thanks in advance!
In summary, I am using React's WYSIWYG rich text editor, and saving the text written in the editor to a MongoDB, data is sent to a server which does the insertion. My issue is that I am unable, after following recommended code, to retrieve the stored data back successfully to display it on my page. This is for a prospective blog post site.
Below I've provided all relevant code:
My Component which sends the data to the server to insert it into MongoDB, (not in order, only relevant code):
<Editor
editorState={editorState}
onEditorStateChange={handleEditorChange}
wrapperClassName="wrapper-class"
editorClassName="editor-class"
toolbarClassName="toolbar-class"
/>
const Practice = () => {
const [editorState, setEditorState] = useState(
() => EditorState.createEmpty(),
);
const [convertedContent, setConvertedContent] = useState(null);
const handleEditorChange = (state) => {
setEditorState(state);
convertContentToRaw();
}
const convertContentToRaw = () => {
const contentState = editorState.getCurrentContent();
setEditorState(editorState: {convertToRaw(contentState)});
}
const stateToSend = JSON.stringify(editorState);
try {
const response = await axios.post('http://localhost:8080/api/insert', {
content: stateToSend
})
} catch(error) {
}
In MongoDB, I've initialized 1 column for storing the WYSIWYG data, I've initialized as an empty JS object:
const wysiwygtest = new mongoose.Schema({
content: {
type: {}
}
});
As a result, my data is inserted into MongoDB as such, with everything desired clearly in data type such as RGBA etc. correct me if I'm wrong but I believe Mongo uses BSON, a form of binary based JSON, so this looks doable for retrieval:
Lastly, the code which is not working correctly, the retrieval. For this, I have no interest just yet in placing the data back into the text editor. Rather, I'd like to display it on the page like a typical blog post. However, I'm unable to even log to the console as of yet.
I am parsing the data back to JSON using JSON.parse, converting JSON to JS object using createFromRaw and using EdiorState (even though I don't have the text editor in this component but this seems to be needed to convert the data fully..) to convert fully:
useEffect( async () => {
try {
const response = await axios.get('http://localhost:8080/api/query', {
_id: '60da9673b996f54d507dbfc5'
});
const content = response;
if(content) {
const convertedContent =
EditorState.createWithContent(convertFromRaw(JSON.parse(content)));
console.log('convertedContent - ', convertedContent);
}
console.log('response - ', content);
} catch(error) {
console.log('error!', error);
}
}, [])
My result for the past day and last night has been the following:
"SyntaxError: Unexpected token o in JSON at position 1" and so I'm unsure what I'm doing wrong in the data retrieval, and possibly even the insertion.
Any ideas? Thanks again!
Edit: For more reference, here is what the data looks like when output to the console without a JSON.stringify, this is the full tree of data. I can see all of the relevant data is there, but how do I convert this data and display it into a div or paragraph tag, for example?
More or less figured this out, see my solution below given the aforementioned implementation:
Firstly, I think my biggest mistake was using JSON.parse(); I did away with this with success. My guess as to why this does not work (even though I inserted into MongoDB as JSON) is because we ultimately need the draft-js.Editor Object to convert the data from the DB into an object type it can understand, in order to subsequently convert into HTML successfully, with all properties.
Below is the code with captions/descriptions:
Retrieve data (in useEffect before React component is rendered:
useEffect( async () => {
console.log('useeffect');
try {
const response = await axios.get('http://localhost:8080/api/query', {
_id: '60da9673b996f54d507dbfc5' //hard-coded id from DB for testing
});
const content = response.data; //get JSON data from MongoDB
if(content) {
const rawContent = convertFromRaw(content); //convert from JSON to contentstate understood by DraftJS, for EditorState obj to use
setEditorState(EditorState.createWithContent(rawContent)); //create EditorState based on JSON data from DB and set into component state
let currentContentAsHTML = draftToHtml(convertToRaw(editorState.getCurrentContent())); //create object which converts contentstate understood by DraftJS into a regular vanilla JS object, then take THAT and convert into HTML with "draftToHtml" function. Save that into our 2nd state titled "convertedContent" to be displayed on page for blog post
setConvertedContent(currentContentAsHTML);
}
} catch(error) {
console.log('error retrieving!', error);
} },[convertedContent]) //ensure dependency with with convertedContent state, DB/server calls take time...
In component render, return HTML which sets the innerHTML in the DOM using/passing the convertedContent state which we converted to proper HTML format in step 1.
return (
<div className="blog-container" dangerouslySetInnerHTML={createMarkup(convertedContent)}></div>
</div>
);
In step 2, we called a function entitled, "createMarkup"; here is that method. It essentially returns HTML object using the HTML converted data originally from our database. This is a bit vulnerable it terms of malicious users being able to intercept that HTML in the DOM, however, so we use a method, "purify" from "DOMPurify" class from 'isomorphic-dompurify" library. I'm using this instead of regular DOMPurify because I am using Next JS and NEXT runs on the server side as well, and DOMPurify only expects client side:
const createMarkup = (html) => {
return {
__html: DOMPurify.sanitize(html)
}
}
Related
I'm new to React as we are trying to migrate our app from AngularJS. One thing I'm struggling to wrap my head around is what's the best way to make and cache state mapping requests.
