sasjs/adapter
1
0
Fork 0
mirror of https://github.com/sasjs/adapter.git synced 2025-12-11 09:24:35 +00:00
Code Issues Projects Releases Wiki Activity

Merge pull request #275 from sasjs/allanbowe-patch-1

Browse Source 
Update README.md
This commit is contained in:
Allan Bowe
2021-03-22 22:37:16 +01:00
committed by GitHub
parent 2bdcbda54c c3e2b2ce70
commit 7efc0a1fb2
1 changed files with 159 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

161
README.md
View File

@@ -6,7 +6,7 @@ SASjs is a open-source framework for building Web Apps on SAS® platforms. You c
1 - `npm install @sasjs/adapter` - for use in a node project
2 - [Download](https://cdn.jsdelivr.net/npm/@sasjs/adapter@1/index.js) and use a copy of the latest JS file
2 - [Download](https://cdn.jsdelivr.net/npm/@sasjs/adapter@2/index.js) and use a copy of the latest JS file
3 - Reference directly from the CDN - in which case click [here](https://www.jsdelivr.com/package/npm/@sasjs/adapter?tab=collection) and select "SRI" to get the script tag with the integrity hash.
@@ -41,8 +41,165 @@ parmcards4;
You now have a simple web app with a backend service!
## Detailed Overview
The SASjs adapter is a JS library and a set of SAS Macros that handle the communication between the frontend app and backend SAS services.
There are three parts to consider:
1. JS request / response
2. SAS inputs / outputs
3. Configuration
### JS Request / Response
To install the library you can simply run `npm i @sasjs/adapter` or include a `<script>` tag with a reference to our [CDN](https://www.jsdelivr.com/package/npm/@sasjs/adapter).
Full technical documentation is available [here](https://adapter.sasjs.io). The main parts are:
### Instantiation
The following code will instantiate an instance of the adapter:
```javascript
let sasJs = new SASjs.default(
{
appLoc: "/Your/SAS/Folder",
serverType:"SAS9"
}
);
```
If you've installed it via NPM, you can import it as a default import like so:
```
import SASjs from '@sasjs/adapter';
```
You can then instantiate it with:
```
const sasJs = new SASjs({your config})
```
More on the config later.
### SAS Logon
The login process can be handled directly, as below, or as a callback function to a SAS request.
```javascript
sasJs.logIn('USERNAME','PASSWORD'
).then((response) => {
if (response.isLoggedIn === true) {
console.log('do stuff')
} else {
console.log('do other stuff')
}
}
```
### Request / Response
A simple request can be sent to SAS in the following fashion:
```javascript
sasJs.request("/path/to/my/service", dataObject)
.then((response) => {
// all tables are in the response object, eg:
console.log(response.tablewith2cols1row[0].COL1.value)
})
```
We supply the path to the SAS service, and a data object. The data object can be null (for services with no input), or can contain one or more tables in the following format:
```javascript
let dataObject={
"tablewith2cols1row": [{
"col1": "val1",
"col2": 42
}],
"tablewith1col2rows": [{
"col": "row1"
}, {
"col": "row2"
}]
};
```
There are optional parameters such as a config object and a callback login function.
The response object will contain returned tables and columns. Table names are always lowercase, and column names uppercase.
The adapter will also cache the logs (if debug enabled) and even the work tables. For performance, it is best to keep debug mode off.
## SAS Inputs / Outputs
The SAS side is handled by a number of macros in the [macro core](https://github.com/sasjs/core) library.
The following snippet shows the process of SAS tables arriving / leaving:
```sas
/* fetch all input tables sent from frontend - they arrive as work tables */
%webout(FETCH)
/* some sas code */
data some sas tables;
set from js;
run;
%webout(OPEN) /* open the JSON to be returned */
%webout(OBJ,some) /* `some` table is sent in object format */
%webout(ARR,sas) /* `sas` table is sent in array format, smaller filesize */
%webout(OBJ,tables,fmt=N) /* unformatted (raw) data */
%webout(OBJ,tables,label=newtable) /* rename tables on export */
%webout(CLOSE) /* close the JSON and send some extra useful variables too */
```
## Configuration
Configuration on the client side involves passing an object on startup, which can also be passed with each request. Technical documentation on the SASjsConfig class is available [here](https://adapter.sasjs.io/classes/types.sasjsconfig.html). The main config items are:
* `appLoc` - this is the folder under which the SAS services will be created.
* `serverType` - either `SAS9` or `SASVIYA`.
* `serverUrl` - the location (including http protocol and port) of the SAS Server. Can be omitted, eg if serving directly from the SAS Web Server, or in streaming mode.
* `debug` - if `true` then SAS Logs and extra debug information is returned.
* `useComputeApi` - if `true` and the serverType is `SASVIYA` then the REST APIs will be called directly (rather than using the JES web service).
* `contextName` - if missing or blank, and `useComputeApi` is `true` and `serverType` is `SASVIYA` then the JES API will be used.
The adapter supports a number of approaches for interfacing with Viya (`serverType` is `SASVIYA`). For maximum performance, be sure to [configure your compute context](https://sasjs.io/guide-viya/#shared-account-and-server-re-use) with `reuseServerProcesses` as `true` and a system account in `runServerAs`. This functionality is available since Viya 3.5. This configuration is supported when [creating contexts using the CLI](https://sasjs.io/sasjs-cli-context/#sasjs-context-create).
### Using JES Web App
In this setup, all requests are routed through the JES web app, at `YOURSERVER/SASJobExecution`. This is the most reliable method, and also the slowest. One request is made to the JES app, and remaining requests (getting job uri, session spawning, passing parameters, running the program, fetching the log) are made on the SAS server by the JES app.
```
{
appLoc:"/Your/Path",
serverType:"SASVIYA"
}
```
### Using the JES API
Here we are running Jobs using the Job Execution Service except this time we are making the requests directly using the REST API instead of through the JES Web App. This is helpful when we need to call web services outside of a browser (eg with the SASjs CLI or other commandline tools). To save one network request, the adapter prefetches the JOB URIs and passes them in the `__job` parameter.
```
{
appLoc:"/Your/Path",
serverType:"SASVIYA",
useComputeApi: true
}
```
### Using the Compute API
This approach is by far the fastest, as a result of the optimisations we have built into the adapter. With this configuration, in the first sasjs request, we take a URI map of the services in the target folder, and create a session manager - which spawns an extra session. The next time a request is made, the adapter will use the 'hot' session. Sessions are deleted after every use, which actually makes this _less_ resource intensive than a typical JES web app, in which all sessions are kept alive by default for 15 minutes.
```
{
appLoc:"/Your/Path",
serverType:"SASVIYA",
useComputeApi: true,
contextName: 'yourComputeContext'
}
```
# More resources
For more information and examples specific to this adapter you can check out the [user guide](https://sasjs.io/sasjs-adapter/) or the [technical](http://adapter.sasjs.io/) documentation.
For more information and examples specific to this adapter you can check out the [user guide](https://sasjs.io/sasjs-adapter/) or the [technical](http://adapter.sasjs.io/) documentation.
For more information on building web apps in general, check out these [resources](https://sasjs.io/training/resources/) or contact the [author](https://www.linkedin.com/in/allanbowe/) directly.
If you are a SAS 9 or SAS Viya customer you can also request a copy of [Data Controller](https://datacontroller.io) - free for up to 5 users, this tool makes use of all parts of the SASjs framework.