ERROR undefined, HttpErrorResponse {headers: HttpHeaders, status: 404, statusText: "Not Found" - http

i have a little worry, if some can just help me, i use a laravel 5.8 api, which i create, when i retrieve the parameter data mtr from posteman its walk, but when i do the same thing with this url << url = 'http://127.0.0.1:8000/api/studentbyid/45' >> it works its problem because the 45 is the mtr, whereas according to the logic that I try to put in place and that it is the user who will introduce the mtr, then display...
import { Component, OnInit } from '#angular/core';
import { HttpClient } from '#angular/common/http';
import { Candidate } from '../models/candidate';
#Component({
selector: 'app-candidate',
templateUrl: './candidate.page.html',
styleUrls: ['./candidate.page.scss'],
})
export class CandidatePage implements OnInit {
mtr: '45';
// tslint:disable-next-line: new-parens
data: any;
url = 'http://127.0.0.1:8000/api/studentbyid/';
constructor( private httpClient: HttpClient) { }
ionViewWillEnter(mtr: string) {
return this.httpClient.get(this.url + '/' + this.mtr)
.subscribe(
data => {
this.data = JSON.stringify(data);
console.log(this.data);
},
error => {
console.log(error);
});
}
ngOnInit() {}
getbyID( mtr: string) {}
}
here is the result in the console when I place it directly
enter image description here
and that's when I try to retrieve the word from a userenter image description here
if there are some who can just help me, and I notice that there is no answer in the form of object

Your variable mtr is indeed undefined.
mtr: '45';
console.log(mtr);
// undefined
You need to set the variable to the '45' string instead you typed the mtrvariable as type '45'.
mtr: string = '45';
console.log(mtr);
// '45'

Related

Return firebase values from a service to a component angular 6

I'm creating an application with angular 6 and firebase using angularfire2, I chose to use the firestore where I have a collection called pages like in the image:
basically I created a service - "PagesService" where I have a function that returns the data of the page that I sent. I'm trying to use getPage to return the values to my component, and assign them to the form, nothing else I tried worked, only returns an "observable" that I can not work, does anyone have an idea of what I can do?
Full code, service:
import { Injectable } from '#angular/core';
import { AngularFirestore, AngularFirestoreCollection, AngularFirestoreDocument } from 'angularfire2/firestore';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';
#Injectable()
export class PagesService {
private pagesCollection: AngularFirestoreCollection<any>;
private page: AngularFirestoreDocument<any>;
constructor(private afs: AngularFirestore) {
this.pagesCollection = afs.collection('pages');
}
getPage(pageName: string) {
return this.afs.doc<any>('pages/${pageName}').valueChanges();
}
addPages(pageName: string, pageForm: any) {
this.pagesCollection.doc(pageName).set(pageForm.value);
}
}
My component:
import { Component, OnInit } from '#angular/core';
import { FormBuilder, FormGroup } from '#angular/forms';
import { Observable } from 'rxjs';
import { PagesService } from '../../services/pages.service';
#Component({
selector: 'app-quem-somos',
templateUrl: './quem-somos.component.html',
styleUrls: ['./quem-somos.component.scss']
})
export class QuemSomosComponent implements OnInit {
pageForm: FormGroup;
pageName: string = "wo-we-are";
page: any;
constructor(private pagesService: PagesService, private fb: FormBuilder) { }
ngOnInit() {
this.page = this.pagesService.getPage(this.pageName);
console.log(this.page);
this.pageForm = this.fb.group({
title: '',
content: ''
});
}
save() {
this.pagesService.addPages(this.pageName, this.pageForm);
}
}
obs: Sorry my english
If I have understand you right, When you say "Observable that I cannot work" is mean that you cannot access his data when you are trying to assign its values in the form?
In this case (I assume that your service is working as expected), just subscribe to it and populate the form after your values are ready to use. for example:
ngOnInit() {
this.pagesService.getPage(this.pageName).subscribe(v => {
// Here your data is ready, so you can send it to a function and populate the form as you need.
this.populateForm(v);
});
// Here I just construct the FormGroup, so your application can rendered.
this.pageForm = this.fb.group({
title: '',
content: ''
});
}
And add this function to do the task:
populateForm = (data) => {
console.log(data); // Just log it in console, and see if its the data that you seek for
}
Instead of console.log() you can populate your form or do what ever you need to.
Good Luck !
--EDIT--
I just noticed now, In your service:
getPage(pageName: string) {
return this.afs.doc<any>('pages/${pageName}').valueChanges();
}
You call the doc with ' ' instead of ``, so In fact, you are not using Template Strings. So your call is wrong and not fetch with the right path.
Change it to:
return this.afs.doc<any>(`pages/${pageName}`).valueChanges();

