Introduction This is the third in the series discussing the functionality of the MCP server (@sassoftware/mcp-serverjs). In this article I discuss four new tools   program - Execute arbitrary SAS code directly - either inline code strings or stored .sas files in a SAS folder. User can supply input values which are passed to the program as macros. jobdef -  Execute a job definition with input values which are passed to the jobdef as macros job - Execute a job with input values which are passed to the job as macros sasQuery - Execute natural language queries against SAS table. Automatically translates business questions into SAS PROC SQL statements for quick data exploration. The tool executes a job and passes the generated sql and the user prompt it as macros.   SAS Studio Flows:  A SAS Studio flow can be published as a job. So the job tool can be used to run a SAS Studio flow. In a future article I will explore running simple and complex SAS Studio flows from the mcp server, But my reluctance to claim victory should not stop you from trying your flows thru the mcp server.   The latest version has been published to github    Scenarios for running SAS code In the following video I show running SAS code in SAS Studio. In the second video I show how to run these programs from the mcp server       Using MCP to run SAS code         What is next The next project is to enable the mcp server as a remote mcp server.   Links to previous articles 1.  A ModelContextProtocol Server(mcp) for Scoring with SAS Viya   2. A ModelContextProtocol Server(mcp) for Scoring with SAS Viya - Part 2: Persistence         ... View more

Introduction:   In the previous article I introduced a mcp server for scoring with SAS Viya. The next logical step is to persist scoring results  for post processing. The old me would have added added some code to the  scoring tool to persist the data. But with mcp servers I can pick and choose how and where I want to persist the data with little  or no coding. See this link for some mcp servers for data bases.   In this article, I am using the mcp/redis server to publish the scoring results to a SAS Viya CAS table. This allows me to post process the results immediately with SAS Viya. The picture below shows the flow. Given the architecture, I can replace the entire persistence flow with different set of mcp servers.   Why Redis? A few years ago, I worked on a POC which required streaming the scores (using SCR) via Redis. The solution consisted of a small set of custom docker containers in a pipeline.   Key points: .  The boxes in blue are the custom code I developed for this article The viyascoring mcp is the custom mcp server that was described in the previous article. mcp/redis is an open-source server from Redis. It requires a Redis server  The Redis server is the non-commercial version of Redis. This is ok for the demo, but you know the drill - for production systems get a commercial license. The subscriber is custom code  Subscribes to a specific channel( "score" in this demo) The received message is used to update a master table in SAS Viya The mcp server code is available on github at this link The redis subscriber code is available at this link     Solution in Action   Finally Hopefully I have convinced my fellow  SAS developers to enable their users to access the models using prompts.  If you do not know JavaScript or Python partner with an expert in those languages.      ... View more

  If you are a SAS programmer who wants to part of the agentic-ai world this article is for you.   MCP servers based on the Model Context Protocol (MCP) from Anthropic is one of the popular additions to the agentic-ai world. Users can mix and match capabilities supplied by multiple vendors from the comfort of a client like GitHub Copilot Experts can build MCP servers that is guaranteed to work on any MCP enabled client The brilliance of MCP is its simplicity.  Since its introduction in November 2024 its adoption has been nothing short of amazing. You can find many of them listed here.   So what does this mean for SAS developers and users? SAS developers create models using products like Model Studio and by writing custom SAS code that takes macro variables as input. Typically this is followed by developing some UI for the end users to access these models. The MCP server approach provides a nice alternative to deliver these models to the user.   Terminology: In the rest of this article, "model" refers to all of these: Models created with SAS solutions like Model Studio, Intelligent Decisioning etc... User written SAS programs Functions that call any SAS products using REST API  Details on the scoring MCP server   This article describes the viya-scoring-mcp-server  to score models described above. The source code is this  repository  It is provided under the Apache-2.0 license.   This diagram shows the flow from a user prompt to the final response.  MCP Server in Action   MCP server capabilities   The MCP server has the following tools for scoring.  