AppCenter Yarn 1.19 error Incorrect integrity when fetching from the cache - react-native

Question

I have a React Native app hosted on Microsoft App center. The builds (both iOS and android) are failing because of yarn 1.19 (error Incorrect integrity when fetching from the cache)
I tried to remove the package-lock.json but it didn't help.
I would like to downgrade yarn or execute the cache clean command but don't know where to execute it.
I have installed the appcenter cli version 2.2.1 and successfully connected to it.
Where could I execute yarn cache clean for example?
I've read I could also create a script but I have no idea where to place it and how it should look like. Should it be both in the ios and android directory? Or in the root? Thank you

Answer 1

I actually noticed that I had a yarn.lock back from the initial commit, even though we are using npm in the team.
In the build logs, there is this line:
/bin/sh -c if [ -f yarn.lock ]; then { yarn install && yarn list --depth=0; } else npm install; fi
So I deleted the yarn.lock file and now it builds successfully using npm!

Answer 2

Not sure whether you build your React app with Azure Devops pipeline. If yes, you can use Command line task to achieve the things you want to do.
If the agent you used is hosted agent during the build, since each build will use a completely new VM, you need to install the AppCenter cli once per build.
Use follow command to install the AppCenter cli:
sudo npm install -g appcenter-cli
Then logging in it:
appcenter login --token {Token}
Here, you need first generate the token with this doc described: Go and login to https://appcenter.ms/ -> Click Self Avatar -> Choose Account Settings -> Click on API Tokens -> Click New API token then select the corresponding the scope for this token.
Copy and use it in this pipeline task. Note: Recommend you store
this token with secret variable for security.
Now, you can execute the clean command: yarn cache clean.
Where to place it and how it should look like?
According to your description, you need place this command line task into the first step, then it could clean the Yarn cache firstly.
Also, because of the image configuration that the hosted agent is using, its installed node.js version is 6.7.0, this does not match the runtime environment for AppCenter cli. You need also run Node.js tool installer task to install node.js v10.0.0.
All of them should look like this:
Should it be both in the ios and android directory?
As I mentioned previously, for Hosted agent, each build will use a completely new VM. So yes, you must execute these two steps firstly in every build.
If what you used is your private agent, since you have installed the AppCenter cli locally, the agent will automatically call the local configuration when running the command line task. At this time, you just need to skip the install command in the command task:

Answer 3

We fixed it by adding a "yarn cache clean" in appcenter-post-clone.sh, you can add this shell script in root of project.
See this docs for details.