Adding trigger docs

docs/book/how-to/trigger-pipelines/trigger-a-pipeline-from-rest-api.md

@@ -24,12 +24,17 @@ The above set of REST calls means that you can only trigger a pipeline that has
 
 ## A worked example
 
+{% hint style="info" %}
+Learn how to get a bearer token for the curl commands [here](../../reference/api-reference.md#using-a-bearer-token-to-access-the-api-programatically).
+{% endhint %}
+
 Here is an example. Let's say would we like to re-run a pipeline called `training`. We first query the `/pipelines` endpoint:
 
 ```shell
 curl -X 'GET' \
   '<YOUR_ZENML_SERVER_URL>/api/v1/pipelines?hydrate=false&name=training&version=45' \
-  -H 'accept: application/json'
+  -H 'accept: application/json' \
+  -H 'Authorization: Bearer <YOUR_TOKEN>'
 ```
 
 <figure><img src="../../.gitbook/assets/rest_api_step_1.png" alt=""><figcaption><p>Identifying the pipeline ID</p></figcaption></figure>
@@ -41,7 +46,8 @@ After this, we take the pipeline ID and call the `/pipeline_builds?pipeline_id=<
 ```shell
 curl -X 'GET' \
   '<YOUR_ZENML_SERVER_URL>/api/v1/pipeline_builds?hydrate=false&logical_operator=and&page=1&size=20&pipeline_id=b826b714-a9b3-461c-9a6e-1bde3df3241d' \
-  -H 'accept: application/json'
+  -H 'accept: application/json' \
+  -H 'Authorization: Bearer <YOUR_TOKEN>'
 ```
 
 We can now take the <BUILD_ID> from this response. Here it is `b826b714-a9b3-461c-9a6e-1bde3df3241d`.
@@ -55,6 +61,7 @@ curl -X 'POST' \
   '<YOUR_ZENML_SERVER_URL>/api/v1/pipeline_builds/b826b714-a9b3-461c-9a6e-1bde3df3241d/runs' \
   -H 'accept: application/json' \
   -H 'Content-Type: application/json' \
+  -H 'Authorization: Bearer <YOUR_TOKEN>' \
   -d '{
   "steps": {"model_trainer": {"parameters": {"model_type": "rf"}}}
 }'

docs/book/reference/api-reference.md

@@ -15,4 +15,50 @@ In the local case (i.e. using `zenml up`, the docs are available on `http://127.
 
 ![ZenML API Redoc](../.gitbook/assets/zenml_api_redoc.png)
 
+## Using a bearer token to access the API programatically
+
+If you are using the ZenML server API using the above pages, it is enough to be logged in to your ZenML
+account in the same browser session. However, in order to do this programatically, the following steps
+need to be followed:
+
+1. Create a [service account](../how-to/connecting-to-zenml/connect-with-a-service-account.md):
+
+```shell
+zenml service-account create myserviceaccount
+```
+
+This will print out the `<ZENML_API_KEY>`, you can use in the next command.
+
+2. Get an access token by using the `/api/v1/login` endpoint:
+
+```shell
+
+curl -X 'POST' \
+  '<YOUR_ZENML_SERVER_URL>/api/v1/login' \
+  -H 'accept: application/json' \
+  -H 'Content-Type: application/x-www-form-urlencoded' \
+  -d 'grant_type=zenml-api-key&username=&password=<ZENML_API_KEY>'\''&client_id=&device_code='
+```
+
+This will return a response like this:
+
+```json
+{
+  "access_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiI3MGJjZTg5NC1hN2VjLTRkOTYtYjE1Ny1kOTZkYWY5ZWM2M2IiLCJpc3MiOiJmMGQ5NjI1Ni04YmQyLTQxZDctOWVjZi0xMmYwM2JmYTVlMTYiLCJhdWQiOiJmMGQ5NjI1Ni04YmQyLTQxZDctOWVjZi0xMmYwM2JmYTVlMTYiLCJleHAiOjE3MTk0MDk0NjAsImFwaV9rZXlfaWQiOiIzNDkyM2U0NS0zMGFlLTRkMjctODZiZS0wZGRhNTdkMjA5MDcifQ.ByB1ngCPtBenGE6UugsWC6Blga3qPqkAiPJUSFDR-u4",
+  "token_type": "bearer",
+  "expires_in": 3600,
+  "refresh_token": null,
+  "scope": null
+}
+```
+
+3. Use the access token to make subsequent curl commands:
+
+```shell
+curl -X 'GET' \
+  '<YOUR_ZENML_SERVER_URL>/api/v1/pipelines?hydrate=false&name=training&version=45' \
+  -H 'accept: application/json' \
+  -H 'Authorization: Bearer <ACCESS_TOKEN>'
+```
+
 <figure><img src="https://static.scarf.sh/a.png?x-pxid=f0b4f458-0a54-4fcd-aa95-d5ee424815bc" alt="ZenML Scarf"><figcaption></figcaption></figure>