1package github
2
3import (
4 "context"
5 "time"
6
7 "github.com/shurcooL/githubv4"
8)
9
10type indexer struct{ index int }
11
12type issueEditIterator struct {
13 index int
14 query issueEditQuery
15 variables map[string]interface{}
16}
17
18type commentEditIterator struct {
19 index int
20 query commentEditQuery
21 variables map[string]interface{}
22}
23
24type timelineIterator struct {
25 index int
26 query issueTimelineQuery
27 variables map[string]interface{}
28
29 issueEdit indexer
30 commentEdit indexer
31
32 // lastEndCursor cache the timeline end cursor for one iteration
33 lastEndCursor githubv4.String
34}
35
36type iterator struct {
37 // github graphql client
38 gc *githubv4.Client
39
40 // if since is given the iterator will query only the updated
41 // and created issues after this date
42 since time.Time
43
44 // number of timelines/userEditcontent/issueEdit to query
45 // at a time, more capacity = more used memory = less queries
46 // to make
47 capacity int
48
49 // shared context used for all graphql queries
50 ctx context.Context
51
52 // sticky error
53 err error
54
55 // timeline iterator
56 timeline timelineIterator
57
58 // issue edit iterator
59 issueEdit issueEditIterator
60
61 // comment edit iterator
62 commentEdit commentEditIterator
63}
64
65// NewIterator create and initialize a new iterator
66func NewIterator(ctx context.Context, capacity int, owner, project, token string, since time.Time) *iterator {
67 i := &iterator{
68 gc: buildClient(token),
69 since: since,
70 capacity: capacity,
71 ctx: ctx,
72 timeline: timelineIterator{
73 index: -1,
74 issueEdit: indexer{-1},
75 commentEdit: indexer{-1},
76 variables: map[string]interface{}{
77 "owner": githubv4.String(owner),
78 "name": githubv4.String(project),
79 },
80 },
81 commentEdit: commentEditIterator{
82 index: -1,
83 variables: map[string]interface{}{
84 "owner": githubv4.String(owner),
85 "name": githubv4.String(project),
86 },
87 },
88 issueEdit: issueEditIterator{
89 index: -1,
90 variables: map[string]interface{}{
91 "owner": githubv4.String(owner),
92 "name": githubv4.String(project),
93 },
94 },
95 }
96
97 i.initTimelineQueryVariables()
98 return i
99}
100
101// init issue timeline variables
102func (i *iterator) initTimelineQueryVariables() {
103 i.timeline.variables["issueFirst"] = githubv4.Int(1)
104 i.timeline.variables["issueAfter"] = (*githubv4.String)(nil)
105 i.timeline.variables["issueSince"] = githubv4.DateTime{Time: i.since}
106 i.timeline.variables["timelineFirst"] = githubv4.Int(i.capacity)
107 i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
108 // Fun fact, github provide the comment edition in reverse chronological
109 // order, because haha. Look at me, I'm dying of laughter.
