How to add Bangla Taka (৳) currency symbol in WkHTMLtoPdf / Odoo / OpenERP Qweb Report

WkHTMLtoPDF is a tool to convert html reports to PDF. Odoo/OpenERP uses this tool to generate PDF reports. If you are using an unicode character in PDF report, that character has to be installed in font package in the system. If you are using Windows, Bangla characters are available by default. But that is not same for Linux.

Bangla & Assamese fonts are available for Linux, in a package called ‘lohit’.

To install Bangla fonts in CentOS/Redhat based system, use the following:

yum install lohit-bengali-fonts

To install in Debian/Ubuntu based system, use the following:

apt install fonts-lohit-beng-bengali

Once this is installed, PDF reports should start showing the Bangla characters properly.

Happy shooting!

How to manipulate time in Odoo Qweb Report

In Odoo Qweb report, you probably want to change the time to something else, like add few hours, or change the timezone, or so on. To do that, you would need to use ‘t-esc’ template attribute of Odoo. Here is an example of how to add 6 hours to the original timestamp and then convert the time to string to show the value according to the user preference:

<span t-esc="(o.date_done + datetime.timedelta(hours=6)).strftime('%d/%m/%Y %I:%M %p')"/>

o.date_done is getting the date_done from the picking that you are visiting.

Odoo Time Showing in Form View does not match Time in Qweb Report – Timezone Mismatch


You are seeing a time in the Odoo form view, which is using the correct timezone, but when you try to download the report of the same form view data, you see, the timezone is changed to UTC or something else. How to fix this?


The issue appears when the user has configured a different timezone or has not, while the Odoo system uses a central timezone. Make sure to set the timezone for the user to same as the one Odoo uses. You may do so, from

Odoo >> Settings >> Users >> Select User >> Edit >> Preference >> Set Timezone

If this does not solve the problem, then the problem probably appears because Odoobot is set to use a different timezone, and your report is generated using ‘sudo()’ function. To set the timezone for Odoobot

Odoo >> Settings >> Users >> From the Filters, select ‘Inactive Users’ >> Click on Odoobot >> Edit >> Preference >> Set the Timezone

Hope this helps.

How to Install Odoo 15 in CentOS 7 – Troubleshooting Recent Errors

Installing Odoo 15 along with the CentOS 7 and the latest PGSQL repo has changed pretty a lot. I will try to cover solutions to a few errors along with the straightforward steps on installing Odoo 15 in CentOS 7.

First Step First

Update your CentOS 7 installation and install Epel-release

yum update -y
yum install epel-release

Install Python 3.8

We will use Python 3.8 for Odoo 15. We will use Software Collection Repository or SCL to install our Python binary. You may find details of SCL here:

SCL Repository

First, install SCL in CentOS:

yum install centos-release-scl -y

Once done, you can now install Python 3.8 using the following:

yum install rh-python38 -y

Also, install python38-devel as Python.h is used to compile psycopg2 and python-ldap package. From Odoo 15, you need this to get going:

yum install rh-python38-python-devel -y

Note: The above is used to resolve an error like the following

fatal error: Python.h: No such file or directory

Now, we will install a few prerequisites to install Odoo 15. One difference between the old version installed and the new is that you need to load GCC-c+ now along with the GCC compiler. Otherwise, you will see an error like the following:

gcc: error trying to exec ‘cc1plus’: execvp: No such file or directory

So, to install the pre-requisites, run the following:

yum install git gcc nano wget nodejs-less libxslt-devel bzip2-devel openldap-devel libjpeg-devel freetype-devel gcc-c++ -y

Once done, now, you can create the user odoo:

useradd -m -U -r -d  /opt/odoo -s /bin/bash odoo

We are done with the primary setup, now we move to install database

Install PostgreSQL 13 in CentOS 7

To install PGSQL 13 in CentOS 7, you need to first install the pgsql official repository. You may install this using the following:

yum -y install

Once done, now you can install PostgreSQL 13 and related things:

yum install postgresql13 postgresql13-server postgresql13-contrib postgresql13-libs -y

Once done, now can you initiate the PostgreSQL and start the database server

/usr/pgsql-13/bin/postgresql-13-setup initdb
systemctl start postgresql-13.service
systemctl enable postgresql-13.service

# create the postgres user odoo
su - postgres -c "createuser -s odoo"

Brilliant, now, one more additional thing we need to resolve. With the latest Postgresql 13, you might still not be able to use the libpq. You need to install it manually. Otherwise, you will see an error like the following:

fatal error: libpq-fe.h: No such file or directory

To resolve this error, you need to install these libraries manually with the following command:

yum install libpq5 libpq5-devel -y

Remember to install libpq5-devel as the source of the libpq would be used to compile psycopg2.

