Redmine

I've just been using the API to batch-update a large number of time entries (moving toggl ID from a comment into a custom field), and I noticed that a handful of records were not retrieved via `time_entries.json` (and thus weren't update), while a handful of others were returned multiple times.

- This happens for all page sizes `<= 99` that I've tried (`5`, `15`, `25`, `50`, `75`, `99`).
- Strangely for a page size `100` I get the expected output, though this could be fluke with where the page boundaries fall.
- Requests for page sizes `>= 100` return pages of `100` records.

I think It's also worth mentioning that by varying the page sizes, I see that records are not always returned in the same order...

For example, with pages of 5 records, `498` is returned twice:

- Page `n-1`: `505` `502` `503` `504` `498`
- Page `n`: `500` `498` `501` `497` `496`

Then, with pages of 25 records, `498` is returned once, with neighbours in a different order:

- Page `n`: `503` `502` `504` `500` `501` `498` `499` `497` `496` `493` `494`

I suspect that the indeterminate ordering is very related to this bug.

---

Note, I have also tried using the undocumented `page` parameter with no difference, as mentioned here: https://www.redmine.org/issues/20479

---

Some example code:

```python
import json
import itertools
import requests

base_url = 'https://redmine.example.com'
headers = {
'X-Redmine-API-Key': 'YOUR_API_KEY'
}

params = {
'limit': 5
}

count = 0
entries = {}

for i in itertools.count(0, params['limit']):
params['offset'] = i

response = requests.get(f'{base_url}/time_entries.json', params=params, headers=headers)
  content = json.loads(response.content)

num = len(content['time_entries'])
  count += num

for e in content['time_entries']:
    e_id = e['id']
    if e_id in entries:
        raise Exception(f'ID {e_id} already exists!')

entries[e_id] = e

if content['offset'] + num >= content['total_count']:
    break

print(count)
```

---

I'm running Redmine using the [`redmine:4.0.4` docker image](https://hub.docker.com/_/redmine/)

Info tab:

```
Environment:
Redmine version 4.0.4.stable
Ruby version 2.6.3-p62 (2019-04-16) [x86_64-linux]
Rails version 5.2.3
Environment production
Database adapter Mysql2
Mailer queue ActiveJob::QueueAdapters::AsyncAdapter
Mailer delivery smtp
SCM:
Subversion 1.10.4
Mercurial 4.8.2
Bazaar 2.8.0
Git 2.20.1
Filesystem
Redmine plugins:
redmine_auth_gitlab 0.0.1
```

The database is MySQL using the [`mysql/mysql-server:8.0.17` docker image](https://hub.docker.com/_/mysql).