
}
g.Results = pruned
}
// Graph is the DOT-format graph in a Container.
type Graph struct {
Ctors []*Ctor
ctorMap map[CtorID]*Ctor
Groups []*Group
groupMap map[nodeKey]*Group
consumers map[nodeKey][]*Ctor
Failed *FailedNodes
}
// FailedNodes is the nodes that failed in the graph.
type FailedNodes struct {
// RootCauses is a list of the point of failures. They are the root causes
// of failed invokes and can be either missing types (not provided) or
// error types (error providing).
RootCauses []*Result
// TransitiveFailures is the list of nodes that failed to build due to
// missing/failed dependencies.
TransitiveFailures []*Result
// ctors is a collection of failed constructors IDs that are populated as the graph is
// traversed for errors.
ctors map[CtorID]struct{}
// Groups is a collection of failed groupKeys that is populated as the graph is traversed
// for errors.
groups map[nodeKey]struct{}
}
// NewGraph creates an empty graph.
func NewGraph() *Graph {
return &Graph{
ctorMap: make(map[CtorID]*Ctor),
groupMap: make(map[nodeKey]*Group),
consumers: make(map[nodeKey][]*Ctor),
Failed: &FailedNodes{
ctors: make(map[CtorID]struct{}),
groups: make(map[nodeKey]struct{}),
},
}
}
// NewGroup creates a new group with information in the groupKey.
func NewGroup(k nodeKey) *Group {
return &Group{
Type: k.t,
Name: k.group,
}
}
// AddCtor adds the constructor with paramList and resultList into the graph.
func (dg *Graph) AddCtor(c *Ctor, paramList []*Param, resultList []*Result) {
var (
params []*Param
groupParams []*Group
)
// Loop through the paramList to separate them into regular params and
// grouped params. For grouped params, we use getGroup to find the actual
// group.
for _, param := range paramList {
if param.Group == "" {
// Not a value group.
params = append(params, param)
continue
}
k := nodeKey{t: param.Type.Elem(), group: param.Group}
group := dg.getGroup(k)
groupParams = append(groupParams, group)
}
for _, result := range resultList {
// If the result is a grouped value, we want to update its GroupIndex
// and add it to the Group.
if result.Group != "" {
dg.addToGroup(result, c.ID)
}
}
c.Params = params
c.GroupParams = groupParams
c.Results = resultList
// Track which constructors consume a parameter.
for _, p := range paramList {
k := p.nodeKey()
dg.consumers[k] = append(dg.consumers[k], c)
}
dg.Ctors = append(dg.Ctors, c)
dg.ctorMap[c.ID] = c
}
func (dg *Graph) failNode(r *Result, isRootCause bool) {
if isRootCause {
dg.addRootCause(r)
} else {
dg.addTransitiveFailure(r)
}
}
// AddMissingNodes adds missing nodes to the list of failed Results in the graph.
func (dg *Graph) AddMissingNodes(results []*Result) {
// The failure(s) are root causes if there are no other failures.
isRootCause := len(dg.Failed.RootCauses) == 0
for _, r := range results {
dg.failNode(r, isRootCause)
}
}
// FailNodes adds results to the list of failed Results in the graph, and
// updates the state of the constructor with the given id accordingly.
func (dg *Graph) FailNodes(results []*Result, id CtorID) {
// This failure is the root cause if there are no other failures.
isRootCause := len(dg.Failed.RootCauses) == 0
dg.Failed.ctors[id] = struct{}{}
for _, r := range results {
dg.failNode(r, isRootCause)
}
if c, ok := dg.ctorMap[id]; ok {
if isRootCause {
c.ErrorType = rootCause
} else {
c.ErrorType = transitiveFailure
}
}
}
// FailGroupNodes finds and adds the failed grouped nodes to the list of failed
// Results in the graph, and updates the state of the group and constructor
// with the given id accordingly.
func (dg *Graph) FailGroupNodes(name string, t reflect.Type, id CtorID) {
// This failure is the root cause if there are no other failures.
isRootCause := len(dg.Failed.RootCauses) == 0
k := nodeKey{t: t, group: name}
group := dg.getGroup(k)
// If the ctor does not exist it cannot be failed.
if _, ok := dg.ctorMap[id]; !ok {
return
}
// Track which constructors and groups have failed.