Install Wkhtmltox

Now, let’s move to the next step of installing wkhtmltox. The version for wkhtmltox has remained the same for pretty long. The following shall work till now:

cd /opt
yum localinstall wkhtmltox-0.12.6-1.centos7.x86_64.rpm

This specific tool is used to generate reports in Odoo, without this, you might not be able to use pdf/html reports using Qweb in Odoo.

Final Step: Install and Configure Odoo 15

We will here download the source from Github and install all the dependent packages. First, we switch to the user odoo

su - odoo

Now, clone the git repo for Odoo 15 to a folder odoo15 using the following:

git clone --depth 1 --branch 15.0 /opt/odoo/odoo15

Once done, now, we can enable python3.8 and create a virtual environment for our Odoo installation. First, enable the Python3.8 using scl:

scl enable rh-python38 bash

Now create a virtual environment for our Odoo15 installation:

cd /opt/odoo
python3 -m venv odoo15-venv

Activate the virtual environment we just created

source odoo15-venv/bin/activate

Now, we upgrade the pip and install wheel package:

pip install --upgrade pip
pip3 install wheel

Now, before we can install the requirements file using pip3 package installer, here is an error you will face when compiling psycopg2

Error: pg_config executable not found.

Now the problem is understandable, pg_config file is usually placed under the binary folder of pgsql which is:


For some reason, our installer fails to identify this. To solve the issue, we first, load this in the $PATH variable before running pip3 for requirements.

export PATH=/usr/pgsql-13/bin/:$PATH

Now, you can run the pip3 installer:

pip3 install -r odoo15/requirements.txt

This shall be complete without any error if you have solved the solutions I had given above. If any of them are missed, you should double-check all the mentioned errors above.

Now exit the venv:

deactivate && exit ; exit

Now, the first step for configuration, edit the /etc/odoo.conf file

nano /etc/odoo.conf

Paste the following:

; This is the password that allows database operations:
admin_passwd = set_the_password_to_create_odoo_database
db_host = False
db_port = False
db_user = odoo
db_password = False
addons_path = /opt/odoo/odoo15/addons
; You can enable log file with uncommenting the next line
; logfile = /var/log/odoo15/odoo.log

Replace ‘set_the_password_to_create_odoo_database’ with the one you want to use to allow odoo installer to create the database for you.

Odoo15 Service File

Now, we will create a service file to start/stop/restart our Odoo 15 installation.

nano /etc/systemd/system/odoo15.service

Paste the following:

Requires=postgresql-13.service postgresql-13.service

ExecStart=/usr/bin/scl enable rh-python38 -- /opt/odoo/odoo15-venv/bin/python3 /opt/odoo/odoo15/odoo-bin -c /etc/odoo.conf


We are now done with the service installation.

Now reload the system daemon:

systemctl daemon-reload

Finally, now we can start Odoo 15 with the following:

systemctl start odoo15

Check the status:

[root@cloud-accounts ~]# systemctl status odoo15
● odoo15.service - Odoo15
   Loaded: loaded (/etc/systemd/system/odoo15.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2021-12-27 08:47:30 EST; 42min ago
 Main PID: 5012 (scl)
   CGroup: /system.slice/odoo15.service
           ├─5012 /usr/bin/scl enable rh-python38 -- /opt/odoo/odoo15-venv/bin/python3 /opt/odoo/odoo15/odoo-bin -c /etc/odoo.conf
           ├─5013 /bin/bash /var/tmp/sclAlWADi
           └─5016 /opt/odoo/odoo15-venv/bin/python3 /opt/odoo/odoo15/odoo-bin -c /etc/odoo.conf

Dec 27 08:47:30 cloud-accounts systemd[1]: Started Odoo15.

You can enable the Odoo15 when the system reboots

systemctl enable odoo15

Now, if you want to enable logging, uncomment the following line from /etc/odoo.conf

logfile = /var/log/odoo15/odoo.log

If everything goes right, you should now be able to access the Odoo in port 8069:


How to get purchase_id from stock_picking table in Odoo?

stock_picking is one of the core model for Odoo if you using Odoo for ‘Inventory’. Now, if you use ‘Sales’ module, then stock_picking would be extended with a new field for model and column for database table, naming ‘sale_id’. This can be used to detect if the picking is originated from a sale order or not. But if you install ‘Purchase’ module, then stock_picking model is extended with ‘purchase_id’ like the ‘sale_id’ for purchases, but the database isn’t expanded with a column like ‘Sale’ module.