110 i.timeline.variables["issueEditLast"] = githubv4.Int(i.capacity)
111 i.timeline.variables["issueEditBefore"] = (*githubv4.String)(nil)
112 i.timeline.variables["commentEditLast"] = githubv4.Int(i.capacity)
113 i.timeline.variables["commentEditBefore"] = (*githubv4.String)(nil)
114}
115
116// init issue edit variables
117func (i *iterator) initIssueEditQueryVariables() {
118 i.issueEdit.variables["issueFirst"] = githubv4.Int(1)
119 i.issueEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
120 i.issueEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
121 i.issueEdit.variables["issueEditLast"] = githubv4.Int(i.capacity)
122 i.issueEdit.variables["issueEditBefore"] = (*githubv4.String)(nil)
123}
124
125// init issue comment variables
126func (i *iterator) initCommentEditQueryVariables() {
127 i.commentEdit.variables["issueFirst"] = githubv4.Int(1)
128 i.commentEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
129 i.commentEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
130 i.commentEdit.variables["timelineFirst"] = githubv4.Int(1)
131 i.commentEdit.variables["timelineAfter"] = (*githubv4.String)(nil)
132 i.commentEdit.variables["commentEditLast"] = githubv4.Int(i.capacity)
133 i.commentEdit.variables["commentEditBefore"] = (*githubv4.String)(nil)
134}
135
136// reverse UserContentEdits arrays in both of the issue and
137// comment timelines
138func (i *iterator) reverseTimelineEditNodes() {
139 node := i.timeline.query.Repository.Issues.Nodes[0]
140 reverseEdits(node.UserContentEdits.Nodes)
141 for index, ce := range node.TimelineItems.Edges {
142 if ce.Node.Typename == "IssueComment" && len(node.TimelineItems.Edges) != 0 {
143 reverseEdits(node.TimelineItems.Edges[index].Node.IssueComment.UserContentEdits.Nodes)
144 }
145 }
146}
147
148// Error return last encountered error
149func (i *iterator) Error() error {
150 return i.err
151}
152
153func (i *iterator) queryIssue() bool {
154 ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
155 defer cancel()
156
157 if err := i.gc.Query(ctx, &i.timeline.query, i.timeline.variables); err != nil {
158 i.err = err
159 return false
160 }
161
162 issues := i.timeline.query.Repository.Issues.Nodes
163 if len(issues) == 0 {
164 return false
165 }
166
167 i.reverseTimelineEditNodes()
168 return true
169}
170
171// NextIssue try to query the next issue and return true. Only one issue is
172// queried at each call.
173func (i *iterator) NextIssue() bool {
174 if i.err != nil {
175 return false
176 }
177
178 // if $issueAfter variable is nil we can directly make the first query
179 if i.timeline.variables["issueAfter"] == (*githubv4.String)(nil) {
180 nextIssue := i.queryIssue()
181 // prevent from infinite loop by setting a non nil cursor
182 issues := i.timeline.query.Repository.Issues
183 i.timeline.variables["issueAfter"] = issues.PageInfo.EndCursor
184 return nextIssue
185 }
186
187 issues := i.timeline.query.Repository.Issues
188 if !issues.PageInfo.HasNextPage {
189 return false
190 }
191
192 // if we have more issues, query them
193 i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
194 i.timeline.index = -1
195
196 timelineEndCursor := issues.Nodes[0].TimelineItems.PageInfo.EndCursor
197 // store cursor for future use
198 i.timeline.lastEndCursor = timelineEndCursor
199
200 // query issue block
201 nextIssue := i.queryIssue()
202 i.timeline.variables["issueAfter"] = issues.PageInfo.EndCursor
203
204 return nextIssue
205}
206
207// IssueValue return the actual issue value
208func (i *iterator) IssueValue() issueTimeline {
209 issues := i.timeline.query.Repository.Issues
210 return issues.Nodes[0]
211}
212
213// NextTimelineItem return true if there is a next timeline item and increments the index by one.
214// It is used iterates over all the timeline items. Extra queries are made if it is necessary.
