Using the APIs

The Mender Server microservices are all accessible using an HTTPS API. These APIs can be used to configure the server (for example, preauthorizing devices) or implementing custom workflows (for example, integrating the Mender Server into an existing device management system.) The APIs are documented in API chatper.

There are many ways to interact with Mender's REST APIs and the most common ones are shown below.

Install cURL and jq and set up the shell variables

There are many ways to call HTTP-based REST APIs, but the command line utility curl is the most generally available method.

The jq utility is commonly used to decode JSON messages and display them in a human-readable format. REST API responses contain raw JSON data and must run through a JSON parser (jq).

On a Debian-derived system, you can easily install both running:

sudo apt-get install curl jq

Open a terminal, which we will use in the following to call the Mender Server's REST APIs. First set a shell variable with the URI of your server:

MENDER_SERVER_URI='https://hosted.mender.io'

Next, set a variable with your user email on the Mender Server (replace its content with your user email):

MENDER_SERVER_USER='myusername@example.com'

Now obtain a management API JSON Web Token by using the login API:

JWT=$(curl -X POST -u $MENDER_SERVER_USER $MENDER_SERVER_URI/api/management/v1/useradm/auth/login)

You should now have an API token you can use to call any of the Mender Server management APIs in the JWT shell variable.

Verify you can call the APIs

To verify you can call the server APIs, you can get your user's details:

curl -H "Authorization: Bearer $JWT" $MENDER_SERVER_URI/api/management/v1/useradm/users/me | jq '.'

If it succeeds, it will return:

{
  "id": "0a6c526c-4637-4a62-bf38-81aa70c4aa59",
  "email": "mender-demo@example.com",
  "created_ts": "2022-06-08T03:58:28.582Z",
  "updated_ts": "2022-06-08T03:58:28.582Z",
  "login_ts": "2022-06-08T04:02:06.855Z"
}

If this fails, e.g. returns 401 Authorization Required, make sure that the contents of your JWT and MENDER_SERVER_URI shell variables are correct and re-run the steps above if necessary.

Personal Access Tokens

Personal Access Tokens are long-lived JWT tokens that you can use to programmatically access the Mender management APIs without logging in each time you need to perform API calls nor handle the JWT token expiration every week. Personal Access Tokens act as API keys you can use from your CI/CD pipelines or scheduled jobs to access the Mender management APIs.

You can generate a Personal Access Token using the web-based UI from the "My profile" page or the following API call:

PERSONAL_ACCESS_TOKEN=$(curl -H "Authorization: Bearer $JWT" -H "Content-Type: application/json" -X POST $MENDER_SERVER_URI/api/management/v1/useradm/settings/tokens -d '{"name": "my_token", "expires_in": 31536000}')

Personal Access Tokens have a unique name and an expiration time in seconds, up to one year (31536000 seconds). Once generated, the server won't return the content of the access token anymore. Therefore, it is your responsibility to store its value securely.

You can list your Personal Access Tokens as follows:

curl -H "Authorization: Bearer $JWT" -k $MENDER_SERVER_URI/api/management/v1/useradm/settings/tokens | jq '.'

[
  {
    "id": "767c2a29-a983-45ce-b58f-c4379d1b8ee8",
    "name": "my_token",
    "expiration_date": "2023-06-08T04:02:36.298Z",
    "created_ts": "2022-06-08T04:02:36.298Z"
  }
]

You can now use your Personal Access Token to perform API calls:

curl -H "Authorization: Bearer $PERSONAL_ACCESS_TOKEN" $MENDER_SERVER_URI/api/management/v1/useradm/users/me | jq '.'

If it succeeds, it will return:

{
  "id": "0a6c526c-4637-4a62-bf38-81aa70c4aa59",
  "email": "mender-demo@example.com",
  "created_ts": "2022-06-08T03:58:28.582Z",
  "updated_ts": "2022-06-08T03:58:28.582Z",
  "login_ts": "2022-06-08T04:02:06.855Z"
}

You can revoke a Personal Access Token by calling the following API end-point using the token ID:

curl -H "Authorization: Bearer $JWT" -X DELETE -k $MENDER_SERVER_URI/api/management/v1/useradm/settings/tokens/0a6c526c-4637-4a62-bf38-81aa70c4aa59

Set up mender-cli

mender-cli is a standalone CLI tool that works as a client against the Mender Server management APIs in order to make it much easier to interact with the APIs.

It supports use cases for cloud systems, like uploading an Artifact to the Mender Server, as well as end user workstation use cases like Remote terminal and Port forward (Troubleshoot add-on required).

Over time the functionality of mender-cli will be extended to simplify the most common use cases for integrating the Mender Server into other backend and cloud systems. If you need to cover other use cases today, follow the tutorial for cURL instead.

First download the prebuilt mender-cli Linux binary here.

Then open a terminal in the directory you downloaded mender-cli and run the following commands to log in to your Mender Server.

chmod +x mender-cli
./mender-cli login --server https://hosted.mender.io --username myusername@example.com

If the log in succeeds, you should see a message similar to the following:

login successful

You can now use the other options of mender-cli to interact with the APIs. For example, to upload an Artifact you can run the following command:

./mender-cli artifacts --server https://hosted.mender.io upload release_1.mender

Instead of logging in using your credentials, you can specify a Personal Access Token:

./mender-cli artifacts --server https://hosted.mender.io --token-value $PERSONAL_ACCESS_TOKEN upload release_1.mender