add pygeoapi plugin (#183)

* add pygeoapi plugin

* fix flake8

docs/content/pygeoapi-plugin.md

@@ -0,0 +1,43 @@
+# pygeoapi plugin
+
+## Overview
+
+pygeometa also provides a custom [pygeoapi](https://pygeoapi.io) processing plugin, providing
+metadata validation and generation via OGC API - Processes.
+
+## Installation
+
+To integrate this plugin in pygeoapi:
+
+- ensure pygeometa is installed into the pygeoapi deployment environment
+
+- add the two proceses to the pygeoapi configuration as follows:
+
+```yaml
+pygeometa-metadata-validate:
+    type: process
+    processor:
+        name: pygeometa.pygeoapi_plugin.PygeometaMetadataValidateProcessor
+
+pygeometa-metadata-generate:
+    type: process
+    processor:
+        name: pygeometa.pygeoapi_plugin.PygeometaMetadataGenerateProcessor
+```
+- regenerate the pygeoapi OpenAPI configuration
+
+```bash
+pygeoapi openapi generate $PYGEOAPI_CONFIG --output-file $PYGEOAPI_OPENAPI
+```
+
+- restart pygeoapi
+
+## Usage
+
+The resulting processes will be available at the following endpoints:
+
+* `/processes/pygeometa-metadata-validate`
+* `/processes/pygeometa-metadata-generate`
+
+Note that pygeoapi's OpenAPI/Swagger interface (at `/openapi`) also
+provides a developer-friendly interface to test and run requests

docs/mkdocs.yml

@@ -19,6 +19,7 @@ nav:
             - WMO Core Metadata Profile 2: reference/formats/wmo-wcmp2.md
             - WMO WIGOS Metadata Standard: reference/formats/wmo-wigos.md
 #        - Index: reference/index.md
+    - pygeoapi plugin: pygeoapi-plugin.md
 
