--- /dev/null
+Syncing Upstream Updates
+========================
+
+Updating the facade and definitions code generated from the schema
+to reflect changes in upstream Juju consists of two steps:
+
+* Creating a new `schemas-juju-<version>.json` file from the Juju code-base
+* Generating the libjuju Python code from that schema
+
+Rarely, you may also have to add or update an override.
+
+
+Creating a Schema File
+----------------------
+
+First, you will need to fetch SchemaGen_ and a copy of the Juju source.
+Once your copy of the Juju source is at the version you want to update to
+(probably the `develop` branch, or a release tag) and you have updated
+and reinstalled SchemaGen to reflect those changes, you just need to send
+the output into a file in the libjuju repository:
+
+.. code:: bash
+
+ schemagen > juju/client/schemas-juju-2.2-rc1.json
+
+The version number you use in the filename should match the upstream
+version of Juju. You should then also move the `latest` pointer to
+the new file:
+
+.. code:: bash
+
+ rm juju/client/schemas-juju-latest.json
+ ln -s schemas-juju-2.2-rc1.json juju/client/schemas-juju-latest.json
+
+
+Generating the Python Code
+--------------------------
+
+Once you have a new schema file, you can update the Python code
+using the `client` make target:
+
+.. code:: bash
+
+ make client
+
+You should expect to see updates to the `juju/client/_definitions.py` file,
+as well as one or more of the `juju/client/_clientX.py` files, depending on
+which facades were touched.
+
+
+Integrating into the Object Layer
+---------------------------------
+
+Once the raw client APIs are synced, you may need to integrate any new or
+changed API calls into the object layer, to provide a clean, Pythonic way
+to interact with the model. This may be as simple as adding an optional
+parameter to an existing model method, tweaking what manipulations, if any
+the model method does to the data before it is sent to the API, or it may
+require adding an entirely new model method to capture the new functionality.
+
+In general, the approach should be to make the interactions with the model
+layer use the same patterns as when you use the CLI, just with Python idioms
+and OO approaches.
+
+When trying to determine what client calls need to be made and what data to
+be sent for a given Juju CLI action, it is very useful to add
+`--debug --logging-config TRACE` to any Juju CLI command to view the full
+conversation between the CLI client and the API server. For example:
+
+```
+[johnsca@murdoch:~] $ juju deploy --debug --logging-config TRACE ./builds/test
+11:51:20 INFO juju.cmd supercommand.go:56 running juju [2.3.5 gc go1.10]
+11:51:20 DEBUG juju.cmd supercommand.go:57 args: []string{"/snap/juju/3884/bin/juju", "deploy", "--debug", "--logging-config", "TRACE", "./builds/test"}
+11:51:20 INFO juju.juju api.go:67 connecting to API addresses: [35.172.119.191:17070 172.31.94.16:17070 252.94.16.1:17070]
+11:51:20 TRACE juju.api certpool.go:49 cert dir "/etc/juju/certs.d" does not exist
+11:51:20 DEBUG juju.api apiclient.go:843 successfully dialed "wss://35.172.119.191:17070/model/a7317969-6dab-4ba4-844b-af3d661c228d/api"
+11:51:20 INFO juju.api apiclient.go:597 connection established to "wss://35.172.119.191:17070/model/a7317969-6dab-4ba4-844b-af3d661c228d/api"
+...
+11:51:20 INFO juju.cmd.juju.application series_selector.go:71 with the configured model default series "xenial"
+11:51:20 DEBUG httpbakery client.go:244 client do POST https://35.172.119.191:17070/model/a7317969-6dab-4ba4-844b-af3d661c228d/charms?revision=0&schema=local&series=xenial {
+11:51:21 DEBUG httpbakery client.go:246 } -> error <nil>
+11:51:21 INFO cmd deploy.go:1096 Deploying charm "local:xenial/test-0".
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:225 -> {"request-id":3,"type":"Charms","version":2,"request":"CharmInfo","params":{"url":"local:xenial/test-0"}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:120 <- {"request-id":3,"response":{"revision":0,"url":"local:xenial/test-0","config":{"test":{"type":"string","default":""}},"meta":{"name":"test","summary":"test","description":"test","subordinate":false,"series":["xenial"],"resources":{"dummy":{"name":"dummy","type":"file","path":"dummy.snap","description":"dummy snap"}},"min-juju-version":"0.0.0"},"actions":{}}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:225 -> {"request-id":4,"type":"Charms","version":2,"request":"IsMetered","params":{"url":"local:xenial/test-0"}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:120 <- {"request-id":4,"response":{"metered":false}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:225 -> {"request-id":5,"type":"Resources","version":1,"request":"AddPendingResources","params":{"tag":"application-test","url":"local:xenial/test-0","channel":"","macaroon":null,"resources":[{"name":"dummy","type":"file","path":"dummy.snap","description":"dummy snap","origin":"store","revision":-1,"fingerprint":"","size":0}]}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:120 <- {"request-id":5,"response":{"pending-ids":["c0ffdd92-da23-4fb2-8d41-d82d58423447"]}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:225 -> {"request-id":6,"type":"Application","version":5,"request":"Deploy","params":{"applications":[{"application":"test","series":"xenial","charm-url":"local:xenial/test-0","channel":"","num-units":1,"config-yaml":"","constraints":{},"resources":{"dummy":"c0ffdd92-da23-4fb2-8d41-d82d58423447"}}]}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:120 <- {"request-id":6,"response":{"results":[{}]}}
+11:51:21 TRACE juju.rpc.jsoncodec codec.go:123 <- error: read tcp 192.168.1.102:52168->35.172.119.191:17070: use of closed network connection (closing true)
+11:51:21 DEBUG juju.api monitor.go:35 RPC connection died
+11:51:21 INFO cmd supercommand.go:465 command finished
+```
+
+Note that this will contain login information (which has been removed from the above).
+
+
+Overrides
+---------
+
+It should be quite rare, but occasionally the generated Python code does
+not capture all of the logic needed to properly parse the output from the API
+or may otherwise need some small amount of tweaking. This is what the
+`juju/client/overrides.py` file is for. An example of this is the `Number`
+type, which isn't standard JSON and must be parsed slightly differently.
+
+At the top of that file are two lists, `__all__` and `__patches__`. The
+former replaces entire class implementations, while the latter patches
+the attributes of the override classes into the matching generated class,
+leaving the rest of the generated class untouched.
+
+
+.. _SchemaGen: https://github.com/juju/schemagen
projects / osm / N2VC.git / blobdiff