Angular2 - unable to retrieve data from API

I am currently building an Angular2 application accessing an MVC web API i have built. However, it does not seem to retrieve any data. I am obviously missing something but i am not sure what.
I know that the URL i am using works along with the headers as i am able to retrieve the data correctly through fiddler.
My repack.service.ts is as follows:
import { Injectable } from '#angular/core';
import { Headers, Http } from '#angular/http';
import 'rxjs/add/operator/toPromise';
import { RepackIndex } from './RepackIndex';
#Injectable()
export class RepackService{
private baseUrl = 'https://localhost:44321/api/Repack/All';
private headers = new Headers({'Content-Type': 'application/json'});
constructor(private http: Http) { }
getAllRepacks(): Promise<RepackIndex[]>{
var data = this.http.get(this.baseUrl)
.toPromise()
.then(response => response.json().data as RepackIndex[])
.catch(this.handleError);
return data;
}
private handleError(error: any): Promise<any>{
console.error("An error occured in repack.service", error);
return Promise.reject(error.message || error);
}
}
And this is my component:
import { Component, OnInit } from '#angular/core';
import { Router } from '#angular/router';
import { RepackIndex } from './repackIndex';
import { RepackService } from './repack.service';
#Component({
selector: 'index',
templateUrl: 'app/index.component.html',
providers: [RepackService]
})
export class IndexComponent implements OnInit{
repacks: RepackIndex[];
selectedRepack: RepackIndex;
constructor(private router: Router, private repackService: RepackService) { }
onSelect(repack: RepackIndex): void{
this.selectedRepack = repack;
}
getRepacks(): void{
this.repackService.getAllRepacks().then(repacks => this.repacks = repacks);
}
ngOnInit(): void{
this.getRepacks();
}
}
I have tried putting in a breakpoint and adding a console.log line but no data is returned to the component.
I am fairly new to Angular2 so any help would be greatly appreciated.
Thanks,
Right I have managed to get it to work by using an observable rather than a promise.
My service method now looks like this:
public GetAll = (): Observable<RepackIndex[]> => {
return this.http.get(this.baseUrl)
.map((response: Response) => <RepackIndex[]>response.json())
.catch(this.handleError);
}
And my Component call now looks like this:
getRepacks(): void{
this.repackService.GetAll()
.subscribe((data:RepackIndex[]) => this.repacks = data,
error => console.log(error),
() => console.log('Get All repacks complete'));
}
I found the answer here
Hope this helps someone else