 #theme: slate
 

pygeometa/pygeoapi_plugin.py

@@ -0,0 +1,286 @@
+# =================================================================
+#
+# Terms and Conditions of Use
+#
+# Unless otherwise noted, computer program source code of this
+# distribution # is covered under Crown Copyright, Government of
+# Canada, and is distributed under the MIT License.
+#
+# The Canada wordmark and related graphics associated with this
+# distribution are protected under trademark law and copyright law.
+# No permission is granted to use them outside the parameters of
+# the Government of Canada's corporate identity program. For
+# more information, see
+# http://www.tbs-sct.gc.ca/fip-pcim/index-eng.asp
+#
+# Copyright title to all 3rd party software distributed with this
+# software is held by the respective copyright holders as noted in
+# those files. Users are asked to read the 3rd Party Licenses
+# referenced with those assets.
+#
+# Copyright (c) 2022 Tom Kralidis
+#
+# Permission is hereby granted, free of charge, to any person
+# obtaining a copy of this software and associated documentation
+# files (the "Software"), to deal in the Software without
+# restriction, including without limitation the rights to use,
+# copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following
+# conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+#
+# =================================================================
+
+#
+# pygeometa as a service
+# ----------------------
+#
+# This file is intended to be used as a pygeoapi process plugin which will
+# provide pygeometa validation and metadata generation via OGC API - Processes.
+#
+# To integrate this plugin in pygeoapi:
+#
+# 1. ensure pygeometa is installed into the pygeoapi deployment environment
+#
+# 2. add the two proceses to the pygeoapi configuration as follows:
+#
+# pygeometa-metadata-validate:
+#     type: process
+#     processor:
+#         name: pygeometa.pygeoapi_plugin.PygeometaMetadataValidateProcessor
+#
+# pygeometa-metadata-generate:
+#     type: process
+#     processor:
+#         name: pygeometa.pygeoapi_plugin.PygeometaMetadataGenerateProcessor
+#
+# 3. (re)start pygeoapi
+#
+# The resulting processes will be available at the following endpoints:
+#
+# /processes/pygeometa-metadata-validate
+#
+# /processes/pygeometa-metadata-generate
+#
+# Note that pygeoapi's OpenAPI/Swagger interface (at /openapi) will also
+# provide a developer-friendly interface to test and run requests
+#
+
+import logging
+
+from pygeometa.core import read_mcf, validate_mcf
+from pygeometa.schemas import get_supported_schemas, load_schema
+
+from pygeoapi.process.base import BaseProcessor, ProcessorExecuteError
+
+
+LOGGER = logging.getLogger(__name__)
+
+INPUT_MCF = {
+    'title': 'Metadata control file (MCF)',
+    'description': 'a pygeometa metadata control file (MCF) as JSON',
+    'schema': {
+        'type': 'object',
+        'contentMediaType': 'application/json'
+    },
+    'minOccurs': 1,
+    'maxOccurs': 1,
+    'metadata': None,
+    'keywords': ['metadata control file', 'mcf']
+}
+
+PROCESS_METADATA_VALIDATE = {
+    'version': '0.1.0',
+    'id': 'pygeometa-metadata-validate',
+    'title': {
+        'en': 'pygeometa metadata control file (MCF) validation',
+    },
+    'description': {
+        'en': 'Validate metadata from a pygeometa metadata control file (MCF)',
+    },
+    'keywords': ['pygeometa', 'metadata', 'validate'],
+    'links': [{
+        'type': 'text/html',
+        'rel': 'about',
+        'title': 'information',
+        'href': 'https://geopython.github.io/pygeometa',
+        'hreflang': 'en-US'
+    }],
+    'inputs': {
+        'mcf': INPUT_MCF
+    },
+    'outputs': {
+        'validate-report': {
+            'title': 'Validate report',
+            'description': 'Validate report',
+            'schema': {
+                'type': 'object',
+                'contentMediaType': 'application/json'
+            }
+        }
+    },
+    'example': {
+        'inputs': {
+            'mcf': {'mcf': {'version': '1.0'}}
+        }
+    }
+}
+
+
+PROCESS_METADATA_GENERATE = {
+    'version': '0.1.0',
+    'id': 'pygeometa-metadata-generate',
+    'title': {
+        'en': 'pygeometa metadata generation',
+    },
+    'description': {
+        'en': 'Generate metadata from a pygeometa metadata control file (MCF)'
+    },
+    'keywords': ['pygeometa', 'metadata', 'generate'],
+    'links': [{
+        'type': 'text/html',
+        'rel': 'about',
+        'title': 'information',
+        'href': 'https://geopython.github.io/pygeometa',
+        'hreflang': 'en-US'
+    }],
+    'inputs': {
+        'mcf': INPUT_MCF,
+        'schema': {
+            'title': 'Metadata schema',
+            'description': 'Output metadata schema',
+            'schema': {
+                'type': 'string',
+                'enum': list(get_supported_schemas())
+            },
+            'minOccurs': 1,
+            'maxOccurs': 1,
+            'metadata': None,
+            'keywords': ['metadata', 'schema']
+        }
+    },
+    'outputs': {
+        'generation': {
+            'title': 'Generated metadata',
+            'description': 'Generated metadata',
+            'schema': {
+                'type': 'object',
+                'contentMediaType': 'application/json'
+            }
+        }
+    },
+    'example': {
+        'inputs': {
+            'mcf': {'mcf': {'version': '1.0'}},
+            'schema': 'oarec-record'
+        }
+    }
+}
+
+
+class PygeometaMetadataValidateProcessor(BaseProcessor):
+    """pygeometa metadata validate example"""
+
+    def __init__(self, processor_def):
+        """
+        Initialize object
+
+        :param processor_def: provider definition
+
+        :returns: pygeometa.pygeoapi_plugin.PygeometaMetadataValidateProcessor
+        """
+
+        super().__init__(processor_def, PROCESS_METADATA_VALIDATE)
+
+    def execute(self, data):
+
+        response = None
+        mimetype = 'application/json'
+        mcf = data.get('mcf')
+
+        if mcf is None:
+            msg = 'Missing input MCF'
+            LOGGER.error(msg)
+            raise ProcessorExecuteError(msg)
+
+        try:
+            LOGGER.debug('Validating MCF')
+            instance = read_mcf(mcf)
+            validate_mcf(instance)
+            response = 'Valid MCF'
+        except Exception as err:
+            response = f'Invalid MCF: {err}'
+
+        outputs = {
+            'id': 'validate-report',
+            'value': response
+        }
+
+        return mimetype, outputs
+
+    def __repr__(self):
+        return '<PygeometaMetadataValidateProcessor>'
+
+
+class PygeometaMetadataGenerateProcessor(BaseProcessor):
+    """pygeometa metadata generate example"""
+
+    def __init__(self, processor_def):
+        """
+        Initialize object
+
+        :param processor_def: provider definition
+
+        :returns: pygeometa.pygeoapi_plugin.PygeometaMetadataGenerateProcessor
+        """
+
+        super().__init__(processor_def, PROCESS_METADATA_GENERATE)
+
+    def execute(self, data):
+
+        response = None
+        mimetype = 'application/json'
+        mcf = data.get('mcf')
+        schema = data.get('schema')
+
+        if None in [mcf, schema]:
+            msg = 'Missing input MCF or schema'
+            LOGGER.error(msg)
+            raise ProcessorExecuteError(msg)
+
+        try:
+            LOGGER.debug('Generating metadata')
+            instance = read_mcf(mcf)
+            schema_object = load_schema(schema)
+
+            if schema_object.outputformat == 'json':
+                stringify = False
+            else:
+                stringify = True
+
+            response = schema_object.write(instance, stringify=stringify)
+
+        except Exception as err:
+            response = f'Generation error: {err}'
+
+        outputs = {
+            'id': 'generate-report',
+            'value': response
+        }
+
+        return mimetype, outputs
+
+    def __repr__(self):
+        return '<PygeometaMetadataGenerateProcessor>'