Initial commit, using serverless framework

.dockerignore

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+.git
+.vscode/

.gitignore

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+# Distribution / packaging
+.Python
+env/
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+node_modules/
+parts/
+sdist/
+var/
+*.egg-info/
+.installed.cfg
+*.egg
+.vscode/
+
+# Serverless directories
+.serverless

Dockerfile

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+FROM python:3
+
+RUN pip3 --no-cache-dir install --upgrade \
+    pip \
+    pipenv
+
+COPY Pipfile .
+COPY Pipfile.lock .
+
+RUN pipenv install --system --deploy
+
+COPY handler.py .
+
+CMD ["python", "handler.py"]

Pipfile

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+[[source]]
+url = "https://pypi.org/simple"
+verify_ssl = true
+name = "pypi"
+
+[packages]
+"boto3" = "*"
+requests = "*"
+
+[dev-packages]
+pylint = "*"
+
+[requires]
+python_version = "3.7"

handler.py

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+from collections import defaultdict
+import boto3
+import datetime
+import os
+import requests
+import sys
+
+n_days = 7
+today = datetime.datetime.today()
+week_ago = today - datetime.timedelta(days=n_days)
+
+sparks = ['▁', '▂', '▃', '▄', '▅', '▆', '▇'] # Leaving out the full block because Slack doesn't like it: '█'
+
+def sparkline(datapoints):
+    lower = min(datapoints)
+    upper = max(datapoints)
+    width = upper - lower
+    n_sparks = len(sparks) - 1
+
+    line = ""
+    for dp in datapoints:
+        scaled = (dp - lower) / width
+        which_spark = int(scaled * n_sparks)
+        line += (sparks[which_spark])
+
+    return line
+
+def report_cost(event, context):
+    client = boto3.client('ce')
+
+    query = {
+        "TimePeriod": {
+            "Start": week_ago.strftime('%Y-%m-%d'),
+            "End": today.strftime('%Y-%m-%d'),
+        },
+        "Granularity": "DAILY",
+        "Filter": {
+            "Not": {
+                "Dimensions": {
+                    "Key": "RECORD_TYPE",
+                    "Values": [
+                        "Credit",
+                        "Refund",
+                        "Upfront",
+                        "Support",
+                    ]
+                }
+            }
+        },
+        "Metrics": ["UnblendedCost"],
+        "GroupBy": [
+            {
+                "Type": "DIMENSION",
+                "Key": "SERVICE",
+            },
+        ],
+    }
+
+    result = client.get_cost_and_usage(**query)
+
+    buffer = "%-40s %-7s $%5s\n" % ("Service", "Last 7d", "Yday")
+
+    cost_per_day_by_service = defaultdict(list)
+
+    # Build a map of service -> array of daily costs for the time frame
+    for day in result['ResultsByTime']:
+        for group in day['Groups']:
+            key = group['Keys'][0]
+            cost = float(group['Metrics']['UnblendedCost']['Amount'])
+
+            cost_per_day_by_service[key].append(cost)
+
+    # Sort the map by yesterday's cost
+    most_expensive_yesterday = sorted(cost_per_day_by_service.items(), key=lambda i: i[1][-1], reverse=True)
+
+    for service_name, costs in most_expensive_yesterday[:5]:
+        buffer += "%-40s %s $%5.2f\n" % (service_name, sparkline(costs), costs[-1])
+
+    other_costs = [0.0] * n_days
+    for service_name, costs in most_expensive_yesterday[5:]:
+        for i, cost in enumerate(costs):
+            other_costs[i] += cost
+
+    buffer += "%-40s %s $%5.2f\n" % ("Other", sparkline(other_costs), other_costs[-1])
+
+    total_costs = [0.0] * n_days
+    for day_number in range(n_days):
+        for service_name, costs in most_expensive_yesterday:
+            try:
+                total_costs[day_number] += costs[day_number]
+            except IndexError:
+                total_costs[day_number] += 0.0
+
+    buffer += "%-40s %s $%5.2f\n" % ("Total", sparkline(total_costs), total_costs[-1])
+
+    credits_expire_date = os.environ.get('CREDITS_EXPIRE_DATE')
+    if credits_expire_date:
+        credits_expire_date = datetime.datetime.strptime(credits_expire_date, "%m/%d/%Y")
+
+        credits_remaining_as_of = os.environ.get('CREDITS_REMAINING_AS_OF')
+        credits_remaining_as_of = datetime.datetime.strptime(credits_remaining_as_of, "%m/%d/%Y")
+
+        credits_remaining = float(os.environ.get('CREDITS_REMAINING'))
+
+        days_left_on_credits = (credits_expire_date - credits_remaining_as_of).days
+        allowed_credits_per_day = credits_remaining / days_left_on_credits
+
+        relative_to_budget = (total_costs[-1] / allowed_credits_per_day) * 100.0
+
+        if relative_to_budget < 60:
+            emoji = ":white_check_mark:"
+        elif relative_to_budget > 110:
+            emoji = ":rotating_light:"
+        else:
+            emoji = ":warning:"
+
+        summary = "%s Yesterday's cost of $%5.2f is %.0f%% of credit budget $%5.2f for the day." % (
+            emoji,
+            total_costs[-1],
+            relative_to_budget,
+            allowed_credits_per_day,
+        )
+    else:
+        summary = "Yesterday's cost was $%5.2f." % (total_costs[-1])
+
+    hook_url = os.environ.get('SLACK_WEBHOOK_URL')
+    if hook_url:
+        resp = requests.post(
+            hook_url,
+            json={
+                "text": summary + "\n\n```\n" + buffer + "\n```",
+            }
+        )
+
+        if resp.status_code != 200:
+            print("HTTP %s: %s" % (resp.status_code, resp.text))
+    else:
+        print(summary)
+        print(buffer)