ViewWrappedExcepetion error is null, then not null

I'm starting with angular2. And I try to get data from an php script.
I followed the turorial at the angular docs. But I recently get this confusing error messeage:
zone.js:463 ViewWrappedException {_wrapperMessage: "Error in app/components/catch-data/catch-data.component.html:7:5", _originalException: TypeError: Cannot read property 'name' of undefined
at DebugAppView._View_CatchDataComponent0.de…, _originalStack: "TypeError: Cannot read property 'name' of undefine…t/node_modules/#angular/core/core.umd.js:9996:18)", _context: DebugContext, _wrapperStack: "Error: Error in app/components/catch-data/catch-da…tChangesInternal (AppComponent.template.js:121:8)"}
containing this message:
TypeError: Cannot read property 'name' of undefined
at DebugAppView._View_CatchDataComponent0.detectChangesInternal (CatchDataComponent.template.js:62)
at DebugAppView.AppView.detectChanges (core.umd.js:9996)
at DebugAppView.detectChanges (core.umd.js:10084)
at DebugAppView.AppView.detectViewChildrenChanges (core.umd.js:10016)
at DebugAppView._View_CatchDataComponent_Host0.detectChangesInternal (CatchDataComponent_Host.template.js:36)
at DebugAppView.AppView.detectChanges (core.umd.js:9996)
at DebugAppView.detectChanges (core.umd.js:10084)
at DebugAppView.AppView.detectContentChildrenChanges (core.umd.js:10011)
at DebugAppView._View_AppComponent0.detectChangesInternal (AppComponent.template.js:121)
at DebugAppView.AppView.detectChanges (core.umd.js:9996)
I have no idea where this error comes from. Here is my code:
model.service.ts
import { Injectable } from '#angular/core';
import { Http, Headers } from '#angular/http';
import { Model } from '../../class/model/model';
#Injectable()
export class ModelService
{
constructor(private http: Http){}
private modelUrl = '../../server/clientFunc/getModel.php';
getModel (): Promise<Model> {
return this.http.get(this.modelUrl).toPromise().then(response => response.json()).catch(this.handleError);
}
private handleError(error: any) {
console.error('An error occurred', error);
return Promise.reject(error.message || error);
}
}
catch-data.component.ts
import { Component, OnInit } from '#angular/core';
import { Router } from '#angular/router-deprecated';
import {Model} from '../../class/model/model';
import {ModelService} from '../../services/model/model.service';
#Component({
selector: 'catch-data',
templateUrl: 'app/components/catch-data/catch-data.component.html',
providers: [ModelService]
})
export class CatchDataComponent implements OnInit
{
constructor(private modelService:ModelService) {
}
model:Model;
errorMessage:string;
testItem = "Test-Item";
ngOnInit():any {
this.getModel();
}
getModel() {
this.modelService.getModel()
.then(response => {
this.model = new Model();
this.model.deserialize(response);
})
.catch(error => {
this.errorMessage = error;
console.log(error);
}); // TODO: Display
}
}
and the model.ts
export class Model
{
id:number;
name:string;
constructor(){
}
deserialize(object){
this.name = object.name;
this.id = object.id;
}
}
The template looks like:
<h1>Search and catch data</h1>
<h3>Model: {{testItem}}</h3>
<div>Name: {{model.name}}</div>
So as I could detect the CatchDataComponent gets null as I call getModel().
So in ngOnInit this is not null but a call later in getModel() this is null.
I have no Idea why this happens.
I hope you have an idea or any suggestions.
I think that you could use the Elvis operator:
<div>Name: {{model?.name}}</div>
because the model property is loaded asynchronously and not available when the model.name is evaluated at first...