What does this mean?

This means, if you use Odoo ORM, only then, you may use purchase_id of a stock_picking. An example could be like the following. Let’s say, we would like to pick the pickings that originated from purchase orders, aka, GRN, we could use something like this:

purchase_pickings = self.env['stock.picking'].search([('purchase_id', '!=', False)])

This works, only if you are not trying to make a report from a huge lot of pickings, purchase orders and sale orders, when you want to use SQL statement to produce efficient joins and generate the report quickly.

Let me demonstrate what I meant

We know, stock_picking has a field called sale_id and also this also belongs to the database column as well. Hence, to get all the pickings belongs to sale order, we may first use the ORM:

sale_pickings = self.env['stock.picking'].search([('sale_id', '!=', False)])

or a direct PostGRE SQL

query = """select * from stock_picking where sale_id is not null"""
result =

Now, the second example is not only faster, but also, it allows you to extend the facility further to use joins or select specific field of a table result, which is only possible using ‘read’ Odoo ORM method, again, domain specification is not permissible like it is available in ‘search’.

We are able to do things like the following with the sql:

query = """select, from stock_picking left join on stock_picking.sale_id = where stock_picking.sale_id is not null"""
result =

This would give you a result of each sale order with it’s picking name. To produce a result like the above using ORM is costly as it follows ‘N+1’ algorithm, hence inefficient in making reports or scaling the software.

Now, we understand, we are able to use such field and make the reports efficient using SQL as sale_id is distinctively available in the database. But what if you want to check how the product has been purchased, and then sold? Then, we also need purchase_order model to connect to our above query, right? But unfortunately, as ‘Purchase’ module doesn’t add a column purchase_id, we are unable to use this directly.

So, how can we still use purchase_id in the SQL Query to generate report in Odoo?

First, we need to see, how purchase_id is added in Odoo.

purchase_id is added in stock_picking model in the ‘purchase_stock’ module. If you open the following file:


you may see, how purchase_id is defined as related Many2one field:

class StockPicking(models.Model):
    _inherit = 'stock.picking'

    purchase_id = fields.Many2one('purchase.order', related='move_lines.purchase_line_id.order_id',
        string="Purchase Orders", readonly=True)

A related field in Odoo, is like a pointer, a syntactic sugar of foreign key for less used fields. If the field is highly used, this might cause performance issue, as Odoo has to do multiple lookups unlike direct lookup for a related field. Now, get to the point, purchase_id is related to ‘move_lines.purchase_line_id.order_id’. This is a long relation. Let me go one by one:

  1. move_lines : stock_picking has an One2many relation with stock.move model, that derives the available moves for the picking.
  2. purchase_line_id: Each move line derived from a purchase order line, and while doing so, it keeps the ID of the purchase order line in a foreign key of stock.move model, namely purchase_line_id.
  3. order_id: Each purchase_order_line has a foreign key with the purchase.order model kept in order_id field.

Now, we know, how the purchase_id derives the purchase_order id using the following relation:

Picking > Moves > Purchase Order Line > Purchase Order

Now we can use the following kind of relation for detecting purchase order from stock picking:

select, from stock_picking left join stock_move on stock_move.picking_id = left join purchase_order_line on = stock_move.purchase_line_id left join purchase_order on = purchase_order_line.order_id where stock_move.purchase_line_id is not null group by,

Here, we are able to get the picking and purchase in relation with one query. This concept can be used to derive many data, like, let’s say, you would like to see, how many of your products are purchased, then, sold and returned, all can be done in few queries, without having N+1 problem.

How to Fix Locale Font Issue with Odoo Qweb Reports


When looking at the html report in Odoo, locale fonts look ok, but if you download the Qweb report to print in pdf format, it prints gibberish. How to fix that?


Odoo uses a templating engine for reporting called ‘Qweb’. Qweb can be used to generate two types of reports. One is HTML and the other is PDF. Odoo primarily uses Qweb engine to generate the HTML code. After that, it uses a tool called ‘wkhtmltopdf’ to convert the report to pdf and make it printable. Now when, we look at the HTML version of the report, fonts are shown based on Unicode supported browsers or the fonts you have installed on your computer. But when you try to convert this to PDF using wkhtmltopdf, that tool has to have exclusive access to those fonts to be able to convert them from HTML to pdf for you. As wkhtmlpdf command runs in the server you have installed Odoo, hence, you would need to install the font package in the server.

