What data is the commit parameter in increment()? - vuejs2

The parameter commit is mentioned in the Vuex documentation
What data is the commit parameter in increment()?
https://sm.ms/image/A5qnBI3jSKU4pP1

Actions api's Docs here
It describe what context is in action
{
state, // same as `store.state`, or local state if in modules
rootState, // same as `store.state`, only in modules
commit, // same as `store.commit`
dispatch, // same as `store.dispatch`
getters, // same as `store.getters`, or local getters if in modules
rootGetters // same as `store.getters`, only in modules
}
And with ES6 Destructuring
It is equivalent to the following code
increment(context){
const {commit} = context;
// ...
}
So the commit is same as store.commit
commit(type: string, payload?: any, options?: Object)
commit(mutation: Object, options?: Object)
Commit a mutation. options can have root: true that allows to commit root mutations in namespaced modules. Details

Related

Vuex: How to replace function emitting between parent and child with Vuex?

I am using Vuex for state right now and taking advantage of getters to acquire state so that I don't have to use props. However, I am curious if I can use Vuex to replace this type of function emitting. How would that be done with Vuex, if it's even possible.
Parent
<child-component #handleselectproduct="selectProduct"></child-component>
selectProduct: function() {
axios.get()
}
Child
<button #click="selectProduct></button>
selectProduct: function() {
this.$emit('handleselectproductselection');
}
You could use vuex actions and mutations. Mutations are used for synchronous and actions for asynchronous calls. You could imagine them as setters as opposed to getters that you already use. So in your current example, you would call an action which may or may not set a state property through a mutation. you would define this action with:
const store = new Vuex.Store({
state: {
selectedProduct: {}
},
getters: {
getSelectedProduct: state => {
return state.selectedProduct
}
},
mutations: {
selectProduct(state, payload) {
state.selectedProduct = payload
}
},
actions: {
async selectProduct(context, axios) {
const { commit } = context
const product = await axios.get(...) // some call
commit('selectProduct', product)
}
}
})
After defining these, you can call the action through the this.$store.dispatch('selectProduct', axios) method in the child component and have your result available in the parent component or wherever else you may need it. And if you need some sort of notification that the property has changed (you need to do some change to the selectedProduct data and then show it), you can set a watcher function on the respective getter or just use computed properties that use the getter and they will pick up the change.
You can find out more about actions at https://vuex.vuejs.org/guide/actions.html

Vue test utils with nuxt - committing a mutation

I am using vue test utils with nuxt, I have a standard mutation
this.$store.commit(
'users/UPDATE_NAME',
this.username
)
In my .spec I am trying to access this mutation but I get the error
TypeError: Cannot read property 'commit' of undefined
I have tried mocking it too
it("It should commit the change name mutation", () => {
const wrapper = shallowMount(ChangeName, {
mocks: {
$store: {
// what goes here
}
but don't know how to setup the wrapper so it has access to the mutation inside the module 'users'
this.$store.commit('users/UPDATE_NAME',this.username)
How do I setup the .spec to have access to this mutation?

Access a namespaced getter function in a middleware in nuxtjs

I have a store module called store/auth.js in that I have a getter
export const getters = {
isAuthenticated(state) {
return state.token != null
}
}
Now I want to call this namespaced getter in my middleware. How would I go about calling that getter?
This seems to work but even without namespacing anything ...
export default function (context) {
if(!context.store.getters.isAuthenticated)
context.redirect('/')
}
}
Do the getters behave differently than an action or mutation where I have to call auth/?
context.store.dispatch("auth/SomeVuexAction")
You can access vuex getters as below:
context.store.getters["modulename/gettername"]
i.e.(In your case) mention correct module and getter name
context.store.getters["auth/isAuthenticated"]

Better approach handling: 'Do not mutate vuex store state outside mutation handlers' errors

Beforehand: My application is working as intended, but I want to know if there's an better approach to the problem, I was having.
Situation: I have a project where I am currently implemeneting a Permission-System. The current flow is, to load specific objects (lets take user in this case) and inject the permissions afterwards.
Problem: Getting 'Do not mutate vuex store state outside mutation handlers.' error inside vuex-action.
Question: Is there a better way to omit the error than my approach below?
Simplified it looks like this (here I am getting my objects from our API and storing them in vuex-store):
// user.js (vuex-module)
state: {
user: null,
},
mutations: {
// ...
setUser(state, user) {
state.user = user
}
}
actions: {
// ... other vuex-actions
async login({commit, dispatch}, payload) {
let userFromDb = DbUtil.getUser(payload) // is an axios call to our api
// here the permissions get injected
// action in another vuex-module
dispatch('permissions/injectPermissions', userFromDb)
// commiting to store
commit('setUser', userFromDb)
return userFromDb
}
}
My permissions.js (here I am injecting the permissions to my object):
// permissions.js (vuex-module)
actions: {
// ... other vuex-actions
// payload = user in this example
async injectPermissions({commit, dispatch}, payload) {
let permissionFromDb = DbUtil.getPermissions(/* ... */)
payload.permissions = permissionFromDb // -> Here I am getting 'Do not mutate vuex store state outside mutation handlers.'-Error, because `payload` == the user from user-state
return payload
}
}
Workaround: I added a mutation which changes the user-state object for me inside a mutation-handler.
mutations: {
/**
* A 'set'-wrapper to mutate vuex-store variable inside a mutation to avoid getting a error.
* #param state
* #param payload:
* object - object to be mutated
* prop - prop inside object that is affected
* value - value that should be assigned
*/
setWrapper(state, payload) {
let { object, prop, value } = payload
object[prop] = value
}
}
The line where the error was thrown before gets changed to:
commit('setWrapper', {
object: payload,
prop: 'permissions',
value: permissionFromDb
})
Actions do not mutate the state.
Actions are there to perform asynchronous tasks.
When you want to change the state within an action, you have to rely on a mutation by using this syntax: commit('MUTATION_NAME', payload)
Then:
MUATATION_NAME(state, payload) {
state.permissions = payload.permissions
}
This is the cleanest and most correct way.

Vuex | How to commit a global mutation in a module action?

I have an action in a namespaced module and a global mutation (i.e. not in a module). I would like to be able to commit the global mutation inside the action.
// Global mutation
export default {
globalMutation (state, payload) {
...
}
}
// Action in a namespaced module
export default {
namespaced: true,
actions: {
namespacedAction ({ commit, dispatch, state }, payload) {
commit({ type: 'globalMutation' })
}
}
}
When the namespaced action is dispatched, Vuex displays:
[vuex] unknown local mutation type: globalMutation, global type: module/globalMutation
Is there an option I can pass to the commit function to call this global mutation?
Looks like I just found a way with the { root: true } parameter.
commit('globalMutation', payload, { root: true })
If module is namespaced, use global path instead:
commit('module/mutation', payload, { root: true })