Refactor all *.from_db() routines to use from_db_json()

This wrapper calls json.loads() but also handles None (returning None),
which enables the code at many call sites to be simplified.

Removed some callers' `if isinstance(field, str): ...` code, which has
the effect of newly disallowing field values that are already dicts.
However we've verified that all *.from_db() calls have raw database
outputs as their arguments, so such fields will be always be strings
and IMHO giving a dict to from_db_json() is really a logic error that
should be detected.

In SequencingGroupInternal.from_db() added `pop(..., None)` so that
a missing meta field is now accepted. The previous code suggests that
having pop() produce KeyError here was unintended.

The expected argument types for from_db_json() are listed in the
definition, but we don't list its return type. The best we could
say in general is `object` but most call sites expect `dict[str, str]`
(or occasionally `list[str]`) due to the shape of their expected JSON.
Specifying `object` would lead to mypy errors at these call sites.

db/python/layers/web.py

@@ -1,7 +1,6 @@
 # pylint: disable=too-many-locals, too-many-instance-attributes
 import asyncio
 import itertools
-import json
 import re
 from collections import defaultdict
 from datetime import date
@@ -15,7 +14,7 @@
 from db.python.tables.base import DbBase
 from db.python.tables.project import ProjectPermissionsTable
 from db.python.tables.sequencing_group import SequencingGroupTable
-from db.python.utils import escape_like_term
+from db.python.utils import escape_like_term, from_db_json
 from models.models import (
     AssayInternal,
     FamilySimpleInternal,
@@ -114,7 +113,7 @@ def _project_summary_process_assay_rows_by_sample_id(
             AssayInternal(
                 id=seq['id'],
                 type=seq['type'],
-                meta=json.loads(seq['meta']),
+                meta=from_db_json(seq['meta']),
                 sample_id=seq['sample_id'],
             )
             for seq in assay_rows
@@ -153,7 +152,7 @@ def _project_summary_process_sequencing_group_rows_by_sample_id(
             sg_id_to_sample_id[sg_id] = row['sample_id']
             sg_by_id[sg_id] = NestedSequencingGroupInternal(
                 id=sg_id,
-                meta=json.loads(row['meta']),
+                meta=from_db_json(row['meta']),
                 type=row['type'],
                 technology=row['technology'],
                 platform=row['platform'],
@@ -189,9 +188,9 @@ def _project_summary_process_sample_rows(
         smodels = [
             NestedSampleInternal(
                 id=s['id'],
-                external_ids=json.loads(s['external_ids']),
+                external_ids=from_db_json(s['external_ids']),
                 type=s['type'],
-                meta=json.loads(s['meta']) or {},
+                meta=from_db_json(s['meta']) or {},
                 created_date=str(sample_id_start_times.get(s['id'], '')),
                 sequencing_groups=sg_models_by_sample_id.get(s['id'], []),
                 non_sequencing_assays=filtered_assay_models_by_sid.get(s['id'], []),
@@ -450,8 +449,8 @@ async def get_project_summary(
                 pmodels.append(
                     NestedParticipantInternal(
                         id=p['id'],
-                        external_ids=json.loads(p['external_ids']),
-                        meta=json.loads(p['meta']),
+                        external_ids=from_db_json(p['external_ids']),
+                        meta=from_db_json(p['meta']),
                         families=pid_to_families.get(p['id'], []),
                         samples=list(smodels_by_pid.get(p['id'])),
                         reported_sex=p['reported_sex'],

db/python/tables/participant_phenotype.py

@@ -1,8 +1,8 @@
-import json
 from collections import defaultdict
 from typing import Any, Dict, List, Tuple
 
 from db.python.tables.base import DbBase
+from db.python.utils import from_db_json, to_db_json
 
 
 class ParticipantPhenotypeTable(DbBase):
@@ -32,7 +32,7 @@ async def add_key_value_rows(self, rows: List[Tuple[int, str, Any]]) -> None:
             {
                 'participant_id': r[0],
                 'description': r[1],
-                'value': json.dumps(r[2]),
+                'value': to_db_json(r[2]),
                 'audit_log_id': audit_log_id,
             }
             for r in rows
@@ -67,7 +67,7 @@ async def get_key_value_rows_for_participant_ids(
             pid = row['participant_id']
             key = row['description']
             value = row['value']
-            formed_key_value_pairs[pid][key] = json.loads(value)
+            formed_key_value_pairs[pid][key] = from_db_json(value)
 