In my case, I required to install Bengali fonts. For CentOS, it is available under the lohit package, that contains several indian fonts including bengali. To install bengali font package in CentOS 7, use the following command:

yum install lohit-bengali* -y

Once done, your wkhtmltopdf should be able to read the bengali fonts from your html/qweb templates and able to convert them to PDF for you.

How to Add fields to res.users or model in Odoo

res.users and tables are two base tables of odoo. If you would like to inherit and extend them, remember, you can’t do it from the Odoo user view. The reason is, when you do an upgrade from the user view, it has to be something that works over base module, not base module itself. Hence, you will get a 500 error or internal server error when trying to upgrade the module.

We will make a simple module for res.users to extend the model to add a field called ‘access_token’ for each user, and generate a key automatically when a user is added.

I will only post the model file and the view file here. I expect you already know how to write an Odoo module.

This is my file

from odoo import api, fields, models
import string, random

class res_users_ex(models.Model):
    _inherit = 'res.users'

    access_token = fields.Text(string='API Access Token', default=False)

    def create(self, vals):
        key = ''.join(random.choices(string.ascii_lowercase + string.digits, k = 48))
        user_id = super(res_users_ex, self).create(vals)
        if key:
            user_id.access_token = key

        return user_id

Here is the xml view file:

<?xml version="1.0" encoding="UTF-8"?>
    <record model="ir.ui.view" id="view_res_users_access_token">
        <field name="name">res.users.add.access.token</field>
        <field name="model">res.users</field>
        <field name="inherit_id" ref="base.view_users_form"/>
        <field name="type">form</field>
        <field name="arch" type="xml">
        <xpath expr="//notebook" position="inside">
            <page string="API Details">
               <group col="4">
                  <field name="access_token"/>

Now, after you have added this to a module, you can not simply upgrade this from App >> Module >> Upgrade. You need to upgrade this module via command line like the following:

First switch to your odoo user, in my case, it is ‘odoo’

su - odoo

Now, first stop your current odoo with the following:

service odoo14 stop

Once done, now you can upgrade the module with the following:

/usr/bin/scl enable rh-python36 -- /opt/odoo/odoo14-venv/bin/python3 /opt/odoo/odoo14/odoo-bin -d my_database-u res_users_access_token

The command above is explained like the following:

python3 odoo-bin -d your_databasename -u module_name

In my case, I use virtual environment and scl for python, hence the python3 source is like the following:

/usr/bin/scl enable rh-python36 -- /opt/odoo/odoo14-venv/bin/python3

The next one is the binary of odoo with it’s location, which should be odoo-bin. With the parameter -d, you give your database name, and with the parameter -u, you need to give your module name. After you run the command, you should see no ‘Error’ or Red marked line in your console. If not, it shall be upgraded. Now do control + c, and start your odoo again to see the new fields being visible in your Users tab.

Odoo Error – virtual real time limit (151/120s) reached.

There are times, when you might suddenly see your Odoo is shutdown automatically, without warning. Once you enable to logging, you could see an error like the following:

virtual real time limit (151/120s) reached.

or in full details like the following

2021-04-22 06:46:44,054 32685 WARNING ? odoo.service.server: Thread <Thread(odoo.service.http.request.140015617943296, started 140015617943296)> virtual real time limit (151/120s) reached.
2021-04-22 06:46:44,054 32685 INFO ? odoo.service.server: Dumping stacktrace of limit exceeding threads before reloading
2021-04-22 06:46:44,060 32685 INFO ?
# Thread: <Thread(odoo.service.http.request.140015617943296, started 140015617943296)> (db:n/a) (uid:n/a) (url:n/a)
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 884, in _bootstrap
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 916, in _bootstrap_inner
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 864, in run
  self._target(*self._args, **self._kwargs)
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 654, in process_request_thread
  self.finish_request(request, client_address)
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 364, in finish_request
  self.RequestHandlerClass(request, client_address, self)
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 724, in __init__
File: "/opt/odoo/odoo14-venv/lib64/python3.6/site-packages/werkzeug/", line 329, in handle
  rv = BaseHTTPRequestHandler.handle(self)
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/http/", line 418, in handle
File: "/opt/odoo/odoo14-venv/lib64/python3.6/site-packages/werkzeug/", line 360, in handle_one_request
  self.raw_requestline = self.rfile.readline()
File: "/opt/rh/rh-python36/root/usr/lib64/python3.6/", line 586, in readinto
  return self._sock.recv_into(b)
2021-04-22 06:46:44,060 32685 INFO ? odoo.service.server: Initiating server reload

This is because Odoo is killing zombie processes and probably mistakenly crashing your Odoo completely while doing so. The parameter that is used for this purpose, can be found in Odoo documentation:

--limit-time-real <limit>
Prevents the worker from taking longer than <limit> seconds to process a request. If the limit is exceeded, the worker is killed.

