iterator.go

  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	// sticky error
 50	err error
 51
 52	// started
 53	started bool
 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
 65func NewIterator(user, project, token string, since time.Time) *iterator {
 66	return &iterator{
 67		gc:       buildClient(token),
 68		since:    since,
 69		capacity: 10,
 70		timeline: timelineIterator{
 71			index:       -1,
 72			issueEdit:   indexer{-1},
 73			commentEdit: indexer{-1},
 74			variables: map[string]interface{}{
 75				"owner": githubv4.String(user),
 76				"name":  githubv4.String(project),
 77			},
 78		},
 79		commentEdit: commentEditIterator{
 80			index: -1,
 81			variables: map[string]interface{}{
 82				"owner": githubv4.String(user),
 83				"name":  githubv4.String(project),
 84			},
 85		},
 86		issueEdit: issueEditIterator{
 87			index: -1,
 88			variables: map[string]interface{}{
 89				"owner": githubv4.String(user),
 90				"name":  githubv4.String(project),
 91			},
 92		},
 93	}
 94}
 95
 96// init issue timeline variables
 97func (i *iterator) initTimelineQueryVariables() {
 98	i.timeline.variables["issueFirst"] = githubv4.Int(1)
 99	i.timeline.variables["issueAfter"] = (*githubv4.String)(nil)
100	i.timeline.variables["issueSince"] = githubv4.DateTime{Time: i.since}
101	i.timeline.variables["timelineFirst"] = githubv4.Int(i.capacity)
102	i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
103	// Fun fact, github provide the comment edition in reverse chronological
104	// order, because haha. Look at me, I'm dying of laughter.
105	i.timeline.variables["issueEditLast"] = githubv4.Int(i.capacity)
106	i.timeline.variables["issueEditBefore"] = (*githubv4.String)(nil)
107	i.timeline.variables["commentEditLast"] = githubv4.Int(i.capacity)
108	i.timeline.variables["commentEditBefore"] = (*githubv4.String)(nil)
109}
110
111// init issue edit variables
112func (i *iterator) initIssueEditQueryVariables() {
113	i.issueEdit.variables["issueFirst"] = githubv4.Int(1)
114	i.issueEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
115	i.issueEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
116	i.issueEdit.variables["issueEditLast"] = githubv4.Int(i.capacity)
117	i.issueEdit.variables["issueEditBefore"] = (*githubv4.String)(nil)
118}
119
120// init issue comment variables
121func (i *iterator) initCommentEditQueryVariables() {
122	i.commentEdit.variables["issueFirst"] = githubv4.Int(1)
123	i.commentEdit.variables["issueAfter"] = i.timeline.variables["issueAfter"]
124	i.commentEdit.variables["issueSince"] = githubv4.DateTime{Time: i.since}
125	i.commentEdit.variables["timelineFirst"] = githubv4.Int(1)
126	i.commentEdit.variables["timelineAfter"] = (*githubv4.String)(nil)
127	i.commentEdit.variables["commentEditLast"] = githubv4.Int(i.capacity)
128	i.commentEdit.variables["commentEditBefore"] = (*githubv4.String)(nil)
129}
130
131// reverse UserContentEdits arrays in both of the issue and
132// comment timelines
133func (i *iterator) reverseTimelineEditNodes() {
134	node := i.timeline.query.Repository.Issues.Nodes[0]
135	reverseEdits(node.UserContentEdits.Nodes)
136	for index, ce := range node.Timeline.Edges {
137		if ce.Node.Typename == "IssueComment" && len(node.Timeline.Edges) != 0 {
138			reverseEdits(node.Timeline.Edges[index].Node.IssueComment.UserContentEdits.Nodes)
139		}
140	}
141}
142
143// Error return last encountered error
144func (i *iterator) Error() error {
145	return i.err
146}
147
148func (i *iterator) queryIssue() bool {
149	if err := i.gc.Query(context.TODO(), &i.timeline.query, i.timeline.variables); err != nil {
150		i.err = err
151		return false
152	}
153
154	if len(i.timeline.query.Repository.Issues.Nodes) == 0 {
155		return false
156	}
157
158	i.reverseTimelineEditNodes()
159	return true
160}
161
162// Next issue
163func (i *iterator) NextIssue() bool {
164	// we make the first move
165	if !i.started {
166		// init variables and goto queryIssue block
167		i.initTimelineQueryVariables()
168		i.started = true
169		return i.queryIssue()
170	}
171
172	if i.err != nil {
173		return false
174	}
175
176	if !i.timeline.query.Repository.Issues.PageInfo.HasNextPage {
177		return false
178	}
179
180	// if we have more issues, query them
181	i.timeline.variables["timelineAfter"] = (*githubv4.String)(nil)
182	i.timeline.variables["issueAfter"] = i.timeline.query.Repository.Issues.PageInfo.EndCursor
183	i.timeline.index = -1
184
185	// store cursor for future use
186	i.timeline.lastEndCursor = i.timeline.query.Repository.Issues.Nodes[0].Timeline.PageInfo.EndCursor
187
188	// query issue block
189	return i.queryIssue()
190}
191
192func (i *iterator) IssueValue() issueTimeline {
193	return i.timeline.query.Repository.Issues.Nodes[0]
194}
195
196func (i *iterator) NextTimeline() bool {
197	if i.err != nil {
198		return false
199	}
200
201	if len(i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges) == 0 {
202		return false
203	}
204
205	if i.timeline.index < min(i.capacity, len(i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges))-1 {
206		i.timeline.index++
207		return true
208	}
209
210	if !i.timeline.query.Repository.Issues.Nodes[0].Timeline.PageInfo.HasNextPage {
211		return false
212	}
213
214	i.timeline.lastEndCursor = i.timeline.query.Repository.Issues.Nodes[0].Timeline.PageInfo.EndCursor
215
216	// more timelines, query them
217	i.timeline.variables["timelineAfter"] = i.timeline.query.Repository.Issues.Nodes[0].Timeline.PageInfo.EndCursor
218	if err := i.gc.Query(context.TODO(), &i.timeline.query, i.timeline.variables); err != nil {
219		i.err = err
220		return false
221	}
222
223	i.reverseTimelineEditNodes()
224	i.timeline.index = 0
225	return true
226}
227
228func (i *iterator) TimelineValue() timelineItem {
229	return i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node
230}
231
232func (i *iterator) queryIssueEdit() bool {
233	if err := i.gc.Query(context.TODO(), &i.issueEdit.query, i.issueEdit.variables); err != nil {
234		i.err = err
235		//i.timeline.issueEdit.index = -1
236		return false
237	}
238
239	// reverse issue edits because github
240	reverseEdits(i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes)
241
242	// this is not supposed to happen
243	if len(i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes) == 0 {
244		i.timeline.issueEdit.index = -1
245		return false
246	}
247
248	i.issueEdit.index = 0
249	i.timeline.issueEdit.index = -2
250	return i.nextValidIssueEdit()
251}
252
253func (i *iterator) nextValidIssueEdit() bool {
254	// issueEdit.Diff == nil happen if the event is older than early 2018, Github doesn't have the data before that.
255	// Best we can do is to ignore the event.
256	if issueEdit := i.IssueEditValue(); issueEdit.Diff == nil || string(*issueEdit.Diff) == "" {
257		return i.NextIssueEdit()
258	}
259	return true
260}
261
262func (i *iterator) NextIssueEdit() bool {
263	if i.err != nil {
264		return false
265	}
266
267	// this mean we looped over all available issue edits in the timeline.
268	// now we have to use i.issueEditQuery
269	if i.timeline.issueEdit.index == -2 {
270		if i.issueEdit.index < min(i.capacity, len(i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes))-1 {
271			i.issueEdit.index++
272			return i.nextValidIssueEdit()
273		}
274
275		if !i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.PageInfo.HasPreviousPage {
276			i.timeline.issueEdit.index = -1
277			i.issueEdit.index = -1
278			return false
279		}
280
281		// if there is more edits, query them
282		i.issueEdit.variables["issueEditBefore"] = i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.PageInfo.StartCursor
283		return i.queryIssueEdit()
284	}
285
286	// if there is no edit, the UserContentEdits given by github is empty. That
287	// means that the original message is given by the issue message.
288	//
289	// if there is edits, the UserContentEdits given by github contains both the
290	// original message and the following edits. The issue message give the last
291	// version so we don't care about that.
292	//
293	// the tricky part: for an issue older than the UserContentEdits API, github
294	// doesn't have the previous message version anymore and give an edition
295	// with .Diff == nil. We have to filter them.