         return formed_key_value_pairs
 
@@ -91,6 +91,6 @@ async def get_key_value_rows_for_all_participants(
             pid = row['participant_id']
             key = row['description']
             value = row['value']
-            formed_key_value_pairs[pid][key] = json.loads(value)
+            formed_key_value_pairs[pid][key] = from_db_json(value)
 
         return formed_key_value_pairs

db/python/utils.py

@@ -431,8 +431,10 @@ def get_logger():
     return _logger
 
 
-def from_db_json(text):
-    """Convert DB's JSON text to Python object"""
+def from_db_json(text: str | bytes | None):
+    """Convert database's JSON text to Python object"""
+    if text is None:
+        return None
     return json.loads(text)
 
 

models/models/analysis.py

@@ -1,10 +1,10 @@
 import enum
-import json
 from datetime import date, datetime
 from typing import Any
 
 from pydantic import BaseModel
 
+from db.python.utils import from_db_json
 from models.base import SMBase
 from models.enums import AnalysisStatus
 from models.utils.cohort_id_format import (
@@ -40,10 +40,6 @@ def from_db(**kwargs):
         analysis_type = kwargs.pop('type', None)
         status = kwargs.pop('status', None)
         timestamp_completed = kwargs.pop('timestamp_completed', None)
-        meta = kwargs.get('meta')
-
-        if meta and isinstance(meta, str):
-            meta = json.loads(meta)
 
         if timestamp_completed and isinstance(timestamp_completed, str):
             timestamp_completed = datetime.fromisoformat(timestamp_completed)
@@ -65,7 +61,7 @@ def from_db(**kwargs):
             output=kwargs.pop('output', []),
             timestamp_completed=timestamp_completed,
             project=kwargs.get('project'),
-            meta=meta,
+            meta=from_db_json(kwargs.get('meta')),
             active=bool(kwargs.get('active')),
             author=kwargs.get('author'),
         )

models/models/analysis_runner.py

@@ -1,6 +1,6 @@
 import datetime
-import json
 
+from db.python.utils import from_db_json
 from models.base import SMBase
 from models.models.project import ProjectId
 
@@ -34,10 +34,6 @@ class AnalysisRunnerInternal(SMBase):
     @staticmethod
     def from_db(**kwargs):
         """Convert from db Record"""
-        meta = kwargs.pop('meta')
-        if meta:
-            meta = json.loads(meta)
-
         _timestamp = kwargs.pop('timestamp')
         # if _timestamp:
         #     _timestamp = datetime.datetime.fromisoformat(_timestamp)
@@ -58,7 +54,7 @@ def from_db(**kwargs):
             hail_version=kwargs.pop('hail_version'),
             batch_url=kwargs.pop('batch_url'),
             submitting_user=kwargs.pop('submitting_user'),
-            meta=meta,
+            meta=from_db_json(kwargs.pop('meta')),
             audit_log_id=kwargs.pop('audit_log_id'),
             output_path=kwargs.pop('output_path'),
         )

models/models/assay.py

@@ -1,6 +1,6 @@
-import json
 from typing import Any
 
+from db.python.utils import from_db_json
 from models.base import OpenApiGenNoneType, SMBase
 from models.utils.sample_id_format import sample_id_format, sample_id_transform_to_raw
 
@@ -26,13 +26,7 @@ def __eq__(self, other):
     def from_db(d: dict):
         """Take DB mapping object, and return SampleSequencing"""
         meta = d.pop('meta', None)
-
-        if meta:
-            if isinstance(meta, bytes):
-                meta = meta.decode()
-            if isinstance(meta, str):
-                meta = json.loads(meta)
-        return AssayInternal(meta=meta, **d)
+        return AssayInternal(meta=from_db_json(meta), **d)
 
     def to_external(self):
         """Convert to transport model"""

models/models/audit_log.py

@@ -1,6 +1,6 @@
 import datetime
-import json
 
+from db.python.utils import from_db_json
 from models.base import SMBase
 from models.models.project import ProjectId
 
