feat(exec): Add json output filter

src/inet_nm/_helpers.py

@@ -1,5 +1,6 @@
 """Interactive user prompts and general basic helpers."""
 
+import json
 import os
 import readline
 import sys
@@ -223,3 +224,55 @@ def nm_print(*args, **kwargs):
 def nm_input(*args, **kwargs):
     """Abstraction of input."""
     return input(*args, **kwargs)
+
+
+def nm_extract_valid_jsons(text):
+    """
+    Extract valid JSON strings from a given text.
+
+    This function iterates through the provided text character by character,
+    keeping track of the opening and closing braces to extract potential JSON strings.
+    It then validates each potential JSON string and returns a list of valid
+    JSON objects.
+
+    Args:
+    - text (str): The input text containing potential JSON strings.
+
+    Returns:
+    - list: A list of valid JSON objects.
+
+    Example:
+    >>> x = 'Log output 123\\n{ "a": 1} foobar\\nmore log stuff'
+    >>> x += '\\n{\\n  "b": 2, "c": 3,\\n"d": [{"e": 5}]\\n} and so on\\nblah blah'
+    >>> nm_extract_valid_jsons(x)
+    [{'a': 1}, {'b': 2, 'c': 3, 'd': [{'e': 5}]}]
+    """
+
+    def extract_potential_jsons(text):
+        potential_jsons = []
+        brace_count = 0
+        start_index = -1
+
+        for i, char in enumerate(text):
+            if char == "{":
+                if brace_count == 0:
+                    start_index = i
+                brace_count += 1
+            elif char == "}":
+                brace_count -= 1
+                if brace_count == 0 and start_index != -1:
+                    potential_jsons.append(text[start_index : i + 1])
+
+        return potential_jsons
+
+    potential_jsons = extract_potential_jsons(text)
+
+    valid_jsons = []
+    for potential in potential_jsons:
+        try:
+            valid_json = json.loads(potential)
+            valid_jsons.append(valid_json)
+        except json.JSONDecodeError:
+            pass
+
+    return valid_jsons

src/inet_nm/cli_exec.py

@@ -41,6 +41,12 @@ def main():
         default=None,
         help="Filter all lines with regex.",
     )
+    parser.add_argument(
+        "-j",
+        "--json-filter",
+        action="store_true",
+        help="Capture only json output.",
+    )
 
     cfg.config_arg(parser)
     chk.check_args(parser)
@@ -51,6 +57,7 @@ def main():
     seq = kwargs.pop("seq")
     force = kwargs.pop("force")
     output_filter = kwargs.pop("output_filter")
+    json_filter = kwargs.pop("json_filter")
     nodes = rh.sanity_check("/bin/bash", **kwargs)
 
     extra_env = rh.node_env_vars(args.config)
@@ -62,6 +69,7 @@ def main():
         ) as runner:
             runner.cmd = cmd
             runner.output_filter = output_filter
+            runner.json_filter = json_filter
             runner.run()
     except KeyboardInterrupt:
         print()

src/inet_nm/runner_apps.py

@@ -7,13 +7,14 @@
     NmTmuxWindowedRunner: Runs tmux with individual windows for each node.
 """
 
+import json
 import os
 import re
 import subprocess
 import time
 from typing import Dict
 
-from inet_nm._helpers import nm_print
+from inet_nm._helpers import nm_extract_valid_jsons, nm_print
 from inet_nm.data_types import NmNode
 from inet_nm.runner_base import NmNodesRunner
 
@@ -31,6 +32,7 @@ class NmShellRunner(NmNodesRunner):
     cmd = "echo $NM_IDX"
     SETUP_WAIT = 0.1
     output_filter = None
+    json_filter = False
     results = []
 
     @staticmethod
@@ -65,6 +67,27 @@ def get_output(process):
 
         return rc
 
+    @staticmethod
+    def _run_command_json(cmd, uid, board, idx, env):
+        # Run subprocess command to completion and capture output
+        result = subprocess.run(
+            cmd,
+            env=env,
+            shell=True,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+        )
+        data = nm_extract_valid_jsons(result.stdout.decode())
+        result_output = {
+            "uid": uid,
+            "board": board,
+            "idx": idx,
+            "data": data,
+            "stdout": result.stdout.decode(),
+            "result": result.returncode,
+        }
+        return result_output
+
     def func(self, node: NmNode, idx: int, env: Dict[str, str]):
         """Execute shell commands on nodes.
 
@@ -93,19 +116,28 @@ def func(self, node: NmNode, idx: int, env: Dict[str, str]):
             regex_str = None
         else:
             regex_str = re.compile(self.output_filter)
-        res = NmShellRunner._run_command(
-            cmd, prefix=prefix, env=full_env, regex_str=regex_str
-        )
-        if self.output_filter is None:
+        if self.json_filter:
+            res = NmShellRunner._run_command_json(
+                cmd, node.uid, node.board, idx, env=full_env
+            )
+            self.results.append(res)
+        else:
+            res = NmShellRunner._run_command(
+                cmd, prefix=prefix, env=full_env, regex_str=regex_str
+            )
+        if self.output_filter is None and not self.json_filter:
             self.results.append(f"RESULT:{prefix}{res}")
 
     def post(self):
         """Run after the operations on nodes have completed.
 
         It prints the results of the commands executed on nodes.
         """
-        for result in self.results:
-            nm_print(result)
+        if self.json_filter:
+            nm_print(json.dumps(self.results, indent=2, sort_keys=True))
+        else:
+            for result in self.results:
+                nm_print(result)
 
 
 class NmTmuxBaseRunner(NmNodesRunner):