215func (i *iterator) NextTimelineItem() bool {
216 if i.err != nil {
217 return false
218 }
219
220 if i.ctx.Err() != nil {
221 return false
222 }
223
224 timelineItems := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
225 // after NextIssue call it's good to check wether we have some timelineItems items or not
226 if len(timelineItems.Edges) == 0 {
227 return false
228 }
229
230 if i.timeline.index < len(timelineItems.Edges)-1 {
231 i.timeline.index++
232 return true
233 }
234
235 if !timelineItems.PageInfo.HasNextPage {
236 return false
237 }
238
239 i.timeline.lastEndCursor = timelineItems.PageInfo.EndCursor
240
241 // more timelines, query them
242 i.timeline.variables["timelineAfter"] = timelineItems.PageInfo.EndCursor
243
244 ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
245 defer cancel()
246
247 if err := i.gc.Query(ctx, &i.timeline.query, i.timeline.variables); err != nil {
248 i.err = err
249 return false
250 }
251
252 timelineItems = i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
253 // (in case github returns something weird) just for safety: better return a false than a panic
254 if len(timelineItems.Edges) == 0 {
255 return false
256 }
257
258 i.reverseTimelineEditNodes()
259 i.timeline.index = 0
260 return true
261}
262
263// TimelineItemValue return the actual timeline item value
264func (i *iterator) TimelineItemValue() timelineItem {
265 timelineItems := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems
266 return timelineItems.Edges[i.timeline.index].Node
267}
268
269func (i *iterator) queryIssueEdit() bool {
270 ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
271 defer cancel()
272
273 if err := i.gc.Query(ctx, &i.issueEdit.query, i.issueEdit.variables); err != nil {
274 i.err = err
275 //i.timeline.issueEdit.index = -1
276 return false
277 }
278
279 issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
280 // reverse issue edits because github
281 reverseEdits(issueEdits.Nodes)
282
283 // this is not supposed to happen
284 if len(issueEdits.Nodes) == 0 {
285 i.timeline.issueEdit.index = -1
286 return false
287 }
288
289 i.issueEdit.index = 0
290 i.timeline.issueEdit.index = -2
291 return i.nextValidIssueEdit()
292}
293
294func (i *iterator) nextValidIssueEdit() bool {
295 // issueEdit.Diff == nil happen if the event is older than early 2018, Github doesn't have the data before that.
296 // Best we can do is to ignore the event.
297 if issueEdit := i.IssueEditValue(); issueEdit.Diff == nil || string(*issueEdit.Diff) == "" {
298 return i.NextIssueEdit()
299 }
300 return true
301}
302
303// NextIssueEdit return true if there is a next issue edit and increments the index by one.
304// It is used iterates over all the issue edits. Extra queries are made if it is necessary.
305func (i *iterator) NextIssueEdit() bool {
306 if i.err != nil {
307 return false
308 }
309
310 if i.ctx.Err() != nil {
311 return false
312 }
313
314 // this mean we looped over all available issue edits in the timeline.
315 // now we have to use i.issueEditQuery
316 if i.timeline.issueEdit.index == -2 {
317 issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
318 if i.issueEdit.index < len(issueEdits.Nodes)-1 {
319 i.issueEdit.index++
320 return i.nextValidIssueEdit()
321 }
322
323 if !issueEdits.PageInfo.HasPreviousPage {
324 i.timeline.issueEdit.index = -1
325 i.issueEdit.index = -1
326 return false
327 }
328
329 // if there is more edits, query them
330 i.issueEdit.variables["issueEditBefore"] = issueEdits.PageInfo.StartCursor
331 return i.queryIssueEdit()
332 }
333
334 issueEdits := i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits
335 // if there is no edit, the UserContentEdits given by github is empty. That
336 // means that the original message is given by the issue message.
337 //
338 // if there is edits, the UserContentEdits given by github contains both the
339 // original message and the following edits. The issue message give the last
340 // version so we don't care about that.
341 //
342 // the tricky part: for an issue older than the UserContentEdits API, github
343 // doesn't have the previous message version anymore and give an edition
344 // with .Diff == nil. We have to filter them.
345 if len(issueEdits.Nodes) == 0 {
346 return false
347 }
348
349 // loop over them timeline comment edits
350 if i.timeline.issueEdit.index < len(issueEdits.Nodes)-1 {
351 i.timeline.issueEdit.index++
352 return i.nextValidIssueEdit()
353 }
354
355 if !issueEdits.PageInfo.HasPreviousPage {
356 i.timeline.issueEdit.index = -1
357 return false
358 }
359
360 // if there is more edits, query them
361 i.initIssueEditQueryVariables()
362 i.issueEdit.variables["issueEditBefore"] = issueEdits.PageInfo.StartCursor
363 return i.queryIssueEdit()
364}
365
366// IssueEditValue return the actual issue edit value
367func (i *iterator) IssueEditValue() userContentEdit {
368 // if we are using issue edit query
369 if i.timeline.issueEdit.index == -2 {
370 issueEdits := i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits
371 return issueEdits.Nodes[i.issueEdit.index]
372 }
373
374 issueEdits := i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits
375 // else get it from timeline issue edit query
376 return issueEdits.Nodes[i.timeline.issueEdit.index]
377}
378
379func (i *iterator) queryCommentEdit() bool {
380 ctx, cancel := context.WithTimeout(i.ctx, defaultTimeout)
381 defer cancel()
382
383 if err := i.gc.Query(ctx, &i.commentEdit.query, i.commentEdit.variables); err != nil {
384 i.err = err
385 return false
386 }
387
388 commentEdits := i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits
389 // this is not supposed to happen
390 if len(commentEdits.Nodes) == 0 {
391 i.timeline.commentEdit.index = -1
392 return false
393 }
394
395 reverseEdits(commentEdits.Nodes)
396
397 i.commentEdit.index = 0
398 i.timeline.commentEdit.index = -2
399 return i.nextValidCommentEdit()
400}
401
402func (i *iterator) nextValidCommentEdit() bool {
403 // if comment edit diff is a nil pointer or points to an empty string look for next value
404 if commentEdit := i.CommentEditValue(); commentEdit.Diff == nil || string(*commentEdit.Diff) == "" {
405 return i.NextCommentEdit()
406 }
407 return true
408}
409
410// NextCommentEdit return true if there is a next comment edit and increments the index by one.
411// It is used iterates over all the comment edits. Extra queries are made if it is necessary.
412func (i *iterator) NextCommentEdit() bool {
413 if i.err != nil {
414 return false
415 }
416
417 if i.ctx.Err() != nil {
418 return false
419 }
420
421 // same as NextIssueEdit
422 if i.timeline.commentEdit.index == -2 {
423 commentEdits := i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits
424 if i.commentEdit.index < len(commentEdits.Nodes)-1 {
425 i.commentEdit.index++
426 return i.nextValidCommentEdit()
427 }
428
429 if !commentEdits.PageInfo.HasPreviousPage {
430 i.timeline.commentEdit.index = -1
431 i.commentEdit.index = -1
432 return false
433 }
434
435 // if there is more comment edits, query them
436 i.commentEdit.variables["commentEditBefore"] = commentEdits.PageInfo.StartCursor
437 return i.queryCommentEdit()
438 }
439
440 commentEdits := i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index].Node.IssueComment
441 // if there is no comment edits
442 if len(commentEdits.UserContentEdits.Nodes) == 0 {
443 return false
444 }
445
446 // loop over them timeline comment edits
447 if i.timeline.commentEdit.index < len(commentEdits.UserContentEdits.Nodes)-1 {
448 i.timeline.commentEdit.index++
449 return i.nextValidCommentEdit()
450 }
451
452 if !commentEdits.UserContentEdits.PageInfo.HasPreviousPage {
453 i.timeline.commentEdit.index = -1
454 return false
455 }
456
457 i.initCommentEditQueryVariables()
458 if i.timeline.index == 0 {
459 i.commentEdit.variables["timelineAfter"] = i.timeline.lastEndCursor
460 } else {
461 i.commentEdit.variables["timelineAfter"] = i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index-1].Cursor
462 }
463
464 i.commentEdit.variables["commentEditBefore"] = commentEdits.UserContentEdits.PageInfo.StartCursor
465
466 return i.queryCommentEdit()
467}
468
469// CommentEditValue return the actual comment edit value
470func (i *iterator) CommentEditValue() userContentEdit {
471 if i.timeline.commentEdit.index == -2 {
472 return i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes[i.commentEdit.index]
473 }
474
475 return i.timeline.query.Repository.Issues.Nodes[0].TimelineItems.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.Nodes[i.timeline.commentEdit.index]
476}
477
478func reverseEdits(edits []userContentEdit) {
479 for i, j := 0, len(edits)-1; i < j; i, j = i+1, j-1 {
480 edits[i], edits[j] = edits[j], edits[i]
481 }
482}