Simple tool devascore - calculates a special score given two numbers. This is useful for verifying that the server is functioning. Also an easy to follow example of a tool Data related tools findLibrary - check if specified library exists listLibrary - list available libraries in cas or sas findTable - check if specified table exists in specified library in cas or sas listTables - list tables in a specified library in cas or sas readTable - read records from a cas or sas table Scoring with Models in MAS findModel - check if specified model exists in MAS server listModels - list models published to MAS modelInfo - display the input and output variables for a specified model modelScore - score using the selected model Scoring with SCR scrInfo - display the input and output variables for a specified SCR instance scrScore - score using the specified SCR instance Scoring with SAS code superstat - an example of accessing custom SAS code   Using the default MCP server Follow these basic steps   Step 1: Start the MCP server Issue this command from any shell on your desktop npx @sassoftware/mcp-serverjs@latest Make sure that you have a node version >=22 Step 2: Enable github copilot for the MCP server Similar methodologies can be used with other MCP enabled copilots. Go to the vscode settings and search for MCP. Then select Model Server Context Protocol. Edit its config json Add the following to the list of MCP servers { "viya-scoring-mcp-server": { "type": "http", "url": "http://localhost:8080/mcp" } } The name can be anything you like.   Sidebar: Authentication with your Viya Server This MCP server cli works similar to SAS supplied sas-viya cli commands. Use the following command to create the necessary token and refresh token. You need to do this once every 90 days or whenever the refresh token expires. Issue this command and follow instruction: sas-viya profile init Issue this command and follow the instructions: sas-viya auth loginCode Issuing prompts   Use the copilot prompt area to issue prompts. Here are some sample prompts list models sho Notes This demo server is "stateless" - it does not cache any values, including any Viya sessions the tools might have created. In a production system the designer has to make decisions on what needs to be cached and the implications of such caching. The implication of this design choice is felt most when the tool needs to create a compute session - the requests will take longer than when the compute session is cached. Useful links Documentation on modelcontextprotocol(mcp) mcp sdk ... View more

Introduction   Since you opened this article, you must take the next step and visit the SAS Innovate 2024 site to learn about SAS approach to providing a world class AI and Analytic experience for SAS users.     Like most application developers in the world, I was curious to learn about LLM and how one can put the LLM to work for specific domains.    My first attempt was to build a copilot for the drag and drop app builder (with react components) I was working on. While I did get an initial prototype working, I was left with the uneasy feeling that I was using a hammer when the job called for a screwdriver - I could build an entire app using drag and drop and minimal coding,  so why build a layer with LLM? I shelved the project with a note to build  @sassoftware/restaf library copilot  for building REST API based  Viya apps.   Around this time, OpenAI released the first version of their AI Assistant API for writing AI Assistants. The description from OpenAI is: Create an Assistant by defining its custom instructions and picking a model. If helpful, add files and enable tools like Code Interpreter, File Search, and Function calling. Create a Thread when a user starts a conversation. Add Messages to the Thread as the user asks questions. Run the Assistant on the Thread to generate a response by calling the model and the tools. There are a few more steps involved, but I was able to build assistants using this. The tools mentioned in step 1 allow developers to integrate their backend with the assistant. For Viya app developers this meant using the published REST API to access SAS Viya. In my case, I used the @sassoftware/restaf  libraries to make the calls to SAS Viya, but one could use any http library to make the calls.   Recently OpenAI released V2 beta that added support for vector store. The additional operations allow the developer to add to the vector store which could be used by the files_search tool. Please note that Azureai  Assistant does not support vector store at this time.   As with any project I work on, I always try to create reusable code (the lazy programmer approach!). This project is no different. I created a library @sassoftware/viya-assistantjs to simplify writing assistants. This library is available under Apache-2 license. Details on the Api and usage is here.    Use this library to build an Assistant in 5 steps Decide on the tools you need for your domain and develop them. The library comes with a default set of tools as an example and to jump start your journey. The source code for these tools are available in the repository. Additional examples are here. Call the setupAssistant  with configuration to initialize the assistant.  Pass in information to logon to Viya. The assistant will manage both CAS and SAS sessions.   See this link for details Pass in information for creating and managing the assistant. Accept prompt from user and call the runAssistant with the prompt. The OpenAI assistant maintains a thread of the conversation Process the response Repeat steps 3 and 4. The library has a uploadFile method for uploading documents to the vector store associated with the assistant. This method can also be used in the tools.   