fix(im): cap basic_batch user_ids at 10 per API limit

[haozhenghua-code]

Summary

The POST /contact/v3/users/basic_batch endpoint accepts 1~10 user_ids per request (doc). batchResolveByBasicContact in shortcuts/im/convert_lib/helpers.go was chunking by 50, so whenever the user-identity sender-name resolver had >10 unresolved IDs, the single oversized request was rejected and the whole batch was silently skipped — leaving sender names empty in the output of im +chat-messages-list, +messages-search, +messages-mget, +threads-messages-list, etc.

Changes

• shortcuts/im/convert_lib/helpers.go: lower batchSize from 50 to 10 in batchResolveByBasicContact and add a comment citing the API limit. The sibling batchResolveUsers (calls the different GET /contact/v3/users/batch endpoint, cap 50) is untouched.
• shortcuts/im/convert_lib/helpers_test.go: add TestBatchResolveByBasicContactRespectsAPILimit that feeds 25 missing IDs and asserts the mock server sees three requests of size 10 / 10 / 5 and that every resolved name ends up in the name map.

Test Plan

Automated

• go test ./shortcuts/im/convert_lib/... passes (new + existing tests)
• go vet ./... and go build ./... clean

End-to-end (built binary, live Feishu API)

Exercised the real im +chat-messages-list flow on two internal group chats (chat IDs and user identifiers redacted). Compared the number of unique user senders vs. how many ended up with their display name populated after ResolveSenderNames → AttachSenderNames.

Case	Identity	batchSize	Unique user senders	Names resolved	Names missing
Positive — user identity, after fix	user	10	31	31	0
Positive — bot identity, after fix (unchanged batchResolveUsers path, different API)	bot	n/a	4	4	0
Negative — user identity, reverted batchSize to 50 (reproduces the bug)	user	50	31	0	31

The negative run demonstrates the bug was real: with 31 unresolved IDs packed into a single oversized request, the server rejects it and the resolver's break leaves the whole name map empty. After the fix, the same 31 IDs are split across 4 batches (10/10/10/1) and every name comes back.

Related Issues

• None

[coderabbitai]

📝 Walkthrough

Walkthrough

Reduced the batch size constant from 50 to 10 in batchResolveByBasicContact for the /open-apis/contact/v3/users/basic_batch endpoint, resulting in smaller per-request batches. Added a corresponding unit test to verify the batching pattern with 25 IDs produces expected batch splits.

Changes

Cohort / File(s)	Summary
Batch Size Adjustment shortcuts/im/convert_lib/helpers.go	Changed batchSize constant from 50 to 10 in batchResolveByBasicContact to align with per-request API limits.
Batching Verification Test shortcuts/im/convert_lib/helpers_test.go	Added TestBatchResolveByBasicContactRespectsAPILimit to validate the new batch size of 10 IDs per request and verify batching pattern [10, 10, 5] for 25 IDs. Extended imports with encoding/json and io.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Suggested labels

domain/im, size/M

Suggested reviewers

• sammi-bytedance
• YangJunzhou-01
• zgz2048

Poem

🐰 Ten by ten, we hop along,
Batching smaller, staying strong,
No more fifty in a heap,
Ten per request, a measured leap! 🥕

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 25.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: capping the basic_batch user_ids limit at 10 to match the API's per-request constraint.
Description check	✅ Passed	The pull request description comprehensively addresses all required template sections with detailed context, code changes, test plan with automated and manual verification results, and clear problem motivation.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main@c1d6042). Learn more about missing BASE report.

Additional details and impacted files

@@           Coverage Diff           @@
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  Coverage        ?   59.96%           
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  Files           ?      388           
  Lines           ?    33147           
  Branches        ?        0           
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  Hits            ?    19878           
  Misses          ?    11400           
  Partials        ?     1869           

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[github-actions]

🚀 PR Preview Install Guide

🧰 CLI update

npm i -g https://pkg.pr.new/larksuite/cli/@larksuite/cli@5d200a6c6e3a1b800a3694729654471e61f34bba

🧩 Skill update

npx skills add haozhenghua-code/larksuite-cli#fix/basic-batch-size -y -g