Initial Commit

Global Variables/fhirInterface.js

@@ -0,0 +1,88 @@
+return {
+  getToken() {
+    return new Promise(async (resolve, reject) => {
+      try {
+        getRedisKey = function () {
+          return `fhir-${fhirSettings.jwt.clientId}`;
+        };
+
+        const tokenEntry = await redis.hGetAll(getRedisKey());
+        const currentTimeInSeconds = Math.floor(new Date().getTime() / 1000);
+
+        if (tokenEntry.exp >= currentTimeInSeconds) {
+          resolve(JSON.parse(tokenEntry.token));
+          return;
+        }
+
+        // start the expiry base before we create a new token
+        let expiryInSeconds = Math.floor(new Date().getTime() / 1000);
+
+        // Define headers
+        const headers = {
+          alg: "RS256",
+          typ: "JWT",
+        };
+
+        // Define your payload
+        const payload = {
+          iss: fhirSettings.jwt.client_id,
+          sub: fhirSettings.jwt.client_id,
+          aud: fhirSettings.token_url,
+        };
+
+        // Define token options (optional)
+        const options = {
+          expiresIn: "4m", // Token expires in 1 hour
+          notBefore: "0",
+          algorithm: "RS384",
+          keyid: "iva_id_1234",
+          jwtid: uuidv5("jwtid", fhirSettings.jwt.uuid_namespace),
+        };
+
+        let data = qs.stringify({
+          grant_type: "client_credentials",
+          client_assertion_type:
+            "urn:ietf:params:oauth:client-assertion-type:jwt-bearer",
+          client_assertion: jwt.sign(
+            payload,
+            fhirSettings.jwt.privateKey,
+            options
+          ),
+        });
+
+        let config = {
+          method: "post",
+          maxBodyLength: Infinity,
+          url: fhirSettings.token_url,
+          headers: {
+            "Content-Type": "application/x-www-form-urlencoded",
+          },
+          data: data,
+        };
+
+        const result = await axios(config);
+
+        if (result.status == 200) {
+          expiryInSeconds += result.data.expires_in;
+          console.log(
+            `fhirInterface.getToken: Adding ${getRedisKey()} to redis with expiry=${new Date(
+              expiryInSeconds * 1000
+            )}`
+          );
+          await redis.hSet(getRedisKey(), "exp", expiryInSeconds);
+          await redis.hSet(getRedisKey(), "token", JSON.stringify(result.data));
+          resolve(result.data);
+        } else {
+          reject(result.status);
+        }
+      } catch (err) {
+        console.log("fhirInterface.getToken: Error getting Token");
+        console.log(err);
+        if (err.response) {
+          console.log(err.response.data); // => the response payload
+        }
+        reject(err);
+      }
+    });
+  },
+};

Global Variables/fhirSettings.json

@@ -0,0 +1,10 @@
+{
+  "base_url": "https://fhir.epic.com/interconnect-fhir-oauth/api/FHIR",
+  "token_url": "https://fhir.epic.com/interconnect-fhir-oauth/oauth2/token",
+  "jwt": {
+    "uuid_namespace": "30e3078d-59fe-4151-8571-304c87580209",
+    "client_id": "66eaeb38-c5f7-41cb-8cd3-791efacf25e5",
+    "privateKey": "*****"
+  },
+  "patient_id": "T81lum-5p6QvDR7l6hv7lfE52bAbA2ylWBnv9CZEzNb0B"
+}

Proxy Scripts/fhirPatientRead.js

@@ -0,0 +1,23 @@
+(async () => {
+  try {
+    const token = await fhirInterface().getToken();
+
+    let config = {
+      method: "get",
+      url: `${fhirSettings.base_url}/DSTU2/Patient/${fhirSettings.patient_id}`,
+      headers: {
+        Accept: "application/json",
+        Authorization: `${token.token_type} ${token.access_token}`,
+      },
+    };
+
+    const result = await axios(config);
+    res.json(result.data);
+  } catch (err) {
+    if (err.response) {
+      res.status(err.response.status).json(err.response.data);
+    } else {
+      res.status(400).json(JSON.stringify(err));
+    }
+  }
+})();