Key point of the samples tools The purpose of the sample tools is to show how easy it is to invoke SAS Viya from the tools and use the results in your response. While the mechanism to call Viya to resolve user prompts is necessary, it is not sufficient. One must have a well defined domain that is of interest to the user. The tools must be designed to access data and programs that are relevant to the domain. In SAS this usually is a collection of SAS programs  and data that can resolve  user questions about the domain.     Build an Assistant Step-by-Step    Import the necessary modules. Note the two entries imported from @sassoftware/viya-assistantjs   // Step 0: Import the necessary modules import * as readline from "node:readline/promises"; import fss from "fs/promises"; import { stdin as input, stdout as output } from "node:process"; import getToken from "./getToken.js"; import { setupAssistant, runAssistant } from "@sassoftware/viya-assistantjs"; let { host, token } = getToken();   Set up the tools.   const tools = [ { type: "function", function: { name: "listTables", description: `for a given library for either sas or cas source, get the list of available tables. (ex: list tables in cas library samples, list tables in sas library sashelp)`, parameters: { properties: { library: { type: "string", description: "A SAS library like casuser, sashelp, samples", }, start: { type: "integer", description: "Start at lookup at this index. Default is 0.", }, limit: { type: "integer", description: "Return only this many tables. If not specified, then return 10 tables.", }, source: { type: "string", description: "The source of the data. cas or sas", enum: ["cas", "sas"], }, }, type: "object", required: ["library"], }, }, }, ];   Set up the function for the tool.   async function listTables(params, userData, appControl) { let { library, source, start, limit } = params; // get session information let appEnv = await appControl.getViyaSession(source); // setup filters let p = { qs: { limit: limit == null ? 10 : limit, start: start == null ? 0 : start, }, }; // use restafedit library to get the list of tables. // Note you can make use your favorite library to make this call. see documentation let r = await appEnv.restafedit.getTableList(library, appEnv, p); // return the retrieved list return JSON.stringify(r); }   Write the chat program.    // run a chat session chat(config) .then((r) => console.log("done")) .catch((err) => console.log(err)); async function chat(config) { //Setup assistant let appControl = await setupAssistant(config); // create readline interface and chat with user const rl = readline.createInterface({ input, output }); // process user input in a loop while (true) { let prompt = await rl.question(">"); // exit session if (prompt.toLowerCase() === "exit" || prompt.toLowerCase() === "quit") { rl.close(); break; } // let assistant process the prompt let promptInstructions = " "; try { // run prompt let response = await runAssistant(appControl, prompt, promptInstructions); console.log(response[0].content); } catch (err) { console.log(err); } } }   Here is a short video showing the assistant in action.     Below is a recording of an assistant using the builtin tools.         Conclusion I hope you find this article useful. Feel free to clone the library and modify it to suit your needs. Since the library is based on an SDK that is in beta, I expect to enhance the library and publish updates as the OpenAI assistant evolves and I learn more.   All comments are welcomed.     ... View more

This article details a starter app, as described in the viyaapp GitHub repository, to setup your SAS Viya Web Application with minimal effort. Note: viyaapp is a branch of the restaf-uidemos repository. Upgrading from the sample application to your own application is as simple as replacing the index.html file and setting some configuration values. Additionally, creating a docker container for your application is a snap, as you'll see documented in this posting.   SAS Viya Server Setup You need to do this for all applications that will access SAS Viya. Typically these are set up by a SAS Viya Administrator. Create a clientid and clientsecret. This document uses these values: flow: authorization_code clientid: viyaapp clientsecret: secret redirect: <https://localhost:5002/viyaapp> Also set the following using SAS Environment configurations: sas.commons.web.security.cors: set AllowedUrl to https://localhost:5002 sas.commons.web.security.csrf: set to .* sas.commons.web.security.cookies: set sameSite to None   Technical Details The starter application uses @sassoftware/viya-appserverjs  as its app server. The primary purpose of the app server is to handle authentication and serve up the application to the browser.    As you will notice, the application has quite a few configurations. All these configurations are read by the application server to setup the application. Visit this  wiki pages for details.   Install Clone the repository and install the dependencies     git clone https://github.com/sassoftware/restaf-uidemos -b viyaapp viyaapp npm install cd viyaapp       Configuration Edit the .env file in the cloned repository and set the value of VIYA_SERVER to your SAS Viya server url.     VIYA_SERVER=https://Your-viya-server-url CLIENTID=clientapp CLIENTSECRET=secret APPNAME=viyaapp APPHOST=localhost APPPORT=5002 # If APPENTRY is not specified, it defaults to index.html APPENTRY=index.html       Run the application npm start Go to your browser and enter this to access the application https://localhost:5002/viyaapp You should get the SAS Logon dialog. Logon on with you SAS Viya userid and password. This will open the application.   