add capability to set an instance identifier which labels all metrics

[gvelez17]

set instance identifier - #WS2-3187

Description

The current CAS metrics are being sent from the 6 different api nodes with the same name and labels, resulting in inaccurate metrics, stepping on totals, odd reset patterns. Each instance should have a distinct label. This PR uses the task id as the label and uses the new observability functionality of Instance Identifier to automatically label all metrics (see ceramicnetwork/observability#29)

How Has This Been Tested?

Describe the tests that you ran to verify your changes. Provide instructions for reproduction.

• [ x] observability package new unit tests
• unit tests in this pr

Definition of Done

Before submitting this PR, please make sure:

• [x ] The work addresses the description and outcomes in the issue
• [ x] I have added relevant tests for new or updated functionality
• My code follows conventions, is well commented, and easy to understand
• My code builds and tests pass without any errors or warnings
• I have tagged the relevant reviewers
• I have updated the READMEs of affected packages
• I have made corresponding changes to the documentation
• The changes have been communicated to interested parties

References:

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 81.48%. Comparing base (dc77998) to head (6cafafe).

Files	Patch %	Lines
src/app.ts	50.00%	1 Missing ⚠️

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Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1198      +/-   ##
===========================================
- Coverage    81.51%   81.48%   -0.04%     
===========================================
  Files           46       46              
  Lines         1829     1831       +2     
  Branches       289      290       +1     
===========================================
+ Hits          1491     1492       +1     
- Misses         338      339       +1     

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[3benbox]

Just a question about how the value gets set.

[3benbox]

lgtm

[smrz2001]

It would be nice to inject this through the Dockerfile via an ENTRYPOINT script and call it INSTANCE_ID or something like that.

We do have AWS specific stuff in the env vars and code but parsing a very specific ECS env var directly in the code seems undesirable.

entrypoint.sh:

#!/bin/bash

uri=$ECS_CONTAINER_METADATA_URI

# Parse the last portion of the URI
value=${uri##*/}

# Remove everything after the hyphen to get the task ID
value=${value%%-*}

export INSTANCE_ID=$value

exec "$@"

Dockerfile:

.
.
.
WORKDIR /

COPY entrypoint.sh .
RUN chmod +x ./entrypoint.sh

COPY runner.sh .

ENTRYPOINT ["./entrypoint.sh"]
CMD [ "./runner.sh" ]

[3benbox]

We do have AWS specific stuff in the env vars and code but parsing a very specific ECS env var directly in the code seems undesirable.

Oh yeah, good call!

[smrz2001]

If done using the entrypoint.sh script above, we won't need to parse this in the code here.

[gvelez17]

right! the logic isn't quite the same - not sure if it matters, i was defaulting to the full uri if there wasn't a task id at the end - but i agree yours is better, since it moves it to the deployment and therefore we can make it very specific to what we expect!