Fill form after http response in angular2

I'm wondering what is a best way to load a form after getting the response from server. I wrote some code where it is getting data from server and in my component I am subscribing to the response, but My UI is loading before even I get the response.
I want to use this component for both adding and editing.
Component:
#Component({
selector: 'gate',
templateUrl: '/public/app/views/gate.html',
directives: [GateFormComponent, StrategyComponent],
providers : [MyService]
})
export class MyComponent {
private id:any;
constructor(private _routeParams:RouteParams, #Inject(MyModel) private myModel,
private myService : MyService) {
}
ngOnInit() {
this.id = this._routeParams.get("id");
if (this.id) {
this.gateDataModel.unique_display_id = parseInt(this.id);
this.myService.loadData(this.id)
.subscribe(response => console.log(response));
}
}
In my component, I am loading 2 components one of which has a form into which I have to load data once I get the response. And all this should only happen if I have an id available.
Service:
#Injectable()
export class MyService extends HTTPServices {
constructor(http:Http) {
super(http);
}
loadData(id:number) {
return this.query(url)
.map(res => res.json())
.catch(this.handleError)
}
private handleError(error:Response) {
console.log("Error : ", error);
return Observable.throw(error.text());
}
HTTPServices
export class HTTPServices {
private headers:Headers;
private http:Http;
defaultOptionsArgs:RequestOptionsArgs;
constructor(http:Http) {
this.http = http;
this.headers = new Headers();
this.headers.append('Content-Type', 'application/json');
this.defaultOptionsArgs = {
'headers': this.headers
};
}
create(servicePath:string, model:any, options?:RequestOptionsArgs) {
var url = this.getUrl(servicePath);
var options = options ? options : this.defaultOptionsArgs;
return this.http.post(url, JSON.stringify(model), options);
}
query(servicePath:string, options?:RequestOptionsArgs) {
var options = options ? options : this.defaultOptionsArgs;
return this.http.get(servicePath, options);
}
}
----Edited-----
Finally, I was able to add #CanActivate and it is working.
#Component({
selector: 'gate',
templateUrl: '/public/app/views/gate.html',
directives: [ROUTER_DIRECTIVES, GateFormComponent, StrategyComponent]
})
#CanActivate(
(next: ComponentInstruction, prev: ComponentInstruction) => {
return new Promise((resolve) => {
let id = next.params["id"];
let injector = ReflectiveInjector.resolveAndCreate([HTTP_PROVIDERS]);
let http = injector.get(Http);
if(id){
http.get(URL)
.subscribe((response) => {
console.log(response)
next.routeData.data["response"] = response;
// continue
resolve(true);
}, (error) => {
resolve(false);
});
} else {
resolve(true);
}
});
}
)
export class MyComponent{
private id:any;
constructor(private _routeParams:RouteParams, #Inject(MyModel) private myModel, routeData: RouteData) {
console.log(routeData.get("response"));
}
}
The component is loading up and then I am getting the response
Thanks
In you component you can just use
template: `
<div *ngIf="data">
<!-- form goes here -->
</div>
`
where data is a property that is set to some value when the response from the server arrived.
If you leverage Angular2 routing (and it seems to be the case), you could use leverage the OnActivate interface and its routerOnActivate:
Defines route lifecycle method routerOnActivate, which is called by the router at the end of a successful route navigation.
For a single component's navigation, only one of either OnActivate or OnReuse will be called depending on the result of CanReuse.
The routerOnActivate hook is called with two ComponentInstructions as parameters, the first representing the current route being navigated to, and the second parameter representing the previous route or null.
If routerOnActivate returns a promise, the route change will wait until the promise settles to instantiate and activate child components.
You could return a promise that will be resolved when your data will be there. Here is a sample:
#Component({ ... })
export class MyComponent {
private id:any;
constructor(private _routeParams:RouteParams,
#Inject(MyModel) private myModel,
private myService : MyService) {
}
routerOnActivate() {
this.id = this._routeParams.get("id");
return new Promise((resolve, reject) => {
if (this.id) {
this.gateDataModel.unique_display_id = parseInt(this.id);
this.myService.loadData(this.id)
.subscribe(response => {
console.log(response);
resolve();
});
} else {
resolve();
}
});
}
(...)
}
I had a similar question, but since the solution can be used for your usecase too, i would recommend to have a look at the accepted answer: How to manipulate a component on specific routes in Angular2
The basic idea is to extend the router-outlet directive and override the activate() function which will be called before the next route is activated and waits for a promise to resolve.
For example you could do something like this:
#Directive({
selector: 'custom-router-outlet'
})
export class CustomRouterOutlet extends RouterOutlet {
private parentRouter:Router;
constructor(_elementRef: ElementRef,
_loader: DynamicComponentLoader,
_parentRouter: Router,
#Attribute('name') nameAttr: string,
private _myRoutingService:MyRoutingService) {
super(_elementRef, _loader, _parentRouter, nameAttr);
this.parentRouter = _parentRouter;
}
activate(nextInstruction: ComponentInstruction): Promise<any> {
let someRouteSpecificData = nextInstruction.routeData.data['someRouteData'];
if(someRouteSpecificData) {
_myRoutingService.beforeRoute(someRouteSpecificData).subscribe( () => {
// go on after this has been resolved
return super.activate(nextInstruction);
// or maybe cancel the route:
return false;
// or maybe do something crazy:
nextInstruction.componentType = MyOtherComponent;
return super.activate(nextInstruction);
}
}
return super.activate(nextInstruction);
}
}
I think you could easily change this for your purposes. You could utilize your #RouteConfig for example to hold some information on what should happen or be checked on a route change.
Another approach would be to use the #CanActivate decorator like mentioned here already, but its a bit harder to accomplish. It just feels a bit hacky at this point. I could add this later if you're interested.
I have been able to implement this using the resolve functions of the router (https://angular.io/docs/ts/latest/guide/router.html#!#resolve-guard). This enables the http calls to be made and the route only completes when the http call observable returns.
There are good examples here: https://angular.io/resources/live-examples/router/ts/plnkr.html

