import axios, { AxiosInstance } from 'axios';
import { FhirResource, FhirBundle, FhirCapabilityStatement, FhirSearchParams } from '../types/fhir.js';
export class FhirProvider {
private client: AxiosInstance;
private baseUrl: string;
constructor(baseUrl: string, bearerToken?: string) {
this.baseUrl = baseUrl.replace(/\/$/, '');
this.client = axios.create({
baseURL: this.baseUrl,
headers: {
'Accept': 'application/fhir+json',
'Content-Type': 'application/fhir+json',
...(bearerToken && { 'Authorization': `Bearer ${bearerToken}` })
},
timeout: 30000
});
}
async getCapabilities(): Promise<FhirCapabilityStatement> {
const response = await this.client.get('/metadata');
return response.data;
}
async search(
resourceType: string,
params: FhirSearchParams = {},
elements?: string[],
count?: number,
sort?: string
): Promise<FhirBundle> {
const searchParams = new URLSearchParams();
// Add search parameters
Object.entries(params).forEach(([key, value]) => {
if (Array.isArray(value)) {
value.forEach(v => searchParams.append(key, v));
} else {
searchParams.append(key, value);
}
});
// Add _elements for field selection
if (elements && elements.length > 0) {
searchParams.append('_elements', elements.join(','));
}
// Add _count for pagination
if (count) {
searchParams.append('_count', count.toString());
}
// Add _sort for ordering
if (sort) {
searchParams.append('_sort', sort);
}
// Add _summary=data for token efficiency when elements not specified
if (!elements || elements.length === 0) {
searchParams.append('_summary', 'data');
}
const response = await this.client.get(`/${resourceType}?${searchParams.toString()}`);
return response.data;
}
async read(resourceType: string, id: string, elements?: string[]): Promise<FhirResource> {
let url = `/${resourceType}/${id}`;
if (elements && elements.length > 0) {
url += `?_elements=${elements.join(',')}`;
}
const response = await this.client.get(url);
return response.data;
}
async create(resourceType: string, resource: FhirResource): Promise<FhirResource> {
const response = await this.client.post(`/${resourceType}`, resource);
return response.data;
}
async update(resourceType: string, id: string, resource: FhirResource, versionId?: string): Promise<FhirResource> {
const headers: Record<string, string> = {};
if (versionId) {
headers['If-Match'] = `W/"${versionId}"`;
}
const response = await this.client.put(`/${resourceType}/${id}`, resource, { headers });
return response.data;
}
}