Default Application The application is simple on functionality. It lists the available files on the SAS server. Press the button to display the file list.   The default application is in public/index.html. The full html is shown below with embedded notes.       <html> <head> <meta charset="UTF-8" > <! the script below returns useful information from server in a javascript object name LOGONPAYLOAD --> <!-- The most useful element is LOGONPAYLOAD.host , the url of the Viya server --> <!-- This helps avoid hard codung the Viya host url in the html --> <script src="/viyaapp/appenv" > </script> <-- http package to make calls to Viya --> <script src="https://cdnjs.cloudflare.com/ajax/libs/axios/0.26.1/axios.min.js">></script> <script> function setup() { console.log(LOGONPAYLOAD); /* for learning purposes */ } function runit() { document.getElementById('output').innerHTML = '...running'; let config = { url : `${LOGONPAYLOAD.host}/files/files`, method: 'GET', withCredentials: true /* This is required. This allows the browser communicate the credentials to the server */ } axios(config) .then (r => { console.log(r.data.items); let items = r.data.items.map( item => { return item.id;}) document.getElementById('output').innerHTML = JSON.stringify(items, null, 4); }) .catch(err => { document.getElementById('output').innerHTML = JSON.stringify(err, null, 4); }) } </script> <body onload="setup()"> <h1 id="head">Hi</h1> <h2> Custom call to Viya Server</h2> <div> <button onclick="runit()"> Press to make a call to file service </button> <br /> <br /> </div> <div> <pre id="output"></pre> </div> </body> </html>       Points of interest Replace index.html to point to your application's main entry point. If it is not index.html, then edit .env file and set the APPENTRY value to your entry point. Note that there is no code in the application for logging. This is handled for you by the app server included in this starter app. There are no references to authorization token. In your http call payload, set the withCredentials to true as shown in the example above. This lets the browser do the necessary bookkeeping to authorize the calls to SAS Viya. The /viyaapp/appenv end point is optional. It sets a JS variable LOGONPAYLOAD with the following structure. The host field is the most useful one. This is used in the application listed above.   "authType": "server", "redirect": null, /* advanced feature */ "host" : "your viya server url", "clientID": "your client id", "appName" : "The value of the APPNAME field in the .env file", "keepAlive": null, /* advanced feature to keep the session alive for longer periods */ "ns" : null /* for future use   Bonus Points Change the value of APPENTRY in the .env file to the value below. Restart the application and visit the same site for a more interesting starter app.         APPENTRY=indexrestaf       Running in Docker To run your application in docker, edit the docker-compose file. Set the value of VIYA_SERVER to the appropriate value.     version: "3.8" services: viyaapp: build: . restart: always ports: - 5002:8080 environment: - VIYA_SERVER=https://<your viya url> - CLIENTID=clientapp - CLIENTSECRET=secret - APPNAME=viyaapp       Note: The docker-compose command uses the Dockerfile in the same directory to create the container. The application is running on port 8080 in the container and the port is mapped to 5002 in the docker-compose file.   To run the application in docker run the following command.     docker compose up       and access the application as before.       https://localhost:5002/viyaapp       Conclusion  You just built a simple web application for SAS Viya with minimal effort. To make it your own, replace the contents of the public directory with your assets and modify the values in the configuration files.     ... View more

So you have a bunch of applications for SAS Viya that you want to migrate to the cloud and deploy them alongside SAS Viya - just like all the other cool kids. If you are just starting on this migration you will be confronted by this very long (and incomplete list) of things to learn – ingress, deployment, pods, loadBalancer, clusterIP, nodePort, secrets, secret Generator, configMap, configMap Generator, patches, operators, Kustomize, Helm charts and many more. DO NOT PANIC.  I have published a set of simple configuration files (https://lnkd.in/dEaAihv) that will get you up and running in no time. With a few key strokes you can deploy your application in the same cluster as SAS Viya. The figure below shows the resulting deployment.     Hope you find this useful. Cheers… Deva #kubernetes #sasprogramming #sassoftware #sasviya   ... View more

