1// Package core contains the target-agnostic code to define and run a bridge
2package core
3
4import (
5 "fmt"
6 "reflect"
7 "regexp"
8 "sort"
9 "strings"
10 "time"
11
12 "github.com/pkg/errors"
13
14 "github.com/MichaelMure/git-bug/cache"
15 "github.com/MichaelMure/git-bug/repository"
16)
17
18var ErrImportNotSupported = errors.New("import is not supported")
19var ErrExportNotSupported = errors.New("export is not supported")
20
21const (
22 keyTarget = "target"
23 bridgeConfigKeyPrefix = "git-bug.bridge"
24)
25
26var bridgeImpl map[string]reflect.Type
27
28// BridgeParams holds parameters to simplify the bridge configuration without
29// having to make terminal prompts.
30type BridgeParams struct {
31 Owner string
32 Project string
33 URL string
34 Token string
35}
36
37// Bridge is a wrapper around a BridgeImpl that will bind low-level
38// implementation with utility code to provide high-level functions.
39type Bridge struct {
40 Name string
41 repo *cache.RepoCache
42 impl BridgeImpl
43 importer Importer
44 exporter Exporter
45 conf Configuration
46 initDone bool
47}
48
49// Register will register a new BridgeImpl
50func Register(impl BridgeImpl) {
51 if bridgeImpl == nil {
52 bridgeImpl = make(map[string]reflect.Type)
53 }
54 bridgeImpl[impl.Target()] = reflect.TypeOf(impl)
55}
56
57// Targets return all known bridge implementation target
58func Targets() []string {
59 var result []string
60
61 for key := range bridgeImpl {
62 result = append(result, key)
63 }
64
65 sort.Strings(result)
66
67 return result
68}
69
70// Instantiate a new Bridge for a repo, from the given target and name
71func NewBridge(repo *cache.RepoCache, target string, name string) (*Bridge, error) {
72 implType, ok := bridgeImpl[target]
73 if !ok {
74 return nil, fmt.Errorf("unknown bridge target %v", target)
75 }
76
77 impl := reflect.New(implType).Elem().Interface().(BridgeImpl)
78
79 bridge := &Bridge{
80 Name: name,
81 repo: repo,
82 impl: impl,
83 }
84
85 return bridge, nil
86}
87
88// LoadBridge instantiate a new bridge from a repo configuration
89func LoadBridge(repo *cache.RepoCache, name string) (*Bridge, error) {
90 bridge := &Bridge{
91 Name: name,
92 repo: repo,
93 }
94
95 conf, err := bridge.loadConfig()
96 if err != nil {
97 return nil, err
98 }
99 bridge.conf = conf
100
101 target := bridge.conf[keyTarget]
102 implType, ok := bridgeImpl[target]
103 if !ok {
104 return nil, fmt.Errorf("unknown bridge target %v", target)
105 }
106
107 bridge.impl = reflect.New(implType).Elem().Interface().(BridgeImpl)
108
109 err = bridge.impl.ValidateConfig(bridge.conf)
110 if err != nil {
111 return nil, errors.Wrap(err, "invalid configuration")
112 }
113
114 return bridge, nil
115}
116
117// Attempt to retrieve a default bridge for the given repo. If zero or multiple
118// bridge exist, it fails.
119func DefaultBridge(repo *cache.RepoCache) (*Bridge, error) {
120 bridges, err := ConfiguredBridges(repo)
121 if err != nil {
122 return nil, err
123 }
124
125 if len(bridges) == 0 {
126 return nil, fmt.Errorf("no configured bridge")
127 }
128
129 if len(bridges) > 1 {
130 return nil, fmt.Errorf("multiple bridge are configured, you need to select one explicitely")
131 }
132
133 return LoadBridge(repo, bridges[0])
134}
135
136// ConfiguredBridges return the list of bridge that are configured for the given
137// repo
138func ConfiguredBridges(repo repository.RepoCommon) ([]string, error) {
139 configs, err := repo.ReadConfigs(bridgeConfigKeyPrefix + ".")
