[DOC] A doc page for the extract API

This doc page details the extract API and has the following structure:

- Service explanation.
- Expected successful flow
- Description of the 3 routes (request and response structure)
	- /parse
	- /get_results
	- /validate
- Hint for integration testing

closes odoo/odoo#61051

Signed-off-by: Florian Daloze (fda) <fda@odoo.com>

6 files changed, 673 insertions, 0 deletions

diff --git a/doc/_extensions/odoo_ext/translator.py b/doc/_extensions/odoo_ext/translator.py
index 982e6040c44..914d0a81313 100644
--- a/doc/_extensions/odoo_ext/translator.py
+++ b/doc/_extensions/odoo_ext/translator.py
@@ -515,6 +515,20 @@ class BootstrapTranslator(nodes.NodeVisitor, object):
         self.body.append(self.starttag(node, 'a', **attrs))
     def depart_reference(self, node):
         self.body.append(u'</a>')
+    def visit_download_reference(self, node):
+        # type: (nodes.Node) -> None
+        if node.hasattr('filename'):
+            self.body.append(
+                '<a class="reference download internal" href="%s" download="">' %
+                posixpath.join(self.builder.dlpath, node['filename']))
+            self.body.append(node.astext())
+            self.body.append('</a>')
+            raise nodes.SkipNode
+        else:
+            self.context.append('')
+    def depart_download_reference(self, node):
+        # type: (nodes.Node) -> None
+        self.body.append(self.context.pop())
     def visit_target(self, node): pass
     def depart_target(self, node): pass
     def visit_footnote(self, node):
diff --git a/doc/_static/banners/extract_api.jpg b/doc/_static/banners/extract_api.jpg
new file mode 100644
index 00000000000..c58a958f2d0
--- /dev/null
+++ b/doc/_static/banners/extract_api.jpg
diff --git a/doc/_static/banners/extract_api.small.jpg b/doc/_static/banners/extract_api.small.jpg
new file mode 100644
index 00000000000..435e37369d0
--- /dev/null
+++ b/doc/_static/banners/extract_api.small.jpg
diff --git a/doc/_static/extract_api_implementation.py b/doc/_static/extract_api_implementation.py
new file mode 100644
index 00000000000..bb2a8bca629
--- /dev/null
+++ b/doc/_static/extract_api_implementation.py
@@ -0,0 +1,100 @@
+import base64
+import time
+import sys
+import json
+import requests
+
+account_token = "integration_token"  # Use your token
+domain_name = "https://iap-extract.odoo.com"
+path_to_pdf = "/path/to/invoice_file"
+
+API_VERSION = 120  # Do not change
+SUCCESS = 0
+NOT_READY = 1
+
+def jsonrpc(path, params):
+    payload = {
+        'jsonrpc': '2.0',
+        'method': 'call',
+        'params': params,
+        'id': 0,
+    }
+    req = requests.post(domain_name+path, json=payload, timeout=10)
+    req.raise_for_status()
+    resp = req.json()
+    return resp
+
+
+with open(path_to_pdf, "rb") as file:
+    params = {
+        'account_token': account_token,
+        'version': API_VERSION,
+        'documents': [base64.b64encode(file.read()).decode('ascii')],
+    }
+
+response = jsonrpc("/iap/invoice_extract/parse", params)
+print("/parse call status: ", response['result']['status_msg'])
+
+if response['result']['status_code'] != SUCCESS:
+    sys.exit(1)
+
+# You received an id that you can use to poll the server to get the result of the ocr when it will be ready
+document_id = response['result']['document_id']
+params = {
+    'version': API_VERSION,
+    'document_ids': [document_id],  # you can request the results of multiple documents at once if wanted
+}
+
+response = jsonrpc("/iap/invoice_extract/get_results", params)
+document_id = str(document_id) # /get_results expects a string despite the fact that the returned document_id is a int
+
+while response['result'][document_id]['status_code'] == NOT_READY:  # 1 is the status code indicating that the server is still processing the document
+    print("Still processing... Retrying in 5 seconds")
+    time.sleep(5)
+    response = jsonrpc("/iap/invoice_extract/get_results", params)
+
+with open('results.txt', 'w') as outfile:
+    json.dump(response, outfile, indent=2)