296	if len(i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes) == 0 {
297		return false
298	}
299
300	// loop over them timeline comment edits
301	if i.timeline.issueEdit.index < min(i.capacity, len(i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes))-1 {
302		i.timeline.issueEdit.index++
303		return i.nextValidIssueEdit()
304	}
305
306	if !i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits.PageInfo.HasPreviousPage {
307		i.timeline.issueEdit.index = -1
308		return false
309	}
310
311	// if there is more edits, query them
312	i.initIssueEditQueryVariables()
313	i.issueEdit.variables["issueEditBefore"] = i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits.PageInfo.StartCursor
314	return i.queryIssueEdit()
315}
316
317func (i *iterator) IssueEditValue() userContentEdit {
318	// if we are using issue edit query
319	if i.timeline.issueEdit.index == -2 {
320		return i.issueEdit.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes[i.issueEdit.index]
321	}
322
323	// else get it from timeline issue edit query
324	return i.timeline.query.Repository.Issues.Nodes[0].UserContentEdits.Nodes[i.timeline.issueEdit.index]
325}
326
327func (i *iterator) queryCommentEdit() bool {
328	if err := i.gc.Query(context.TODO(), &i.commentEdit.query, i.commentEdit.variables); err != nil {
329		i.err = err
330		return false
331	}
332
333	// this is not supposed to happen
334	if len(i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes) == 0 {
335		i.timeline.commentEdit.index = -1
336		return false
337	}
338
339	reverseEdits(i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes)
340
341	i.commentEdit.index = 0
342	i.timeline.commentEdit.index = -2
343	return i.nextValidCommentEdit()
344}
345
346func (i *iterator) nextValidCommentEdit() bool {
347	// if comment edit diff is a nil pointer or points to an empty string look for next value
348	if commentEdit := i.CommentEditValue(); commentEdit.Diff == nil || string(*commentEdit.Diff) == "" {
349		return i.NextCommentEdit()
350	}
351	return true
352}
353
354func (i *iterator) NextCommentEdit() bool {
355	if i.err != nil {
356		return false
357	}
358
359	// same as NextIssueEdit
360	if i.timeline.commentEdit.index == -2 {
361
362		if i.commentEdit.index < min(i.capacity, len(i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes))-1 {
363			i.commentEdit.index++
364			return i.nextValidCommentEdit()
365		}
366
367		if !i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.PageInfo.HasPreviousPage {
368			i.timeline.commentEdit.index = -1
369			i.commentEdit.index = -1
370			return false
371		}
372
373		// if there is more comment edits, query them
374		i.commentEdit.variables["commentEditBefore"] = i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.PageInfo.StartCursor
375		return i.queryCommentEdit()
376	}
377
378	// if there is no comment edits
379	if len(i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.Nodes) == 0 {
380		return false
381	}
382
383	// loop over them timeline comment edits
384	if i.timeline.commentEdit.index < min(i.capacity, len(i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.Nodes))-1 {
385		i.timeline.commentEdit.index++
386		return i.nextValidCommentEdit()
387	}
388
389	if !i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.PageInfo.HasPreviousPage {
390		i.timeline.commentEdit.index = -1
391		return false
392	}
393
394	i.initCommentEditQueryVariables()
395	if i.timeline.index == 0 {
396		i.commentEdit.variables["timelineAfter"] = i.timeline.lastEndCursor
397	} else {
398		i.commentEdit.variables["timelineAfter"] = i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index-1].Cursor
399	}
400
401	i.commentEdit.variables["commentEditBefore"] = i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.PageInfo.StartCursor
402
403	return i.queryCommentEdit()
404}
405
406func (i *iterator) CommentEditValue() userContentEdit {
407	if i.timeline.commentEdit.index == -2 {
408		return i.commentEdit.query.Repository.Issues.Nodes[0].Timeline.Nodes[0].IssueComment.UserContentEdits.Nodes[i.commentEdit.index]
409	}
410
411	return i.timeline.query.Repository.Issues.Nodes[0].Timeline.Edges[i.timeline.index].Node.IssueComment.UserContentEdits.Nodes[i.timeline.commentEdit.index]
412}
413
414func min(a, b int) int {
415	if a > b {
416		return b
417	}
418
419	return a
420}
421
422func reverseEdits(edits []userContentEdit) {
423	for i, j := 0, len(edits)-1; i < j; i, j = i+1, j-1 {
424		edits[i], edits[j] = edits[j], edits[i]
425	}
426}