Method launchRHelpServer

src/helpViewer/helpProvider.ts:42–107

()

    }

    public launchRHelpServer(): ChildProcessWithPort{
        const lim = '---vsc---';
        const portRegex = new RegExp(`.*${lim}(.*)${lim}.*`, 'ms');

        const newPackageRegex = new RegExp('NEW_PACKAGES');

        // starts the background help server and waits forever to keep the R process running
        const scriptPath = extensionContext.asAbsolutePath('R/help/helpServer.R');
        const args = [
            '--silent',
            '--no-echo',
            '--no-save',
            '--no-restore',
            '-e',
            'base::source(base::commandArgs(TRUE))',
            '--args',
            scriptPath
        ];
        const cpOptions = {
            cwd: this.cwd,
            env: {
                ...process.env,
                VSCR_LIB_PATHS: getRLibPaths(),
                VSCR_LIM: lim,
                VSCR_USE_RENV_LIB_PATH: config().get<boolean>('useRenvLibPath') ? 'TRUE' : 'FALSE'
            },
        };

        const childProcess: ChildProcessWithPort = spawn(this.rPath, args, cpOptions);

        let str = '';
        // promise containing the port number of the process (or 0)
        const portPromise = new Promise<number>((resolve) => {
            childProcess.stdout?.on('data', (data) => {
                try{
                    // eslint-disable-next-line
                    str += data.toString();
                } catch(e){
                    resolve(0);
                }
                if(portRegex.exec(str)){
                    resolve(Number(str.replace(portRegex, '$1')));
                    str = str.replace(portRegex, '');
                }
                if(newPackageRegex.exec(str)){
                    this.pkgListener?.();
                    str = str.replace(newPackageRegex, '');
                }
            });
            childProcess.on('close', () => {
                resolve(0);
            });
        });

        const exitHandler = () => {
            childProcess.port = 0;
        };
        childProcess.on('exit', exitHandler);