+print("\nResult saved in results.txt")
+
+if response['result'][document_id]['status_code'] != SUCCESS:
+    print(response['result'][document_id]['status_msg'])  # if it isn't a success, print the error message
+    sys.exit(1)
+
+document_results = response['result'][document_id]['results'][0]
+print("\nTotal:", document_results['total']['selected_value']['content'])
+print("Subtotal:", document_results['subtotal']['selected_value']['content'])
+print("Invoice id:", document_results['invoice_id']['selected_value']['content'])
+print("Date:", document_results['date']['selected_value']['content'])
+print("...\n")
+
+params = {
+    'document_id': document_id,
+    'values': {
+        'total': {'content': 100.0},
+        'subtotal': {'content': 100.0},
+        'global_taxes': {'content': []},
+        'global_taxes_amount': {'content': 0.0},
+        'date': {'content': '2020-09-25'},
+        'due_date': {'content': '2020-09-25'},
+        'invoice_id': {'content': document_results['invoice_id']['selected_value']['content']},
+        'partner': {'content': 'twinnta'},
+        'VAT_Number': {'content': 'BE23252248420'},
+        'currency': {'content': 'USD'},
+        'merged_lines': False,
+        'invoice_lines': {'lines': [{'description': 'Total TVA ',
+                                        'quantity': 1.0,
+                                        'unit_price': 100.0,
+                                        'product': False,
+                                        'taxes_amount': 0.0,
+                                        'taxes': [],
+                                        'subtotal': 100.0,
+                                        'total': 100.0}]
+                            }
+    }
+}
+response = jsonrpc("/iap/invoice_extract/validate", params)
+if response['result']['status_code'] == SUCCESS:
+    print("/validate call status: Success")
+else:
+    print("/validate call status: wrong format")
diff --git a/doc/webservices.rst b/doc/webservices.rst
index 3af3a363902..3dac7fa947d 100644
--- a/doc/webservices.rst
+++ b/doc/webservices.rst
@@ -12,3 +12,4 @@ Web Services
     webservices/iap
     webservices/upgrade
     webservices/localization
+    webservices/extract_api
\ No newline at end of file
diff --git a/doc/webservices/extract_api.rst b/doc/webservices/extract_api.rst
new file mode 100644
index 00000000000..f79a3ff2484
--- /dev/null
+++ b/doc/webservices/extract_api.rst
@@ -0,0 +1,558 @@
+:banner: banners/extract_api.jpg
+:types: api
+
+:code-column:
+
+===============
+Extract API
+===============
+
+Odoo provides a service allowing you to automate the processing of your invoices. The service scans your document using an Optical
+Character Recognition (OCR) engine and then uses AI-based algorithms to extract the fields of interest such as the total, the due date, or
+the invoice lines. More functional information can be found on the `demo page <https://www.odoo.com/page/invoice-automation>`_.
+
+This service is a paid service. Each invoice processing will cost you one credit. Three different sized packs can be bought on `iap.odoo.com <https://iap.odoo.com/iap/in-app-services/259?sortby=date>`_.
+
+You can either use this service directly in the Odoo Accounting App or through the API. The Extract API which is detailed in the next section
+allows you to integrate our service directly into your own projects.
+
+Invoices
+========
+The extract API use the JSON-RPC2_ protocol. The diffent routes are located at the following address: **https://iap-extract.odoo.com**.
+
+Expected successful flow
+------------------------
+
+1. Call :ref:`webservices/extract_api/invoice_parse` to submit your invoices (one call for each invoice). On success, you receive a `document_id` in the response. 
+2. You then have to regularly poll :ref:`webservices/extract_api/invoice_get_results` to get the document's parsing status.
+3. Once the result received, you can validate it by calling :ref:`webservices/extract_api/invoice_validate` and sending the expected values. 
+   This step is optional but greatly helps the system to improve.
+
+These 3 routes are detailed in this :ref:`section <webservices/extract_api/routes>`. The HTTP POST method should be used for all of them. A python implementation of the full flow
+can be found :download:`here </_static/extract_api_implementation.py>` and a token for integration testing is provided in the :ref:`integration testing section <webservices/extract_api/integration_testing>`.
+
+.. _webservices/extract_api/routes:
+
+Routes
+------
+
+.. _webservices/extract_api/invoice_parse:
+
+``/iap/invoice_extract/parse``
+''''''''''''''''''''''''''''''
+
+Description
+^^^^^^^^^^^
+Request a processing of the document from the OCR. The route will return a `document_id` you can use to obtain the result of your request.
+
+Request Body
+^^^^^^^^^^^^
+
+``jsonrpc`` (required)
+    Must be exactly “2.0”.
+``method`` (required)
+    Must be “call”.
+``id`` (required)
+    An identifier established by the client. It allows the client to keep track of which response goes with which request. This makes asynchronous calls easier.
+``params``
+    ``account_token`` (required)
+        The token of the account from which credits will be taken. Each successful call costs one token.
+    ``version`` (optional)
+        The version will determine the format of your requests and the format of the server response. Some results can be unavailable in older versions. For the current
+        version 1.2.0, send ‘120’. If not specified, the latest version will be used.
+    ``documents`` (required)
+        The invoice must be provided as a string in the ASCII encoding. The list should contain only one string. If multiple strings are provided only the first string 
+        corresponding to a pdf will be processed. If no pdf is found, the first string will be processed. This field is a list only for legacy reasons. The supported extensions 
+        are *pdf*, *png*, *jpg* and *bmp*.
+    ``user_infos`` (required)
+        Information concerning the person to whom the invoice is intended. This informations is not required in order for the service to work but it greatly improves the quality of the result.
+        
+        ``user_company_vat`` (optional)
+            VAT number of the client.
+        ``user_company_name`` (optional)
+            Name of the client’s company.
+        ``user_company_country_code`` (optional)
+            Country code of the client. Format: `ISO3166 alpha-2 <https://www.iban.com/country-codes>`_.
+        ``user_lang`` (optional)
+            The client language. Format: *language_code + _ + locale* (ex: fr_FR, en_US).
+        ``user_email`` (optional)
+            The client email.
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+            {
+                "jsonrpc": string,
+                "method": string,
+                "params": {
+                        "account_token": string (hex),
+                        "version": int,
+                        "documents": [string],
+                        "user_infos": {
+                                "user_company_vat": string,
+                                "user_company_name": string,
+                                "user_company_country_code": string,
+                                "user_lang": string,
+                                "user_email": string,
+                        },
+                },
+                "id": string (hex),
+            }
+
+Response
+^^^^^^^^
+
+``jsonrpc``
+    A string specifying the version of the JSON-RPC protocol. It will be “2.0”.
+``id``
+    The identifier you set in the request body.
+``result``
+    ``status_code``
+        |STATUS_CODE|
+    ``status_msg``
+        |STATUS_MSG|
+    ``document_id``
+        Only present if the request is successful.
+
+.. note::  The API does not actually use the JSON-RPC error scheme. Instead the API has its own error scheme bundled inside a successful JSON-RPC result.
+
+=============  ==============================================================
+ status_code       status_msg
+=============  ==============================================================
+0              Success
+2              An error occured
+3              You don't have enough credit
+6              Unsupported file format
+9              Server is currently under maintenance. Please try again later.
+=============  ==============================================================
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {
+            "jsonrpc": string,
+            "id": string,
+            "result": {
+                "status_code": int,
+                "status_msg": string,
+                "document_id": int,
+            }
+        }
+
+
+.. _webservices/extract_api/invoice_get_results:
+
+``/iap/invoice_extract/get_results``
+''''''''''''''''''''''''''''''''''''
+
+Description
+^^^^^^^^^^^
+Request the results of the documents ids obtained with the :ref:`/parse <webservices/extract_api/invoice_parse>` route. Can either return the results or a "request pending" message.
+
+Request Body
+^^^^^^^^^^^^
+
+``jsonrpc`` (required)
+    |SAME_AS_PARSE|
+``method`` (required)
+    |SAME_AS_PARSE|
+``id`` (required)
+    |SAME_AS_PARSE|
+``params``:
+    ``version`` (required)
+        |SAME_AS_PARSE|
+    ``documents_ids`` (required)
+        The list of ``document_id`` for which you want to get the current parsing status.
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {
+            "jsonrpc": string,
+            "method": string,
+            "params": {
+                "version": int,
+                "documents_ids": [int]
+            },
+            "id": string (hex),
+        }
+
+
+Response
+^^^^^^^^
+
+``jsonrpc``
+    |SAME_AS_PARSE|
+``id``
+    |SAME_AS_PARSE|
+``result``
+    Dictionary where each key is a document_id. For each ``document_id``:
+
+    ``status_code``
+        |STATUS_CODE|
+    ``status_msg``
+        |STATUS_MSG|
+    ``results``
+        Only present if the request is successful.
+
+.. warning:: result keys are strings despite the fact that the document_ids given in the request body are integers.
+
+=============  ==============================================================
+ status_code       status_msg
+=============  ==============================================================
+0              Success
+1              Not ready
+2              An error occured
+9              Server is currently under maintenance. Please try again later.
+=============  ==============================================================
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {
+            "jsonrpc": string,
+            "id": string,
+            "result": {
+                "document_id_1": {
+                    "status_code": int,
+                    "status_msg": str,
+                    "results": [{"feature_1_name": feature_1_result, 
+                                 "feature_2_name": feature_2_result,
+                                 …
+                                }]
+                    },
+                "document_id_2": {
+                    "status_code": int,
+                    "status_msg": str,
+                    "results": [{"feature_1_name": feature_1_result, 
+                                 "feature_2_name": feature_2_result,
+                                 …
+                                }]
+                    },
+                    ...
+            }
+        }
+
+.. _webservices/extract_api/invoice_get_results/feature_result:
+
+``feature_result``
+''''''''''''''''''
+
+Each field of interest we want to extract from the invoice such as the total or the due date are also called features. An exhaustive list of all the extracted features can be found in the table below.
+
+For each feature, we return a list of candidates and we spotlight the candidate our model predicts to be the best fit for the feature.
+
+``selected_value``
+    The best candidate for this feature.
+``words``
+    List of all the candidates for this feature ordered by decreasing score.
+
+.. container:: doc-aside
+
+    .. switcher::
+
+        .. code-block:: json
+
+            {
+                "selected_value": candidate_12,
+                "words": [candidate_12, candidate_3, candidate_4,...]
+            }
+
+
+``candidate``
+'''''''''''''
+
+For each candidate we give its representation and position in the document. Candidates are sorted by decreasing order of suitability.
+
+``content``
+    Representation of the candidate.
+``coords``
+    ``[center_x, center_y, width, height, rotation_angle]``. The position and dimensions are relative to the size of the page and are therefore between 0 and 1.
+    The angle is a clockwise rotation measured in degrees.  
+``page``
+    Page of the original document on which the candidate is located (starts at 0).
+
+.. container:: doc-aside
+
+    .. switcher::
+
+        .. code-block:: json
+
+            {
+                "content": string|float,
+                "coords": [float, float, float, float, float],
+                "page": int
+            }
+
++-------------------------+------------------------------------------------------------------------------------+
+| Feature name            | Specifities                                                                        |
++=========================+====================================================================================+
+| ``SWIFT_code``          | **content** is a dictionary encoded as a string.                                   |
+|                         |                                                                                    |
+|                         | It contains information about the detected SWIFT code                              |
+|                         | (or `BIC <https://www.iso9362.org/isobic/overview.html>`_).                        |
+|                         |                                                                                    |
+|                         | Keys:                                                                              |
+|                         |                                                                                    |
+|                         | ``bic``                                                                            |
+|                         |     detected BIC (string).                                                         |
+|                         | ``name`` (optional)                                                                |
+|                         |     bank name (string).                                                            |
+|                         | ``country_code``                                                                   |
+|                         |     ISO3166 alpha-2 country code of the bank (string).                             |
+|                         | ``city`` (optional)                                                                |
+|                         |     city of the bank (string).                                                     |
+|                         | ``verified_bic``                                                                   |
+|                         |     True if the BIC has been found in our DB (bool).                               |
+|                         |                                                                                    |
+|                         | Name and city are present only if verified_bic is true.                            |
++-------------------------+------------------------------------------------------------------------------------+
+| ``VAT_Number``          | **content** is a string                                                            |
++-------------------------+------------------------------------------------------------------------------------+
+| ``country``             | **content** is a string                                                            |
++-------------------------+------------------------------------------------------------------------------------+
+| ``currency``            | **content** is a string                                                            |
++-------------------------+------------------------------------------------------------------------------------+
+| ``date``                | **content** is a string                                                            |
+|                         |                                                                                    |
+|                         | Format : *YYYY-MM-DD HH:MM:SS*                                                     |
++-------------------------+------------------------------------------------------------------------------------+
+| ``due_date``            | Same as for ``date``                                                               |
++-------------------------+------------------------------------------------------------------------------------+
+| ``global_taxes``        | **content** is a float                                                             |
+|                         |                                                                                    |
+|                         | **candidate** has an additional field ``amount_type``. Its value is always percent.|
+|                         |                                                                                    |
+|                         | **selected_values** is a list of candidates.                                       |
++-------------------------+------------------------------------------------------------------------------------+
+| ``global_taxes_amount`` | **content** is a float                                                             |
++-------------------------+------------------------------------------------------------------------------------+
+| ``invoice_id``          | **content** is a string                                                            |
++-------------------------+------------------------------------------------------------------------------------+
+| ``subtotal``            | **content** is a float                                                             |
++-------------------------+------------------------------------------------------------------------------------+
+| ``total``               | **content** is a float                                                             |
++-------------------------+------------------------------------------------------------------------------------+
+| ``supplier``            | **content** is a string                                                            |
++-------------------------+------------------------------------------------------------------------------------+
+
+``feature_result`` for the ``invoice_lines`` feature
+''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+It follows a more specific structure. It is basically a list of dictionaries where each dictionary represents an invoice line. Each value follows 
+a :ref:`webservices/extract_api/invoice_get_results/feature_result` structure.
+
+.. container:: doc-aside
+
+    .. switcher::
+
+        .. code-block:: json
+
+            [
+                {
+                    "description": feature_result,
+                    "discount": feature_result,
+                    "product": feature_result,
+                    "quantity": feature_result,
+                    "subtotal": feature_result,
+                    "total": feature_result,
+                    "taxes": feature_result,
+                    "total": feature_result,
+                    "unit": feature_result,
+                    "unit_price": feature_result
+                },
+                ...
+            ]
+
+.. _webservices/extract_api/invoice_validate:
+
+``/iap/invoice_extract/validate``
+'''''''''''''''''''''''''''''''''
+
+Description
+^^^^^^^^^^^
+Route that validates the different features of an invoice. The validation step is an optional step but is strongly recommended. By telling the system if it were right or wrong for each
+feature you give an important feedback. It has no direct impact but it helps the system to greatly improve its prediction accuracy for the invoices you will send in the future.
+
+Request Body
+^^^^^^^^^^^^
+
+``jsonrpc`` (required)
+    |SAME_AS_PARSE|
+``method`` (required)
+    |SAME_AS_PARSE|
+``params``
+    ``documents_id`` (required)
+        Id of the document for which you want to validate the result.
+    ``values``
+        Contains the validation for each feature. The field ``merged_line`` indicates if the ``invoice_lines`` have been merged or not.