dg.Failed.ctors[id] = struct{}{}
dg.Failed.groups[k] = struct{}{}
for _, r := range dg.ctorMap[id].Results {
if r.Type == t && r.Group == name {
dg.failNode(r, isRootCause)
}
}
if c, ok := dg.ctorMap[id]; ok {
if isRootCause {
group.ErrorType = rootCause
c.ErrorType = rootCause
} else {
group.ErrorType = transitiveFailure
c.ErrorType = transitiveFailure
}
}
}
// getGroup finds the group by nodeKey from the graph. If it is not available,
// a new group is created and returned.
func (dg *Graph) getGroup(k nodeKey) *Group {
g, ok := dg.groupMap[k]
if !ok {
g = NewGroup(k)
dg.groupMap[k] = g
dg.Groups = append(dg.Groups, g)
}
return g
}
// addToGroup adds a newly provided grouped result to the appropriate group.
func (dg *Graph) addToGroup(r *Result, id CtorID) {
k := nodeKey{t: r.Type, group: r.Group}
group := dg.getGroup(k)
r.GroupIndex = len(group.Results)
group.Results = append(group.Results, r)
}
// PruneSuccess removes elements from the graph that do not have failed results.
// Removing elements that do not have failing results makes the graph easier to debug,
// since non-failing nodes and edges can clutter the graph and don't help the user debug.
func (dg *Graph) PruneSuccess() {
dg.pruneCtors(dg.Failed.ctors)
dg.pruneGroups(dg.Failed.groups)
}
// pruneCtors removes constructors from the graph that do not have failing Results.
func (dg *Graph) pruneCtors(failed map[CtorID]struct{}) {
var pruned []*Ctor
for _, c := range dg.Ctors {
if _, ok := failed[c.ID]; ok {
pruned = append(pruned, c)
continue
}
// If a constructor is deleted, the constructor's stale result references need to
// be removed from that result's Group and/or consuming constructor.
dg.pruneCtorParams(c, dg.consumers)
dg.pruneGroupResults(c, dg.groupMap)
delete(dg.ctorMap, c.ID)
}
dg.Ctors = pruned
}
// pruneGroups removes groups from the graph that do not have failing results.
func (dg *Graph) pruneGroups(failed map[nodeKey]struct{}) {
var pruned []*Group
for _, g := range dg.Groups {
k := g.nodeKey()
if _, ok := failed[k]; ok {
pruned = append(pruned, g)
continue
}
delete(dg.groupMap, k)
}
dg.Groups = pruned
dg.pruneCtorGroupParams(dg.groupMap)
}
// pruneCtorParams removes results of the constructor argument that are still referenced in the
// Params of constructors that consume those results. If the results in the constructor are found
// in the params of a consuming constructor that result should be removed.
func (dg *Graph) pruneCtorParams(c *Ctor, consumers map[nodeKey][]*Ctor) {
for _, r := range c.Results {
for _, ctor := range consumers[r.nodeKey()] {
ctor.removeParam(r.nodeKey())
}
}
}
// pruneCtorGroupParams removes constructor results that are still referenced in the GroupParams of
// constructors that consume those results.
func (dg *Graph) pruneCtorGroupParams(groups map[nodeKey]*Group) {
for _, c := range dg.Ctors {
var pruned []*Group
for _, gp := range c.GroupParams {
k := gp.nodeKey()
if _, ok := groups[k]; ok {
pruned = append(pruned, gp)
}
}
c.GroupParams = pruned
}
}
// pruneGroupResults removes results of the constructor argument that are still referenced in
// the Group object that contains that result. If a group no longer exists references to that
// should should be removed.
func (dg *Graph) pruneGroupResults(c *Ctor, groups map[nodeKey]*Group) {
for _, r := range c.Results {
k := r.nodeKey()
if k.group == "" {
continue
}
g, ok := groups[k]
if ok {
g.removeResult(r)
}
}
}
// String implements fmt.Stringer for Param.
func (p *Param) String() string {
if p.Name != "" {
return fmt.Sprintf("%v[name=%v]", p.Type.String(), p.Name)
}
return p.Type.String()
}
// String implements fmt.Stringer for Result.
func (r *Result) String() string {
switch {
case r.Name != "":
return fmt.Sprintf("%v[name=%v]", r.Type.String(), r.Name)
case r.Group != "":
return fmt.Sprintf("%v[group=%v]%v", r.Type.String(), r.Group, r.GroupIndex)
default:
return r.Type.String()
}
}
// String implements fmt.Stringer for Group.