140 if err != nil {
141 return nil, errors.Wrap(err, "can't read configured bridges")
142 }
143
144 re, err := regexp.Compile(bridgeConfigKeyPrefix + `.([^.]+)`)
145 if err != nil {
146 panic(err)
147 }
148
149 set := make(map[string]interface{})
150
151 for key := range configs {
152 res := re.FindStringSubmatch(key)
153
154 if res == nil {
155 continue
156 }
157
158 set[res[1]] = nil
159 }
160
161 result := make([]string, len(set))
162
163 i := 0
164 for key := range set {
165 result[i] = key
166 i++
167 }
168
169 return result, nil
170}
171
172// Remove a configured bridge
173func RemoveBridge(repo repository.RepoCommon, name string) error {
174 re, err := regexp.Compile(`^[a-zA-Z0-9]+`)
175 if err != nil {
176 panic(err)
177 }
178
179 if !re.MatchString(name) {
180 return fmt.Errorf("bad bridge fullname: %s", name)
181 }
182
183 keyPrefix := fmt.Sprintf("git-bug.bridge.%s", name)
184 return repo.RmConfigs(keyPrefix)
185}
186
187// Configure run the target specific configuration process
188func (b *Bridge) Configure(params BridgeParams) error {
189 conf, err := b.impl.Configure(b.repo, params)
190 if err != nil {
191 return err
192 }
193
194 err = b.impl.ValidateConfig(conf)
195 if err != nil {
196 return fmt.Errorf("invalid configuration: %v", err)
197 }
198
199 b.conf = conf
200 return b.storeConfig(conf)
201}
202
203func (b *Bridge) storeConfig(conf Configuration) error {
204 for key, val := range conf {
205 storeKey := fmt.Sprintf("git-bug.bridge.%s.%s", b.Name, key)
206
207 err := b.repo.StoreConfig(storeKey, val)
208 if err != nil {
209 return errors.Wrap(err, "error while storing bridge configuration")
210 }
211 }
212
213 return nil
214}
215
216func (b *Bridge) ensureConfig() error {
217 if b.conf == nil {
218 conf, err := b.loadConfig()
219 if err != nil {
220 return err
221 }
222 b.conf = conf
223 }
224
225 return nil
226}
227
228func (b *Bridge) loadConfig() (Configuration, error) {
229 keyPrefix := fmt.Sprintf("git-bug.bridge.%s.", b.Name)
230
231 pairs, err := b.repo.ReadConfigs(keyPrefix)
232 if err != nil {
233 return nil, errors.Wrap(err, "error while reading bridge configuration")
234 }
235
236 result := make(Configuration, len(pairs))
237 for key, value := range pairs {
238 key := strings.TrimPrefix(key, keyPrefix)
239 result[key] = value
240 }
241
242 return result, nil
243}
244
245func (b *Bridge) getImporter() Importer {
246 if b.importer == nil {
247 b.importer = b.impl.NewImporter()
248 }
249
250 return b.importer
251}
252
253func (b *Bridge) getExporter() Exporter {
254 if b.exporter == nil {
255 b.exporter = b.impl.NewExporter()
256 }
257
258 return b.exporter
259}
260
261func (b *Bridge) ensureInit() error {
262 if b.initDone {
263 return nil
264 }
265
266 importer := b.getImporter()
267 if importer != nil {
268 err := importer.Init(b.conf)
269 if err != nil {
270 return err
271 }
272 }
273
274 exporter := b.getExporter()
275 if exporter != nil {
276 err := exporter.Init(b.conf)
277 if err != nil {
278 return err
279 }
280 }
281
282 b.initDone = true
283
284 return nil
285}
286
287func (b *Bridge) ImportAll(since time.Time) error {
288 importer := b.getImporter()
289 if importer == nil {
290 return ErrImportNotSupported
291 }
292
293 err := b.ensureConfig()
294 if err != nil {
295 return err
296 }
297
298 err = b.ensureInit()
299 if err != nil {
300 return err
301 }
302
303 return importer.ImportAll(b.repo, since)
304}
305
306func (b *Bridge) ExportAll(since time.Time) error {
307 exporter := b.getExporter()
308 if exporter == nil {
309 return ErrExportNotSupported
310 }
311
312 err := b.ensureConfig()
313 if err != nil {
314 return err
315 }
316
317 err = b.ensureInit()
318 if err != nil {
319 return err
320 }
321
322 return exporter.ExportAll(b.repo, since)
323}