Standard practice to define HttpHeaders()? One common function to define new HttpHeaders() or should it be define under each function?

Question

What is the standard practice to set custom headers in Angular?

To have a global setHeader function in a service file, where every get request calls this function

app.component.ts

 getData() {
        const url = `myurl`;
        var param = {"data1": this.data1,"data2": this.data2}
        var headerObj = {"header1": this.header1,"header2": this.header2,}
        this.dataService.getRequest(url, param, headerObj)
            .subscribe((data) => {});
    }

dataService.ts

setHeaders(header) {
    var httpHeaders = new HttpHeaders();
    header.forEach((key, value) => {
        httpHeaders = httpHeaders.append(key, value);
    });
    return httpHeaders
}
getRequest(endPoint: String, param: any, header: any) {
    const httpHeaders = this.setHeaders(header);
    return this.http.get<any>(url, {
        headers: httpHeaders,
        params: param
    })
}

OR Passing header from app.component function into dataService.ts get request function

app.component.ts

getData() {
    const url = `myurl`;
    var param = {"data1": this.data1,"data2": this.data2,}
    let headers = new HttpHeaders()
    .set('header1', this.header1)
    .set('header2', this.header2);
    this.dataService.getRequest(url, param, headers)
    .subscribe((data) => {});
}

dataService.ts

getRequest(endPoint: string, params: any, headers: HttpHeaders) {
    return this.http.get<any>(endPoint, {
        headers: headers,
        params: param
    })
}