Feature/history api#8

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yisiliu wants to merge 8 commits intomasterfrom

feature/history_api

Commits on Sep 10, 2020

WIP: Improve the code
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committed

Commits on Sep 11, 2020

Commits on Sep 15, 2020

fix compile error
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Commits on Sep 17, 2020

Commits on Sep 18, 2020