refactor: simplify init logics

src/driver/core/SideBar.ts

@@ -2,6 +2,7 @@ import { ConfigsContextShape } from 'containers/ConfigsContext'
 import { GetCreatedMethod, MethodCreator } from 'driver/connect'
 import { errors, platform, platformName } from 'platforms'
 import * as DOMHelper from 'utils/DOMHelper'
+import { createPromiseQueue } from 'utils/general'
 
 export type Props = {
   configContext: ConfigsContextShape
@@ -26,7 +27,6 @@ export type ConnectorState = {
   initializingPromise: Promise<void> | null
 } & {
   init: GetCreatedMethod<typeof init>
-  setMetaData: GetCreatedMethod<typeof setMetaData>
   setShouldShow: GetCreatedMethod<typeof setShouldShow>
   toggleShowSideBar: GetCreatedMethod<typeof toggleShowSideBar>
   toggleShowSettings: GetCreatedMethod<typeof toggleShowSettings>
@@ -34,18 +34,10 @@ export type ConnectorState = {
 
 type BoundMethodCreator<Args extends any[] = []> = MethodCreator<Props, ConnectorState, Args>
 
-export const init: BoundMethodCreator = dispatch => async () => {
-  const {
-    state: { initializingPromise },
-  } = dispatch.get()
-  if (initializingPromise) await initializingPromise
+const promiseQueue = createPromiseQueue()
 
-  let done: any = null // cannot use type `(() => void) | null` here
-  dispatch.set({
-    initializingPromise: new Promise(resolve => {
-      done = () => resolve()
-    }),
-  })
+export const init: BoundMethodCreator = dispatch => async () => {
+  const leave = await promiseQueue.enter()
 
   try {
     const metaData = platform.resolveMeta()
@@ -53,90 +45,85 @@ export const init: BoundMethodCreator = dispatch => async () => {
       dispatch.set({ disabled: true })
       return
     }
+    const { userName, repoName, branchName } = metaData
+
     DOMHelper.markGitakoReadyState(true)
     dispatch.set({
       errorDueToAuth: false,
       showSettings: false,
       logoContainerElement: DOMHelper.insertLogoMountPoint(),
     })
-    dispatch.call(setMetaData, metaData)
 
     const {
       props: { configContext },
     } = dispatch.get()
     const { accessToken } = configContext.val
 
-    if (!metaData.userName || !metaData.repoName) return
-    const guessDefaultBranch = 'master'
-    const getTreeDataAggressively = platform.getTreeData(
+    const guessDefaultBranch = 'master' // when to switch to 'main'?
+    let getTreeData = platform.getTreeData(
       {
-        branchName: metaData.branchName || guessDefaultBranch,
-        userName: metaData.userName,
-        repoName: metaData.repoName,
+        branchName: branchName || guessDefaultBranch,
+        userName,
+        repoName,
       },
       '/',
       true,
       accessToken,
     )
-    const caughtAggressiveError = getTreeDataAggressively?.catch(error => {
-      // 1. the repo has no master branch
-      // 2. detect branch name from DOM failed
-      // 3. not very possible...
-      // not handle this error immediately
-      return error
-    })
-    let getTreeData = getTreeDataAggressively
-    const metaDataFromAPI = await platform.getMetaData(
-      {
-        userName: metaData.userName,
-        repoName: metaData.repoName,
-      },
-      accessToken,
-    )
-    const projectDefaultBranchName = metaDataFromAPI?.defaultBranchName
-    const detectedBranchName = metaData.branchName
-    if (
-      !detectedBranchName &&
-      projectDefaultBranchName &&
-      projectDefaultBranchName !== metaData.branchName &&
-      metaData.type !== 'pull'
-    ) {
-      // Accessing repository's non-homepage(no branch name in URL, nor in DOM)
-      // We predicted its default branch to be 'master' and sent aggressive request
-      // Throw that request due to the repo do not use {defaultBranchName} as default branch
-      metaData.branchName = projectDefaultBranchName
-      getTreeData = platform.getTreeData(
-        {
-          branchName: metaData.branchName,
-          userName: metaData.userName,
-          repoName: metaData.repoName,
-        },
-        '/',
-        true,
-        accessToken,
-      )
+    getTreeData.catch(error => error) // catch it early to prevent the error being raised higher
+
+    const metaDataFromAPI = await platform.getMetaData({ userName, repoName }, accessToken)
+
+    if (branchName) {
+      const safeMetaData = {
+        ...metaDataFromAPI,
+        userName,
+        repoName,
+        branchName,
+      }
+      dispatch.set({ metaData: safeMetaData })
+      getTreeData.catch(error => {
+        dispatch.call(handleError, error)
+      })
     } else {
-      caughtAggressiveError.then(error => {
-        // aggressive requested correct branch but ends in failure (e.g. project is empty)
-        if (error instanceof Error) {
-          dispatch.call(handleError, error)
-        }
-      })
+      const { defaultBranchName } = metaDataFromAPI
+
+      if (!defaultBranchName) {
+        throw new Error(`Failed resolving default branch name`)
+      }
+
+      const safeMetaData = {
+        ...metaDataFromAPI,
+        userName,
+        repoName,
+        branchName: defaultBranchName,
+      }
+      dispatch.set({ metaData: safeMetaData })
+
+      if (defaultBranchName !== guessDefaultBranch && metaData.type !== 'pull') {
+        // Accessing repository's non-homepage(no branch name in URL, nor in DOM)
+        // We predicted its default branch to be 'master' and sent aggressive request
+        // Throw that request due to the repo do not use {defaultBranchName} as default branch
+        getTreeData = platform.getTreeData(
+          {
+            branchName: defaultBranchName,
+            userName,
+            repoName,
+          },
+          '/',
+          true,
+          accessToken,
+        )
+      }
     }
-    getTreeData
-      .then(async ({ root: treeData, defer }) => {
-        if (treeData) {
-          dispatch.set({ treeData, defer })
-        }
-      })
-      .catch(err => dispatch.call(handleError, err))
-    Object.assign(metaData, metaDataFromAPI)
-    dispatch.call(setMetaData, metaData)
+
+    const { root: treeData, defer } = await getTreeData
+    dispatch.set({ treeData, defer })
   } catch (err) {
     dispatch.call(handleError, err)
-  } finally {
-    if (done) done()
   }
+
+  leave()
 }
 