Basically, I would do a search, that returns a list of objects and one of the field is a status code (e.g. 100, 200, 300, etc.), some number. To display the result, I need to map that number to a string and we do that with a http request to the server, something like this:
GET /lookup/:stateId
So my problem now is:
I have a list of results but not many different states, how can I make that async call (useEffect?) to make that lookup only once for different stateId? Right now, I can get it to work, but the request is made on every single mapping. I'm putting the Axio call in a utility function to try and reuse this across multiple pages doing similar things, but is that the "React" way? In AngularJS, we use the "|" filter to map the code to text.
Once I have that mapping id => string, I want to store it in cache so next one that needs to map it no longer make the http request. Right now, I put the "cache" in the application level context and use dispatch to update/add values to the cache. Is that more efficient? It appears if I do a language change, where I keep the language in the same application context state, the cache would be re-initialized, and I'm not sure what other things would reset that. In AngularJS, we used the $rootState to 'cache'.
Thanks for any pointers!
In a lookupUtil.js
const DoLookupEntry = async (entryId) => {
const lookupUrl = `/lookup/${entryId}`;
try {
const response = await Axios.get(looupUrl,);
return response.data;
} catch (expt) {
console.log('error [DoLookupEntry]:',expt);
}
}
In a formatUtils.js
const formatLookupValue = (entryId) => {
const appState = useContext(AppContext);
const appDispatch = useContext(DispatchContext);
const language = appState.language;
if (appState.lookupCache
&& appState.lookupCache[entryId]
&& appState.lookupCache[entryId][language]) {
// return cached value
const entry = appState.lookupCache[entryId][language];
return entry.translatedValue;
}
// DoLookup is async, but we are not, so we want to wait...
DoLookupEntry(entryId)
.then((entry) => { // try to save to cache when value returns
appDispatch({type: States.APP_UPDATE_LOOKUP_CACHE,
value:{language, entry}})
return entry.translatedValue;
});
}
And finally the results.js displaying the result along the line (trying formatLookupValue to map the id):
{searchState.pageResults.map((item) => {
return (
<tr>
<td><Link to={/getItem/item.id}>{item.title}</Link></td>
<td>{item.detail}</td>
<td>{formatLookupValue(item.stateId)}</td>
</tr>
)
})}
I am looking to fetch the data of collection named users which has documents with an id of logged-in users' uid. Further, these documents contain some data and a subCollection called posts.
which looks like -
So now, I need to fetch all four(4) of these documents along with the posts collection data together so that I can display it.
My approach -
( here I fetched the document ids - middle section of image IDs)
// Fetching Firestore Users Document IDs
const [userDocs, setUserDocs] = React.useState([]);
React.useEffect(() => {
try {
const data = firestore.collection('users')
.onSnapshot(snap => {
let docIDs = [];
snap.forEach(doc => {
docIDs.push({id: doc.id});
});
setUserDocs(docIDs);
})
}
catch(err) {
console.log(err);
}
}, [])
Now, I have tried to fetch the entire data using the following way (which isn't working)
// Fetching Firestore Posts Data
const [postData, setPostData] = useState([]);
React.useEffect(() => {
try {
userDocs.map(data => {
const data = firestore.collection('users/'+currentUser.uid+'/posts')
.onSnapshot(snap => {
let documents = [];
snap.forEach(doc => {
documents.push({...doc.data(), id: doc.id});
});
setPostData(documents);
})
})
}
catch(err) {
console.log(err);
}
}, [])
Finally, I should end up with postData array which I can map on my card component to render all posted images and captions to the UI.
I am not sure if this is the right way to achieve what I am doing here, please help me correct this error and if there's a more subtle and easy way to do it please let me know. Thank You.
I have tried to fetch the entire data
Looking at the code you wrote for fetching "the entire data" (i.e. the second snippet) it seems that you don't need to link a post document to the parent user document when fetching the post documents. In other words, I understand that you want to fetch all the posts collection independently of the user documents.
Therefore you could use a Collection Group query.
If you need, for each post document returned by the Collection Group query, to get the parent user doc (for example to display the author name) you can do as explained in this SO answer, i.e. using the parent properties.
I've been trying to save data from my form in my MongoDB for some time.
I also get a response from the database.
See also: create object in mongo db api onclick sending form
Unfortunately there are not enough tutorials in my mother tongue and I don't seem to understand everything in English.
I've tried some of the documentation, but I always fail.
What is missing in my webhook function so that the form data can be stored?
exports = function(payload) {
const mongodb = context.services.get("mongodb-atlas");
const mycollection = mongodb.db("created_notifications").collection("dpvn_collection");
return mycollection.find({}).limit(10).toArray();
};
The Webhookfunction was totally wrong.
