rewrite: check classes and report classes

app/check/check.py

@@ -0,0 +1,16 @@
+from typing import Union, List
+
+from app.check.report import CheckReport
+
+
+class Check:
+    def execute(self):
+        raise NotImplemented
+
+    @property
+    def success(self) -> bool:
+        raise NotImplemented
+
+    @property
+    def report(self) -> Union[CheckReport, List[CheckReport]]:
+        raise NotImplemented

app/check/check_http.py

@@ -0,0 +1,85 @@
+from typing import List, Union
+from urllib.parse import urlparse, ParseResult
+
+import requests
+
+from app.check.check import Check
+from app.check.report import CheckReport
+
+
+class HTTPCheckInstance:
+    definition: str
+    method: str
+    url: ParseResult
+    status_code: int
+    report: CheckReport
+
+    def __init__(self, definition: str):
+        self.definition = definition
+        self.report = CheckReport()
+        self.report.summary = definition
+
+    def execute(self):
+        segments = self.definition.split('|')
+
+        self.status_code = 200
+        self.method = 'get'
+
+        self.url = urlparse(segments[0])
+
+        try:
+            status = segments[1]
+            self.status_code = int(status)
+        except IndexError:
+            pass
+        except ValueError:
+            self.report.success = False
+            self.report.errors.append(f'expected status code to be integer, got {segments[1]}')
+            return
+
+        try:
+            method = segments[2]
+            self.method = method.lower()
+        except IndexError:
+            pass
+
+        requester = getattr(requests, self.method, None)
+
+        if not requester:
+            self.report.success = False
+            self.report.errors.append(f'method "{self.method.upper()}" is not a valid HTTP method')
+            return
+
+        try:
+            r = requester(self.url.geturl())
+
+            if r.status_code != self.status_code:
+                self.report.success = False
+                self.report.errors.append(
+                    f"expected HTTP Status {self.status_code} but got {r.status_code}")
+
+        except ValueError:
+            self.report.success = False
+            self.report.errors.append(f'"{self.url.geturl()}" is not a valid URL')
+        except Exception as e:
+            self.report.success = False
+            self.report.errors.append(str(e))
+
+
+class HTTPCheck(Check):
+    checks: List[HTTPCheckInstance]
+
+    def __init__(self, definition: str):
+        self.checks = [HTTPCheckInstance(d) for d in definition.split(',')]
+
+    def execute(self):
+        for check in self.checks:
+            check.execute()
+
+    @property
+    def success(self) -> bool:
+        return all([c.report.success for c in self.checks])
+
+    @property
+    def report(self) -> Union[CheckReport, List[CheckReport]]:
+        return [c.report for c in self.checks]

app/check/report.py

@@ -0,0 +1,22 @@
+from typing import List
+
+import jinja2
+
+
+class CheckReport:
+    success: bool
+    summary: str
+    errors: List[str]
+
+    def __init__(self, success: bool = True, summary: str = '', errors: List[str] = None) -> None:
+        self.success = success
+        self.summary = summary
+        self.errors = errors if errors else []
+
+    def render(self) -> str:
+        env = jinja2.Environment(loader=jinja2.FileSystemLoader("app/views"),
+                                 keep_trailing_newline=True)
+
+        report_template = env.get_template('report.html')
+
+        return report_template.render({'report': self})

app/views.py

@@ -3,19 +3,18 @@
 import os
 from datetime import datetime
 from typing import Dict, Callable
-from urllib.parse import urlparse
 
 import boto3
 import redis
-import requests
 from django.conf import settings
 from django.db import connections
 from django.http import HttpResponse
 from opensearchpy import OpenSearch
 from tenacity import retry, stop_after_delay, RetryError, wait_fixed
 
 from celery_worker.tasks import demodjango_task
-from .util import render_connection_info, STATUS_SUCCESS, STATUS_FAIL
+from .check.check_http import HTTPCheck
+from .util import render_connection_info
 
 logger = logging.getLogger("django")
 
@@ -77,7 +76,9 @@ def index(request):
                 f"{settings.ACTIVE_CHECKS if settings.ACTIVE_CHECKS else 'all'}")
 
     return HttpResponse(
-        "<!doctype html><html><head><title>DemoDjango</title></head><body>"
+        "<!doctype html><html><head>"
+        "<title>DemoDjango</title>"
+        "</head><body>"
         f"{''.join(status_check_results)}"
         "</body></html>"
     )
@@ -203,48 +204,11 @@ def git_information():
 
 
 def http_check():
-    urls = os.environ.get("HTTP_CHECK_URLS", "https://httpstat.us/200|200|GET").split(",")
-    urls = [u for u in urls if u]
-
-    passed = True
-    message = ""
-
-    if not urls:
-        passed = False
-        message = ("No urls provided, set HTTP_CHECK_URLS to a comma separated list of "
-                   "URL|STATUS_CODE|METHOD Example: 'http://api.dev.demodjango.internal|200|GET,"
-                   "http://api.dev.demodjango.internal/path|403|POST'")
-
-    for url in urls:
-        segments = url.split("|")
-        url = segments[0]
-        url_parsed = urlparse(url)
-        status = int(segments[1]) if len(segments) > 1 else 200
-        method = segments[2].lower() if len(segments) > 2 else 'get'
-        request_success = True
-
-        check_message = f"{method.upper()} {url_parsed.hostname}{url_parsed.path} "
-
-        requester = getattr(requests, method, None)
-        if not requester:
-            check_message += f"invalid HTTP method {method} "
-            request_success = False
-
-        if request_success:
-            try:
-                r = requester(url)
-
-                if r.status_code != status:
-                    check_message += f"response has status code <code>{r.status_code}</code>, but expected <code>{status}</code> "
-                    passed = False
-                    request_success = False
-            except Exception as e:
-                passed = False
-                request_success = False
-                check_message += f"{e} "
-
-        check_message = f'<span style="color: green">{STATUS_SUCCESS}</span> {check_message}' if request_success else f'<span style="color: red">{STATUS_FAIL}</span> {check_message}'
-        check_message += "<br>"
-        message += check_message
-
-    return render_connection_info(ALL_CHECKS[HTTP_CONNECTION], passed, message)
+    urls = os.environ.get("HTTP_CHECK_URLS", "https://httpstat.us/200|200|GET")
+
+    check = HTTPCheck(urls)
+    check.execute()
+
+    return render_connection_info(ALL_CHECKS[HTTP_CONNECTION],
+                                  check.success,
+                                  "".join([c.render() for c in check.report]))

app/views/report.html

@@ -0,0 +1,4 @@
+<strong>{{ report.summary }}</strong>
+{% for error in report.errors %}
+    {{ error }}
+{% endfor %}