+
+.. note:: You don't have to validate all the features in order for the validation to succeed. However :ref:`/validate <webservices/extract_api/invoice_validate>` can't be called multiple times for a same invoice.
+          Therefore you should validate all the features you want to validate at once.
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {
+            "jsonrpc": string,
+            "method": string,
+            "params": {
+                "document_id": int,
+                "values": {
+                    "merged_lines": bool
+                    "feature_name_1": validation_1,
+                    "feature_name_2": validation_2,
+                    ...
+                }
+            },
+            "id": string (hex),
+        }
+
+``validation`` 
+''''''''''''''
+
+A **validation** for a given feature is a dictionary containing the textual representation of the expected value for this given feature.
+This format apply for all the features except for ``global_taxes`` and ``invoice_lines`` which have more complex validation format.
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        { "content": string|float }
+
+validation for ``global_taxes``
+'''''''''''''''''''''''''''''''
+
+**content** is a list of dictionaries. Each dictionary represents a tax:
+
+``amount``
+    Amount on which the tax is applied.
+``tax_amount``
+    Amount of the tax.
+``tax_amount_type``
+    Indicates if the ``tax_amount`` is a percentage or a fixed value. The type must be specified using the literal string "fixed" or "percent".
+``tax_price_include``
+    Indicates if ``amount`` already contains the tax or not. 
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {"content": [
+            {
+                "amount": float,
+                "tax_amount": float,
+                "tax_amount_type": "fixed"|"percent",
+                "tax_price_include": bool
+            },
+            ...
+        ]}
+
+validation for ``invoice_lines``
+''''''''''''''''''''''''''''''''
+
+**lines** is a list of dictionaries. Each dictionary represents an invoice line. The dictionary keys speak for themselves.
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {"lines": [
+            {
+                "description": string,
+                "quantity": float,
+                "unit_price": float,
+                "product": string,
+                "taxes_amount": float,
+                "taxes": [
+                            {
+                                "amount": float, 
+                                "type": "fixed"|"percent", 
+                                "price_include": bool
+                            },
+                            ...
+                        ],
+                "subtotal": float,
+                "total": float
+            },
+            ...
+        ]}
+
+Response
+--------
+
+``jsonrpc``
+    |SAME_AS_PARSE|
+``id``
+    |SAME_AS_PARSE|
+``result``
+    ``status_code``
+        |STATUS_CODE|
+    ``status_msg``
+        |STATUS_MSG|
+
+=============  ==========================================================
+ status_code       status_msg
+=============  ==========================================================
+0              Success
+12             Validation format is incorrect
+=============  ==========================================================
+
+.. rst-class:: setup doc-aside
+
+.. switcher::
+
+    .. code-block:: json
+
+        {
+            "jsonrpc": string,
+            "id": string,
+            "result": {
+                "status_code": int,
+                "status_msg": string,
+            }
+        }
+
+
+.. _webservices/extract_api/integration_testing:
+
+Integration Testing 
+===================
+
+You can test your integration by using *integration_token* as ``account_token`` in the :ref:`/parse <webservices/extract_api/invoice_parse>` request.
+
+Using this token put you in test mode and allows you to simulate the entire flow without really parsing a document and without being billed one credit for each successful invoice parsing.
+
+The only technical differences in test mode is that the document you send is not parsed by the system and that the response you get from :ref:`/get_results <webservices/extract_api/invoice_get_results>`
+is a hard-coded one. 
+
+A python implementation of the full flow can be found :download:`here </_static/extract_api_implementation.py>`.
+
+.. _JSON-RPC2: https://www.jsonrpc.org/specification
+
+.. |SAME_AS_PARSE| replace:: Same as for :ref:`/parse <webservices/extract_api/invoice_parse>`.
+
+.. |STATUS_CODE| replace:: The code indicating the status of the request. ``status_code`` is 0 in case of success. Other ``status_code`` are detailed in the table below.
+
+.. |STATUS_MSG| replace:: A string giving verbose details about the request status.
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