Run npm with QProcess under MacOs(osx)

Dannick Stark

I try to execute a npm command from my software. For that I call a Process. But I receive as error that /bin/sh: npm: command not found.

I am under MacOS (Catalina).

void AtTerminal::lunch()
{
    if(QSysInfo::productType() == "windows"){
        m_process->setProgram("cmd");
        m_process -> setArguments( QStringList() << "/C" << m_command );
    }else if (QSysInfo::productType() == "osx") {
        m_process->setProgram("sh");
        m_process -> setArguments( QStringList() << "-c" << m_command);
    }else {
        m_process->setProgram("sh");
        m_process -> setArguments( QStringList() << "-c" << m_command );
    }
    m_process->startDetached();
    m_process->close();
}

The process can't recognize the npm command although Nodejs is well installed.
Please, could someone help me.

jsulm

@Dannick-Stark What happens if you open a terminal and try to execute npm?
You probably need to use absolute path to npm executable.

ChrisW67

Probably the system path that your program has started with, and that sh inherits, does not contain the command npm.
You can check the default environment by looking at QProcessEnvironment::systemEnvironment().toStringList().
You can use the absolute path to npm or insert a suitable PATH through QProcess::setProcessEnvironment().

Dannick Stark

@jsulm I try it. With this, the Process is able to recognize npm but not the commands that npm will call.

I get as error: node command not found

jsulm

@Dannick-Stark What is content of m_command? And what is its type?

Dannick Stark

@ChrisW67 I looked at what was in QProcessEnvironment::systemEnvironment().toStringList(). And indeed npm was not there.
So I added it with:

AtTerminal::AtTerminal()
{
    QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
    env.insert("npm", "/usr/local/bin/npm");
    env.insert("pnpm", "/usr/local/bin/pnpm");
    m_process->setProcessEnvironment(env);
}

I add the PATH in the constructor of my class. But it had no effect.

@jsulm in m_command there ist: npm install i also try to use /usr/local/bin/npm install

jsulm

@Dannick-Stark said in Run npm with QProcess under MacOs(osx):

in m_command there ist: npm install i also try to use /usr/local/bin/npm install

As one string? QProcess parameters need to be a QStringList, all of them:

QStringList m_command << "npm" << "install";

That's why I asked what the type is.

Dannick Stark

@jsulm yes as one string.
I pass the command to A QStringList

m_process -> setArguments( QStringList() << "-c" << m_command);

It works well on Windows.

jsulm

@Dannick-Stark Please pass it as QStringList. It is also described in QProcess documentation.

Dannick Stark

In my code above, you can see that I pass the command to a QStringList.

void AtTerminal::lunch()
{
    if(QSysInfo::productType() == "windows"){
        m_process->setProgram("cmd");
        m_process -> setArguments( QStringList() << "/C" << m_command );
    }else if (QSysInfo::productType() == "osx") {
        m_process->setProgram("sh");
        m_process -> setArguments( QStringList() << "-c" << m_command);
    }else {
        m_process->setProgram("sh");
        m_process -> setArguments( QStringList() << "-c" << m_command );
    }
    m_process->startDetached();
    m_process->close();
}

jsulm

@Dannick-Stark Again: ALL parameters should be passed as QStringList.
You said that m_command is a QString containing "npm install", so it basically contains TWO parameters!
It should be like this:

m_process -> setArguments( QStringList() << "-c" << "npm" << "install");

Also, do you really need to start a shell? Can't you call npm directly without sh?

Dannick Stark

If it is possible to run npm directly without using sh that would be great.
But so far I haven't found a way to do it.

jsulm

@Dannick-Stark said in Run npm with QProcess under MacOs(osx):

But so far I haven't found a way to do it.

Simply use npm as command to execute:

m_process->setProgram("npm");
m_process -> setArguments( QStringList() << "install");

jsulm

@Dannick-Stark One correction to what I wrote before (thanks @JonB for the hint): if you use "sh -c" then on Linux you have to pass everything after -c as ONE string!