Merge pull request #98 from MJedr/prometheus-exporter

app: add prometheus exporter

Dockerfile

@@ -3,4 +3,5 @@ RUN apt update && apt install poppler-utils -y
 COPY setup.py setup.cfg README.rst ./
 COPY refextract refextract/
 RUN python setup.py install 
+ENV PROMETHEUS_MULTIPROC_DIR='/tmp'
 ENTRYPOINT exec gunicorn -b :5000 --access-logfile - --error-logfile - refextract.app:app --timeout 650

refextract/app.py

@@ -1,10 +1,14 @@
+import logging
+
 from flask import Flask, jsonify, make_response
+from prometheus_flask_exporter.multiprocess import \
+    GunicornInternalPrometheusMetrics
 from webargs import fields
 from webargs.flaskparser import FlaskParser
 
 from refextract.references.api import (extract_journal_reference,
-                                       extract_references_from_url,
-                                       extract_references_from_string)
+                                       extract_references_from_string,
+                                       extract_references_from_url)
 
 parser = FlaskParser()
 
@@ -36,7 +40,14 @@ def extract_journal_info(args):
                     extracted_publication_info = {}
                 extracted_publication_infos.append(extracted_publication_info)
         except Exception as e:
-            return make_response(jsonify({"message": f"Can not extract publication info data. Reason: {str(e)}"}), 500)
+            return make_response(
+                jsonify(
+                    {
+                        "message": f"Can not extract publication info data. Reason: {str(e)}"
+                    }
+                ),
+                500,
+            )
         return jsonify({"extracted_publication_infos": extracted_publication_infos})
 
     @app.route("/extract_references_from_text", methods=["POST"])
@@ -55,11 +66,12 @@ def extract_references_from_text(args):
             extracted_references = extract_references_from_string(
                 text,
                 override_kbs_files=journal_dict,
-                reference_format=u"{title},{volume},{page}",
+                reference_format="{title},{volume},{page}",
             )
         except Exception as e:
             return make_response(
-                jsonify({"message": f"Can not extract references. Reason: {str(e)}"}), 500
+                jsonify({"message": f"Can not extract references. Reason: {str(e)}"}),
+                500,
             )
         return jsonify({"extracted_references": extracted_references})
 
@@ -80,12 +92,13 @@ def extract_references_from_file_url(args):
                 url,
                 **{
                     "override_kbs_files": journal_dict,
-                    "reference_format": "{title},{volume},{page}"
-                }
+                    "reference_format": "{title},{volume},{page}",
+                },
             )
         except Exception as e:
             return make_response(
-                jsonify({"message": f"Can not extract references. Reason: {str(e)}"}), 500
+                jsonify({"message": f"Can not extract references. Reason: {str(e)}"}),
+                500,
             )
         return jsonify({"extracted_references": extracted_references})
 
@@ -94,5 +107,10 @@ def extract_references_from_file_url(args):
 
 app = create_app()
 
+if app.config.get('PROMETHEUS_ENABLE_EXPORTER_FLASK'):
+    logging.info("Starting prometheus metrics exporter")
+    metrics = GunicornInternalPrometheusMetrics.for_app_factory(prefix=app.name)
+    metrics.init_app(app)
+
 if __name__ == "__main__":
     app.run(host="0.0.0.0")

refextract/config.cfg

@@ -1,2 +1,3 @@
 FILES_DOWNLOAD_MAX_RETRIES = 3
 FILES_DOWNLOAD_TIMEOUT = 60
+PROMETHEUS_ENABLE_EXPORTER_FLASK = False

setup.py

@@ -39,7 +39,8 @@
     'inspire-utils~=3.0,>=3.0.25',
     'Flask>=2.0.3',
     "webargs<=5.4.0",
-    "gunicorn>=20.1.0"
+    "gunicorn>=20.1.0",
+    "prometheus-flask-exporter~=0.20,>=0.20.1"
 ]
 
 docs_require = [