Merge ~pwlars/testflinger-cli:offer-cancel-job into testflinger-cli:master

[Paul Larson]

Small improvement from a suggested Lukas had today - when a user presses ctrl-C while polling the output, we can offer to either let them cancel the job or keep the job running in the background. I also added an option to let it just continue running the job and polling. Here's what a session looks like, showing all three selections:

13:55 $ testflinger reserve

Which queue do you want to use? ('?' to list) rpi3bp

Enter the name of the image you want to use or URL for a valid image starting with http(s)://... ('?' to list) core20-armhf-beta

Enter the ssh key(s) you wish to use: (ex: lp:userid, gh:userid) lp:pwlars

The following yaml will be submitted:
job_queue: rpi3bp
provision_data:
    url: http://cdimage.ubuntu.com/ubuntu-core/20/dangerous-beta/pending/ubuntu-core-20-armhf+raspi.img.xz
reserve_data:
    ssh_keys:
    - lp:pwlars
Proceed? (Y/n)
Job submitted successfully!
job_id: 17e8e062-6aa8-40f5-b23d-a02830f7b08d
This job is waiting on a node to become available.
Jobs ahead in queue: 0
**************************************************

* Starting testflinger setup phase on rpi3bp-004 *

**************************************************

Cleaning up container if it exists...
Error: No such container: rpi3bp004

******************************************************

* Starting testflinger provision phase on rpi3bp-004 *

******************************************************
^C
Cancel job 17e8e062-6aa8-40f5-b23d-a02830f7b08d before exiting (y)es/(N)o/(c)ontinue? c
2020-11-20 19:56:37,003 rpi3bp_004 INFO: DEVICE AGENT: BEGIN provision
2020-11-20 19:56:37,003 rpi3bp_004 INFO: DEVICE AGENT: Booting Master Image
2020-11-20 19:56:37,003 rpi3bp_004 INFO: DEVICE AGENT: Making sure the master image is booted
2020-11-20 19:56:37,003 rpi3bp_004 INFO: DEVICE AGENT: Checking if test image booted.
2020-11-20 19:56:37,174 rpi3bp_004 INFO: DEVICE AGENT: Checking if master image booted.
2020-11-20 19:56:37,503 rpi3bp_004 INFO: DEVICE AGENT: Downloading file from http://cdimage.ubuntu.com/ubuntu-core/20/dangerous-beta/pending/ubuntu-core-20-armhf+raspi.img.xz
^C
Cancel job 17e8e062-6aa8-40f5-b23d-a02830f7b08d before exiting (y)es/(N)o/(c)ontinue?

13:57 $ testflinger poll 17e8e062-6aa8-40f5-b23d-a02830f7b08d
2020-11-20 19:57:08,742 rpi3bp_004 INFO: DEVICE AGENT: Flashing Test Image

2020-11-20 19:57:09,195 rpi3bp_004 INFO: DEVICE AGENT: Running: nc.traditional 10.101.49.222 35473| xzcat| sudo dd of=/dev/mmcblk0 bs=16M
^C
Cancel job 17e8e062-6aa8-40f5-b23d-a02830f7b08d before exiting (y)es/(N)o/(c)ontinue? y

13:57 $ testflinger status 17e8e062-6aa8-40f5-b23d-a02830f7b08d
cancelled

[Paul Larson (pwlars)]

(ignore the bad line break in the middle of the options, it doesn't look that way - just lp reformatting it for me)

[Sheila Miguez (codersquid)]

lgtm. Maybe ask Lukas if he likes the interface.

review: Approve

[Lukas Waymann (meribold)]

Looks good to me!

review: Approve

diff --git a/testflinger_cli/__init__.py b/testflinger_cli/__init__.py
index 0bd12e7..862f51d 100644
--- a/testflinger_cli/__init__.py
+++ b/testflinger_cli/__init__.py
@@ -178,8 +178,11 @@ class TestflingerCli:
         if job_state in ('complete', 'cancelled'):
             raise SystemExit('Job {} is already in {} state and cannot be '
                              'cancelled.'.format(self.args.job_id, job_state))
-        self.client.post_job_state(self.args.job_id, 'cancelled')
-        self.history.update(self.args.job_id, 'cancelled')
+        self.do_cancel(self.args.job_id)
+
+    def do_cancel(self, job_id):
+        self.client.post_job_state(job_id, 'cancelled')
+        self.history.update(job_id, 'cancelled')
 
     def configure(self):
         if self.args.setting:
@@ -323,25 +326,38 @@ class TestflingerCli:
         while job_state != 'complete':
             if job_state == 'cancelled':
                 break
-            if job_state == 'waiting':
+            try:
+                if job_state == 'waiting':
+                    try:
+                        queue_pos = self.client.get_job_position(job_id)
+                        if int(queue_pos) != prev_queue_pos:
+                            prev_queue_pos = int(queue_pos)
+                            print('Jobs ahead in queue: {}'.format(queue_pos))
+                    except Exception:
+                        # Ignore any bad response, this will retry
+                        pass
+                time.sleep(10)
+                output = ''
                 try:
-                    queue_pos = self.client.get_job_position(job_id)
-                    if int(queue_pos) != prev_queue_pos:
-                        prev_queue_pos = int(queue_pos)
-                        print('Jobs ahead in queue: {}'.format(queue_pos))
+                    output = self.get_latest_output(job_id)
                 except Exception:
-                    # Ignore any bad response, this will retry
-                    pass
-            time.sleep(10)
-            output = ''
-            try:
-                output = self.get_latest_output(job_id)
-            except Exception:
-                continue
-            if output:
-                print(output, end='', flush=True)
-            job_state = self.get_job_state(job_id)
-            self.history.update(job_id, job_state)
+                    continue
+                if output:
+                    print(output, end='', flush=True)
+                job_state = self.get_job_state(job_id)
+                self.history.update(job_id, job_state)
+            except KeyboardInterrupt:
+                choice = input('\nCancel job {} before exiting '
+                               '(y)es/(N)o/(c)ontinue? '.format(job_id))
+                if choice:
+                    choice = choice[0].lower()
+                    if choice == 'c':
+                        continue
+                    if choice == 'y':
+                        self.do_cancel(job_id)
+                # Both y and n will allow the external handler deal with it
+                raise
+
         print(job_state)
 
     def jobs(self):
@@ -461,6 +477,8 @@ class TestflingerCli:
         image = ""
         flex_url = ""
         if images and images[list(images.keys())[0]].startswith('url:'):
+            # If this device can take URLs, offer to let the user enter one
+            # instead of just using the known images
             flex_url = "or URL for a valid image starting with http(s)://... "
         while not image or image == "?":
             image = input("\nEnter the name of the image you want to use " +