Preamble Hi fellow SAS Viya Programmers - Do you want to enable your users to access your SAS programs using REST API? Do you want to deliver your programs in a container? Then read on!   Introduction This article presents an easy way for SAS programmers to create a REST API server to front their SAS Viya Programs - including data steps, procedures, CAS Actions or CASL programs.   Full documentation for the create-viya-api tool is located on GitHub. Additionally, please follow this link if you'd like to see the details of the underlying server code. The entire project is based on restaf - An Easy Button To Access SAS Viya Using SAS Viya REST APIs.   Below is a short introductory video demonstrating the functionality.     Key Features   Define your API end points using JavaScript Authentication Accepts a valid SAS Viya token If called from an authenticated browser session it will get a token from SAS Viya By design it does not support client credentials(userid, password) - since bullets 1 and 2 are the more common use cases. In your handler (where you process the request), you have access to a context object with the following: The current valid token All the standard http artifacts - path, query, payload, headers etc Access the REST end points via swagger, web applications and any scripting environment Deploy the server in a Docker container The starter example has the following end points to jump start your development. These cover some basic scenarios. CAS actions CASL statements Compute service with the user-supplied code Specific program saved in the "server". In this example, the code is in a file on the API server, but in a real deployment this code will be in some repository   Next Steps Please try it out for yourself. And be sure to send your feedback - good or bad.    SAS Documentation Please refer to the SAS Support site for full documentation. ... View more

Hello Fellow SAS Viya Programmers: Earlier I had published a note on the viya-app-quickstart template for create-react-app. If you are anything like me you are probably waiting for the movie version - so here is a short video to get you going... Hope you give it a try... Cheers... Deva             ... View more

One of the common patterns in SAS Viya Web Applications is shown in the 3 images below.   The application starts with a landing page and a banner. The user selects an application to run from the hamburger menu in the banner. The user is routed to the selected menu     The viya-app-quickstart template for create-react-app is designed to simplify the development of such applications. Once the local development environment has been setup, you can add new applications as shown in the diagram below:     Please see viya-app-quickstart for instructions on how to build these applications using this template.   Cheers... Deva     ... View more

  The create-react-app tool is a very popular CLI to jump start the development of react-based applications. I created the create-react-restaf-viya-app as an extension of create-react-app. The main motivation for my new tool is to help restaf users build react-based Viya applications. restaf  is a  framework for building applications with SAS REST APIs, supported with SAS Viya and is composed of the following components:    restaf restaflib restaf-server Benefits The key benefits of using the create-react-restaf-viya-app CLI to jump start your SAS Viya Applications are:   You retain all the benefits of using create-react-app, which are well documented. You are automatically authenticated to the Viya Server. You can start making API calls right away during development just as you would in production. Note that this cli does not restrict you to using restaf - you are free to use your favorite library to access SAS Viya REST APIs.   A note on making API calls The recommended way to make the REST API calls is using restaf and restaflib. If for some reason (the author can think of few-to-none) you prefer to hand-code the REST API calls you can do that too. Remember that the session is authenticated using authorization_code flow and you'll need to code your calls accordingly.   Creating your React application Issue the command below to create the default application. npx create-react-restaf-viya-app react-appname --webapp webapp-name --title webapp-title --script scriptTags-file Example: npx create-react-restaf-viya-app mycoolapp   Only the react-appname is required. The optional parameters are: webapp – this is the user-friendly application name; defaults to viyademo title – the text for the title tag in index.html; defaults to SAS/Viya Application script – a file which has some HTML script tags to be inserted into index.html; default is a comment line file i    –   specify additional modules to install (ex: --i  "@material-ui/core prettyjson")   Using the generated application Once the app is created, you can start your development.   Key assumption The application authenticates using authorization_code flow.   Configuration Set the following in the .env file: CLIENTID – the default value is viyademo CLIENTSECRET – the default value is secret VIYA_SERVER – no defaults.You must specify this (e.g., http://myviya.com)   Some defaults The app server runs on localhost:5000/viyademo The clientid redirect is http://localhost:5000/viyademo The create-react-app server runs on its standard port(3000) For more detailed configuration options, see https://github.com/sassoftware/restaf-server/wiki   Application development Modify App.js to suit your needs. Install any additional packages your app might need.   