From a73c710e94015db92e0295a9de46366b08044173 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Henrik=20tom=20W=C3=B6rden?= <henrik@trineo.org> Date: Thu, 7 Apr 2022 15:36:13 +0200 Subject: [PATCH] MAINT: move doc file to f-refactor-high-level-api --- src/doc/high_level_api.org | 121 ------------------------------------- 1 file changed, 121 deletions(-) delete mode 100644 src/doc/high_level_api.org diff --git a/src/doc/high_level_api.org b/src/doc/high_level_api.org deleted file mode 100644 index c24bc7ba..00000000 --- a/src/doc/high_level_api.org +++ /dev/null @@ -1,121 +0,0 @@ -* High Level API - -In addition to the old standard pylib API, new versions of pylib ship with a high level API -that facilitates usage of CaosDB entities within data analysis scripts. In a nutshell that -API exposes all properties of CaosDB Records as standard python attributes making their -access easier. - -Or to spell it out directly in Python: -#+BEGIN_SRC python - - import caosdb as db - # Old API: - r = db.Record() - r.add_parent("Experiment") - r.add_property(name="alpha", value=5) - r.get_property("alpha").value = 25 # setting properties (old api) - print(r.get_property("alpha").value + 25) # getting properties (old api) - - from caosdb.high_level_api import convert_to_python_entity - obj = convert_to_python_object(r) # create a high level entity - obj.r = 25 # setting properties (new api) - print(obj.r + 25) # getting properties (new api) - -#+END_SRC - - -** Quickstart - -The module, needed for the high level API is called: -~caosdb.high_level_api~ - -There are two functions converting entities between the two representation (old API and new API): -- ~convert_to_python_object~: Convert entities from **old** into **new** representation. -- ~convert_to_entity~: Convert entities from **new** into **old** representation. - -Furthermore there are a few utility functions which expose very practical shorthands: -- ~new_high_level_entity~: Retrieve a record type and create a new high level entity which contains properties of a certain importance level preset. -- ~create_record~: Create a new high level entity using the name of a record type and a list of key value pairs as properties. -- ~load_external_record~: Retrieve a record with a specific name and return it as high level entity. -- ~create_entity_container~: Convert a high level entity into a standard entity including all sub entities. -- ~query~: Do a CaosDB query and return the result as a container of high level objects. - -So as a first example, you could retrieve any record from CaosDB and use it using its high level representation: -#+BEGIN_SRC python - from caosdb.high_level_api import query - - res = query("FIND Record Experiment") - experiment = res[0] - # Use a property: - print(experiment.date) - - # Use sub properties: - print(experiment.output[0].path) -#+END_SRC - -The latter example demonstrates, that the function query is very powerful. For its default parameter -values it automatically resolves and retrieves references recursively, so that sub properties, -like the list of output files "output", become immediately available. - -**Note** that for the old API you were supposed to run the following series of commands -to achieve the same result: -#+BEGIN_SRC python - import caosdb as db - - res = db.execute_query("FIND Record Experiment") - output = res.get_property("output") - output_file = db.File(id=output.value[0].id).retrieve() - print(output_file.path) -#+END_SRC - -Resolving subproperties makes use of the "resolve_reference" function provided by the high level -entity class (~CaosDBPythonEntity~), with the following parameters: -- ~deep~: Whether to use recursive retrieval -- ~references~: Whether to use the supplied db.Container to resolve references. This allows offline usage. Set it to None if you want to automatically retrieve entities from the current CaosDB connection. -- ~visited~: Needed for recursion, set this to None. - -Objects in the high level representation can be serialized to a simple yaml form using the function -~serialize~ with the following parameters: -- ~without_metadata~: Set this to True if you don't want to see property metadata like "unit" or "importance". -- ~visited~: Needed for recursion, set this to None. - -This function creates a simple dictionary containing a representation of the entity, which can be -stored to disk and completely deserialized using the function ~deserialize~. - -Furthermore the "__str__" function is overloaded, so that you can use print to directly inspect -high level objects using the following statement: -#+BEGIN_SRC python -print(str(obj)) -#+END_SRC - - -** Concepts - -As described in the section [[Quickstart]] the two functions ~convert_to_python_object~ and ~convert_to_entity~ convert -entities beetween the high level and the standard representation. - -The high level entities are represented using the following classes from the module ~caosdb.high_level_api~: -- ~CaosDBPythonEntity~: Base class of the following entity classes. -- ~CaosDBPythonRecord~ -- ~CaosDBPythonRecordType~ -- ~CaosDBPythonProperty~ -- ~CaosDBPythonMultiProperty~: **WARNING** Not implemented yet. -- ~CaosDBPythonFile~: Used for file entities and provides an additional ~download~ function for being able to directly retrieve files from CaosDB. - -In addition, there are the following helper structures which are realized as Python data classes: -- ~CaosDBPropertyMetaData~: For storing meta data about properties. -- ~CaosDBPythonUnresolved~: The base class of unresolved "things". -- ~CaosDBPythonUnresolvedParent~: Parents of entities are stored as unresolved parents by default, storing an id or a name of a parent (or both). -- ~CaosDBPythonUnresolvedReference~: An unresolved reference is a reference property with an id which has not (yet) been resolved to an Entity. - -The function "resolve_references" can be used to recursively replace ~CaosDBPythonUnresolvedReferences~ into members of type ~CaosDBPythonRecords~ -or ~CaosDBPythonFile~. - -Each property stored in a CaosDB record corresponds to: -- a member attribute of ~CaosDBPythonRecord~ **and** -- an entry in a dict called "metadata" storing a CaosDBPropertyMetadata object with the following information about proeprties: - - ~unit~ - - ~datatype~ - - ~description~ - - ~id~ - - ~importance~ -- GitLab