READ THE DOCUMENTATION FIRST
exports = function(payload, response) {
const mongodb = context.services.get("mongodb-atlas");
const requestLogs = mongodb.db("created_notifications").collection("dpvn_collection");
requestLogs.insertOne({
body: EJSON.parse(payload.body.text()),
query: payload.query
}).then(result => {
})
};
I am performing the search functionality in react native but i am getting an issue with sending the array of locations in link. My link is looking like this...
https://....listing/get_freelancers?listing_type=search&location=australia,england,united-emirates,united-kingdom
This is what i am getting comma seprated values in my link but i need this type of URL..
http://...search-freelancers/?keyword=&location%5B%5D=australia&location%5B%5D=canada
In this URL i have Array of locations i don't want comma separated values i need URL like this... here is my code where i am passing array in my URL...
fetchFreelancerData = async () => {
const { params } = this.props.navigation.state;
const response = await fetch(
BaseUrl+"listing/get_freelancers?
listing_type=search&location="+params.projectLocationKnown
);
const json = await response.json();
this.setState({ fetchFreelancer: json });
console.log( params.projectLocationKnown );
console.log( BaseUrl+"listing/get_freelancers?listing_type=search&profile_id=&keyword="+params.title+"&skills="+params.SkillsKnown+"&location="+params.projectLocationKnown+"&type="+params.freelancerLevelKnown+"&english_level="+params.englishKnown+"&language="+params.LangKnown );
};
In this patch of code i am getting values from another component and passing these array values in my fetch call here... please help about how to make the URL properly to fetch response.
You can try using encodeURIComponent(url) where url is the string containing the url you need to convert
In my react App I have a input element. The search query should be memoized, which means that if the user has previously searched for 'John' and the API has provided me valid results for that query, then next time when the user types 'Joh', there should be suggestion for the user with the previously memoized values(in this case 'John' would be suggested).
I am new to react and am trying caching for the first time.I read a few articles but couldn't implement the desired functionality.
You don't clarify which API you're using nor which stack; the solution would vary somewhat depending on if you are using XHR requests or something over GraphQL.
For an asynchronous XHR request to some backend API, I would do something like the example below.
Query the API for the search term
_queryUserXHR = (searchTxt) => {
jQuery.ajax({
type: "GET",
url: url,
data: searchTxt,
success: (data) => {
this.setState({previousQueries: this.state.previousQueries.concat([searchTxt])
}
});
}
You would run this function whenever you want to do the check against your API. If the API can find the search string you query, then insert that data into a local state array variable (previousQueries in my example).
You can either return the data to be inserted from the database if there are unknowns to your view (e.g database id). Above I just insert the searchTxt which is what we send in to the function based on what the user typed in the input-field. The choice is yours here.
Get suggestions for previously searched terms
I would start by adding an input field that runs a function on the onKeyPress event:
<input type="text" onKeyPress={this._getSuggestions} />
then the function would be something like:
_getSuggestions = (e) => {
let inputValue = e.target.value;
let {previousQueries} = this.state;
let results = [];
previousQueries.forEach((q) => {
if (q.toString().indexOf(inputValue)>-1) {
result.push(a);
}
}
this.setState({suggestions: results});
}
Then you can output this.state.suggestions somewhere and add behavior there. Perhaps some keyboard navigation or something. There are many different ways to implement how the results are displayed and how you would select one.
Note: I haven't tested the code above
I guess you have somewhere a function that queries the server, such as
const queryServer = function(queryString) {
/* access the server */
}
The trick would be to memorize this core function only, so that your UI thinks its actually accessing the server.
In javascript it is very easy to implement your own memorization decorator, but you could use existing ones. For example, lru-memoize looks popular on npm. You use it this way:
const memoize = require('lru-memoize')
const queryServer_memoized = memoize(100)(queryServer)
This code keeps in memory the last 100 request results. Next, in your code, you call queryServer_memoized instead of queryServer.
You can create a memoization function:
const memo = (callback) => {
// We will save the key-value pairs in the following variable. It will be our cache storage
const cache = new Map();
return (...args) => {
// The key will be used to identify the different arguments combination. Same arguments means same key
const key = JSON.stringify(args);
// If the cache storage has the key we are looking for, return the previously stored value
if (cache.has(key)) return cache.get(key);
// If the key is new, call the function (in this case fetch)
const value = callback(...args);
// And save the new key-value pair to the cache
cache.set(key, value);
return value;
};
};
const memoizedFetch = memo(fetch);
This memo function will act like a key-value cache. If the params (in our case the URL) of the function (fetch) are the same, the function will not be executed. Instead, the previous result will be returned.
So you can just use this memoized version memoizedFetch in your useEffect to make sure network request are not repeated for that particular petition.
For example you can do:
// Place this outside your react element
const memoizedFetchJson = memo((...args) => fetch(...args).then(res => res.json()));
useEffect(() => {
memoizedFetchJson(`https://pokeapi.co/api/v2/pokemon/${pokemon}/`)
.then(response => {
setPokemonData(response);
})
.catch(error => {
console.error(error);
});
}, [pokemon]);
Demo integrated in React