README.md

@@ -1,3 +1,87 @@
 # fhir-iva-integration
 
-Example integration to https://fhir.epic.com/
+Example integration to https://fhir.epic.com/
+
+## Introduction
+
+This repository provides and example integration to EPIC using the [Epic on FHIR](https://fhir.epiv.com) Sandbox.  To use this example, you will need to create an account and Build an app run the APIs.
+
+## FHIR App
+
+This integration example requires you to build an App that allow the [SMART Backend Services (Backend OAUTH 2.0)](https://fhir.epic.com/Documentation?docId=oauth2&section=BackendOAuth2Guide) workflow to obtain an access token.
+
+To use this integration, you will need to create a public and private key as described in the section [Creating a Public Private Key Pair for JWT Signature](https://fhir.epic.com/Documentation?docId=oauth2&section=Creating-Key-Pair) and upload public key file to the FHIR Application and the Private Key to the *fhirSettings* global variable.
+
+When configuring the FHIR App, please make sure to:
+
+1. Select *Backend System* as the *Application Audience*
+2. Select the APIs you wish to use. NOTE: Only DSTU2 APIs have been tested
+3. Use the *Non-Production Client ID* in the *fhirSettings* Global Variable
+4. Upload your *publickey509.pem* file to *Sandbox JWT Signing Public Key
+5. Select *DSTU2* for *SMART on FHIR Version*.  Other versions have not been tested
+6. The rest should be optional for the Sandbox and not required for this example
+
+![FHIR App Example](/screenshots/Example%20FHIR%20App.png "FHIR App Example")
+
+## IVA Studio
+
+### Global Variables
+
+Add both *fhirInterface* as a Function and *fhirSettings* as an Object to Global Variables.
+
+*fhirInterface* currently as one function *getToken* that first checks REDIS for an unexpired token, then create one using the JWT method described by FHIR's documentation.
+
+> Because this is just an example, limited error handling and no Token refresh protocols have been implemented.
+
+#### fhirSettings
+
+Open the file fhirSettings and add your private key.  
+
+> NOTE: Remember, because this is a JSON Object, new lines from the private key will need to be replaced with '\n'.
+>
+> This is not recommended for a production environment.
+
+The file should look something like this when complete.
+
+```json
+{
+    "base_url" : "https://fhir.epic.com/interconnect-fhir-oauth/api/FHIR",
+    "token_url" : "https://fhir.epic.com/interconnect-fhir-oauth/oauth2/token",
+    "jwt" : {
+        "uuid_namespace" : "30e3078d-59fe-4151-8571-304c87580209",
+        "client_id" : "66eaeb38-c5f7-41cb-8cd3-791efacf25e5",
+        "privateKey" : "-----BEGIN RSA PRIVATE KEY-----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\nlOoomQDl08DhtkH/wSZrwJKgnNVCSPT+fLZzbTcmrsGkv6FdRthPjFY=\n-----END RSA PRIVATE KEY-----"
+        },
+    "patient_id" : "T81lum-5p6QvDR7l6hv7lfE52bAbA2ylWBnv9CZEzNb0B"
+}
+```
+
+### Proxy Scripts
+
+An example proxy script has been provided to test our a Patient.READ(DSTU2) API Call.  Ideally, you should work this into your Conversation Flows using the *Call API* Widget
+
+```javascript
+(async () => {
+    try {
+        const token = await fhirInterface().getToken();
+
+        let config = {
+          method: "get",
+          url: `${fhirSettings.base_url}/DSTU2/Patient/${fhirSettings.patient_id}`,
+          headers: {
+            "Accept" : "application/json",
+            "Authorization" : `${token.token_type} ${token.access_token}`
+          }
+        };
+
+        const result = await axios(config);
+        res.json(result.data);
+   } catch (err) {
+    if( err.response ){
+        res.status(err.response.status).json(err.response.data);
+    } else {
+        res.status(400).json(JSON.stringify(err));
+    }
+  }
+})();
+```