finishing pagination for medical history page.

backend/pkg/database/interface.go

@@ -28,7 +28,7 @@ type DatabaseRepository interface {
 	AddResourceAssociation(ctx context.Context, source *models.SourceCredential, resourceType string, resourceId string, relatedSource *models.SourceCredential, relatedResourceType string, relatedResourceId string) error
 	RemoveResourceAssociation(ctx context.Context, source *models.SourceCredential, resourceType string, resourceId string, relatedSource *models.SourceCredential, relatedResourceType string, relatedResourceId string) error
 	FindResourceAssociationsByTypeAndId(ctx context.Context, source *models.SourceCredential, resourceType string, resourceId string) ([]models.RelatedResource, error)
-	GetFlattenedResourceGraph(ctx context.Context, graphType pkg.ResourceGraphType, options models.ResourceGraphOptions) (map[string][]*models.ResourceBase, error)
+	GetFlattenedResourceGraph(ctx context.Context, graphType pkg.ResourceGraphType, options models.ResourceGraphOptions) (map[string][]*models.ResourceBase, *models.ResourceGraphMetadata, error)
 	AddResourceComposition(ctx context.Context, compositionTitle string, resources []*models.ResourceBase) error
 	//UpsertProfile(context.Context, *models.Profile) error
 	//UpsertOrganziation(context.Context, *models.Organization) error

backend/pkg/database/sqlite_repository_graph.go

@@ -28,10 +28,17 @@ func (rp *VertexResourcePlaceholder) ID() string {
 // Retrieve a list of all fhir resources (vertex), and a list of all associations (edge)
 // Generate a graph
 // return list of root nodes, and their flattened related resources.
-func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graphType pkg.ResourceGraphType, options models.ResourceGraphOptions) (map[string][]*models.ResourceBase, error) {
+func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graphType pkg.ResourceGraphType, options models.ResourceGraphOptions) (map[string][]*models.ResourceBase, *models.ResourceGraphMetadata, error) {
 	currentUser, currentUserErr := sr.GetCurrentUser(ctx)
 	if currentUserErr != nil {
-		return nil, currentUserErr
+		return nil, nil, currentUserErr
+	}
+
+	//initialize the graph results metadata
+	resourceGraphMetadata := models.ResourceGraphMetadata{
+		TotalElements: 0,
+		PageSize:      20, //TODO: replace this with pkg.DefaultPageSize
+		Page:          options.Page,
 	}
 
 	// Get list of all (non-reciprocal) relationships
@@ -44,7 +51,7 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 		}).
 		Find(&relatedResourceRelationships)
 	if result.Error != nil {
-		return nil, result.Error
+		return nil, nil, result.Error
 	}
 
 	//Generate Graph
@@ -97,7 +104,7 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 			&resourcePlaceholder,
 		)
 		if err != nil {
-			return nil, fmt.Errorf("an error occurred while adding vertex: %v", err)
+			return nil, nil, fmt.Errorf("an error occurred while adding vertex: %v", err)
 		}
 	}
 
@@ -134,7 +141,7 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 	//	}
 	adjacencyMap, err := g.AdjacencyMap()
 	if err != nil {
-		return nil, fmt.Errorf("error while generating AdjacencyMap: %v", err)
+		return nil, nil, fmt.Errorf("error while generating AdjacencyMap: %v", err)
 	}
 
 	// For a directed graph, PredecessorMap is the complement of AdjacencyMap. This is because in a directed graph, only
@@ -143,7 +150,7 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 	// ie. "empty" verticies in this map are "root" nodes.
 	predecessorMap, err := g.PredecessorMap()
 	if err != nil {
-		return nil, fmt.Errorf("error while generating PredecessorMap: %v", err)
+		return nil, nil, fmt.Errorf("error while generating PredecessorMap: %v", err)
 	}
 
 	// Doing this in one massive function, because passing graph by reference is difficult due to generics.
@@ -193,10 +200,11 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 	// Step 2: now that we've created a relationship graph using placeholders, we need to determine which page of resources to return
 	// and look up the actual resources from the database.
 
-	resourceListDictionary, err := sr.InflateResourceGraphAtPage(resourcePlaceholderListDictionary, options.Page)
+	resourceListDictionary, totalElements, err := sr.InflateResourceGraphAtPage(resourcePlaceholderListDictionary, options.Page)
 	if err != nil {
-		return nil, fmt.Errorf("error while paginating & inflating resource graph: %v", err)
+		return nil, nil, fmt.Errorf("error while paginating & inflating resource graph: %v", err)
 	}
+	resourceGraphMetadata.TotalElements = totalElements
 
 	// Step 3: define a function. When given a resource, should find all related resources, flatten the heirarchy and set the RelatedResourceFhir list
 	flattenRelatedResourcesFn := func(resource *models.ResourceBase) {
@@ -279,7 +287,7 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 
 	// Step 5: return the populated resource list dictionary
 
-	return resourceListDictionary, nil
+	return resourceListDictionary, &resourceGraphMetadata, nil
 }
 
 // LoadResourceGraphAtPage - this function will take a dictionary of placeholder "sources" graph and load the actual resources from the database, for a specific page
@@ -287,7 +295,8 @@ func (sr *SqliteRepository) GetFlattenedResourceGraph(ctx context.Context, graph
 // - sort the root resources by date, desc
 // - use the page number + page size to determine which root resources to return
 // - return a dictionary of "source" resource lists
-func (sr *SqliteRepository) InflateResourceGraphAtPage(resourcePlaceholderListDictionary map[string][]*VertexResourcePlaceholder, page int) (map[string][]*models.ResourceBase, error) {
+func (sr *SqliteRepository) InflateResourceGraphAtPage(resourcePlaceholderListDictionary map[string][]*VertexResourcePlaceholder, page int) (map[string][]*models.ResourceBase, int, error) {
+	totalElements := 0
 	// Step 3a: since we cant calulate the sort order until the resources are loaded, we need to load all the root resources first.
 
 	//TODO: maybe its more performant to query each resource by type/id/source, since they are indexed already?
@@ -307,7 +316,7 @@ func (sr *SqliteRepository) InflateResourceGraphAtPage(resourcePlaceholderListDi
 
 		tableName, err := databaseModel.GetTableNameByResourceType(resourceType)
 		if err != nil {
-			return nil, err
+			return nil, totalElements, err
 		}
 		var tableWrappedResourceModels []models.ResourceBase
 		sr.GormClient.
@@ -322,6 +331,9 @@ func (sr *SqliteRepository) InflateResourceGraphAtPage(resourcePlaceholderListDi
 	//sort
 	rootWrappedResourceModels = utils.SortResourceListByDate(rootWrappedResourceModels)
 
+	//calculate total elements
+	totalElements = len(rootWrappedResourceModels)
+
 	//paginate (by calculating window for the slice)
 	rootWrappedResourceModels = utils.PaginateResourceList(rootWrappedResourceModels, page, 20) //todo: replace size with pkg.ResourceListPageSize
 
@@ -336,7 +348,7 @@ func (sr *SqliteRepository) InflateResourceGraphAtPage(resourcePlaceholderListDi
 	}
 
 	// Step 4: return the populated resource list dictionary
-	return resourceListDictionary, nil
+	return resourceListDictionary, totalElements, nil
 }
 
 //We need to support the following types of graphs:

backend/pkg/models/resource_graph_metadata.go

@@ -0,0 +1,7 @@
+package models
+
+type ResourceGraphMetadata struct {
+	TotalElements int `json:"total_elements"`
+	PageSize      int `json:"page_size"`
+	Page          int `json:"page"`
+}

backend/pkg/web/handler/resource_fhir.go

@@ -140,12 +140,15 @@ func GetResourceFhirGraph(c *gin.Context) {
 		graphOptions.Page = pageNumb
 	}
 
-	resourceListDictionary, err := databaseRepo.GetFlattenedResourceGraph(c, pkg.ResourceGraphType(graphType), graphOptions)
+	resourceListDictionary, resourceListMetadata, err := databaseRepo.GetFlattenedResourceGraph(c, pkg.ResourceGraphType(graphType), graphOptions)
 	if err != nil {
 		logger.Errorln("An error occurred while retrieving list of resources", err)
 		c.JSON(http.StatusInternalServerError, gin.H{"success": false})
 		return
 	}
 
-	c.JSON(http.StatusOK, gin.H{"success": true, "data": resourceListDictionary})
+	c.JSON(http.StatusOK, gin.H{"success": true, "data": map[string]interface{}{
+		"results":  resourceListDictionary,
+		"metadata": resourceListMetadata,
+	}})
 }

frontend/src/app/models/fasten/resource-graph-response.ts

@@ -0,0 +1,12 @@
+import {ResourceFhir} from './resource_fhir';
+
+export class ResourceGraphResponse {
+  results: {[resource_type: string]: ResourceFhir[]}
+  metadata: ResourceGraphMetadata
+}
+
+export class ResourceGraphMetadata {
+  total_elements: number
+  page_size: number
+  page: number
+}

frontend/src/app/pages/medical-history/medical-history.component.html

@@ -12,7 +12,7 @@
         <div class="row mt-5 mb-3">
           <div class="col-12">
 
-            <div class="alert alert-warning" role="alert">
+            <div [hidden]="true" class="alert alert-warning" role="alert">
               <strong>Warning!</strong> Fasten has detected medical Encounters that are not associated with a Condition.
               They are grouped under the "Unassigned" section below.
               <br/>
@@ -34,6 +34,13 @@
         <!-- Condition List -->
         <app-report-medical-history-condition *ngFor="let condition of conditions; let i = index" [conditionGroup]="condition"></app-report-medical-history-condition>
         <app-report-medical-history-explanation-of-benefit *ngFor="let eob of explanationOfBenefits; let i = index" [explanationOfBenefitGroup]="eob"></app-report-medical-history-explanation-of-benefit>
+
+        <ngb-pagination
+          *ngIf="resourceGraphMetadata.total_elements > resourceGraphMetadata.page_size"
+          [(page)]="resourceGraphMetadata.page"
+          (pageChange)="pageChange($event)"
+          [pageSize]="resourceGraphMetadata.page_size"
+          [collectionSize]="resourceGraphMetadata.total_elements"></ngb-pagination>
       </ng-template>
 
