RxJS subscribe inside subscribe with each level returns values and store into respective variables

Question

I know already there are posts regarding the Nested Subscribe. Here, we have 5 leveled subscribeoperation with each variables (operationId,actionlistId,componentId,traceId). Her

Answer 1

Your code looks correct. So you need to figure out what part of code gets so many time. I suggest you to use performance.now() method to measure your code:

console.log(`1. performance.now() ${performance.now()}`);
this.ordertemplateService.GetOperationTemplate(this.orderTemplateId)
.pipe(
switchMap((opData)=> {        
    console.log(`2. performance.now() ${performance.now()}`);
    }),
switchMap((actData)=> {
    console.log('ActionList');

switchMap((cmpData)=> {
    console.log(`3. performance.now() ${performance.now()}`);
    this.componentModel = this.ordertemplateService.GetComponentUsageTemplate(this.actionModel[0].id); // cmpData[0].id
    this.componentId = this.componentModel[0].id;
    if (Object.keys(this.componentModel).length > 0) {
                  console.log(this.componentModel);
                  console.log('Component Usage');
    } else {
                this.initializeComponentTrace();
            }       
    console.log(`4. performance.now() ${performance.now()}`);
    }),
switchMap((traceData)=> {
    console.log(`5. performance.now() ${performance.now()}`);
    this.traceModel = this.ordertemplateService.GetTraceTemplate(this.componentModel[0].parentId); // cmpData[0].id
            if (Object.keys(this.traceModel).length > 0) {
                 this.traceId = this.traceModel[0].id;
                 console.log(this.traceModel);
                 console.log('Trace Usage')
     } else {
                 this.initializeTrace();
             }

    console.log(`6. performance.now() ${performance.now()}`);
}))
.subscribe((data)=> {
    if(data!= undefined) {
    console.log(data);
    console.log(`7. performance.now() ${performance.now()}`);
    }
})

Then you will have an iformation, what piece of code is takes so many time.