Data communication in Angular2

I'trying to use the HTTP service in Angular2 and i have some concerns.
I'm taking meteo datas from openweather API and I just want to put it inside a typeScript variable (meteo: {}) and use it as i want in my template.
Here are my .ts files:
meteo.service.ts
import {Injectable} from "angular2/core";
import {Http, Response} from "angular2/http";
import {Observable} from "rxjs/Observable";
import {MeteoComponent} from "../widgets/meteo/meteo.component";
import {Meteo} from "../widgets/meteo/meteo";
#Injectable()
export class MeteoService {
constructor(private http: Http) {}
// Nom de la ville sans accent
private _ville = 'Montreal';
// Initiales du pays
private _country = 'ca';
// Units (metric/imperial)
private _units = 'metric';
// API KEY
private _APPID = 'ewfw54f5646';
// url to get data
private _meteoUrl = 'http://api.openweathermap.org/data/2.5/weather?q='+this._ville+','+this._country+'&units='+this._units+'&APPID='+this._APPID;
getMeteo (): Observable<Meteo> {
return this.http.get(this._meteoUrl)
.map(this.extractData)
.catch(this.handleError);
}
private extractData(res: Response) {
if(res.status < 200 || res.status >= 300) {
throw new Error('Bad response status: ' + res.status);
}
let body = res.json();
return body || { };
}
private handleError(error: any) {
let errMsg = error.message || 'server error';
console.error(errMsg);
return Observable.throw(errMsg);
}
}
meteo.component.ts
import {Component, OnInit, OnChanges, AfterContentInit} from "angular2/core";
import {MeteoService} from "../../services/meteo.service";
import {Meteo} from "./meteo";
#Component({
selector: 'meteo',
templateUrl: 'dev/widgets/meteo/meteo.component.html',
providers: [MeteoService]
})
export class MeteoComponent implements OnInit {
errorMessage: string;
meteo: Meteo;
// We inject the service into the constructor
constructor (private _meteoService: MeteoService) {}
// Instantiate data in the ngOnInit function to keep the constructor simple
ngOnInit() {
this.getMeteo();
}
getMeteo() {
this._meteoService.getMeteo()
.subscribe(
data => this.meteo = data,
error => this.errorMessage = <any>error);
}
}
meteo.ts
export class Meteo {
data: {};
}
and meteo.component.html
<span class="meteo">{{meteo | json}}°C</span>
Actually the result is the entire json object:
{
"coord": {
"lon":-73.59,
"lat":45.51
},
"weather":[
{
"id":803,
"main":"Clouds",
"description":"broken clouds",
"icon":"04d"
}
],
"base":"cmc stations",
"main":{
"temp":3.96,
"pressure":1020,
"humidity":32,
"temp_min":2,
"temp_max":6.67
},
"wind":{
"speed":2.1
},
"clouds":{
"all":75
},
"dt":1461594860,
"sys":{
"type":1,
"id":3829,
"message":0.004,
"country":"CA",
"sunrise":1461577807,
"sunset":1461628497
},
"id":6077243,
"name":"Montreal",
"cod":200
}
And I would like to display just the temp field.
If you have any idea guys it's welcomed!
Thanks a lot.
You could leverage the Elvis operator since your data are loaded asynchronously:
<span class="meteo">{{meteo?.main.temp | json}}°C</span>
Try setting the data on this.meteo.data
getMeteo() {
this._meteoService.getMeteo()
.subscribe(
data => this.meteo.data = data,
error => this.errorMessage = <any>error);
}
and then displaying it with
<span class="meteo">{{meteo.data.main.temp}}°C</span>

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