docker: context method

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

__tests__/docker.test.ts

@@ -57,6 +57,19 @@ describe('isAvailable', () => {
   });
 });
 
+describe('context', () => {
+  it('call docker context show', async () => {
+    const execSpy = jest.spyOn(Exec, 'getExecOutput');
+    await Docker.context().catch(() => {
+      // noop
+    });
+    expect(execSpy).toHaveBeenCalledWith(`docker`, ['context', 'show'], {
+      ignoreReturnCode: true,
+      silent: true
+    });
+  });
+});
+
 describe('printVersion', () => {
   it('call docker version', async () => {
     const execSpy = jest.spyOn(Exec, 'exec');

src/docker.ts

@@ -38,6 +38,18 @@ export class Docker {
       });
   }
 
+  public static async context(): Promise<string> {
+    return await Exec.getExecOutput(`docker`, ['context', 'show'], {
+      ignoreReturnCode: true,
+      silent: true
+    }).then(res => {
+      if (res.stderr.length > 0 && res.exitCode != 0) {
+        throw new Error(res.stderr);
+      }
+      return res.stdout.trim();
+    });
+  }
+
   public static async printVersion(): Promise<void> {
     await Exec.exec('docker', ['version']);
   }