followed this article in creating an angular app to azure website. (https://passos.com.au/build-and-deploy-an-angular-app-from-github-to-azure-website/) but in my case, we used Jenkins to deploy it on the website. i used Jenkins plugin (Publish an Azure Web App).
Here is the error i get.
2019-01-10T05:32:25.3182021Z,The node.js application will run with the default node.js version 8.9.4.,,0
2019-01-10T05:32:25.3338146Z,Selected npm version 5.6.0,,0
2019-01-10T05:33:27.4200572Z,npm WARN @angular/animations@7.2.0 requires a peer of @angular/core@7.2.0 but none is installed. You must install peer dependencies yourself.,,1
2019-01-10T05:33:27.4380331Z,up to date in 59.495s,,0
2019-01-10T05:33:27.4380331Z,npm WARN angular-6-datatable@0.8.0 requires a peer of @angular/core@^6.0.0 but none is installed. You must install peer dependencies yourself.,,1
2019-01-10T05:33:27.4513060Z,npm WARN angular-6-datatable@0.8.0 requires a peer of @angular/common@^6.0.0 but none is installed. You must install peer dependencies yourself.,,1
2019-01-10T05:33:27.4689400Z,npm WARN angular-6-datatable@0.8.0 requires a peer of @angular/platform-browser@^6.0.0 but none is installed. You must install peer dependencies yourself.,,1
2019-01-10T05:33:27.4988320Z,npm WARN The package @angular/cli is included as both a dev and production dependency.,,1
2019-01-10T05:33:27.5138032Z,npm WARN The package @angular/compiler-cli is included as both a dev and production dependency.,,1
2019-01-10T05:33:27.5138032Z,Building App in D:\home\site\repository…,,0
2019-01-10T05:33:27.5294295Z,npm WARN The package typescript is included as both a dev and production dependency.,,1
2019-01-10T05:33:27.5606827Z,npm WARN The package svg2sprite-cli is included as both a dev and production dependency.,,1
2019-01-10T05:33:27.5763069Z,npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.4 (node_modules\fsevents):,,1
2019-01-10T05:33:27.6075585Z,npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.4: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"ia32"}),,1
2019-01-10T05:33:27.6253798Z,,,1
2019-01-10T05:33:29.2496514Z,,,0
2019-01-10T05:33:29.2638549Z,> SB-Admin-BS4-Angular-7@7.0.0 build D:\home\site\repository,,0
2019-01-10T05:33:29.2638549Z,> ng build --prod --aot,,0
2019-01-10T05:33:29.2951058Z,,,0
2019-01-10T05:33:29.4044879Z,'ng' is not recognized as an internal or external command,,,1
2019-01-10T05:33:29.4201074Z,operable program or batch file.,,1
2019-01-10T05:33:29.4513736Z,npm ERR! code ELIFECYCLE,,1
2019-01-10T05:33:29.4669827Z,npm ERR! errno 1,,1
2019-01-10T05:33:29.4826098Z,Failed exitCode=1, command="D:\Program Files (x86)\nodejs\8.9.4\node.exe" "D:\Program Files (x86)\npm\5.6.0\node_modules\npm\bin\npm-cli.js" run build,,0
2019-01-10T05:33:29.4826098Z,npm ERR! SB-Admin-BS4-Angular-7@7.0.0 build: `ng build --prod --aot`,,1
2019-01-10T05:33:29.4982327Z,An error has occurred during web site deployment.,,0
2019-01-10T05:33:29.5151098Z,npm ERR! Exit status 1,,1
2019-01-10T05:33:29.5294872Z,npm ERR! ,,1
2019-01-10T05:33:29.5294872Z,npm ERR! Failed at the SB-Admin-BS4-Angular-7@7.0.0 build script.,,1
2019-01-10T05:33:29.5607390Z,npm ERR! This is probably not a problem with npm. There is likely additional logging output above.,,1
2019-01-10T05:33:29.5763692Z,,,1
2019-01-10T05:33:29.5763692Z,npm ERR! A complete log of this run can be found in:,,1
2019-01-10T05:33:29.5919898Z,npm ERR! D:\local\AppData\npm-cache\_logs\2019-01-10T05_33_29_436Z-debug.log,,1
2019-01-10T05:33:29.5919898Z,The system cannot find the drive specified.,,1
2019-01-10T05:33:29.6232380Z,Missing server.js/app.js files, web.config is not generated\r\nnpm WARN @angular/animations@7.2.0 requires a peer of @angular/core@7.2.0 but none is installed. You must install peer dependencies yourself.\r\nnpm WARN angular-6-datatable@0.8.0 requires a peer of @angular/core@^6.0.0 but none is installed. You must install peer dependencies yourself.\r\nnpm WARN angular-6-datatable@0.8.0 requires a peer of @angular/common@^6.0.0 but none is installed. You must install peer dependencies yourself.\r\nnpm WARN angular-6-datatable@0.8.0 requires a peer of @angular/platform-browser@^6.0.0 but none is installed. You must install peer dependencies yourself.\r\nnpm WARN The package @angular/cli is included as both a dev and production dependency.\r\nnpm WARN The package @angular/compiler-cli is included as both a dev and production dependency.\r\nnpm WARN The package typescript is included as both a dev and production dependency.\r\nnpm WARN The package svg2sprite-cli is included as both a dev and production dependency.\r\nnpm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.4 (node_modules\fsevents):\r\nnpm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.4: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"ia32"})\r\n\r\n'ng' is not recognized as an internal or external command,\r\noperable program or batch file.\r\nnpm ERR! code ELIFECYCLE\r\nnpm ERR! errno 1\r\nnpm ERR! SB-Admin-BS4-Angular-7@7.0.0 build: `ng build --prod --aot`\r\nnpm ERR! Exit status 1\r\nnpm ERR! \r\nnpm ERR! Failed at the SB-Admin-BS4-Angular-7@7.0.0 build script.\r\nnpm ERR! This is probably not a problem with npm. There is likely additional logging output above.\r\n\r\nnpm ERR! A complete log of this run can be found in:\r\nnpm ERR! D:\local\AppData\npm-cache\_logs\2019-01-10T05_33_29_436Z-debug.log\r\nThe system cannot find the drive specified.\r\nD:\Program Files (x86)\SiteExtensions\Kudu\79.11121.3655\bin\Scripts\starter.cmd deploy.cmd,,2