       <ng-template #emptyReport>

frontend/src/app/pages/medical-history/medical-history.component.ts

@@ -4,6 +4,7 @@ import {ResourceFhir} from '../../models/fasten/resource_fhir';
 import { ModalDismissReasons, NgbModal } from '@ng-bootstrap/ng-bootstrap';
 import {ReportMedicalHistoryEditorComponent} from '../../components/report-medical-history-editor/report-medical-history-editor.component';
 import {forkJoin} from 'rxjs';
+import {ResourceGraphMetadata, ResourceGraphResponse} from '../../models/fasten/resource-graph-response';
 // import {ReportEditorRelatedComponent} from '../../components/report-editor-related/report-editor-related.component';
 
 @Component({
@@ -21,6 +22,12 @@ export class MedicalHistoryComponent implements OnInit {
   unassigned_encounters: ResourceFhir[] = []
   resourceLookup: {[name: string]: ResourceFhir} = {}
 
+  resourceGraphMetadata: ResourceGraphMetadata = {
+    total_elements: 0,
+    page_size: 0,
+    page: 1
+  }
+
   constructor(
     private fastenApi: FastenApiService,
     private modalService: NgbModal
@@ -28,12 +35,21 @@ export class MedicalHistoryComponent implements OnInit {
 
 
   ngOnInit(): void {
+    //load the first page
+    this.pageChange(1)
+  }
+
+  pageChange(page: number){
     this.loading = true
-    this.fastenApi.getResourceGraph().subscribe(results => {
+    this.fastenApi.getResourceGraph(null, page).subscribe((response: ResourceGraphResponse) => {
       this.loading = false
-      this.conditions = [].concat(results["Condition"] || [], results["Composition"] || [])
-      this.unassigned_encounters = results["Encounter"] || []
-      this.explanationOfBenefits = results["ExplanationOfBenefit"] || []
+      this.resourceGraphMetadata = response.metadata
+      //page counter is 1 indexed but the backend is 0 indexed
+      this.resourceGraphMetadata.page = this.resourceGraphMetadata.page + 1
+
+      this.conditions = [].concat(response.results["Condition"] || [], response.results["Composition"] || [])
+      this.unassigned_encounters = response.results["Encounter"] || []
+      this.explanationOfBenefits = response.results["ExplanationOfBenefit"] || []
 
       //populate a lookup table with all resources
       for(let condition of this.conditions){
@@ -66,6 +82,7 @@ export class MedicalHistoryComponent implements OnInit {
 
   }
 
+
   openEditorRelated(): void {
     const modalRef = this.modalService.open(ReportMedicalHistoryEditorComponent, {
       size: 'xl',

frontend/src/app/services/fasten-api.service.ts

@@ -22,6 +22,7 @@ import * as fhirpath from 'fhirpath';
 import _ from 'lodash';
 import {DashboardConfig} from '../models/widget/dashboard-config';
 import {DashboardWidgetQuery} from '../models/widget/dashboard-widget-query';
+import {ResourceGraphResponse} from '../models/fasten/resource-graph-response';
 import { fetchEventSource } from '@microsoft/fetch-event-source';
 
 @Injectable({
@@ -178,16 +179,21 @@ export class FastenApiService {
     return this._httpClient.post<any>(`${GetEndpointAbsolutePath(globalThis.location, environment.fasten_api_endpoint_base)}/secure/query`, query)
   }
 
-  getResourceGraph(graphType?: string): Observable<{[resourceType: string]: ResourceFhir[]}> {
+  getResourceGraph(graphType?: string, page?:number): Observable<ResourceGraphResponse> {
     if(!graphType){
       graphType = "MedicalHistory"
     }
+    let queryParams = {}
+    if(page){
+      //the backend is 0 indexed, but the frontend is 1 indexed
+      queryParams["page"] = page - 1
+    }
 
-    return this._httpClient.get<any>(`${GetEndpointAbsolutePath(globalThis.location, environment.fasten_api_endpoint_base)}/secure/resource/graph/${graphType}`)
+    return this._httpClient.get<any>(`${GetEndpointAbsolutePath(globalThis.location, environment.fasten_api_endpoint_base)}/secure/resource/graph/${graphType}`, {params: queryParams})
       .pipe(
         map((response: ResponseWrapper) => {
           console.log("RESPONSE", response)
-          return response.data as {[name: string]: ResourceFhir[]}
+          return response.data as ResourceGraphResponse
         })
       );
   }