Differs from --limit-time-cpu in that this is a “wall time” limit including e.g. SQL queries.

Defaults to 120.

You may start your service command with something like –limit-time-real 100000 to avoid Odoo from auto killing processes. A command could look like the following if you edit your service file located at:


The exec would be like the following:

ExecStart=/usr/bin/scl enable rh-python36 -- /opt/odoo/odoo14-venv/bin/python3 /opt/odoo/odoo14/odoo-bin -c /etc/odoo.conf --limit-time-real=100000

Once the change is done, save the file, and reload the system daemon and restart your Odoo

systemctl daemon-reload
service odoo14 restart

How to Enable Logging in Odoo

There are two ways to see the Odoo Logs. One is rough and can be used to see the latest Odoo logs, it’s the Journal tools. You may do this using the following if your Odoo service is installed as odoo13 for example

journalctl -u odoo13

Note: If you are having trouble primarily in installing Odoo properly, you may check the following:

The other way, is the enable logging to a file. This has to be enabled from the odoo.conf file which is located under /etc/ folder. First we open the /etc/odoo.conf file:

nano /etc/odoo.conf

Now, search to see if you have a directive called ‘logfile’. If you don’t, you may add the following to /etc/odoo.conf:

logfile = /var/log/odoo13/odoo.log

If you already have the directive, but commented out, like this:

; logfile = /var/log/odoo13/odoo.log

You may remove the ‘;’ in front of the logfile directive and save the file. Now you may restart your Odoo instance to allow odoo log the information to the file /var/log/odoo13/odoo.log

systemctl restart odoo13

If the restart showing some errors, probably because it is failing to put permission to odoo13 folder. You may try the following:

mkdir /var/log/odoo13
chown -Rf odoo:odoo /var/log/odoo13
systemctl restart odoo13

Odoo Controller JSON Route Returns 404 – werkzeug.exceptions.NotFound

Even though, if you have defined your routes properly, you are seeing an error of the following:

    "id": null,
    "jsonrpc": "2.0",
    "error": {
        "http_status": 404,
        "code": 404,
        "data": {
            "name": "werkzeug.exceptions.NotFound",
            "debug": "Traceback (most recent call last):\n  File \"/opt/odoo/odoo12/odoo/\", line 656, in _handle_exception\n    return super(JsonRequest, self)._handle_exception(exception)\n  File \"/opt/odoo/odoo12/odoo/\", line 314, in _handle_exception\n    raise pycompat.reraise(type(exception), exception, sys.exc_info()[2])\n  File \"/opt/odoo/odoo12/odoo/tools/\", line 87, in reraise\n    raise value\n  File \"/opt/odoo/odoo12/odoo/\", line 1460, in _dispatch_nodb\n    func, arguments = self.nodb_routing_map.bind_to_environ(request.httprequest.environ).match()\n  File \"/opt/odoo/odoo12-venv/lib64/python3.5/site-packages/werkzeug/\", line 1563, in match\n    raise NotFound()\nwerkzeug.exceptions.NotFound: 404: Not Found\n",
            "message": "404: Not Found",
            "exception_type": "internal_error",
            "arguments": []
        "message": "404: Not Found"

This error doesn’t return when you use the http.route as type ‘http’ or default, which is still http, but returns when you use the type ‘json’. One of the cause why the error return is that, you have multiple Odoo databases and Odoo is failing to detect the usable database for the type json. For the type, http, Odoo usually can predict what to use, while for the type json, it can not. For such cases, you would need to use the ‘db-filter’ to add the default database to load for Odoo on the odoo-bin command. If you are using the systemd service file, append the line with the following:


where ‘my_prod’ is your database name.

So the service ExecStart would look like the following:

ExecStart=/usr/bin/scl enable rh-python35 -- /opt/odoo/odoo12-venv/bin/python3 /opt/odoo/odoo12/odoo-bin -c /etc/odoo.conf --limit-time-real 1009999999 --limit-time-cpu 1009999999 --limit-memory-hard 89179869184000000 --limit-memory-soft 57179869184000000 --db-filter=^my_prod$

After making the change, reload your systemctl and restart your odoo-bin:

systemctl daemon-reload
service odoo12 restart

This should do the job.