 export const handleError: BoundMethodCreator<[Error]> = dispatch => async err => {
@@ -197,6 +184,3 @@ export const toggleShowSettings: BoundMethodCreator = dispatch => () =>
   dispatch.set(({ showSettings }) => ({
     showSettings: !showSettings,
   }))
-
-export const setMetaData: BoundMethodCreator<[ConnectorState['metaData']]> = dispatch => metaData =>
-  dispatch.set({ metaData })

src/platforms/GitHub/URLHelper.ts

@@ -1,6 +1,8 @@
 import { raiseError } from 'analytics'
 
-export function parse(): Pick<MetaData, 'userName' | 'repoName' | 'type'> & { path: string[] } {
+export function parse(): Partial<Pick<MetaData, 'userName' | 'repoName' | 'type'>> & {
+  path: string[]
+} {
   const { pathname } = window.location
   let [
     ,

src/platforms/GitHub/index.ts

@@ -101,10 +101,17 @@ export const GitHub: Platform = {
       branchName = DOMHelper.getCurrentBranch() || URLHelper.parseSHA()
     }
 
+    const { userName, repoName, type } = URLHelper.parse()
+    if (!userName || !repoName) {
+      return null
+    }
+
     const metaData = {
-      ...URLHelper.parse(),
+      userName,
+      repoName,
+      type,
       branchName,
-    } as MetaData
+    }
     return metaData
   },
   async getMetaData({ userName, repoName }, accessToken) {
@@ -202,14 +209,14 @@ export const GitHub: Platform = {
       })),
     )
 
-    const gitModules = root.contents?.find(item => item.name === '.gitmodules')
-    if (gitModules) {
-      if (userName && repoName && gitModules.sha) {
-        const blobData = await API.getBlobData(userName, repoName, gitModules.sha, accessToken)
+    const gitModules = root.contents?.find(
+      item => item.type === 'blob' && item.name === '.gitmodules',
+    )
+    if (gitModules?.sha) {
+      const blobData = await API.getBlobData(userName, repoName, gitModules.sha, accessToken)
 
-        if (blobData && blobData.encoding === 'base64' && blobData.content) {
-          await resolveGitModules(root, Base64.decode(blobData.content))
-        }
+      if (blobData && blobData.encoding === 'base64' && blobData.content) {
+        await resolveGitModules(root, Base64.decode(blobData.content))
       }
     }
 

src/platforms/Gitea/index.ts

@@ -82,15 +82,23 @@ export const Gitea: Platform = {
       return null
     }
 
-    let detectedBranchName
+    let branchName
     if (DOMHelper.isInCodePage()) {
-      detectedBranchName = DOMHelper.getCurrentBranch() || URLHelper.parseSHA()
+      branchName = DOMHelper.getCurrentBranch() || URLHelper.parseSHA()
+    }
+
+    const { userName, repoName, type } = URLHelper.parse()
+    if (!userName || !repoName) {
+      return null
     }
 
     const metaData = {
-      ...URLHelper.parse(),
-      branchName: detectedBranchName,
-    } as MetaData
+      userName,
+      repoName,
+      type,
+      branchName,
+    }
+
     return metaData
   },
   async getMetaData(partialMetaData, accessToken) {

src/platforms/Gitee/index.ts

@@ -78,17 +78,24 @@ export const Gitee: Platform = {
       return null
     }
 
-    let detectedBranchName
+    let branchName
     if (DOMHelper.isInCodePage()) {
       // not working well with non-branch blob
       // cannot handle '/' split branch name, should not use when possibly on branch page
-      detectedBranchName = DOMHelper.getCurrentBranch() || URLHelper.parseSHA()
+      branchName = DOMHelper.getCurrentBranch() || URLHelper.parseSHA()
+    }
+
+    const { userName, repoName, type } = URLHelper.parse()
+    if (!userName || !repoName) {
+      return null
     }
 
     const metaData = {
-      ...URLHelper.parse(),
-      branchName: detectedBranchName,
-    } as MetaData
+      userName,
+      repoName,
+      type,
+      branchName,
+    }
     return metaData
   },
   async getMetaData(partialMetaData, accessToken) {

src/utils/general.ts

@@ -187,3 +187,19 @@ export function withEffect<Method extends (...args: any[]) => any>(
 export function run<T>(fn: () => T) {
   return fn()
 }
+
+export function createPromiseQueue() {
+  let promise: Promise<void>
+  return {
+    async enter() {
+      let leave: () => void
+      const current = new Promise<void>(resolve => (leave = () => resolve()))
+
+      const lastPromise = promise
+      promise = current!
+      if (lastPromise) await lastPromise
+
+      return leave!
+    },
+  }
+}