Relax Stickiness Rules for Strains with Conditions

[trieloff]

Previously, we assumed a strain with a url was not sticky, but a strain with a condition was. Now, that URLs have moved below conditions, every strain with a condition is sticky, even if it wasn't before.

I suggest we relax the stickiness rules so that the condition will actually be evaluated for stickiness.

Based on the list of conditions here, I'd suggest:

sticky

• referer
• url_param

** conditionally sticky** (sticky when at least one component condition is sticky)

• and
• or
• not

not sticky

• everything else

[dominique-pfister]

Looking at the existing tests in helix-shared a string condition is considered rendering the strain sticky as well, e.g. this strain:

  - <<: *basestrain
    name: pipeline
    condition: req.http.host == "pipeline.project-helix.io"
    params:
      - search
      - lang
    content:
      repo: hypermedia-pipeline
      ref: master
      owner: adobe
    static:
      <<: *myrepo
      path: /www
    redirects:
      - from: (.*)\.php
        to: $1.html
      - from: /content/dam/(.*)$
        to: /htdocs/$1

is expected to have canonical form:

  - code:
      protocol: https
      host: github.com
      port: ""
      hostname: github.com
      owner: adobe
      repo: project-helix.io
      ref: master
      path: ""
    content:
      protocol: https
      host: github.com
      port: ""
      hostname: github.com
      owner: adobe
      repo: hypermedia-pipeline
      ref: master
      path: ""
    static:
      magic: false
      allow: []
      deny: []
      protocol: https
      host: github.com
      port: ""
      hostname: github.com
      owner: adobe
      repo: project-helix.io
      ref: master
      path: /www
    directoryIndex: index.html
    package: ""
    name: pipeline
    sticky: true
    condition: req.http.host == "pipeline.project-helix.io"
    perf:
      device: ""
      location: ""
      connection: ""
    urls: []
    params:
      - search
      - lang
    redirects:
      - from: (.*)\.php
        to: $1.html
      - from: \/content\/dam\/(.*)$
        to: /htdocs/$1

What do you think, @trieloff : should I rework the stickyness in the expected output(s) or assume string-based conditions are always sticky, which as mentioned would make all tests pass?

[trieloff]

I'd phrase the old policy as: "when in doubt, treat it as sticky". Because we couldn't understand string based conditions, they were always sticky.

With the new condition expressions, we can be more precise, and treat a condition like req.http.host == "pipeline.project-helix.io" as non-sticky, as it does not rely on either referrer or cookies or URL parameters.

[dominique-pfister]

So, I remove the sticky: true in the expected output?

[trieloff]

Yes.