Running in development mode Run this command to have HMR enabled. cd to-the-app-directory yarn dev   The flow of the application on the yarn dev command is show below. Step 1 : The user invokes the application at http://localhost:5000/viyademo. Step 2: The restaf-server authenticates with the Viya Server. The user is prompted for credentials. Step 3a: The status of the initialization is displayed in the browser. Step 3b: restaf-server runs the create-react-app’s npm start script, which launches your react application in a second tab of your browser. At this point you can view your application, edit your code and see the updated application. The session is authenticated -so you can make REST API calls to SAS Viya using restaf or any other library. Refer to the flow below for more details.   Running in Application mode Run the commands shown below. Note the create-react-app dev server will not start in this mode. cd to-the-app-directory yarn build yarn app   React Context - AppContext By default a react context named AppContext is created. To access the data code something like this: import React,{useContext} from 'react'; import {AppContext} from '../providers'; let appContext = useContext(AppContext); let {store, appOptions} = appContext; let {appenv, logonPayload} = appOptions;   The store is the restaf store object you use to make the API calls. The logonPayload has the following form: { authType: 'server' host : "your Viya hostname" }   The host value is useful if you are making use of Visual Analytics SDK and/or if you are coding the REST API calls without restaf.   Importing restaf and restaflib in your application These two libraries are part of the installed dependencies. To access them in your react components do these as follows: let restaf = require('@sassoftware/restaf/dist/restaf.js'); let restaflib = require('@sassoftware/restaflib/dist/restaflib.js'); or import * as restaf from '@sassoftware/restaf/dist/restaf.js'; import * as restaflib from '@sassoftware/restaf/dist/restaflib.js';   In all probability you will not refer directly to restaf in your code. Instead, use the store object in the AppContext (see above). This value is set as part of the application startup.   Finally The create-react-restaf-viya-app CLI tool helps jump start your application development. Feel free to clone the repository and make enhancements. ... View more

In many applications the users specifies the the input table. In CAS, the program can fail for one of the following reasons (among others) table exists but the table is not loaded table does not exist Caslib is incorrect A good program should check the input and give users a friendly message if there is a problem. The program should not make users crawl through logs to find out what happened. Below is a simple CASL function checkAndLoadTable that I use in my applications and libraries like @sassoftware/restaflib to make sure that the table is loaded and is ready to go. If necessary, the function will load the table.   The code is available in the attached file.   Typical usage   rc = checkAndLoadTable(caslib, name); if ( rc ne true) then do; ... handle error... end; else do; ... real work ... end;   Test program with sample output For your convenience here is a simple test program and sample results.   function test(testName, caslib, name) ; print '-----------------------------------------------------'; print testName; print '-----------------------------------------------------'; print 'Input caslib.name is: ' caslib '.' name; result = checkAndLoadTable(caslib, name); print 'Returned value: ' result; if (result eq true) then do; action table.recordCount r=result/ table = {caslib=caslib, name=name}; print 'Record Count: ' result.recordCount[1,1]; end; end;   Below is a sample run and output.   test('Loaded Table','systemData', 'postgres'); test('Table not pre-loaded','casuser', 'iris'); test('Bad caslib', 'x', 'iris'); test('Bad table', 'casuser', 'x'); and the sample output is ----------------------------------------------------- Loaded Table ----------------------------------------------------- Input caslib.name is: systemData.postgres Returned value: TRUE Record Count: 4015 ----------------------------------------------------- Table not pre-loaded ----------------------------------------------------- Input caslib.name is: casuser.iris Returned value: TRUE Record Count: 150 ----------------------------------------------------- Bad caslib ----------------------------------------------------- Input caslib.name is: x.iris Returned value: -1 ----------------------------------------------------- Bad table ----------------------------------------------------- Input caslib.name is: casuser.x Returned value: FALSE test('Promoted Table','systemData', 'postgres'); test('Table not loaded','casuser', 'iris'); test('Bad caslib', 'x', 'iris'); test('Bad table', 'casuser', 'x');   Finally This function can be used inside PROC CAS or in any CASL program running on the CAS server. If your application is used in spurts the checkAndLoadTable function is a good way to load the tables on demand. Remember that defensive programming saves hours of debugging for the user. Cheers. Deva ... View more