@@ -24,8 +24,5 @@ class AuditLogInternal(SMBase):
     @staticmethod
     def from_db(d: dict):
         """Take DB mapping object, and return SampleSequencing"""
-        meta = {}
-        if 'meta' in d:
-            meta = json.loads(d.pop('meta'))
-
-        return AuditLogInternal(meta=meta, **d)
+        meta = d.pop('meta', None)
+        return AuditLogInternal(meta=from_db_json(meta) or {}, **d)

models/models/cohort.py

@@ -1,5 +1,4 @@
-import json
-
+from db.python.utils import from_db_json
 from models.base import SMBase
 from models.models.project import ProjectId
 from models.utils.cohort_id_format import cohort_id_format
@@ -92,9 +91,7 @@ def from_db(d: dict):
         _id = d.pop('id', None)
         name = d.pop('name', None)
         description = d.pop('description', None)
-        criteria = d.pop('criteria', None)
-        if criteria and isinstance(criteria, str):
-            criteria = json.loads(criteria)
+        criteria = from_db_json(d.pop('criteria', None))
         project = d.pop('project', None)
 
         return CohortTemplateInternal(

models/models/participant.py

@@ -1,5 +1,4 @@
-import json
-
+from db.python.utils import from_db_json
 from models.base import OpenApiGenNoneType, SMBase
 from models.models.family import FamilySimple, FamilySimpleInternal
 from models.models.project import ProjectId
@@ -28,8 +27,8 @@ class ParticipantInternal(SMBase):
     def from_db(cls, data: dict):
         """Convert from db keys, mainly converting JSON-encoded fields"""
         for key in ['external_ids', 'meta']:
-            if key in data and isinstance(data[key], str):
-                data[key] = json.loads(data[key])
+            if key in data:
+                data[key] = from_db_json(data[key])
 
         return ParticipantInternal(**data)
 

models/models/project.py

@@ -1,6 +1,6 @@
-import json
 from typing import Optional
 
+from db.python.utils import from_db_json
 from models.base import SMBase
 
 ProjectId = int
@@ -20,5 +20,5 @@ class Project(SMBase):
     def from_db(kwargs):
         """From DB row, with db keys"""
         kwargs = dict(kwargs)
-        kwargs['meta'] = json.loads(kwargs['meta']) if kwargs.get('meta') else {}
+        kwargs['meta'] = from_db_json(kwargs.get('meta')) or {}
         return Project(**kwargs)

models/models/sample.py

@@ -1,5 +1,4 @@
-import json
-
+from db.python.utils import from_db_json
 from models.base import OpenApiGenNoneType, SMBase, parse_sql_bool
 from models.models.assay import Assay, AssayInternal, AssayUpsert, AssayUpsertInternal
 from models.models.sequencing_group import (
@@ -30,17 +29,11 @@ def from_db(d: dict):
         """
         _id = d.pop('id', None)
         type_ = d.pop('type', None)
-        meta = d.pop('meta', None)
+        meta = from_db_json(d.pop('meta', None))
         active = parse_sql_bool(d.pop('active', None))
 
-        if meta:
-            if isinstance(meta, bytes):
-                meta = meta.decode()
-            if isinstance(meta, str):
-                meta = json.loads(meta)
-
-        if 'external_ids' in d and isinstance(d['external_ids'], str):
-            d['external_ids'] = json.loads(d['external_ids'])
+        if 'external_ids' in d:
+            d['external_ids'] = from_db_json(d['external_ids'])
 
         return SampleInternal(id=_id, type=str(type_), meta=meta, active=active, **d)
 

models/models/sequencing_group.py

@@ -1,6 +1,6 @@
-import json
 from typing import Any
 
+from db.python.utils import from_db_json
 from models.base import OpenApiGenNoneType, SMBase
 from models.models.assay import Assay, AssayInternal, AssayUpsert, AssayUpsertInternal
 from models.utils.sample_id_format import sample_id_format, sample_id_transform_to_raw
@@ -47,9 +47,7 @@ class SequencingGroupInternal(SMBase):
     @classmethod
     def from_db(cls, **kwargs):
         """From database model"""
-        meta = kwargs.pop('meta')
-        if meta and isinstance(meta, str):
-            meta = json.loads(meta)
+        meta = from_db_json(kwargs.pop('meta', None))
 
         _archived = kwargs.pop('archived', None)
         if _archived is not None: