Python: Switch pyls on interpreter change

Change-Id: I458b635986a55003a1e7254e27e2df9667704273
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

1 files changed, 353 insertions, 0 deletions

diff --git a/src/plugins/python/pythonutils.cpp b/src/plugins/python/pythonutils.cpp
new file mode 100644
index 0000000000..29fc14953b
--- /dev/null
+++ b/src/plugins/python/pythonutils.cpp
@@ -0,0 +1,353 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "pythonutils.h"
+
+#include "pythonconstants.h"
+#include "pythonproject.h"
+#include "pythonrunconfiguration.h"
+#include "pythonsettings.h"
+
+#include <coreplugin/infobar.h>
+#include <coreplugin/progressmanager/progressmanager.h>
+
+#include <languageclient/languageclientsettings.h>
+#include <languageclient/languageclientmanager.h>
+
+#include <projectexplorer/session.h>
+#include <projectexplorer/target.h>
+
+#include <texteditor/textdocument.h>
+
+#include <utils/synchronousprocess.h>
+
+#include <QDir>
+#include <QFutureWatcher>
+#include <QRegularExpression>
+#include <QTimer>
+
+using namespace Utils;
+
+namespace Python {
+namespace Internal {
+
+static constexpr char startPylsInfoBarId[] = "Python::StartPyls";
+static constexpr char installPylsInfoBarId[] = "Python::InstallPyls";
+static constexpr char installPylsTaskId[] = "Python::InstallPylsTask";
+static constexpr char pythonUtilsTrContext[] = "Python::Utils";
+
+struct PythonLanguageServerState
+{
+    enum { CanNotBeInstalled, CanBeInstalled, AlreadyInstalled, AlreadyConfigured } state;
+    FilePath pylsModulePath;
+};
+
+static QString pythonName(const FilePath &pythonPath)
+{
+    static QHash<FilePath, QString> nameForPython;
+    if (!pythonPath.exists())
+        return {};
+    QString name = nameForPython.value(pythonPath);
+    if (name.isEmpty()) {
+        SynchronousProcess pythonProcess;
+        pythonProcess.setTimeoutS(2);
+        const CommandLine pythonVersionCommand(pythonPath, {"--version"});
+        const SynchronousProcessResponse response = pythonProcess.runBlocking(pythonVersionCommand);
+        if (response.result != SynchronousProcessResponse::Finished)
+            return {};
+        name = response.allOutput().trimmed();
+        nameForPython[pythonPath] = name;
+    }
+    return name;
+}
+
+FilePath getPylsModulePath(CommandLine pylsCommand)
+{
+    pylsCommand.addArg("-h");
+    SynchronousProcess pythonProcess;
+    pythonProcess.setEnvironment(pythonProcess.environment() + QStringList("PYTHONVERBOSE=x"));
+    SynchronousProcessResponse response = pythonProcess.runBlocking(pylsCommand);
+
+    static const QString pylsInitPattern = "(.*)"
+                                           + QRegularExpression::escape(
+                                               QDir::toNativeSeparators("/pyls/__init__.py"))
+                                           + '$';
+    static const QRegularExpression regexCached(" matches " + pylsInitPattern,
+                                                QRegularExpression::MultilineOption);
+    static const QRegularExpression regexNotCached(" code object from " + pylsInitPattern,
+                                                   QRegularExpression::MultilineOption);
+
+    const QString &output = response.allOutput();
+    for (auto regex : {regexCached, regexNotCached}) {
+        QRegularExpressionMatch result = regex.match(output);
+        if (result.hasMatch())
+            return FilePath::fromUserInput(result.captured(1));
+    }
+    return {};
+}
+
+QList<const LanguageClient::StdIOSettings *> configuredPythonLanguageServer()
+{
+    using namespace LanguageClient;
+    QList<const StdIOSettings *> result;
+    for (const BaseSettings *setting : LanguageClientManager::currentSettings()) {
+        if (setting->m_languageFilter.isSupported(FilePath::fromString("foo.py"),
+                                                  Constants::C_PY_MIMETYPE)) {
+            result << dynamic_cast<const StdIOSettings *>(setting);
+        }
+    }
+    return result;
+}
+
+static PythonLanguageServerState checkPythonLanguageServer(const FilePath &python)
+{
+    using namespace LanguageClient;
+    SynchronousProcess pythonProcess;
+    const CommandLine pythonLShelpCommand(python, {"-m", "pyls", "-h"});
+    SynchronousProcessResponse response = pythonProcess.runBlocking(pythonLShelpCommand);
+    if (response.allOutput().contains("Python Language Server")) {
+        const FilePath &modulePath = getPylsModulePath(pythonLShelpCommand);
+        for (const StdIOSettings *serverSetting : configuredPythonLanguageServer()) {
+            if (modulePath == getPylsModulePath(serverSetting->command()))
+                return {PythonLanguageServerState::AlreadyConfigured, FilePath()};
+        }
+
+        return {PythonLanguageServerState::AlreadyInstalled, getPylsModulePath(pythonLShelpCommand)};
+    }
+
+    const CommandLine pythonPipVersionCommand(python, {"-m", "pip", "-V"});
+    response = pythonProcess.runBlocking(pythonPipVersionCommand);
+    if (response.allOutput().startsWith("pip "))
+        return {PythonLanguageServerState::CanBeInstalled, FilePath()};
+    else
+        return {PythonLanguageServerState::CanNotBeInstalled, FilePath()};
+}
+
+FilePath detectPython(const FilePath &documentPath)
+{
+    FilePath python;
+
+    PythonProject *project = qobject_cast<PythonProject *>(
+        ProjectExplorer::SessionManager::projectForFile(documentPath));
+    if (!project)
+        project = qobject_cast<PythonProject *>(ProjectExplorer::SessionManager::startupProject());
+
+    if (project) {
+        if (auto target = project->activeTarget()) {
+            if (auto runConfig = qobject_cast<PythonRunConfiguration *>(
+                    target->activeRunConfiguration())) {
+                python = FilePath::fromString(runConfig->interpreter());
+            }
+        }
+    }
+
+    if (!python.exists())
+        python = PythonSettings::defaultInterpreter().command;
+
+    if (!python.exists() && !PythonSettings::interpreters().isEmpty())
+        python = PythonSettings::interpreters().first().command;
+
+    return python;
+}
+
+const LanguageClient::StdIOSettings *languageServerForPython(const FilePath &python)
+{
+    return findOrDefault(configuredPythonLanguageServer(),
+                         [pythonModulePath = getPylsModulePath(CommandLine(python, {"-m", "pyls"}))](
+                             const LanguageClient::StdIOSettings *setting) {
+                             return getPylsModulePath(setting->command()) == pythonModulePath;
+                         });
+}
+
+static LanguageClient::Client *registerLanguageServer(const FilePath &python)
+{
+    auto *settings = new LanguageClient::StdIOSettings();
+    settings->m_executable = python.toString();
+    settings->m_arguments = "-m pyls";
+    settings->m_name = QCoreApplication::translate(pythonUtilsTrContext,
+                                                   "Python Language Server (%1)")
+                           .arg(pythonName(python));
+    settings->m_languageFilter.mimeTypes = QStringList(Constants::C_PY_MIMETYPE);
+    LanguageClient::LanguageClientManager::registerClientSettings(settings);
+    return LanguageClient::LanguageClientManager::clientForSetting(settings).value(0);
+}
+
+class PythonLSInstallHelper : public QObject
+{
+    Q_OBJECT
+public:
+    PythonLSInstallHelper(const FilePath &python, QPointer<TextEditor::TextDocument> document)
+        : m_python(python)
+        , m_document(document)
+    {
+        m_watcher.setFuture(m_future.future());
+    }
+
+    void run()
+    {
+        Core::ProgressManager::addTask(m_future.future(), "Install PyLS", installPylsTaskId);
+        connect(&m_process,
+                QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
+                this,
+                &PythonLSInstallHelper::installFinished);
+        connect(&m_process,
+                &QProcess::readyReadStandardError,
+                this,
+                &PythonLSInstallHelper::errorAvailable);
+        connect(&m_process,
+                &QProcess::readyReadStandardOutput,
+                this,
+                &PythonLSInstallHelper::outputAvailable);
+
+        connect(&m_killTimer, &QTimer::timeout, this, &PythonLSInstallHelper::cancel);
+        connect(&m_watcher, &QFutureWatcher<void>::canceled, this, &PythonLSInstallHelper::cancel);
+
+        // on windows the pyls 0.28.3 crashes with pylint so just install the pyflakes linter
+        const QString &pylsVersion = HostOsInfo::isWindowsHost()
+                                         ? QString{"python-language-server[pyflakes]"}
+                                         : QString{"python-language-server[all]"};
+
+        m_process.start(m_python.toString(), {"-m", "pip", "install", pylsVersion});
+
+        Core::MessageManager::write(tr("Running '%1 %2' to install python language server")
+                                        .arg(m_process.program(), m_process.arguments().join(' ')));
+
+        m_killTimer.setSingleShot(true);
+        m_killTimer.start(5 /*minutes*/ * 60 * 1000);
+    }
+
+private:
+    void cancel()
+    {
+        SynchronousProcess::stopProcess(m_process);
+        Core::MessageManager::write(
+            tr("The Python language server installation canceled by %1.")
+                .arg(m_killTimer.isActive() ? tr("user") : tr("time out")));
+    }
+
+    void installFinished(int exitCode, QProcess::ExitStatus exitStatus)
+    {
+        m_future.reportFinished();
+        if (exitStatus == QProcess::NormalExit && exitCode == 0) {
+            if (LanguageClient::Client *client = registerLanguageServer(m_python))
+                LanguageClient::LanguageClientManager::reOpenDocumentWithClient(m_document, client);
+        } else {
+            Core::MessageManager::write(
+                tr("Installing the Python language server failed with exit code %1").arg(exitCode));
+        }
+        deleteLater();
+    }
+
+    void outputAvailable()
+    {
+        const QString &stdOut = QString::fromLocal8Bit(m_process.readAllStandardOutput().trimmed());
+        if (!stdOut.isEmpty())
+            Core::MessageManager::write(stdOut);
+    }
+
+    void errorAvailable()
+    {
+        const QString &stdErr = QString::fromLocal8Bit(m_process.readAllStandardError().trimmed());
+        if (!stdErr.isEmpty())
+            Core::MessageManager::write(stdErr);
+    }
+
+    QFutureInterface<void> m_future;
+    QFutureWatcher<void> m_watcher;
+    QProcess m_process;
+    QTimer m_killTimer;
+    const FilePath m_python;
+    QPointer<TextEditor::TextDocument> m_document;
+};
+
+static void installPythonLanguageServer(const FilePath &python,
+                                        QPointer<TextEditor::TextDocument> document)
+{
+    document->infoBar()->removeInfo(installPylsInfoBarId);
+
+    auto install = new PythonLSInstallHelper(python, document);
+    install->run();
+}
+
+static void setupPythonLanguageServer(const FilePath &python,
+                                      QPointer<TextEditor::TextDocument> document)
+{
+    document->infoBar()->removeInfo(startPylsInfoBarId);
+    if (LanguageClient::Client *client = registerLanguageServer(python))
+        LanguageClient::LanguageClientManager::reOpenDocumentWithClient(document, client);
+}
+
+void updateEditorInfoBar(const FilePath &python, TextEditor::TextDocument *document)
+{
+    const PythonLanguageServerState &lsState = checkPythonLanguageServer(python);
+
+    if (lsState.state == PythonLanguageServerState::CanNotBeInstalled
+        || lsState.state == PythonLanguageServerState::AlreadyConfigured) {
+        return;
+    }
+
+    Core::InfoBar *infoBar = document->infoBar();
+    infoBar->removeInfo(installPylsInfoBarId);
+    infoBar->removeInfo(startPylsInfoBarId);
+    if (lsState.state == PythonLanguageServerState::CanBeInstalled
+        && infoBar->canInfoBeAdded(installPylsInfoBarId)) {
+        auto message
+            =  QCoreApplication::translate(pythonUtilsTrContext,
+                  "Install and set up Python language server (PyLS) for %1 (%2). "
+                  "The language server provides Python specific completions and annotations.")
+                  .arg(pythonName(python), python.toUserOutput());
+        Core::InfoBarEntry info(installPylsInfoBarId,
+                                message,
+                                Core::InfoBarEntry::GlobalSuppression::Enabled);
+        info.setCustomButtonInfo(QCoreApplication::translate(pythonUtilsTrContext, "Install"),
+                                 [=]() { installPythonLanguageServer(python, document); });
+        infoBar->addInfo(info);
+    } else if (lsState.state == PythonLanguageServerState::AlreadyInstalled
+               && infoBar->canInfoBeAdded(startPylsInfoBarId)) {
+        auto message = QCoreApplication::translate(pythonUtilsTrContext,
+                                                   "Found a Python language server for %1 (%2). "
+                                                   "Should this one be set up for this document?")
+                           .arg(pythonName(python), python.toUserOutput());
+        Core::InfoBarEntry info(startPylsInfoBarId,
+                                message,
+                                Core::InfoBarEntry::GlobalSuppression::Enabled);
+        info.setCustomButtonInfo(QCoreApplication::translate(pythonUtilsTrContext, "Setup"),
+                                 [=]() { setupPythonLanguageServer(python, document); });
+        infoBar->addInfo(info);
+    }
+}
+
+void resetEditorInfoBar(TextEditor::TextDocument *document)
+{
+    Core::InfoBar *infoBar = document->infoBar();
+    infoBar->removeInfo(installPylsInfoBarId);
+    infoBar->removeInfo(startPylsInfoBarId);
+}
+
+} // namespace Internal
+} // namespace Python
+
+#include "pythonutils.moc"
+