  Lazy Programmer’s Guide to Developing SAS Viya Applications   Philipp Lenssen writes in an article titled “Why Good Programmers Are Lazy and Dumb”   Lazy because only lazy programmers will want to write the kind of tools that might replace them in the end. Lazy, because only a lazy programmer will avoid writing monotonous, repetitive code – thus avoiding redundancy, the enemy of software maintenance and flexible refactoring. Mostly, the tools and processes that come out of this endeavor fired by laziness will speed up the production. This makes a lazy programmer a smart and efficient programmer.   From a SAS Viya Application developer’s perspective One of the great strengths of SAS Viya is the large collection of REST APIs that allow customers to integrate SAS Viya capabilities into their applications. Using these APIs, the user’s applications access the full complement of SAS Viya capabilities - data preparation, analysis and reporting.   Just about every SAS Viya application will call a few key services to do the heavy lifting on the Viya server. The figure below shows these typical patterns.   How many times does one have to write the same code to call different REST APIs when those are all similar, but for the payload? How many times does one to have to write code to “reduce” the JSON response to be useful in presentations?   You too can become a smart lazy programmer by using the techniques discussed in this article titled Lazy Programmer’s Guide to Developing SAS Viya Applications.   Avoid writing code that "writes itself", spend more time solving real business problems and use the extra time doing things you always wanted to do - like watching the world go by. ... View more

In my previous article I discussed a couple useful tools for deploying SAS Viya Applications. This article discusses the restaf-server app server,  designed for rapid development and deployment of SAS Viya applications.  Using a couple of configurations files, you can deploy an application with standard SAS Viya authentication and access to all SAS Viya services using REST APIs.   The key features of this app server are: authentication serve up static content extendable with custom routes TLS support restaf-server uses hapijs to do all the heavy lifting and takes advantage of its great configurability.   The complete restaf-server documentation and code are available in GitHub.   Basic Steps build your web application(s) obtain a ClientID and Clientsecret configure the server using a combination of env files Docker file environment variables create appenv.js for application specific configurations start the server with a simple command (see below for an example) npx @sassoftware/restaf-server --env=your-env-env-file --docker=your-Dockerfile --appenv=your-appenv.js-file   Typical flow Once the server is started the applications flows as shown below. The sequence of steps is numbered.       Quick start example Let us assume your application directory structure is along the lines of:   appdir/     public/       index.html     override.env     Dockerfile     appenv.js     package.json   Step 1: Create your application Create your web application using any framework. This article assumes that the artifacts of your application are in the public directory but that is purely a personal choice.   Step 2: Create clientid and clientsecret Obtain the clientid and clientsecret from your system administrator. If you are the administrator see Managing clientids page on GitHub for instructions on how to create this.   Step 3.1: Create the env file This file (along with Dockerfile) is used to configure the app server. Create a file with a  .env extension. In this example override.env is the name of this file. Below is an example of override.env.   VIYA_SERVER=http://your-viya-server # OAUTHFLOW - clientid - code|implicit AUTHFLOW=code # Get these from your administrator. Sample value shown below CLIENTID=appc CLIENTSECRET=secret # Where the app server is running: # Valid values: # localhost # http(s)://hostname # http(s)://ip address # When running in docker do not specify this. APPHOST=localhost # PORT for app server. Pick a port of your choice APPPORT=8080 # APPNAME – A user friendly name for your application # The appserver will start at {APPHOST}:{APPPORT}/{APPNAME} APPNAME=viyaapp # Location of assets # All assets are located relative to APPLOC APPLOC=./public # Main entry of your app # On successful authentication this entry will be displayed in the browser APPENTRY=index.html # The JS object is available as APPENV js variable in your app. # Include the following script tag in your html # <script src=”/{APPNAME}/appenv”></script> APPENV=appenv.js # TLS Support # see documentation on TLS Support    Step 3.2: Create the Dockerfile A typical Dockerfile for this example appears below.  This is the Dockerfile you will use if your application is delivered via docker containers.   FROM node:12.16.1-alpine LABEL maintainer="your-email" WORKDIR /usr/src/app COPY package*.json ./ RUN npm install COPY . . EXPOSE 8080 ENV APPHOST=0.0.0.0 ENV SAMESITE=None,false ENV KEEPALIVE=YES   Step 4: Create Application Specific configuration file In a typical SAS Viya Application, this file configures items like default caslibs, tables, reports, etc., for the application. See more details and an example in the viya-optimization-apps GitHub repository.   Build a placeholder appenv.js file with this content: let x= {hi: 'hi there'}; return x;   You then start the server with the following command: npx @sassoftware/restaf-server --env=./override.env --docker=./Dockerfile --appenv=./appenv.js   In the current example, the server will start at http://localhost:8080/viyaapp (http:{APPHOST}:{APPPORT}/APPNAME).   When you visit this link, SAS prompts you for user id and password. On successful authentication the html listed for APPENTRY (index.html in this example) displays in an authenticated browser session.   From your html you can make API calls to SAS Viya. Below is sample JavaScript code to get the root links for the files service using axios (note the host is the url for the Viya server).   async function makeViyaCall () { let config = { url : host + '/files/', method : 'GET', withCredentials: true, headers : { 'accept':'application/json,application/vnd.sas.api+json', } }; let r = await axios(config); return r.data; };   Finally With a few building materials and configuration values you can deploy your application easily and quickly. Feel free to clone and adopt this code as you see fit. Comments and contributions are welcome.   Cheers…   ... View more