func (g *Group) String() string {
return fmt.Sprintf("[type=%v group=%v]", g.Type.String(), g.Name)
}
// Attributes composes and returns a string of the Result node's attributes.
func (r *Result) Attributes() string {
switch {
case r.Name != "":
return fmt.Sprintf(`label=<%v<BR /><FONT POINT-SIZE="10">Name: %v</FONT>>`, r.Type, r.Name)
case r.Group != "":
return fmt.Sprintf(`label=<%v<BR /><FONT POINT-SIZE="10">Group: %v</FONT>>`, r.Type, r.Group)
default:
return fmt.Sprintf(`label=<%v>`, r.Type)
}
}
// Attributes composes and returns a string of the Group node's attributes.
func (g *Group) Attributes() string {
attr := fmt.Sprintf(`shape=diamond label=<%v<BR /><FONT POINT-SIZE="10">Group: %v</FONT>>`, g.Type, g.Name)
if g.ErrorType != noError {
attr += " color=" + g.ErrorType.Color()
}
return attr
}
// Color returns the color representation of each ErrorType.
func (s ErrorType) Color() string {
switch s {
case rootCause:
return "red"
case transitiveFailure:
return "orange"
default:
return "black"
}
}
func (dg *Graph) addRootCause(r *Result) {
dg.Failed.RootCauses = append(dg.Failed.RootCauses, r)
}
func (dg *Graph) addTransitiveFailure(r *Result) {
dg.Failed.TransitiveFailures = append(dg.Failed.TransitiveFailures, r)
}

118
vendor/go.uber.org/dig/internal/graph/graph.go generated vendored Normal file
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// Copyright (c) 2021 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package graph
// Graph represents a simple interface for representation
// of a directed graph.
// It is assumed that each node in the graph is uniquely
// identified with an incremental positive integer (i.e. 1, 2, 3...).
// A value of 0 for a node represents a sentinel error value.
type Graph interface {
// Order returns the total number of nodes in the graph
Order() int
// EdgesFrom returns a list of integers that each
// represents a node that has an edge from node u.
EdgesFrom(u int) []int
}
// IsAcyclic uses depth-first search to find cycles
// in a generic graph represented by Graph interface.
// If a cycle is found, it returns a list of nodes that
// are in the cyclic path, identified by their orders.
func IsAcyclic(g Graph) (bool, []int) {
// cycleStart is a node that introduces a cycle in
// the graph. Values in the range [1, g.Order()) mean
// that there exists a cycle in g.
info := newCycleInfo(g.Order())
for i := 0; i < g.Order(); i++ {
info.Reset()
cycle := isAcyclic(g, i, info, nil /* cycle path */)
if len(cycle) > 0 {
return false, cycle
}
}
return true, nil
}
// isAcyclic traverses the given graph starting from a specific node
// using depth-first search using recursion. If a cycle is detected,
// it returns the node that contains the "last" edge that introduces
// a cycle.
// For example, running isAcyclic starting from 1 on the following
// graph will return 3.
//
// 1 -> 2 -> 3 -> 1
func isAcyclic(g Graph, u int, info cycleInfo, path []int) []int {
// We've already verified that there are no cycles from this node.
if info[u].Visited {
return nil
}
info[u].Visited = true
info[u].OnStack = true
path = append(path, u)
for _, v := range g.EdgesFrom(u) {
if !info[v].Visited {
if cycle := isAcyclic(g, v, info, path); len(cycle) > 0 {
return cycle
}
} else if info[v].OnStack {
// We've found a cycle, and we have a full path back.
// Prune it down to just the cyclic nodes.
cycle := path
for i := len(cycle) - 1; i >= 0; i-- {
if cycle[i] == v {
cycle = cycle[i:]
break
}
}
// Complete the cycle by adding this node to it.
return append(cycle, v)
}
}
info[u].OnStack = false
return nil
}
// cycleNode keeps track of a single node's info for cycle detection.
type cycleNode struct {
Visited bool
OnStack bool
}
// cycleInfo contains information about each node while we're trying to find
// cycles.
type cycleInfo []cycleNode
func newCycleInfo(order int) cycleInfo {
return make(cycleInfo, order)
}
func (info cycleInfo) Reset() {
for i := range info {
info[i].OnStack = false
}
}