Over the last several months I have been involved in the development of applications using SAS Viya. I witnessed a common pattern when integrating the capabilities of CAS and Visual Analytics Reports in web applications using SAS REST APIs.   To deploy the application at a user site the following is the typical list of artifacts. web applications SAS and CASL programs to execute the analysis application configuration One or more CAS tables which are updated at run time based on user actions; usually user input results in running multiple actions and updating of the tables. pre-defined reports used to visualize the results; the reports might be viewed using SAS Visual Analytics or embedded in the user’s web application using the VA SDK.   There are standard ways to deploy items 1 and 2.  This article is focused on two interactive CLI’s (available as npm packages) making the deployment of 3 through 5 simple and repeatable.  @sassoftware/registerclient – use this package to create, delete and list the clientids for three OAuth flows – password, implicit and authorization_code. @sassoftware/viyacaddy – a tool to assist with: import or export SAS Viya VA Reports import data stored as hdat, b7dat or csv import SAS and ds2 code for execution by datastep and scoring actions import astore and sasast files To facilitate the CI/CD process the tools allow for "batch" mode processing in addition to the CLI.   @sassoftware/registerclient The creation of the clientid is not magic and just requires a couple of API calls. There are several blogs and other documentation on developer.sas.com that discuss how to get these using curl, postman, etc. In particular, refer to Authentication to SAS Viya: a couple of approaches. I always felt that something so basic should be managed either with a UI or a CLI. This CLI attempts to achieve that goal.   The registerclient tool is part of the restaf GitHub repository and is accompanied by full documentation.   The sample code below launches the app, displays the help text, logs on to SAS, and registers a clientid myapp1. $ npx @sassoftware/registerclient --env register.env -------------------------------------- Welcome to @sassoftware/registerclient Enter help to get a list of all the commands Use logon command to start your SAS Viya session. User must be an admin. >> help Commands: help [command...] Provides help for a given command. exit Exits application. logon Logon to Viya list [all] List clients. Use all option to include system clientids config <config> File containing the configuration for clientid registeration new [options] <clientid> Add a new client with specified name delete <clientid> Delete specified client >> logon Enter your userid> sasdemo Enter your password> ******** Logon Successful >> add myapp1 -t authorization_code -s mysecret -r http://localhost:8080/myapp myapp1 has been added >> list >>>>>>>>>>>>>>User defined clientids clientid : myapp1 grantTypes: authorization_code,refresh_token redirect : http://localhost:8080/myapp undefined clientids detected >>exit   @sassoftware/viyacaddy This module is useful for the import and export of selected contents in SAS Viya. It is designed to address the simple import/export use case discussed earlier in this article. To move large amounts of data and reports please refer to the SAS Viya documentation.   The viyacaddy tool is located in the restaf GitHub repository and is accompanied by full documentation.   The sample code below launches the app, displays the help text, lists current reports, and imports a report.   $ npx @sassoftware/viyacaddy --env register.env Welcome to @sassoftware/viyacaddy Enter help to get a list of all the commands Use logon command to start your SAS Viya session >> help Commands: help [command...] Provides help for a given command. exit Exits application. logon Logon to Viya tables import [options] <dir> [files...] Import .sas, .ds2, .sashdat, .sasb7dat, .astore , .sasast, .csv into CAS Tables reports list List all the VA reports reports import [options] <dir> [files...] Import VA reports reports export [options] [files...] Export VA reports caslibs List all active caslibs tables list <caslib> List tables in a specified caslib >> logon Enter your userid> sasdemo Enter your password> ******** Logon Successful >> reports list [ 'Application Activity', 'CAS Activity', 'Disk Space', 'Home Loan Default Demo', 'SAS Viya Inventory' ] >> reports import C:\Users\sas\Documents\env testReport.json -f Public Imports started Import of C:\Users\sas\Documents\env/testReport.json as report testReport completed >> reports list [ 'Application Activity', 'CAS Activity', 'Disk Space', 'Home Loan Default Demo', 'SAS Viya Inventory' 'testReport' ] >>exit   Finally I hope you find these to be good additions to your toolbox. Please feel free to clone the code and make improvements.   Cheers…   ... View more